1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "interpreter/linkResolver.hpp"
28 #include "oops/method.hpp"
29 #include "opto/addnode.hpp"
30 #include "opto/castnode.hpp"
31 #include "opto/idealGraphPrinter.hpp"
32 #include "opto/locknode.hpp"
33 #include "opto/memnode.hpp"
34 #include "opto/opaquenode.hpp"
35 #include "opto/parse.hpp"
36 #include "opto/rootnode.hpp"
37 #include "opto/runtime.hpp"
38 #include "runtime/arguments.hpp"
39 #include "runtime/handles.inline.hpp"
40 #include "runtime/sharedRuntime.hpp"
41 #include "utilities/copy.hpp"
42
43 // Static array so we can figure out which bytecodes stop us from compiling
44 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
45 // and eventually should be encapsulated in a proper class (gri 8/18/98).
46
47 int nodes_created = 0;
48 int methods_parsed = 0;
49 int methods_seen = 0;
50 int blocks_parsed = 0;
51 int blocks_seen = 0;
52
53 int explicit_null_checks_inserted = 0;
54 int explicit_null_checks_elided = 0;
55 int all_null_checks_found = 0, implicit_null_checks = 0;
56 int implicit_null_throws = 0;
57
58 int reclaim_idx = 0;
59 int reclaim_in = 0;
60 int reclaim_node = 0;
61
62 #ifndef PRODUCT
63 bool Parse::BytecodeParseHistogram::_initialized = false;
64 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
65 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
66 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
67 uint Parse::BytecodeParseHistogram::_new_values [Bytecodes::number_of_codes];
68 #endif
69
70 //------------------------------print_statistics-------------------------------
71 #ifndef PRODUCT
72 void Parse::print_statistics() {
73 tty->print_cr("--- Compiler Statistics ---");
74 tty->print("Methods seen: %d Methods parsed: %d", methods_seen, methods_parsed);
75 tty->print(" Nodes created: %d", nodes_created);
76 tty->cr();
77 if (methods_seen != methods_parsed)
78 tty->print_cr("Reasons for parse failures (NOT cumulative):");
79 tty->print_cr("Blocks parsed: %d Blocks seen: %d", blocks_parsed, blocks_seen);
80
81 if( explicit_null_checks_inserted )
82 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);
83 if( all_null_checks_found )
84 tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
85 (100*implicit_null_checks)/all_null_checks_found);
86 if( implicit_null_throws )
87 tty->print_cr("%d implicit null exceptions at runtime",
88 implicit_null_throws);
89
90 if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
91 BytecodeParseHistogram::print();
92 }
93 }
94 #endif
95
96 //------------------------------ON STACK REPLACEMENT---------------------------
97
98 // Construct a node which can be used to get incoming state for
99 // on stack replacement.
100 Node *Parse::fetch_interpreter_state(int index,
101 BasicType bt,
102 Node *local_addrs,
103 Node *local_addrs_base) {
104 Node *mem = memory(Compile::AliasIdxRaw);
105 Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
106 Node *ctl = control();
107
108 // Very similar to LoadNode::make, except we handle un-aligned longs and
109 // doubles on Sparc. Intel can handle them just fine directly.
110 Node *l;
111 switch (bt) { // Signature is flattened
112 case T_INT: l = new (C) LoadINode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInt::INT, MemNode::unordered); break;
113 case T_FLOAT: l = new (C) LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT, MemNode::unordered); break;
114 case T_ADDRESS: l = new (C) LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, MemNode::unordered); break;
115 case T_OBJECT: l = new (C) LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); break;
116 case T_LONG:
117 case T_DOUBLE: {
118 // Since arguments are in reverse order, the argument address 'adr'
119 // refers to the back half of the long/double. Recompute adr.
120 adr = basic_plus_adr(local_addrs_base, local_addrs, -(index+1)*wordSize);
121 if (Matcher::misaligned_doubles_ok) {
122 l = (bt == T_DOUBLE)
123 ? (Node*)new (C) LoadDNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::DOUBLE, MemNode::unordered)
124 : (Node*)new (C) LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
125 } else {
126 l = (bt == T_DOUBLE)
127 ? (Node*)new (C) LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
128 : (Node*)new (C) LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
129 }
130 break;
131 }
132 default: ShouldNotReachHere();
133 }
134 return _gvn.transform(l);
135 }
136
137 // Helper routine to prevent the interpreter from handing
138 // unexpected typestate to an OSR method.
139 // The Node l is a value newly dug out of the interpreter frame.
140 // The type is the type predicted by ciTypeFlow. Note that it is
141 // not a general type, but can only come from Type::get_typeflow_type.
142 // The safepoint is a map which will feed an uncommon trap.
143 Node* Parse::check_interpreter_type(Node* l, const Type* type,
144 SafePointNode* &bad_type_exit) {
145
146 const TypeOopPtr* tp = type->isa_oopptr();
147
148 // TypeFlow may assert null-ness if a type appears unloaded.
149 if (type == TypePtr::NULL_PTR ||
150 (tp != NULL && !tp->klass()->is_loaded())) {
151 // Value must be null, not a real oop.
152 Node* chk = _gvn.transform( new (C) CmpPNode(l, null()) );
153 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
154 IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
155 set_control(_gvn.transform( new (C) IfTrueNode(iff) ));
156 Node* bad_type = _gvn.transform( new (C) IfFalseNode(iff) );
157 bad_type_exit->control()->add_req(bad_type);
158 l = null();
159 }
160
161 // Typeflow can also cut off paths from the CFG, based on
162 // types which appear unloaded, or call sites which appear unlinked.
163 // When paths are cut off, values at later merge points can rise
164 // toward more specific classes. Make sure these specific classes
165 // are still in effect.
166 if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
167 // TypeFlow asserted a specific object type. Value must have that type.
168 Node* bad_type_ctrl = NULL;
169 l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
170 bad_type_exit->control()->add_req(bad_type_ctrl);
171 }
172
173 BasicType bt_l = _gvn.type(l)->basic_type();
174 BasicType bt_t = type->basic_type();
175 assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
176 return l;
177 }
178
179 // Helper routine which sets up elements of the initial parser map when
180 // performing a parse for on stack replacement. Add values into map.
181 // The only parameter contains the address of a interpreter arguments.
182 void Parse::load_interpreter_state(Node* osr_buf) {
183 int index;
184 int max_locals = jvms()->loc_size();
185 int max_stack = jvms()->stk_size();
186
187
188 // Mismatch between method and jvms can occur since map briefly held
189 // an OSR entry state (which takes up one RawPtr word).
190 assert(max_locals == method()->max_locals(), "sanity");
191 assert(max_stack >= method()->max_stack(), "sanity");
192 assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
193 assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
194
195 // Find the start block.
196 Block* osr_block = start_block();
197 assert(osr_block->start() == osr_bci(), "sanity");
198
199 // Set initial BCI.
200 set_parse_bci(osr_block->start());
201
202 // Set initial stack depth.
203 set_sp(osr_block->start_sp());
204
205 // Check bailouts. We currently do not perform on stack replacement
206 // of loops in catch blocks or loops which branch with a non-empty stack.
207 if (sp() != 0) {
208 C->record_method_not_compilable("OSR starts with non-empty stack");
209 return;
210 }
211 // Do not OSR inside finally clauses:
212 if (osr_block->has_trap_at(osr_block->start())) {
213 C->record_method_not_compilable("OSR starts with an immediate trap");
214 return;
215 }
216
217 // Commute monitors from interpreter frame to compiler frame.
218 assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
219 int mcnt = osr_block->flow()->monitor_count();
220 Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
221 for (index = 0; index < mcnt; index++) {
222 // Make a BoxLockNode for the monitor.
223 Node *box = _gvn.transform(new (C) BoxLockNode(next_monitor()));
224
225
226 // Displaced headers and locked objects are interleaved in the
227 // temp OSR buffer. We only copy the locked objects out here.
228 // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
229 Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
230 // Try and copy the displaced header to the BoxNode
231 Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
232
233
234 store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
235
236 // Build a bogus FastLockNode (no code will be generated) and push the
237 // monitor into our debug info.
238 const FastLockNode *flock = _gvn.transform(new (C) FastLockNode( 0, lock_object, box ))->as_FastLock();
239 map()->push_monitor(flock);
240
241 // If the lock is our method synchronization lock, tuck it away in
242 // _sync_lock for return and rethrow exit paths.
243 if (index == 0 && method()->is_synchronized()) {
244 _synch_lock = flock;
245 }
246 }
247
248 // Use the raw liveness computation to make sure that unexpected
249 // values don't propagate into the OSR frame.
250 MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
251 if (!live_locals.is_valid()) {
252 // Degenerate or breakpointed method.
253 C->record_method_not_compilable("OSR in empty or breakpointed method");
254 return;
255 }
256
257 // Extract the needed locals from the interpreter frame.
258 Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
259
260 // find all the locals that the interpreter thinks contain live oops
261 const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
262 for (index = 0; index < max_locals; index++) {
263
264 if (!live_locals.at(index)) {
265 continue;
266 }
267
268 const Type *type = osr_block->local_type_at(index);
269
270 if (type->isa_oopptr() != NULL) {
271
272 // 6403625: Verify that the interpreter oopMap thinks that the oop is live
273 // else we might load a stale oop if the MethodLiveness disagrees with the
274 // result of the interpreter. If the interpreter says it is dead we agree
275 // by making the value go to top.
276 //
277
278 if (!live_oops.at(index)) {
279 if (C->log() != NULL) {
280 C->log()->elem("OSR_mismatch local_index='%d'",index);
281 }
282 set_local(index, null());
283 // and ignore it for the loads
284 continue;
285 }
286 }
287
288 // Filter out TOP, HALF, and BOTTOM. (Cf. ensure_phi.)
289 if (type == Type::TOP || type == Type::HALF) {
290 continue;
291 }
292 // If the type falls to bottom, then this must be a local that
293 // is mixing ints and oops or some such. Forcing it to top
294 // makes it go dead.
295 if (type == Type::BOTTOM) {
296 continue;
297 }
298 // Construct code to access the appropriate local.
299 BasicType bt = type->basic_type();
300 if (type == TypePtr::NULL_PTR) {
301 // Ptr types are mixed together with T_ADDRESS but NULL is
302 // really for T_OBJECT types so correct it.
303 bt = T_OBJECT;
304 }
305 Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
306 set_local(index, value);
307 }
308
309 // Extract the needed stack entries from the interpreter frame.
310 for (index = 0; index < sp(); index++) {
311 const Type *type = osr_block->stack_type_at(index);
312 if (type != Type::TOP) {
313 // Currently the compiler bails out when attempting to on stack replace
314 // at a bci with a non-empty stack. We should not reach here.
315 ShouldNotReachHere();
316 }
317 }
318
319 // End the OSR migration
320 make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
321 CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
322 "OSR_migration_end", TypeRawPtr::BOTTOM,
323 osr_buf);
324
325 // Now that the interpreter state is loaded, make sure it will match
326 // at execution time what the compiler is expecting now:
327 SafePointNode* bad_type_exit = clone_map();
328 bad_type_exit->set_control(new (C) RegionNode(1));
329
330 assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
331 for (index = 0; index < max_locals; index++) {
332 if (stopped()) break;
333 Node* l = local(index);
334 if (l->is_top()) continue; // nothing here
335 const Type *type = osr_block->local_type_at(index);
336 if (type->isa_oopptr() != NULL) {
337 if (!live_oops.at(index)) {
338 // skip type check for dead oops
339 continue;
340 }
341 }
342 if (osr_block->flow()->local_type_at(index)->is_return_address()) {
343 // In our current system it's illegal for jsr addresses to be
344 // live into an OSR entry point because the compiler performs
345 // inlining of jsrs. ciTypeFlow has a bailout that detect this
346 // case and aborts the compile if addresses are live into an OSR
347 // entry point. Because of that we can assume that any address
348 // locals at the OSR entry point are dead. Method liveness
349 // isn't precise enought to figure out that they are dead in all
350 // cases so simply skip checking address locals all
351 // together. Any type check is guaranteed to fail since the
352 // interpreter type is the result of a load which might have any
353 // value and the expected type is a constant.
354 continue;
355 }
356 set_local(index, check_interpreter_type(l, type, bad_type_exit));
357 }
358
359 for (index = 0; index < sp(); index++) {
360 if (stopped()) break;
361 Node* l = stack(index);
362 if (l->is_top()) continue; // nothing here
363 const Type *type = osr_block->stack_type_at(index);
364 set_stack(index, check_interpreter_type(l, type, bad_type_exit));
365 }
366
367 if (bad_type_exit->control()->req() > 1) {
368 // Build an uncommon trap here, if any inputs can be unexpected.
369 bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
370 record_for_igvn(bad_type_exit->control());
371 SafePointNode* types_are_good = map();
372 set_map(bad_type_exit);
373 // The unexpected type happens because a new edge is active
374 // in the CFG, which typeflow had previously ignored.
375 // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
376 // This x will be typed as Integer if notReached is not yet linked.
377 // It could also happen due to a problem in ciTypeFlow analysis.
378 uncommon_trap(Deoptimization::Reason_constraint,
379 Deoptimization::Action_reinterpret);
380 set_map(types_are_good);
381 }
382 }
383
384 //------------------------------Parse------------------------------------------
385 // Main parser constructor.
386 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses, Parse* parent)
387 : _exits(caller), _parent(parent)
388 {
389 // Init some variables
390 _caller = caller;
391 _method = parse_method;
392 _expected_uses = expected_uses;
393 _depth = 1 + (caller->has_method() ? caller->depth() : 0);
394 _wrote_final = false;
395 _wrote_volatile = false;
396 _wrote_stable = false;
397 _wrote_fields = false;
398 _alloc_with_final = NULL;
399 _entry_bci = InvocationEntryBci;
400 _tf = NULL;
401 _block = NULL;
402 debug_only(_block_count = -1);
403 debug_only(_blocks = (Block*)-1);
404 #ifndef PRODUCT
405 if (PrintCompilation || PrintOpto) {
406 // Make sure I have an inline tree, so I can print messages about it.
407 JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
408 InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
409 }
410 _max_switch_depth = 0;
411 _est_switch_depth = 0;
412 #endif
413
414 _tf = TypeFunc::make(method());
415 _iter.reset_to_method(method());
416 _flow = method()->get_flow_analysis();
417 if (_flow->failing()) {
418 C->record_method_not_compilable_all_tiers(_flow->failure_reason());
419 }
420
421 #ifndef PRODUCT
422 if (_flow->has_irreducible_entry()) {
423 C->set_parsed_irreducible_loop(true);
424 }
425 #endif
426
427 if (_expected_uses <= 0) {
428 _prof_factor = 1;
429 } else {
430 float prof_total = parse_method->interpreter_invocation_count();
431 if (prof_total <= _expected_uses) {
432 _prof_factor = 1;
433 } else {
434 _prof_factor = _expected_uses / prof_total;
435 }
436 }
437
438 CompileLog* log = C->log();
439 if (log != NULL) {
440 log->begin_head("parse method='%d' uses='%g'",
441 log->identify(parse_method), expected_uses);
442 if (depth() == 1 && C->is_osr_compilation()) {
443 log->print(" osr_bci='%d'", C->entry_bci());
444 }
445 log->stamp();
446 log->end_head();
447 }
448
449 // Accumulate deoptimization counts.
450 // (The range_check and store_check counts are checked elsewhere.)
451 ciMethodData* md = method()->method_data();
452 for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
453 uint md_count = md->trap_count(reason);
454 if (md_count != 0) {
455 if (md_count == md->trap_count_limit())
456 md_count += md->overflow_trap_count();
457 uint total_count = C->trap_count(reason);
458 uint old_count = total_count;
459 total_count += md_count;
460 // Saturate the add if it overflows.
461 if (total_count < old_count || total_count < md_count)
462 total_count = (uint)-1;
463 C->set_trap_count(reason, total_count);
464 if (log != NULL)
465 log->elem("observe trap='%s' count='%d' total='%d'",
466 Deoptimization::trap_reason_name(reason),
467 md_count, total_count);
468 }
469 }
470 // Accumulate total sum of decompilations, also.
471 C->set_decompile_count(C->decompile_count() + md->decompile_count());
472
473 _count_invocations = C->do_count_invocations();
474 _method_data_update = C->do_method_data_update();
475
476 if (log != NULL && method()->has_exception_handlers()) {
477 log->elem("observe that='has_exception_handlers'");
478 }
479
480 assert(method()->can_be_compiled(), "Can not parse this method, cutout earlier");
481 assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
482
483 // Always register dependence if JVMTI is enabled, because
484 // either breakpoint setting or hotswapping of methods may
485 // cause deoptimization.
486 if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
487 C->dependencies()->assert_evol_method(method());
488 }
489
490 methods_seen++;
491
492 // Do some special top-level things.
493 if (depth() == 1 && C->is_osr_compilation()) {
494 _entry_bci = C->entry_bci();
495 _flow = method()->get_osr_flow_analysis(osr_bci());
496 if (_flow->failing()) {
497 C->record_method_not_compilable(_flow->failure_reason());
498 #ifndef PRODUCT
499 if (PrintOpto && (Verbose || WizardMode)) {
500 tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
501 if (Verbose) {
502 method()->print();
503 method()->print_codes();
504 _flow->print();
505 }
506 }
507 #endif
508 }
509 _tf = C->tf(); // the OSR entry type is different
510 }
511
512 #ifdef ASSERT
513 if (depth() == 1) {
514 assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
515 if (C->tf() != tf()) {
516 MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
517 assert(C->env()->system_dictionary_modification_counter_changed(),
518 "Must invalidate if TypeFuncs differ");
519 }
520 } else {
521 assert(!this->is_osr_parse(), "no recursive OSR");
522 }
523 #endif
524
525 methods_parsed++;
526 #ifndef PRODUCT
527 // add method size here to guarantee that inlined methods are added too
528 if (TimeCompiler)
529 _total_bytes_compiled += method()->code_size();
530
531 show_parse_info();
532 #endif
533
534 if (failing()) {
535 if (log) log->done("parse");
536 return;
537 }
538
539 gvn().set_type(root(), root()->bottom_type());
540 gvn().transform(top());
541
542 // Import the results of the ciTypeFlow.
543 init_blocks();
544
545 // Merge point for all normal exits
546 build_exits();
547
548 // Setup the initial JVM state map.
549 SafePointNode* entry_map = create_entry_map();
550
551 // Check for bailouts during map initialization
552 if (failing() || entry_map == NULL) {
553 if (log) log->done("parse");
554 return;
555 }
556
557 Node_Notes* caller_nn = C->default_node_notes();
558 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
559 if (DebugInlinedCalls || depth() == 1) {
560 C->set_default_node_notes(make_node_notes(caller_nn));
561 }
562
563 if (is_osr_parse()) {
564 Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
565 entry_map->set_req(TypeFunc::Parms+0, top());
566 set_map(entry_map);
567 load_interpreter_state(osr_buf);
568 } else {
569 set_map(entry_map);
570 do_method_entry();
571 if (depth() == 1 && C->age_code()) {
572 decrement_age();
573 }
574 }
575 if (depth() == 1) {
576 // Add check to deoptimize the nmethod if RTM state was changed
577 rtm_deopt();
578 }
579
580 // Check for bailouts during method entry.
581 if (failing()) {
582 if (log) log->done("parse");
583 C->set_default_node_notes(caller_nn);
584 return;
585 }
586
587 entry_map = map(); // capture any changes performed by method setup code
588 assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
589
590 // We begin parsing as if we have just encountered a jump to the
591 // method entry.
592 Block* entry_block = start_block();
593 assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
594 set_map_clone(entry_map);
595 merge_common(entry_block, entry_block->next_path_num());
596
597 #ifndef PRODUCT
598 BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
599 set_parse_histogram( parse_histogram_obj );
600 #endif
601
602 // Parse all the basic blocks.
603 do_all_blocks();
604
605 C->set_default_node_notes(caller_nn);
606
607 // Check for bailouts during conversion to graph
608 if (failing()) {
609 if (log) log->done("parse");
610 return;
611 }
612
613 // Fix up all exiting control flow.
614 set_map(entry_map);
615 do_exits();
616
617 if (log) log->done("parse nodes='%d' live='%d' memory='" SIZE_FORMAT "'",
618 C->unique(), C->live_nodes(), C->node_arena()->used());
619 }
620
621 //---------------------------do_all_blocks-------------------------------------
622 void Parse::do_all_blocks() {
623 bool has_irreducible = flow()->has_irreducible_entry();
624
625 // Walk over all blocks in Reverse Post-Order.
626 while (true) {
627 bool progress = false;
628 for (int rpo = 0; rpo < block_count(); rpo++) {
629 Block* block = rpo_at(rpo);
630
631 if (block->is_parsed()) continue;
632
633 if (!block->is_merged()) {
634 // Dead block, no state reaches this block
635 continue;
636 }
637
638 // Prepare to parse this block.
639 load_state_from(block);
640
641 if (stopped()) {
642 // Block is dead.
643 continue;
644 }
645
646 blocks_parsed++;
647
648 progress = true;
649 if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
650 // Not all preds have been parsed. We must build phis everywhere.
651 // (Note that dead locals do not get phis built, ever.)
652 ensure_phis_everywhere();
653
654 if (block->is_SEL_head() &&
655 (UseLoopPredicate || LoopLimitCheck)) {
656 // Add predicate to single entry (not irreducible) loop head.
657 assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
658 // Need correct bci for predicate.
659 // It is fine to set it here since do_one_block() will set it anyway.
660 set_parse_bci(block->start());
661 add_predicate();
662 // Add new region for back branches.
663 int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
664 RegionNode *r = new (C) RegionNode(edges+1);
665 _gvn.set_type(r, Type::CONTROL);
666 record_for_igvn(r);
667 r->init_req(edges, control());
668 set_control(r);
669 // Add new phis.
670 ensure_phis_everywhere();
671 }
672
673 // Leave behind an undisturbed copy of the map, for future merges.
674 set_map(clone_map());
675 }
676
677 if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
678 // In the absence of irreducible loops, the Region and Phis
679 // associated with a merge that doesn't involve a backedge can
680 // be simplified now since the RPO parsing order guarantees
681 // that any path which was supposed to reach here has already
682 // been parsed or must be dead.
683 Node* c = control();
684 Node* result = _gvn.transform_no_reclaim(control());
685 if (c != result && TraceOptoParse) {
686 tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
687 }
688 if (result != top()) {
689 record_for_igvn(result);
690 }
691 }
692
693 // Parse the block.
694 do_one_block();
695
696 // Check for bailouts.
697 if (failing()) return;
698 }
699
700 // with irreducible loops multiple passes might be necessary to parse everything
701 if (!has_irreducible || !progress) {
702 break;
703 }
704 }
705
706 blocks_seen += block_count();
707
708 #ifndef PRODUCT
709 // Make sure there are no half-processed blocks remaining.
710 // Every remaining unprocessed block is dead and may be ignored now.
711 for (int rpo = 0; rpo < block_count(); rpo++) {
712 Block* block = rpo_at(rpo);
713 if (!block->is_parsed()) {
714 if (TraceOptoParse) {
715 tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
716 }
717 assert(!block->is_merged(), "no half-processed blocks");
718 }
719 }
720 #endif
721 }
722
723 //-------------------------------build_exits----------------------------------
724 // Build normal and exceptional exit merge points.
725 void Parse::build_exits() {
726 // make a clone of caller to prevent sharing of side-effects
727 _exits.set_map(_exits.clone_map());
728 _exits.clean_stack(_exits.sp());
729 _exits.sync_jvms();
730
731 RegionNode* region = new (C) RegionNode(1);
732 record_for_igvn(region);
733 gvn().set_type_bottom(region);
734 _exits.set_control(region);
735
736 // Note: iophi and memphi are not transformed until do_exits.
737 Node* iophi = new (C) PhiNode(region, Type::ABIO);
738 Node* memphi = new (C) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
739 gvn().set_type_bottom(iophi);
740 gvn().set_type_bottom(memphi);
741 _exits.set_i_o(iophi);
742 _exits.set_all_memory(memphi);
743
744 // Add a return value to the exit state. (Do not push it yet.)
745 if (tf()->range()->cnt() > TypeFunc::Parms) {
746 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
747 // Don't "bind" an unloaded return klass to the ret_phi. If the klass
748 // becomes loaded during the subsequent parsing, the loaded and unloaded
749 // types will not join when we transform and push in do_exits().
750 const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
751 if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
752 ret_type = TypeOopPtr::BOTTOM;
753 }
754 int ret_size = type2size[ret_type->basic_type()];
755 Node* ret_phi = new (C) PhiNode(region, ret_type);
756 gvn().set_type_bottom(ret_phi);
757 _exits.ensure_stack(ret_size);
758 assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
759 assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
760 _exits.set_argument(0, ret_phi); // here is where the parser finds it
761 // Note: ret_phi is not yet pushed, until do_exits.
762 }
763 }
764
765
766 //----------------------------build_start_state-------------------------------
767 // Construct a state which contains only the incoming arguments from an
768 // unknown caller. The method & bci will be NULL & InvocationEntryBci.
769 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
770 int arg_size = tf->domain()->cnt();
771 int max_size = MAX2(arg_size, (int)tf->range()->cnt());
772 JVMState* jvms = new (this) JVMState(max_size - TypeFunc::Parms);
773 SafePointNode* map = new (this) SafePointNode(max_size, NULL);
774 record_for_igvn(map);
775 assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
776 Node_Notes* old_nn = default_node_notes();
777 if (old_nn != NULL && has_method()) {
778 Node_Notes* entry_nn = old_nn->clone(this);
779 JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
780 entry_jvms->set_offsets(0);
781 entry_jvms->set_bci(entry_bci());
782 entry_nn->set_jvms(entry_jvms);
783 set_default_node_notes(entry_nn);
784 }
785 uint i;
786 for (i = 0; i < (uint)arg_size; i++) {
787 Node* parm = initial_gvn()->transform(new (this) ParmNode(start, i));
788 map->init_req(i, parm);
789 // Record all these guys for later GVN.
790 record_for_igvn(parm);
791 }
792 for (; i < map->req(); i++) {
793 map->init_req(i, top());
794 }
795 assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
796 set_default_node_notes(old_nn);
797 map->set_jvms(jvms);
798 jvms->set_map(map);
799 return jvms;
800 }
801
802 //-----------------------------make_node_notes---------------------------------
803 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
804 if (caller_nn == NULL) return NULL;
805 Node_Notes* nn = caller_nn->clone(C);
806 JVMState* caller_jvms = nn->jvms();
807 JVMState* jvms = new (C) JVMState(method(), caller_jvms);
808 jvms->set_offsets(0);
809 jvms->set_bci(_entry_bci);
810 nn->set_jvms(jvms);
811 return nn;
812 }
813
814
815 //--------------------------return_values--------------------------------------
816 void Compile::return_values(JVMState* jvms) {
817 GraphKit kit(jvms);
818 Node* ret = new (this) ReturnNode(TypeFunc::Parms,
819 kit.control(),
820 kit.i_o(),
821 kit.reset_memory(),
822 kit.frameptr(),
823 kit.returnadr());
824 // Add zero or 1 return values
825 int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
826 if (ret_size > 0) {
827 kit.inc_sp(-ret_size); // pop the return value(s)
828 kit.sync_jvms();
829 ret->add_req(kit.argument(0));
830 // Note: The second dummy edge is not needed by a ReturnNode.
831 }
832 // bind it to root
833 root()->add_req(ret);
834 record_for_igvn(ret);
835 initial_gvn()->transform_no_reclaim(ret);
836 }
837
838 //------------------------rethrow_exceptions-----------------------------------
839 // Bind all exception states in the list into a single RethrowNode.
840 void Compile::rethrow_exceptions(JVMState* jvms) {
841 GraphKit kit(jvms);
842 if (!kit.has_exceptions()) return; // nothing to generate
843 // Load my combined exception state into the kit, with all phis transformed:
844 SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
845 Node* ex_oop = kit.use_exception_state(ex_map);
846 RethrowNode* exit = new (this) RethrowNode(kit.control(),
847 kit.i_o(), kit.reset_memory(),
848 kit.frameptr(), kit.returnadr(),
849 // like a return but with exception input
850 ex_oop);
851 // bind to root
852 root()->add_req(exit);
853 record_for_igvn(exit);
854 initial_gvn()->transform_no_reclaim(exit);
855 }
856
857 //---------------------------do_exceptions-------------------------------------
858 // Process exceptions arising from the current bytecode.
859 // Send caught exceptions to the proper handler within this method.
860 // Unhandled exceptions feed into _exit.
861 void Parse::do_exceptions() {
862 if (!has_exceptions()) return;
863
864 if (failing()) {
865 // Pop them all off and throw them away.
866 while (pop_exception_state() != NULL) ;
867 return;
868 }
869
870 PreserveJVMState pjvms(this, false);
871
872 SafePointNode* ex_map;
873 while ((ex_map = pop_exception_state()) != NULL) {
874 if (!method()->has_exception_handlers()) {
875 // Common case: Transfer control outward.
876 // Doing it this early allows the exceptions to common up
877 // even between adjacent method calls.
878 throw_to_exit(ex_map);
879 } else {
880 // Have to look at the exception first.
881 assert(stopped(), "catch_inline_exceptions trashes the map");
882 catch_inline_exceptions(ex_map);
883 stop_and_kill_map(); // we used up this exception state; kill it
884 }
885 }
886
887 // We now return to our regularly scheduled program:
888 }
889
890 //---------------------------throw_to_exit-------------------------------------
891 // Merge the given map into an exception exit from this method.
892 // The exception exit will handle any unlocking of receiver.
893 // The ex_oop must be saved within the ex_map, unlike merge_exception.
894 void Parse::throw_to_exit(SafePointNode* ex_map) {
895 // Pop the JVMS to (a copy of) the caller.
896 GraphKit caller;
897 caller.set_map_clone(_caller->map());
898 caller.set_bci(_caller->bci());
899 caller.set_sp(_caller->sp());
900 // Copy out the standard machine state:
901 for (uint i = 0; i < TypeFunc::Parms; i++) {
902 caller.map()->set_req(i, ex_map->in(i));
903 }
904 // ...and the exception:
905 Node* ex_oop = saved_ex_oop(ex_map);
906 SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
907 // Finally, collect the new exception state in my exits:
908 _exits.add_exception_state(caller_ex_map);
909 }
910
911 //------------------------------do_exits---------------------------------------
912 void Parse::do_exits() {
913 set_parse_bci(InvocationEntryBci);
914
915 // Now peephole on the return bits
916 Node* region = _exits.control();
917 _exits.set_control(gvn().transform(region));
918
919 Node* iophi = _exits.i_o();
920 _exits.set_i_o(gvn().transform(iophi));
921
922 // Figure out if we need to emit the trailing barrier. The barrier is only
923 // needed in the constructors, and only in three cases:
924 //
925 // 1. The constructor wrote a final. The effects of all initializations
926 // must be committed to memory before any code after the constructor
927 // publishes the reference to the newly constructed object. Rather
928 // than wait for the publication, we simply block the writes here.
929 // Rather than put a barrier on only those writes which are required
930 // to complete, we force all writes to complete.
931 //
932 // 2. On PPC64, also add MemBarRelease for constructors which write
933 // volatile fields. As support_IRIW_for_not_multiple_copy_atomic_cpu
934 // is set on PPC64, no sync instruction is issued after volatile
935 // stores. We want to guarantee the same behavior as on platforms
936 // with total store order, although this is not required by the Java
937 // memory model. So as with finals, we add a barrier here.
938 //
939 // 3. Experimental VM option is used to force the barrier if any field
940 // was written out in the constructor.
941 //
942 // "All bets are off" unless the first publication occurs after a
943 // normal return from the constructor. We do not attempt to detect
944 // such unusual early publications. But no barrier is needed on
945 // exceptional returns, since they cannot publish normally.
946 //
947 if (method()->is_initializer() &&
948 (wrote_final() ||
949 PPC64_ONLY(wrote_volatile() ||)
950 (AlwaysSafeConstructors && wrote_fields()))) {
951 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
952 #ifndef PRODUCT
953 if (PrintOpto && (Verbose || WizardMode)) {
954 method()->print_name();
955 tty->print_cr(" writes finals and needs a memory barrier");
956 }
957 #endif
958 }
959
960 // Any method can write a @Stable field; insert memory barriers after
961 // those also. If there is a predecessor allocation node, bind the
962 // barrier there.
963 if (wrote_stable()) {
964 _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
965 #ifndef PRODUCT
966 if (PrintOpto && (Verbose || WizardMode)) {
967 method()->print_name();
968 tty->print_cr(" writes @Stable and needs a memory barrier");
969 }
970 #endif
971 }
972
973 for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
974 // transform each slice of the original memphi:
975 mms.set_memory(_gvn.transform(mms.memory()));
976 }
977
978 if (tf()->range()->cnt() > TypeFunc::Parms) {
979 const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
980 Node* ret_phi = _gvn.transform( _exits.argument(0) );
981 assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
982 _exits.push_node(ret_type->basic_type(), ret_phi);
983 }
984
985 // Note: Logic for creating and optimizing the ReturnNode is in Compile.
986
987 // Unlock along the exceptional paths.
988 // This is done late so that we can common up equivalent exceptions
989 // (e.g., null checks) arising from multiple points within this method.
990 // See GraphKit::add_exception_state, which performs the commoning.
991 bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
992
993 // record exit from a method if compiled while Dtrace is turned on.
994 if (do_synch || C->env()->dtrace_method_probes()) {
995 // First move the exception list out of _exits:
996 GraphKit kit(_exits.transfer_exceptions_into_jvms());
997 SafePointNode* normal_map = kit.map(); // keep this guy safe
998 // Now re-collect the exceptions into _exits:
999 SafePointNode* ex_map;
1000 while ((ex_map = kit.pop_exception_state()) != NULL) {
1001 Node* ex_oop = kit.use_exception_state(ex_map);
1002 // Force the exiting JVM state to have this method at InvocationEntryBci.
1003 // The exiting JVM state is otherwise a copy of the calling JVMS.
1004 JVMState* caller = kit.jvms();
1005 JVMState* ex_jvms = caller->clone_shallow(C);
1006 ex_jvms->set_map(kit.clone_map());
1007 ex_jvms->map()->set_jvms(ex_jvms);
1008 ex_jvms->set_bci( InvocationEntryBci);
1009 kit.set_jvms(ex_jvms);
1010 if (do_synch) {
1011 // Add on the synchronized-method box/object combo
1012 kit.map()->push_monitor(_synch_lock);
1013 // Unlock!
1014 kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1015 }
1016 if (C->env()->dtrace_method_probes()) {
1017 kit.make_dtrace_method_exit(method());
1018 }
1019 // Done with exception-path processing.
1020 ex_map = kit.make_exception_state(ex_oop);
1021 assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
1022 // Pop the last vestige of this method:
1023 ex_map->set_jvms(caller->clone_shallow(C));
1024 ex_map->jvms()->set_map(ex_map);
1025 _exits.push_exception_state(ex_map);
1026 }
1027 assert(_exits.map() == normal_map, "keep the same return state");
1028 }
1029
1030 {
1031 // Capture very early exceptions (receiver null checks) from caller JVMS
1032 GraphKit caller(_caller);
1033 SafePointNode* ex_map;
1034 while ((ex_map = caller.pop_exception_state()) != NULL) {
1035 _exits.add_exception_state(ex_map);
1036 }
1037 }
1038 }
1039
1040 //-----------------------------create_entry_map-------------------------------
1041 // Initialize our parser map to contain the types at method entry.
1042 // For OSR, the map contains a single RawPtr parameter.
1043 // Initial monitor locking for sync. methods is performed by do_method_entry.
1044 SafePointNode* Parse::create_entry_map() {
1045 // Check for really stupid bail-out cases.
1046 uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1047 if (len >= 32760) {
1048 C->record_method_not_compilable_all_tiers("too many local variables");
1049 return NULL;
1050 }
1051
1052 // If this is an inlined method, we may have to do a receiver null check.
1053 if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1054 GraphKit kit(_caller);
1055 kit.null_check_receiver_before_call(method());
1056 _caller = kit.transfer_exceptions_into_jvms();
1057 if (kit.stopped()) {
1058 _exits.add_exception_states_from(_caller);
1059 _exits.set_jvms(_caller);
1060 return NULL;
1061 }
1062 }
1063
1064 assert(method() != NULL, "parser must have a method");
1065
1066 // Create an initial safepoint to hold JVM state during parsing
1067 JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1068 set_map(new (C) SafePointNode(len, jvms));
1069 jvms->set_map(map());
1070 record_for_igvn(map());
1071 assert(jvms->endoff() == len, "correct jvms sizing");
1072
1073 SafePointNode* inmap = _caller->map();
1074 assert(inmap != NULL, "must have inmap");
1075
1076 uint i;
1077
1078 // Pass thru the predefined input parameters.
1079 for (i = 0; i < TypeFunc::Parms; i++) {
1080 map()->init_req(i, inmap->in(i));
1081 }
1082
1083 if (depth() == 1) {
1084 assert(map()->memory()->Opcode() == Op_Parm, "");
1085 // Insert the memory aliasing node
1086 set_all_memory(reset_memory());
1087 }
1088 assert(merged_memory(), "");
1089
1090 // Now add the locals which are initially bound to arguments:
1091 uint arg_size = tf()->domain()->cnt();
1092 ensure_stack(arg_size - TypeFunc::Parms); // OSR methods have funny args
1093 for (i = TypeFunc::Parms; i < arg_size; i++) {
1094 map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1095 }
1096
1097 // Clear out the rest of the map (locals and stack)
1098 for (i = arg_size; i < len; i++) {
1099 map()->init_req(i, top());
1100 }
1101
1102 SafePointNode* entry_map = stop();
1103 return entry_map;
1104 }
1105
1106 //-----------------------------do_method_entry--------------------------------
1107 // Emit any code needed in the pseudo-block before BCI zero.
1108 // The main thing to do is lock the receiver of a synchronized method.
1109 void Parse::do_method_entry() {
1110 set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1111 set_sp(0); // Java Stack Pointer
1112
1113 NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1114
1115 if (C->env()->dtrace_method_probes()) {
1116 make_dtrace_method_entry(method());
1117 }
1118
1119 // If the method is synchronized, we need to construct a lock node, attach
1120 // it to the Start node, and pin it there.
1121 if (method()->is_synchronized()) {
1122 // Insert a FastLockNode right after the Start which takes as arguments
1123 // the current thread pointer, the "this" pointer & the address of the
1124 // stack slot pair used for the lock. The "this" pointer is a projection
1125 // off the start node, but the locking spot has to be constructed by
1126 // creating a ConLNode of 0, and boxing it with a BoxLockNode. The BoxLockNode
1127 // becomes the second argument to the FastLockNode call. The
1128 // FastLockNode becomes the new control parent to pin it to the start.
1129
1130 // Setup Object Pointer
1131 Node *lock_obj = NULL;
1132 if(method()->is_static()) {
1133 ciInstance* mirror = _method->holder()->java_mirror();
1134 const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1135 lock_obj = makecon(t_lock);
1136 } else { // Else pass the "this" pointer,
1137 lock_obj = local(0); // which is Parm0 from StartNode
1138 }
1139 // Clear out dead values from the debug info.
1140 kill_dead_locals();
1141 // Build the FastLockNode
1142 _synch_lock = shared_lock(lock_obj);
1143 }
1144
1145 // Feed profiling data for parameters to the type system so it can
1146 // propagate it as speculative types
1147 record_profiled_parameters_for_speculation();
1148
1149 if (depth() == 1) {
1150 increment_and_test_invocation_counter(Tier2CompileThreshold);
1151 }
1152 }
1153
1154 //------------------------------init_blocks------------------------------------
1155 // Initialize our parser map to contain the types/monitors at method entry.
1156 void Parse::init_blocks() {
1157 // Create the blocks.
1158 _block_count = flow()->block_count();
1159 _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1160 Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
1161
1162 int rpo;
1163
1164 // Initialize the structs.
1165 for (rpo = 0; rpo < block_count(); rpo++) {
1166 Block* block = rpo_at(rpo);
1167 block->init_node(this, rpo);
1168 }
1169
1170 // Collect predecessor and successor information.
1171 for (rpo = 0; rpo < block_count(); rpo++) {
1172 Block* block = rpo_at(rpo);
1173 block->init_graph(this);
1174 }
1175 }
1176
1177 //-------------------------------init_node-------------------------------------
1178 void Parse::Block::init_node(Parse* outer, int rpo) {
1179 _flow = outer->flow()->rpo_at(rpo);
1180 _pred_count = 0;
1181 _preds_parsed = 0;
1182 _count = 0;
1183 assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1184 assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1185 assert(_live_locals.size() == 0, "sanity");
1186
1187 // entry point has additional predecessor
1188 if (flow()->is_start()) _pred_count++;
1189 assert(flow()->is_start() == (this == outer->start_block()), "");
1190 }
1191
1192 //-------------------------------init_graph------------------------------------
1193 void Parse::Block::init_graph(Parse* outer) {
1194 // Create the successor list for this parser block.
1195 GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1196 GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1197 int ns = tfs->length();
1198 int ne = tfe->length();
1199 _num_successors = ns;
1200 _all_successors = ns+ne;
1201 _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1202 int p = 0;
1203 for (int i = 0; i < ns+ne; i++) {
1204 ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1205 Block* block2 = outer->rpo_at(tf2->rpo());
1206 _successors[i] = block2;
1207
1208 // Accumulate pred info for the other block, too.
1209 if (i < ns) {
1210 block2->_pred_count++;
1211 } else {
1212 block2->_is_handler = true;
1213 }
1214
1215 #ifdef ASSERT
1216 // A block's successors must be distinguishable by BCI.
1217 // That is, no bytecode is allowed to branch to two different
1218 // clones of the same code location.
1219 for (int j = 0; j < i; j++) {
1220 Block* block1 = _successors[j];
1221 if (block1 == block2) continue; // duplicates are OK
1222 assert(block1->start() != block2->start(), "successors have unique bcis");
1223 }
1224 #endif
1225 }
1226
1227 // Note: We never call next_path_num along exception paths, so they
1228 // never get processed as "ready". Also, the input phis of exception
1229 // handlers get specially processed, so that
1230 }
1231
1232 //---------------------------successor_for_bci---------------------------------
1233 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1234 for (int i = 0; i < all_successors(); i++) {
1235 Block* block2 = successor_at(i);
1236 if (block2->start() == bci) return block2;
1237 }
1238 // We can actually reach here if ciTypeFlow traps out a block
1239 // due to an unloaded class, and concurrently with compilation the
1240 // class is then loaded, so that a later phase of the parser is
1241 // able to see more of the bytecode CFG. Or, the flow pass and
1242 // the parser can have a minor difference of opinion about executability
1243 // of bytecodes. For example, "obj.field = null" is executable even
1244 // if the field's type is an unloaded class; the flow pass used to
1245 // make a trap for such code.
1246 return NULL;
1247 }
1248
1249
1250 //-----------------------------stack_type_at-----------------------------------
1251 const Type* Parse::Block::stack_type_at(int i) const {
1252 return get_type(flow()->stack_type_at(i));
1253 }
1254
1255
1256 //-----------------------------local_type_at-----------------------------------
1257 const Type* Parse::Block::local_type_at(int i) const {
1258 // Make dead locals fall to bottom.
1259 if (_live_locals.size() == 0) {
1260 MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1261 // This bitmap can be zero length if we saw a breakpoint.
1262 // In such cases, pretend they are all live.
1263 ((Block*)this)->_live_locals = live_locals;
1264 }
1265 if (_live_locals.size() > 0 && !_live_locals.at(i))
1266 return Type::BOTTOM;
1267
1268 return get_type(flow()->local_type_at(i));
1269 }
1270
1271
1272 #ifndef PRODUCT
1273
1274 //----------------------------name_for_bc--------------------------------------
1275 // helper method for BytecodeParseHistogram
1276 static const char* name_for_bc(int i) {
1277 return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1278 }
1279
1280 //----------------------------BytecodeParseHistogram------------------------------------
1281 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1282 _parser = p;
1283 _compiler = c;
1284 if( ! _initialized ) { _initialized = true; reset(); }
1285 }
1286
1287 //----------------------------current_count------------------------------------
1288 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1289 switch( bph_type ) {
1290 case BPH_transforms: { return _parser->gvn().made_progress(); }
1291 case BPH_values: { return _parser->gvn().made_new_values(); }
1292 default: { ShouldNotReachHere(); return 0; }
1293 }
1294 }
1295
1296 //----------------------------initialized--------------------------------------
1297 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1298
1299 //----------------------------reset--------------------------------------------
1300 void Parse::BytecodeParseHistogram::reset() {
1301 int i = Bytecodes::number_of_codes;
1302 while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1303 }
1304
1305 //----------------------------set_initial_state--------------------------------
1306 // Record info when starting to parse one bytecode
1307 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1308 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1309 _initial_bytecode = bc;
1310 _initial_node_count = _compiler->unique();
1311 _initial_transforms = current_count(BPH_transforms);
1312 _initial_values = current_count(BPH_values);
1313 }
1314 }
1315
1316 //----------------------------record_change--------------------------------
1317 // Record results of parsing one bytecode
1318 void Parse::BytecodeParseHistogram::record_change() {
1319 if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1320 ++_bytecodes_parsed[_initial_bytecode];
1321 _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1322 _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1323 _new_values [_initial_bytecode] += (current_count(BPH_values) - _initial_values);
1324 }
1325 }
1326
1327
1328 //----------------------------print--------------------------------------------
1329 void Parse::BytecodeParseHistogram::print(float cutoff) {
1330 ResourceMark rm;
1331 // print profile
1332 int total = 0;
1333 int i = 0;
1334 for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1335 int abs_sum = 0;
1336 tty->cr(); //0123456789012345678901234567890123456789012345678901234567890123456789
1337 tty->print_cr("Histogram of %d parsed bytecodes:", total);
1338 if( total == 0 ) { return; }
1339 tty->cr();
1340 tty->print_cr("absolute: count of compiled bytecodes of this type");
1341 tty->print_cr("relative: percentage contribution to compiled nodes");
1342 tty->print_cr("nodes : Average number of nodes constructed per bytecode");
1343 tty->print_cr("rnodes : Significance towards total nodes constructed, (nodes*relative)");
1344 tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1345 tty->print_cr("values : Average number of node values improved per bytecode");
1346 tty->print_cr("name : Bytecode name");
1347 tty->cr();
1348 tty->print_cr(" absolute relative nodes rnodes transforms values name");
1349 tty->print_cr("----------------------------------------------------------------------");
1350 while (--i > 0) {
1351 int abs = _bytecodes_parsed[i];
1352 float rel = abs * 100.0F / total;
1353 float nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1354 float rnodes = _bytecodes_parsed[i] == 0 ? 0 : rel * nodes;
1355 float xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1356 float values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values [i])/_bytecodes_parsed[i];
1357 if (cutoff <= rel) {
1358 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));
1359 abs_sum += abs;
1360 }
1361 }
1362 tty->print_cr("----------------------------------------------------------------------");
1363 float rel_sum = abs_sum * 100.0F / total;
1364 tty->print_cr("%10d %7.2f%% (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1365 tty->print_cr("----------------------------------------------------------------------");
1366 tty->cr();
1367 }
1368 #endif
1369
1370 //----------------------------load_state_from----------------------------------
1371 // Load block/map/sp. But not do not touch iter/bci.
1372 void Parse::load_state_from(Block* block) {
1373 set_block(block);
1374 // load the block's JVM state:
1375 set_map(block->start_map());
1376 set_sp( block->start_sp());
1377 }
1378
1379
1380 //-----------------------------record_state------------------------------------
1381 void Parse::Block::record_state(Parse* p) {
1382 assert(!is_merged(), "can only record state once, on 1st inflow");
1383 assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1384 set_start_map(p->stop());
1385 }
1386
1387
1388 //------------------------------do_one_block-----------------------------------
1389 void Parse::do_one_block() {
1390 if (TraceOptoParse) {
1391 Block *b = block();
1392 int ns = b->num_successors();
1393 int nt = b->all_successors();
1394
1395 tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1396 block()->rpo(), block()->start(), block()->limit());
1397 for (int i = 0; i < nt; i++) {
1398 tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1399 }
1400 if (b->is_loop_head()) tty->print(" lphd");
1401 tty->cr();
1402 }
1403
1404 assert(block()->is_merged(), "must be merged before being parsed");
1405 block()->mark_parsed();
1406 ++_blocks_parsed;
1407
1408 // Set iterator to start of block.
1409 iter().reset_to_bci(block()->start());
1410
1411 CompileLog* log = C->log();
1412
1413 // Parse bytecodes
1414 while (!stopped() && !failing()) {
1415 iter().next();
1416
1417 // Learn the current bci from the iterator:
1418 set_parse_bci(iter().cur_bci());
1419
1420 if (bci() == block()->limit()) {
1421 // Do not walk into the next block until directed by do_all_blocks.
1422 merge(bci());
1423 break;
1424 }
1425 assert(bci() < block()->limit(), "bci still in block");
1426
1427 if (log != NULL) {
1428 // Output an optional context marker, to help place actions
1429 // that occur during parsing of this BC. If there is no log
1430 // output until the next context string, this context string
1431 // will be silently ignored.
1432 log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1433 }
1434
1435 if (block()->has_trap_at(bci())) {
1436 // We must respect the flow pass's traps, because it will refuse
1437 // to produce successors for trapping blocks.
1438 int trap_index = block()->flow()->trap_index();
1439 assert(trap_index != 0, "trap index must be valid");
1440 uncommon_trap(trap_index);
1441 break;
1442 }
1443
1444 NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1445
1446 #ifdef ASSERT
1447 int pre_bc_sp = sp();
1448 int inputs, depth;
1449 bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1450 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));
1451 #endif //ASSERT
1452
1453 do_one_bytecode();
1454
1455 assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1456 err_msg_res("incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth));
1457
1458 do_exceptions();
1459
1460 NOT_PRODUCT( parse_histogram()->record_change(); );
1461
1462 if (log != NULL)
1463 log->clear_context(); // skip marker if nothing was printed
1464
1465 // Fall into next bytecode. Each bytecode normally has 1 sequential
1466 // successor which is typically made ready by visiting this bytecode.
1467 // If the successor has several predecessors, then it is a merge
1468 // point, starts a new basic block, and is handled like other basic blocks.
1469 }
1470 }
1471
1472
1473 //------------------------------merge------------------------------------------
1474 void Parse::set_parse_bci(int bci) {
1475 set_bci(bci);
1476 Node_Notes* nn = C->default_node_notes();
1477 if (nn == NULL) return;
1478
1479 // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1480 if (!DebugInlinedCalls && depth() > 1) {
1481 return;
1482 }
1483
1484 // Update the JVMS annotation, if present.
1485 JVMState* jvms = nn->jvms();
1486 if (jvms != NULL && jvms->bci() != bci) {
1487 // Update the JVMS.
1488 jvms = jvms->clone_shallow(C);
1489 jvms->set_bci(bci);
1490 nn->set_jvms(jvms);
1491 }
1492 }
1493
1494 //------------------------------merge------------------------------------------
1495 // Merge the current mapping into the basic block starting at bci
1496 void Parse::merge(int target_bci) {
1497 Block* target = successor_for_bci(target_bci);
1498 if (target == NULL) { handle_missing_successor(target_bci); return; }
1499 assert(!target->is_ready(), "our arrival must be expected");
1500 int pnum = target->next_path_num();
1501 merge_common(target, pnum);
1502 }
1503
1504 //-------------------------merge_new_path--------------------------------------
1505 // Merge the current mapping into the basic block, using a new path
1506 void Parse::merge_new_path(int target_bci) {
1507 Block* target = successor_for_bci(target_bci);
1508 if (target == NULL) { handle_missing_successor(target_bci); return; }
1509 assert(!target->is_ready(), "new path into frozen graph");
1510 int pnum = target->add_new_path();
1511 merge_common(target, pnum);
1512 }
1513
1514 //-------------------------merge_exception-------------------------------------
1515 // Merge the current mapping into the basic block starting at bci
1516 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1517 void Parse::merge_exception(int target_bci) {
1518 assert(sp() == 1, "must have only the throw exception on the stack");
1519 Block* target = successor_for_bci(target_bci);
1520 if (target == NULL) { handle_missing_successor(target_bci); return; }
1521 assert(target->is_handler(), "exceptions are handled by special blocks");
1522 int pnum = target->add_new_path();
1523 merge_common(target, pnum);
1524 }
1525
1526 //--------------------handle_missing_successor---------------------------------
1527 void Parse::handle_missing_successor(int target_bci) {
1528 #ifndef PRODUCT
1529 Block* b = block();
1530 int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1531 tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1532 #endif
1533 ShouldNotReachHere();
1534 }
1535
1536 //--------------------------merge_common---------------------------------------
1537 void Parse::merge_common(Parse::Block* target, int pnum) {
1538 if (TraceOptoParse) {
1539 tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1540 }
1541
1542 // Zap extra stack slots to top
1543 assert(sp() == target->start_sp(), "");
1544 clean_stack(sp());
1545
1546 if (!target->is_merged()) { // No prior mapping at this bci
1547 if (TraceOptoParse) { tty->print(" with empty state"); }
1548
1549 // If this path is dead, do not bother capturing it as a merge.
1550 // It is "as if" we had 1 fewer predecessors from the beginning.
1551 if (stopped()) {
1552 if (TraceOptoParse) tty->print_cr(", but path is dead and doesn't count");
1553 return;
1554 }
1555
1556 // Record that a new block has been merged.
1557 ++_blocks_merged;
1558
1559 // Make a region if we know there are multiple or unpredictable inputs.
1560 // (Also, if this is a plain fall-through, we might see another region,
1561 // which must not be allowed into this block's map.)
1562 if (pnum > PhiNode::Input // Known multiple inputs.
1563 || target->is_handler() // These have unpredictable inputs.
1564 || target->is_loop_head() // Known multiple inputs
1565 || control()->is_Region()) { // We must hide this guy.
1566
1567 int current_bci = bci();
1568 set_parse_bci(target->start()); // Set target bci
1569 if (target->is_SEL_head()) {
1570 DEBUG_ONLY( target->mark_merged_backedge(block()); )
1571 if (target->start() == 0) {
1572 // Add loop predicate for the special case when
1573 // there are backbranches to the method entry.
1574 add_predicate();
1575 }
1576 }
1577 // Add a Region to start the new basic block. Phis will be added
1578 // later lazily.
1579 int edges = target->pred_count();
1580 if (edges < pnum) edges = pnum; // might be a new path!
1581 RegionNode *r = new (C) RegionNode(edges+1);
1582 gvn().set_type(r, Type::CONTROL);
1583 record_for_igvn(r);
1584 // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1585 // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1586 r->init_req(pnum, control());
1587 set_control(r);
1588 set_parse_bci(current_bci); // Restore bci
1589 }
1590
1591 // Convert the existing Parser mapping into a mapping at this bci.
1592 store_state_to(target);
1593 assert(target->is_merged(), "do not come here twice");
1594
1595 } else { // Prior mapping at this bci
1596 if (TraceOptoParse) { tty->print(" with previous state"); }
1597 #ifdef ASSERT
1598 if (target->is_SEL_head()) {
1599 target->mark_merged_backedge(block());
1600 }
1601 #endif
1602 // We must not manufacture more phis if the target is already parsed.
1603 bool nophi = target->is_parsed();
1604
1605 SafePointNode* newin = map();// Hang on to incoming mapping
1606 Block* save_block = block(); // Hang on to incoming block;
1607 load_state_from(target); // Get prior mapping
1608
1609 assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1610 assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1611 assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1612 assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1613
1614 // Iterate over my current mapping and the old mapping.
1615 // Where different, insert Phi functions.
1616 // Use any existing Phi functions.
1617 assert(control()->is_Region(), "must be merging to a region");
1618 RegionNode* r = control()->as_Region();
1619
1620 // Compute where to merge into
1621 // Merge incoming control path
1622 r->init_req(pnum, newin->control());
1623
1624 if (pnum == 1) { // Last merge for this Region?
1625 if (!block()->flow()->is_irreducible_entry()) {
1626 Node* result = _gvn.transform_no_reclaim(r);
1627 if (r != result && TraceOptoParse) {
1628 tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1629 }
1630 }
1631 record_for_igvn(r);
1632 }
1633
1634 // Update all the non-control inputs to map:
1635 assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1636 bool check_elide_phi = target->is_SEL_backedge(save_block);
1637 for (uint j = 1; j < newin->req(); j++) {
1638 Node* m = map()->in(j); // Current state of target.
1639 Node* n = newin->in(j); // Incoming change to target state.
1640 PhiNode* phi;
1641 if (m->is_Phi() && m->as_Phi()->region() == r)
1642 phi = m->as_Phi();
1643 else
1644 phi = NULL;
1645 if (m != n) { // Different; must merge
1646 switch (j) {
1647 // Frame pointer and Return Address never changes
1648 case TypeFunc::FramePtr:// Drop m, use the original value
1649 case TypeFunc::ReturnAdr:
1650 break;
1651 case TypeFunc::Memory: // Merge inputs to the MergeMem node
1652 assert(phi == NULL, "the merge contains phis, not vice versa");
1653 merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1654 continue;
1655 default: // All normal stuff
1656 if (phi == NULL) {
1657 const JVMState* jvms = map()->jvms();
1658 if (EliminateNestedLocks &&
1659 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1660 // BoxLock nodes are not commoning.
1661 // Use old BoxLock node as merged box.
1662 assert(newin->jvms()->is_monitor_box(j), "sanity");
1663 // This assert also tests that nodes are BoxLock.
1664 assert(BoxLockNode::same_slot(n, m), "sanity");
1665 C->gvn_replace_by(n, m);
1666 } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1667 phi = ensure_phi(j, nophi);
1668 }
1669 }
1670 break;
1671 }
1672 }
1673 // At this point, n might be top if:
1674 // - there is no phi (because TypeFlow detected a conflict), or
1675 // - the corresponding control edges is top (a dead incoming path)
1676 // It is a bug if we create a phi which sees a garbage value on a live path.
1677
1678 if (phi != NULL) {
1679 assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1680 assert(phi->region() == r, "");
1681 phi->set_req(pnum, n); // Then add 'n' to the merge
1682 if (pnum == PhiNode::Input) {
1683 // Last merge for this Phi.
1684 // So far, Phis have had a reasonable type from ciTypeFlow.
1685 // Now _gvn will join that with the meet of current inputs.
1686 // BOTTOM is never permissible here, 'cause pessimistically
1687 // Phis of pointers cannot lose the basic pointer type.
1688 debug_only(const Type* bt1 = phi->bottom_type());
1689 assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1690 map()->set_req(j, _gvn.transform_no_reclaim(phi));
1691 debug_only(const Type* bt2 = phi->bottom_type());
1692 assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1693 record_for_igvn(phi);
1694 }
1695 }
1696 } // End of for all values to be merged
1697
1698 if (pnum == PhiNode::Input &&
1699 !r->in(0)) { // The occasional useless Region
1700 assert(control() == r, "");
1701 set_control(r->nonnull_req());
1702 }
1703
1704 // newin has been subsumed into the lazy merge, and is now dead.
1705 set_block(save_block);
1706
1707 stop(); // done with this guy, for now
1708 }
1709
1710 if (TraceOptoParse) {
1711 tty->print_cr(" on path %d", pnum);
1712 }
1713
1714 // Done with this parser state.
1715 assert(stopped(), "");
1716 }
1717
1718
1719 //--------------------------merge_memory_edges---------------------------------
1720 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1721 // (nophi means we must not create phis, because we already parsed here)
1722 assert(n != NULL, "");
1723 // Merge the inputs to the MergeMems
1724 MergeMemNode* m = merged_memory();
1725
1726 assert(control()->is_Region(), "must be merging to a region");
1727 RegionNode* r = control()->as_Region();
1728
1729 PhiNode* base = NULL;
1730 MergeMemNode* remerge = NULL;
1731 for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1732 Node *p = mms.force_memory();
1733 Node *q = mms.memory2();
1734 if (mms.is_empty() && nophi) {
1735 // Trouble: No new splits allowed after a loop body is parsed.
1736 // Instead, wire the new split into a MergeMem on the backedge.
1737 // The optimizer will sort it out, slicing the phi.
1738 if (remerge == NULL) {
1739 assert(base != NULL, "");
1740 assert(base->in(0) != NULL, "should not be xformed away");
1741 remerge = MergeMemNode::make(C, base->in(pnum));
1742 gvn().set_type(remerge, Type::MEMORY);
1743 base->set_req(pnum, remerge);
1744 }
1745 remerge->set_memory_at(mms.alias_idx(), q);
1746 continue;
1747 }
1748 assert(!q->is_MergeMem(), "");
1749 PhiNode* phi;
1750 if (p != q) {
1751 phi = ensure_memory_phi(mms.alias_idx(), nophi);
1752 } else {
1753 if (p->is_Phi() && p->as_Phi()->region() == r)
1754 phi = p->as_Phi();
1755 else
1756 phi = NULL;
1757 }
1758 // Insert q into local phi
1759 if (phi != NULL) {
1760 assert(phi->region() == r, "");
1761 p = phi;
1762 phi->set_req(pnum, q);
1763 if (mms.at_base_memory()) {
1764 base = phi; // delay transforming it
1765 } else if (pnum == 1) {
1766 record_for_igvn(phi);
1767 p = _gvn.transform_no_reclaim(phi);
1768 }
1769 mms.set_memory(p);// store back through the iterator
1770 }
1771 }
1772 // Transform base last, in case we must fiddle with remerging.
1773 if (base != NULL && pnum == 1) {
1774 record_for_igvn(base);
1775 m->set_base_memory( _gvn.transform_no_reclaim(base) );
1776 }
1777 }
1778
1779
1780 //------------------------ensure_phis_everywhere-------------------------------
1781 void Parse::ensure_phis_everywhere() {
1782 ensure_phi(TypeFunc::I_O);
1783
1784 // Ensure a phi on all currently known memories.
1785 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1786 ensure_memory_phi(mms.alias_idx());
1787 debug_only(mms.set_memory()); // keep the iterator happy
1788 }
1789
1790 // Note: This is our only chance to create phis for memory slices.
1791 // If we miss a slice that crops up later, it will have to be
1792 // merged into the base-memory phi that we are building here.
1793 // Later, the optimizer will comb out the knot, and build separate
1794 // phi-loops for each memory slice that matters.
1795
1796 // Monitors must nest nicely and not get confused amongst themselves.
1797 // Phi-ify everything up to the monitors, though.
1798 uint monoff = map()->jvms()->monoff();
1799 uint nof_monitors = map()->jvms()->nof_monitors();
1800
1801 assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1802 bool check_elide_phi = block()->is_SEL_head();
1803 for (uint i = TypeFunc::Parms; i < monoff; i++) {
1804 if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1805 ensure_phi(i);
1806 }
1807 }
1808
1809 // Even monitors need Phis, though they are well-structured.
1810 // This is true for OSR methods, and also for the rare cases where
1811 // a monitor object is the subject of a replace_in_map operation.
1812 // See bugs 4426707 and 5043395.
1813 for (uint m = 0; m < nof_monitors; m++) {
1814 ensure_phi(map()->jvms()->monitor_obj_offset(m));
1815 }
1816 }
1817
1818
1819 //-----------------------------add_new_path------------------------------------
1820 // Add a previously unaccounted predecessor to this block.
1821 int Parse::Block::add_new_path() {
1822 // If there is no map, return the lowest unused path number.
1823 if (!is_merged()) return pred_count()+1; // there will be a map shortly
1824
1825 SafePointNode* map = start_map();
1826 if (!map->control()->is_Region())
1827 return pred_count()+1; // there may be a region some day
1828 RegionNode* r = map->control()->as_Region();
1829
1830 // Add new path to the region.
1831 uint pnum = r->req();
1832 r->add_req(NULL);
1833
1834 for (uint i = 1; i < map->req(); i++) {
1835 Node* n = map->in(i);
1836 if (i == TypeFunc::Memory) {
1837 // Ensure a phi on all currently known memories.
1838 for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1839 Node* phi = mms.memory();
1840 if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1841 assert(phi->req() == pnum, "must be same size as region");
1842 phi->add_req(NULL);
1843 }
1844 }
1845 } else {
1846 if (n->is_Phi() && n->as_Phi()->region() == r) {
1847 assert(n->req() == pnum, "must be same size as region");
1848 n->add_req(NULL);
1849 }
1850 }
1851 }
1852
1853 return pnum;
1854 }
1855
1856 //------------------------------ensure_phi-------------------------------------
1857 // Turn the idx'th entry of the current map into a Phi
1858 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1859 SafePointNode* map = this->map();
1860 Node* region = map->control();
1861 assert(region->is_Region(), "");
1862
1863 Node* o = map->in(idx);
1864 assert(o != NULL, "");
1865
1866 if (o == top()) return NULL; // TOP always merges into TOP
1867
1868 if (o->is_Phi() && o->as_Phi()->region() == region) {
1869 return o->as_Phi();
1870 }
1871
1872 // Now use a Phi here for merging
1873 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1874 const JVMState* jvms = map->jvms();
1875 const Type* t;
1876 if (jvms->is_loc(idx)) {
1877 t = block()->local_type_at(idx - jvms->locoff());
1878 } else if (jvms->is_stk(idx)) {
1879 t = block()->stack_type_at(idx - jvms->stkoff());
1880 } else if (jvms->is_mon(idx)) {
1881 assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1882 t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1883 } else if ((uint)idx < TypeFunc::Parms) {
1884 t = o->bottom_type(); // Type::RETURN_ADDRESS or such-like.
1885 } else {
1886 assert(false, "no type information for this phi");
1887 }
1888
1889 // If the type falls to bottom, then this must be a local that
1890 // is mixing ints and oops or some such. Forcing it to top
1891 // makes it go dead.
1892 if (t == Type::BOTTOM) {
1893 map->set_req(idx, top());
1894 return NULL;
1895 }
1896
1897 // Do not create phis for top either.
1898 // A top on a non-null control flow must be an unused even after the.phi.
1899 if (t == Type::TOP || t == Type::HALF) {
1900 map->set_req(idx, top());
1901 return NULL;
1902 }
1903
1904 PhiNode* phi = PhiNode::make(region, o, t);
1905 gvn().set_type(phi, t);
1906 if (C->do_escape_analysis()) record_for_igvn(phi);
1907 map->set_req(idx, phi);
1908 return phi;
1909 }
1910
1911 //--------------------------ensure_memory_phi----------------------------------
1912 // Turn the idx'th slice of the current memory into a Phi
1913 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1914 MergeMemNode* mem = merged_memory();
1915 Node* region = control();
1916 assert(region->is_Region(), "");
1917
1918 Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1919 assert(o != NULL && o != top(), "");
1920
1921 PhiNode* phi;
1922 if (o->is_Phi() && o->as_Phi()->region() == region) {
1923 phi = o->as_Phi();
1924 if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1925 // clone the shared base memory phi to make a new memory split
1926 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1927 const Type* t = phi->bottom_type();
1928 const TypePtr* adr_type = C->get_adr_type(idx);
1929 phi = phi->slice_memory(adr_type);
1930 gvn().set_type(phi, t);
1931 }
1932 return phi;
1933 }
1934
1935 // Now use a Phi here for merging
1936 assert(!nocreate, "Cannot build a phi for a block already parsed.");
1937 const Type* t = o->bottom_type();
1938 const TypePtr* adr_type = C->get_adr_type(idx);
1939 phi = PhiNode::make(region, o, t, adr_type);
1940 gvn().set_type(phi, t);
1941 if (idx == Compile::AliasIdxBot)
1942 mem->set_base_memory(phi);
1943 else
1944 mem->set_memory_at(idx, phi);
1945 return phi;
1946 }
1947
1948 //------------------------------call_register_finalizer-----------------------
1949 // Check the klass of the receiver and call register_finalizer if the
1950 // class need finalization.
1951 void Parse::call_register_finalizer() {
1952 Node* receiver = local(0);
1953 assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1954 "must have non-null instance type");
1955
1956 const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
1957 if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
1958 // The type isn't known exactly so see if CHA tells us anything.
1959 ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
1960 if (!Dependencies::has_finalizable_subclass(ik)) {
1961 // No finalizable subclasses so skip the dynamic check.
1962 C->dependencies()->assert_has_no_finalizable_subclasses(ik);
1963 return;
1964 }
1965 }
1966
1967 // Insert a dynamic test for whether the instance needs
1968 // finalization. In general this will fold up since the concrete
1969 // class is often visible so the access flags are constant.
1970 Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
1971 Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
1972
1973 Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
1974 Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT, MemNode::unordered);
1975
1976 Node* mask = _gvn.transform(new (C) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
1977 Node* check = _gvn.transform(new (C) CmpINode(mask, intcon(0)));
1978 Node* test = _gvn.transform(new (C) BoolNode(check, BoolTest::ne));
1979
1980 IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
1981
1982 RegionNode* result_rgn = new (C) RegionNode(3);
1983 record_for_igvn(result_rgn);
1984
1985 Node *skip_register = _gvn.transform(new (C) IfFalseNode(iff));
1986 result_rgn->init_req(1, skip_register);
1987
1988 Node *needs_register = _gvn.transform(new (C) IfTrueNode(iff));
1989 set_control(needs_register);
1990 if (stopped()) {
1991 // There is no slow path.
1992 result_rgn->init_req(2, top());
1993 } else {
1994 Node *call = make_runtime_call(RC_NO_LEAF,
1995 OptoRuntime::register_finalizer_Type(),
1996 OptoRuntime::register_finalizer_Java(),
1997 NULL, TypePtr::BOTTOM,
1998 receiver);
1999 make_slow_call_ex(call, env()->Throwable_klass(), true);
2000
2001 Node* fast_io = call->in(TypeFunc::I_O);
2002 Node* fast_mem = call->in(TypeFunc::Memory);
2003 // These two phis are pre-filled with copies of of the fast IO and Memory
2004 Node* io_phi = PhiNode::make(result_rgn, fast_io, Type::ABIO);
2005 Node* mem_phi = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
2006
2007 result_rgn->init_req(2, control());
2008 io_phi ->init_req(2, i_o());
2009 mem_phi ->init_req(2, reset_memory());
2010
2011 set_all_memory( _gvn.transform(mem_phi) );
2012 set_i_o( _gvn.transform(io_phi) );
2013 }
2014
2015 set_control( _gvn.transform(result_rgn) );
2016 }
2017
2018 // Add check to deoptimize if RTM state is not ProfileRTM
2019 void Parse::rtm_deopt() {
2020 #if INCLUDE_RTM_OPT
2021 if (C->profile_rtm()) {
2022 assert(C->method() != NULL, "only for normal compilations");
2023 assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
2024 assert(depth() == 1, "generate check only for main compiled method");
2025
2026 // Set starting bci for uncommon trap.
2027 set_parse_bci(is_osr_parse() ? osr_bci() : 0);
2028
2029 // Load the rtm_state from the MethodData.
2030 const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
2031 Node* mdo = makecon(adr_type);
2032 int offset = MethodData::rtm_state_offset_in_bytes();
2033 Node* adr_node = basic_plus_adr(mdo, mdo, offset);
2034 Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2035
2036 // Separate Load from Cmp by Opaque.
2037 // In expand_macro_nodes() it will be replaced either
2038 // with this load when there are locks in the code
2039 // or with ProfileRTM (cmp->in(2)) otherwise so that
2040 // the check will fold.
2041 Node* profile_state = makecon(TypeInt::make(ProfileRTM));
2042 Node* opq = _gvn.transform( new (C) Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
2043 Node* chk = _gvn.transform( new (C) CmpINode(opq, profile_state) );
2044 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
2045 // Branch to failure if state was changed
2046 { BuildCutout unless(this, tst, PROB_ALWAYS);
2047 uncommon_trap(Deoptimization::Reason_rtm_state_change,
2048 Deoptimization::Action_make_not_entrant);
2049 }
2050 }
2051 #endif
2052 }
2053
2054 void Parse::decrement_age() {
2055 MethodCounters* mc = method()->ensure_method_counters();
2056 if (mc == NULL) {
2057 C->record_failure("Must have MCs");
2058 return;
2059 }
2060 assert(!is_osr_parse(), "Not doing this for OSRs");
2061
2062 // Set starting bci for uncommon trap.
2063 set_parse_bci(0);
2064
2065 const TypePtr* adr_type = TypeRawPtr::make((address)mc);
2066 Node* mc_adr = makecon(adr_type);
2067 Node* cnt_adr = basic_plus_adr(mc_adr, mc_adr, in_bytes(MethodCounters::nmethod_age_offset()));
2068 Node* cnt = make_load(control(), cnt_adr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2069 Node* decr = _gvn.transform(new (C) SubINode(cnt, makecon(TypeInt::ONE)));
2070 store_to_memory(control(), cnt_adr, decr, T_INT, adr_type, MemNode::unordered);
2071 Node *chk = _gvn.transform(new (C) CmpINode(decr, makecon(TypeInt::ZERO)));
2072 Node* tst = _gvn.transform(new (C) BoolNode(chk, BoolTest::gt));
2073 { BuildCutout unless(this, tst, PROB_ALWAYS);
2074 uncommon_trap(Deoptimization::Reason_tenured,
2075 Deoptimization::Action_make_not_entrant);
2076 }
2077 }
2078
2079 //------------------------------return_current---------------------------------
2080 // Append current _map to _exit_return
2081 void Parse::return_current(Node* value) {
2082 if (RegisterFinalizersAtInit &&
2083 method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2084 call_register_finalizer();
2085 }
2086
2087 // Do not set_parse_bci, so that return goo is credited to the return insn.
2088 set_bci(InvocationEntryBci);
2089 if (method()->is_synchronized() && GenerateSynchronizationCode) {
2090 shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2091 }
2092 if (C->env()->dtrace_method_probes()) {
2093 make_dtrace_method_exit(method());
2094 }
2095 SafePointNode* exit_return = _exits.map();
2096 exit_return->in( TypeFunc::Control )->add_req( control() );
2097 exit_return->in( TypeFunc::I_O )->add_req( i_o () );
2098 Node *mem = exit_return->in( TypeFunc::Memory );
2099 for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2100 if (mms.is_empty()) {
2101 // get a copy of the base memory, and patch just this one input
2102 const TypePtr* adr_type = mms.adr_type(C);
2103 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2104 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2105 gvn().set_type_bottom(phi);
2106 phi->del_req(phi->req()-1); // prepare to re-patch
2107 mms.set_memory(phi);
2108 }
2109 mms.memory()->add_req(mms.memory2());
2110 }
2111
2112 // frame pointer is always same, already captured
2113 if (value != NULL) {
2114 // If returning oops to an interface-return, there is a silent free
2115 // cast from oop to interface allowed by the Verifier. Make it explicit
2116 // here.
2117 Node* phi = _exits.argument(0);
2118 const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2119 if( tr && tr->klass()->is_loaded() &&
2120 tr->klass()->is_interface() ) {
2121 const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2122 if (tp && tp->klass()->is_loaded() &&
2123 !tp->klass()->is_interface()) {
2124 // sharpen the type eagerly; this eases certain assert checking
2125 if (tp->higher_equal(TypeInstPtr::NOTNULL))
2126 tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2127 value = _gvn.transform(new (C) CheckCastPPNode(0,value,tr));
2128 }
2129 }
2130 phi->add_req(value);
2131 }
2132
2133 stop_and_kill_map(); // This CFG path dies here
2134 }
2135
2136
2137 //------------------------------add_safepoint----------------------------------
2138 void Parse::add_safepoint() {
2139 // See if we can avoid this safepoint. No need for a SafePoint immediately
2140 // after a Call (except Leaf Call) or another SafePoint.
2141 Node *proj = control();
2142 bool add_poll_param = SafePointNode::needs_polling_address_input();
2143 uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2144 if( proj->is_Proj() ) {
2145 Node *n0 = proj->in(0);
2146 if( n0->is_Catch() ) {
2147 n0 = n0->in(0)->in(0);
2148 assert( n0->is_Call(), "expect a call here" );
2149 }
2150 if( n0->is_Call() ) {
2151 if( n0->as_Call()->guaranteed_safepoint() )
2152 return;
2153 } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2154 return;
2155 }
2156 }
2157
2158 // Clear out dead values from the debug info.
2159 kill_dead_locals();
2160
2161 // Clone the JVM State
2162 SafePointNode *sfpnt = new (C) SafePointNode(parms, NULL);
2163
2164 // Capture memory state BEFORE a SafePoint. Since we can block at a
2165 // SafePoint we need our GC state to be safe; i.e. we need all our current
2166 // write barriers (card marks) to not float down after the SafePoint so we
2167 // must read raw memory. Likewise we need all oop stores to match the card
2168 // marks. If deopt can happen, we need ALL stores (we need the correct JVM
2169 // state on a deopt).
2170
2171 // We do not need to WRITE the memory state after a SafePoint. The control
2172 // edge will keep card-marks and oop-stores from floating up from below a
2173 // SafePoint and our true dependency added here will keep them from floating
2174 // down below a SafePoint.
2175
2176 // Clone the current memory state
2177 Node* mem = MergeMemNode::make(C, map()->memory());
2178
2179 mem = _gvn.transform(mem);
2180
2181 // Pass control through the safepoint
2182 sfpnt->init_req(TypeFunc::Control , control());
2183 // Fix edges normally used by a call
2184 sfpnt->init_req(TypeFunc::I_O , top() );
2185 sfpnt->init_req(TypeFunc::Memory , mem );
2186 sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2187 sfpnt->init_req(TypeFunc::FramePtr , top() );
2188
2189 // Create a node for the polling address
2190 if( add_poll_param ) {
2191 Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
2192 sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2193 }
2194
2195 // Fix up the JVM State edges
2196 add_safepoint_edges(sfpnt);
2197 Node *transformed_sfpnt = _gvn.transform(sfpnt);
2198 set_control(transformed_sfpnt);
2199
2200 // Provide an edge from root to safepoint. This makes the safepoint
2201 // appear useful until the parse has completed.
2202 if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2203 assert(C->root() != NULL, "Expect parse is still valid");
2204 C->root()->add_prec(transformed_sfpnt);
2205 }
2206 }
2207
2208 #ifndef PRODUCT
2209 //------------------------show_parse_info--------------------------------------
2210 void Parse::show_parse_info() {
2211 InlineTree* ilt = NULL;
2212 if (C->ilt() != NULL) {
2213 JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2214 ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2215 }
2216 if (PrintCompilation && Verbose) {
2217 if (depth() == 1) {
2218 if( ilt->count_inlines() ) {
2219 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2220 ilt->count_inline_bcs());
2221 tty->cr();
2222 }
2223 } else {
2224 if (method()->is_synchronized()) tty->print("s");
2225 if (method()->has_exception_handlers()) tty->print("!");
2226 // Check this is not the final compiled version
2227 if (C->trap_can_recompile()) {
2228 tty->print("-");
2229 } else {
2230 tty->print(" ");
2231 }
2232 method()->print_short_name();
2233 if (is_osr_parse()) {
2234 tty->print(" @ %d", osr_bci());
2235 }
2236 tty->print(" (%d bytes)",method()->code_size());
2237 if (ilt->count_inlines()) {
2238 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2239 ilt->count_inline_bcs());
2240 }
2241 tty->cr();
2242 }
2243 }
2244 if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2245 // Print that we succeeded; suppress this message on the first osr parse.
2246
2247 if (method()->is_synchronized()) tty->print("s");
2248 if (method()->has_exception_handlers()) tty->print("!");
2249 // Check this is not the final compiled version
2250 if (C->trap_can_recompile() && depth() == 1) {
2251 tty->print("-");
2252 } else {
2253 tty->print(" ");
2254 }
2255 if( depth() != 1 ) { tty->print(" "); } // missing compile count
2256 for (int i = 1; i < depth(); ++i) { tty->print(" "); }
2257 method()->print_short_name();
2258 if (is_osr_parse()) {
2259 tty->print(" @ %d", osr_bci());
2260 }
2261 if (ilt->caller_bci() != -1) {
2262 tty->print(" @ %d", ilt->caller_bci());
2263 }
2264 tty->print(" (%d bytes)",method()->code_size());
2265 if (ilt->count_inlines()) {
2266 tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2267 ilt->count_inline_bcs());
2268 }
2269 tty->cr();
2270 }
2271 }
2272
2273
2274 //------------------------------dump-------------------------------------------
2275 // Dump information associated with the bytecodes of current _method
2276 void Parse::dump() {
2277 if( method() != NULL ) {
2278 // Iterate over bytecodes
2279 ciBytecodeStream iter(method());
2280 for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2281 dump_bci( iter.cur_bci() );
2282 tty->cr();
2283 }
2284 }
2285 }
2286
2287 // Dump information associated with a byte code index, 'bci'
2288 void Parse::dump_bci(int bci) {
2289 // Output info on merge-points, cloning, and within _jsr..._ret
2290 // NYI
2291 tty->print(" bci:%d", bci);
2292 }
2293
2294 #endif