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