1 /*
2 * Copyright (c) 2005, 2015, 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 "ci/bcEscapeAnalyzer.hpp"
27 #include "compiler/compileLog.hpp"
28 #include "libadt/vectset.hpp"
29 #include "memory/allocation.hpp"
30 #include "opto/c2compiler.hpp"
31 #include "opto/arraycopynode.hpp"
32 #include "opto/callnode.hpp"
33 #include "opto/cfgnode.hpp"
34 #include "opto/compile.hpp"
35 #include "opto/escape.hpp"
36 #include "opto/phaseX.hpp"
37 #include "opto/movenode.hpp"
38 #include "opto/rootnode.hpp"
39
40 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) :
41 _nodes(C->comp_arena(), C->unique(), C->unique(), NULL),
42 _in_worklist(C->comp_arena()),
43 _next_pidx(0),
44 _collecting(true),
45 _verify(false),
46 _compile(C),
47 _igvn(igvn),
48 _node_map(C->comp_arena()) {
49 // Add unknown java object.
50 add_java_object(C->top(), PointsToNode::GlobalEscape);
51 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject();
52 // Add ConP(#NULL) and ConN(#NULL) nodes.
53 Node* oop_null = igvn->zerocon(T_OBJECT);
54 assert(oop_null->_idx < nodes_size(), "should be created already");
55 add_java_object(oop_null, PointsToNode::NoEscape);
56 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject();
57 if (UseCompressedOops) {
58 Node* noop_null = igvn->zerocon(T_NARROWOOP);
59 assert(noop_null->_idx < nodes_size(), "should be created already");
60 map_ideal_node(noop_null, null_obj);
61 }
62 _pcmp_neq = NULL; // Should be initialized
63 _pcmp_eq = NULL;
64 }
65
66 bool ConnectionGraph::has_candidates(Compile *C) {
67 // EA brings benefits only when the code has allocations and/or locks which
68 // are represented by ideal Macro nodes.
69 int cnt = C->macro_count();
70 for (int i = 0; i < cnt; i++) {
71 Node *n = C->macro_node(i);
72 if (n->is_Allocate())
73 return true;
74 if (n->is_Lock()) {
75 Node* obj = n->as_Lock()->obj_node()->uncast();
76 if (!(obj->is_Parm() || obj->is_Con()))
77 return true;
78 }
79 if (n->is_CallStaticJava() &&
80 n->as_CallStaticJava()->is_boxing_method()) {
81 return true;
82 }
83 }
84 return false;
85 }
86
87 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
88 Compile::TracePhase tp("escapeAnalysis", &Phase::timers[Phase::_t_escapeAnalysis]);
89 ResourceMark rm;
90
91 // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction
92 // to create space for them in ConnectionGraph::_nodes[].
93 Node* oop_null = igvn->zerocon(T_OBJECT);
94 Node* noop_null = igvn->zerocon(T_NARROWOOP);
95 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn);
96 // Perform escape analysis
97 if (congraph->compute_escape()) {
98 // There are non escaping objects.
99 C->set_congraph(congraph);
100 }
101 // Cleanup.
102 if (oop_null->outcnt() == 0)
103 igvn->hash_delete(oop_null);
104 if (noop_null->outcnt() == 0)
105 igvn->hash_delete(noop_null);
106 }
107
108 bool ConnectionGraph::compute_escape() {
109 Compile* C = _compile;
110 PhaseGVN* igvn = _igvn;
111
112 // Worklists used by EA.
113 Unique_Node_List delayed_worklist;
114 GrowableArray<Node*> alloc_worklist;
115 GrowableArray<Node*> ptr_cmp_worklist;
116 GrowableArray<Node*> storestore_worklist;
117 GrowableArray<ArrayCopyNode*> arraycopy_worklist;
118 GrowableArray<PointsToNode*> ptnodes_worklist;
119 GrowableArray<JavaObjectNode*> java_objects_worklist;
120 GrowableArray<JavaObjectNode*> non_escaped_worklist;
121 GrowableArray<FieldNode*> oop_fields_worklist;
122 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; )
123
124 { Compile::TracePhase tp("connectionGraph", &Phase::timers[Phase::_t_connectionGraph]);
125
126 // 1. Populate Connection Graph (CG) with PointsTo nodes.
127 ideal_nodes.map(C->live_nodes(), NULL); // preallocate space
128 // Initialize worklist
129 if (C->root() != NULL) {
130 ideal_nodes.push(C->root());
131 }
132 // Processed ideal nodes are unique on ideal_nodes list
133 // but several ideal nodes are mapped to the phantom_obj.
134 // To avoid duplicated entries on the following worklists
135 // add the phantom_obj only once to them.
136 ptnodes_worklist.append(phantom_obj);
137 java_objects_worklist.append(phantom_obj);
138 for( uint next = 0; next < ideal_nodes.size(); ++next ) {
139 Node* n = ideal_nodes.at(next);
140 // Create PointsTo nodes and add them to Connection Graph. Called
141 // only once per ideal node since ideal_nodes is Unique_Node list.
142 add_node_to_connection_graph(n, &delayed_worklist);
143 PointsToNode* ptn = ptnode_adr(n->_idx);
144 if (ptn != NULL && ptn != phantom_obj) {
145 ptnodes_worklist.append(ptn);
146 if (ptn->is_JavaObject()) {
147 java_objects_worklist.append(ptn->as_JavaObject());
148 if ((n->is_Allocate() || n->is_CallStaticJava()) &&
149 (ptn->escape_state() < PointsToNode::GlobalEscape)) {
150 // Only allocations and java static calls results are interesting.
151 non_escaped_worklist.append(ptn->as_JavaObject());
152 }
153 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) {
154 oop_fields_worklist.append(ptn->as_Field());
155 }
156 }
157 if (n->is_MergeMem()) {
158 // Collect all MergeMem nodes to add memory slices for
159 // scalar replaceable objects in split_unique_types().
160 _mergemem_worklist.append(n->as_MergeMem());
161 } else if (OptimizePtrCompare && n->is_Cmp() &&
162 (n->Opcode() == Op_CmpP || n->Opcode() == Op_CmpN)) {
163 // Collect compare pointers nodes.
164 ptr_cmp_worklist.append(n);
165 } else if (n->is_MemBarStoreStore()) {
166 // Collect all MemBarStoreStore nodes so that depending on the
167 // escape status of the associated Allocate node some of them
168 // may be eliminated.
169 storestore_worklist.append(n);
170 } else if (n->is_MemBar() && (n->Opcode() == Op_MemBarRelease) &&
171 (n->req() > MemBarNode::Precedent)) {
172 record_for_optimizer(n);
173 #ifdef ASSERT
174 } else if (n->is_AddP()) {
175 // Collect address nodes for graph verification.
176 addp_worklist.append(n);
177 #endif
178 } else if (n->is_ArrayCopy()) {
179 // Keep a list of ArrayCopy nodes so if one of its input is non
180 // escaping, we can record a unique type
181 arraycopy_worklist.append(n->as_ArrayCopy());
182 }
183 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
184 Node* m = n->fast_out(i); // Get user
185 ideal_nodes.push(m);
186 }
187 }
188 if (non_escaped_worklist.length() == 0) {
189 _collecting = false;
190 return false; // Nothing to do.
191 }
192 // Add final simple edges to graph.
193 while(delayed_worklist.size() > 0) {
194 Node* n = delayed_worklist.pop();
195 add_final_edges(n);
196 }
197 int ptnodes_length = ptnodes_worklist.length();
198
199 #ifdef ASSERT
200 if (VerifyConnectionGraph) {
201 // Verify that no new simple edges could be created and all
202 // local vars has edges.
203 _verify = true;
204 for (int next = 0; next < ptnodes_length; ++next) {
205 PointsToNode* ptn = ptnodes_worklist.at(next);
206 add_final_edges(ptn->ideal_node());
207 if (ptn->is_LocalVar() && ptn->edge_count() == 0) {
208 ptn->dump();
209 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity");
210 }
211 }
212 _verify = false;
213 }
214 #endif
215 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes
216 // processing, calls to CI to resolve symbols (types, fields, methods)
217 // referenced in bytecode. During symbol resolution VM may throw
218 // an exception which CI cleans and converts to compilation failure.
219 if (C->failing()) return false;
220
221 // 2. Finish Graph construction by propagating references to all
222 // java objects through graph.
223 if (!complete_connection_graph(ptnodes_worklist, non_escaped_worklist,
224 java_objects_worklist, oop_fields_worklist)) {
225 // All objects escaped or hit time or iterations limits.
226 _collecting = false;
227 return false;
228 }
229
230 // 3. Adjust scalar_replaceable state of nonescaping objects and push
231 // scalar replaceable allocations on alloc_worklist for processing
232 // in split_unique_types().
233 int non_escaped_length = non_escaped_worklist.length();
234 for (int next = 0; next < non_escaped_length; next++) {
235 JavaObjectNode* ptn = non_escaped_worklist.at(next);
236 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape);
237 Node* n = ptn->ideal_node();
238 if (n->is_Allocate()) {
239 n->as_Allocate()->_is_non_escaping = noescape;
240 }
241 if (n->is_CallStaticJava()) {
242 n->as_CallStaticJava()->_is_non_escaping = noescape;
243 }
244 if (noescape && ptn->scalar_replaceable()) {
245 adjust_scalar_replaceable_state(ptn);
246 if (ptn->scalar_replaceable()) {
247 alloc_worklist.append(ptn->ideal_node());
248 }
249 }
250 }
251
252 #ifdef ASSERT
253 if (VerifyConnectionGraph) {
254 // Verify that graph is complete - no new edges could be added or needed.
255 verify_connection_graph(ptnodes_worklist, non_escaped_worklist,
256 java_objects_worklist, addp_worklist);
257 }
258 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build");
259 assert(null_obj->escape_state() == PointsToNode::NoEscape &&
260 null_obj->edge_count() == 0 &&
261 !null_obj->arraycopy_src() &&
262 !null_obj->arraycopy_dst(), "sanity");
263 #endif
264
265 _collecting = false;
266
267 } // TracePhase t3("connectionGraph")
268
269 // 4. Optimize ideal graph based on EA information.
270 bool has_non_escaping_obj = (non_escaped_worklist.length() > 0);
271 if (has_non_escaping_obj) {
272 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist);
273 }
274
275 #ifndef PRODUCT
276 if (PrintEscapeAnalysis) {
277 dump(ptnodes_worklist); // Dump ConnectionGraph
278 }
279 #endif
280
281 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0);
282 #ifdef ASSERT
283 if (VerifyConnectionGraph) {
284 int alloc_length = alloc_worklist.length();
285 for (int next = 0; next < alloc_length; ++next) {
286 Node* n = alloc_worklist.at(next);
287 PointsToNode* ptn = ptnode_adr(n->_idx);
288 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity");
289 }
290 }
291 #endif
292
293 // 5. Separate memory graph for scalar replaceable allcations.
294 if (has_scalar_replaceable_candidates &&
295 C->AliasLevel() >= 3 && EliminateAllocations) {
296 // Now use the escape information to create unique types for
297 // scalar replaceable objects.
298 split_unique_types(alloc_worklist, arraycopy_worklist);
299 if (C->failing()) return false;
300 C->print_method(PHASE_AFTER_EA, 2);
301
302 #ifdef ASSERT
303 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
304 tty->print("=== No allocations eliminated for ");
305 C->method()->print_short_name();
306 if(!EliminateAllocations) {
307 tty->print(" since EliminateAllocations is off ===");
308 } else if(!has_scalar_replaceable_candidates) {
309 tty->print(" since there are no scalar replaceable candidates ===");
310 } else if(C->AliasLevel() < 3) {
311 tty->print(" since AliasLevel < 3 ===");
312 }
313 tty->cr();
314 #endif
315 }
316 return has_non_escaping_obj;
317 }
318
319 // Utility function for nodes that load an object
320 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
321 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
322 // ThreadLocal has RawPtr type.
323 const Type* t = _igvn->type(n);
324 if (t->make_ptr() != NULL) {
325 Node* adr = n->in(MemNode::Address);
326 #ifdef ASSERT
327 if (!adr->is_AddP()) {
328 assert(_igvn->type(adr)->isa_rawptr(), "sanity");
329 } else {
330 assert((ptnode_adr(adr->_idx) == NULL ||
331 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity");
332 }
333 #endif
334 add_local_var_and_edge(n, PointsToNode::NoEscape,
335 adr, delayed_worklist);
336 }
337 }
338
339 // Populate Connection Graph with PointsTo nodes and create simple
340 // connection graph edges.
341 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
342 assert(!_verify, "this method should not be called for verification");
343 PhaseGVN* igvn = _igvn;
344 uint n_idx = n->_idx;
345 PointsToNode* n_ptn = ptnode_adr(n_idx);
346 if (n_ptn != NULL)
347 return; // No need to redefine PointsTo node during first iteration.
348
349 if (n->is_Call()) {
350 // Arguments to allocation and locking don't escape.
351 if (n->is_AbstractLock()) {
352 // Put Lock and Unlock nodes on IGVN worklist to process them during
353 // first IGVN optimization when escape information is still available.
354 record_for_optimizer(n);
355 } else if (n->is_Allocate()) {
356 add_call_node(n->as_Call());
357 record_for_optimizer(n);
358 } else {
359 if (n->is_CallStaticJava()) {
360 const char* name = n->as_CallStaticJava()->_name;
361 if (name != NULL && strcmp(name, "uncommon_trap") == 0)
362 return; // Skip uncommon traps
363 }
364 // Don't mark as processed since call's arguments have to be processed.
365 delayed_worklist->push(n);
366 // Check if a call returns an object.
367 if ((n->as_Call()->returns_pointer() &&
368 n->as_Call()->proj_out(TypeFunc::Parms) != NULL) ||
369 (n->is_CallStaticJava() &&
370 n->as_CallStaticJava()->is_boxing_method())) {
371 add_call_node(n->as_Call());
372 }
373 }
374 return;
375 }
376 // Put this check here to process call arguments since some call nodes
377 // point to phantom_obj.
378 if (n_ptn == phantom_obj || n_ptn == null_obj)
379 return; // Skip predefined nodes.
380
381 int opcode = n->Opcode();
382 switch (opcode) {
383 case Op_AddP: {
384 Node* base = get_addp_base(n);
385 PointsToNode* ptn_base = ptnode_adr(base->_idx);
386 // Field nodes are created for all field types. They are used in
387 // adjust_scalar_replaceable_state() and split_unique_types().
388 // Note, non-oop fields will have only base edges in Connection
389 // Graph because such fields are not used for oop loads and stores.
390 int offset = address_offset(n, igvn);
391 add_field(n, PointsToNode::NoEscape, offset);
392 if (ptn_base == NULL) {
393 delayed_worklist->push(n); // Process it later.
394 } else {
395 n_ptn = ptnode_adr(n_idx);
396 add_base(n_ptn->as_Field(), ptn_base);
397 }
398 break;
399 }
400 case Op_CastX2P: {
401 map_ideal_node(n, phantom_obj);
402 break;
403 }
404 case Op_CastPP:
405 case Op_CheckCastPP:
406 case Op_EncodeP:
407 case Op_DecodeN:
408 case Op_EncodePKlass:
409 case Op_DecodeNKlass: {
410 add_local_var_and_edge(n, PointsToNode::NoEscape,
411 n->in(1), delayed_worklist);
412 break;
413 }
414 case Op_CMoveP: {
415 add_local_var(n, PointsToNode::NoEscape);
416 // Do not add edges during first iteration because some could be
417 // not defined yet.
418 delayed_worklist->push(n);
419 break;
420 }
421 case Op_ConP:
422 case Op_ConN:
423 case Op_ConNKlass: {
424 // assume all oop constants globally escape except for null
425 PointsToNode::EscapeState es;
426 const Type* t = igvn->type(n);
427 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) {
428 es = PointsToNode::NoEscape;
429 } else {
430 es = PointsToNode::GlobalEscape;
431 }
432 add_java_object(n, es);
433 break;
434 }
435 case Op_CreateEx: {
436 // assume that all exception objects globally escape
437 map_ideal_node(n, phantom_obj);
438 break;
439 }
440 case Op_LoadKlass:
441 case Op_LoadNKlass: {
442 // Unknown class is loaded
443 map_ideal_node(n, phantom_obj);
444 break;
445 }
446 case Op_LoadP:
447 case Op_LoadN:
448 case Op_LoadPLocked: {
449 add_objload_to_connection_graph(n, delayed_worklist);
450 break;
451 }
452 case Op_Parm: {
453 map_ideal_node(n, phantom_obj);
454 break;
455 }
456 case Op_PartialSubtypeCheck: {
457 // Produces Null or notNull and is used in only in CmpP so
458 // phantom_obj could be used.
459 map_ideal_node(n, phantom_obj); // Result is unknown
460 break;
461 }
462 case Op_Phi: {
463 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
464 // ThreadLocal has RawPtr type.
465 const Type* t = n->as_Phi()->type();
466 if (t->make_ptr() != NULL) {
467 add_local_var(n, PointsToNode::NoEscape);
468 // Do not add edges during first iteration because some could be
469 // not defined yet.
470 delayed_worklist->push(n);
471 }
472 break;
473 }
474 case Op_Proj: {
475 // we are only interested in the oop result projection from a call
476 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
477 n->in(0)->as_Call()->returns_pointer()) {
478 add_local_var_and_edge(n, PointsToNode::NoEscape,
479 n->in(0), delayed_worklist);
480 }
481 break;
482 }
483 case Op_Rethrow: // Exception object escapes
484 case Op_Return: {
485 if (n->req() > TypeFunc::Parms &&
486 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
487 // Treat Return value as LocalVar with GlobalEscape escape state.
488 add_local_var_and_edge(n, PointsToNode::GlobalEscape,
489 n->in(TypeFunc::Parms), delayed_worklist);
490 }
491 break;
492 }
493 case Op_CompareAndExchangeP:
494 case Op_CompareAndExchangeN:
495 case Op_GetAndSetP:
496 case Op_GetAndSetN: {
497 add_objload_to_connection_graph(n, delayed_worklist);
498 // fallthrough
499 }
500 case Op_StoreP:
501 case Op_StoreN:
502 case Op_StoreNKlass:
503 case Op_StorePConditional:
504 case Op_WeakCompareAndSwapP:
505 case Op_WeakCompareAndSwapN:
506 case Op_CompareAndSwapP:
507 case Op_CompareAndSwapN: {
508 Node* adr = n->in(MemNode::Address);
509 const Type *adr_type = igvn->type(adr);
510 adr_type = adr_type->make_ptr();
511 if (adr_type == NULL) {
512 break; // skip dead nodes
513 }
514 if (adr_type->isa_oopptr() ||
515 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) &&
516 (adr_type == TypeRawPtr::NOTNULL &&
517 adr->in(AddPNode::Address)->is_Proj() &&
518 adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
519 delayed_worklist->push(n); // Process it later.
520 #ifdef ASSERT
521 assert(adr->is_AddP(), "expecting an AddP");
522 if (adr_type == TypeRawPtr::NOTNULL) {
523 // Verify a raw address for a store captured by Initialize node.
524 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
525 assert(offs != Type::OffsetBot, "offset must be a constant");
526 }
527 #endif
528 } else {
529 // Ignore copy the displaced header to the BoxNode (OSR compilation).
530 if (adr->is_BoxLock())
531 break;
532 // Stored value escapes in unsafe access.
533 if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
534 // Pointer stores in G1 barriers looks like unsafe access.
535 // Ignore such stores to be able scalar replace non-escaping
536 // allocations.
537 if (UseG1GC && adr->is_AddP()) {
538 Node* base = get_addp_base(adr);
539 if (base->Opcode() == Op_LoadP &&
540 base->in(MemNode::Address)->is_AddP()) {
541 adr = base->in(MemNode::Address);
542 Node* tls = get_addp_base(adr);
543 if (tls->Opcode() == Op_ThreadLocal) {
544 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
545 if (offs == in_bytes(JavaThread::satb_mark_queue_offset() +
546 SATBMarkQueue::byte_offset_of_buf())) {
547 break; // G1 pre barrier previous oop value store.
548 }
549 if (offs == in_bytes(JavaThread::dirty_card_queue_offset() +
550 DirtyCardQueue::byte_offset_of_buf())) {
551 break; // G1 post barrier card address store.
552 }
553 }
554 }
555 }
556 delayed_worklist->push(n); // Process unsafe access later.
557 break;
558 }
559 #ifdef ASSERT
560 n->dump(1);
561 assert(false, "not unsafe or G1 barrier raw StoreP");
562 #endif
563 }
564 break;
565 }
566 case Op_AryEq:
567 case Op_HasNegatives:
568 case Op_StrComp:
569 case Op_StrEquals:
570 case Op_StrIndexOf:
571 case Op_StrIndexOfChar:
572 case Op_StrInflatedCopy:
573 case Op_StrCompressedCopy:
574 case Op_EncodeISOArray: {
575 add_local_var(n, PointsToNode::ArgEscape);
576 delayed_worklist->push(n); // Process it later.
577 break;
578 }
579 case Op_ThreadLocal: {
580 add_java_object(n, PointsToNode::ArgEscape);
581 break;
582 }
583 default:
584 ; // Do nothing for nodes not related to EA.
585 }
586 return;
587 }
588
589 #ifdef ASSERT
590 #define ELSE_FAIL(name) \
591 /* Should not be called for not pointer type. */ \
592 n->dump(1); \
593 assert(false, name); \
594 break;
595 #else
596 #define ELSE_FAIL(name) \
597 break;
598 #endif
599
600 // Add final simple edges to graph.
601 void ConnectionGraph::add_final_edges(Node *n) {
602 PointsToNode* n_ptn = ptnode_adr(n->_idx);
603 #ifdef ASSERT
604 if (_verify && n_ptn->is_JavaObject())
605 return; // This method does not change graph for JavaObject.
606 #endif
607
608 if (n->is_Call()) {
609 process_call_arguments(n->as_Call());
610 return;
611 }
612 assert(n->is_Store() || n->is_LoadStore() ||
613 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL),
614 "node should be registered already");
615 int opcode = n->Opcode();
616 switch (opcode) {
617 case Op_AddP: {
618 Node* base = get_addp_base(n);
619 PointsToNode* ptn_base = ptnode_adr(base->_idx);
620 assert(ptn_base != NULL, "field's base should be registered");
621 add_base(n_ptn->as_Field(), ptn_base);
622 break;
623 }
624 case Op_CastPP:
625 case Op_CheckCastPP:
626 case Op_EncodeP:
627 case Op_DecodeN:
628 case Op_EncodePKlass:
629 case Op_DecodeNKlass: {
630 add_local_var_and_edge(n, PointsToNode::NoEscape,
631 n->in(1), NULL);
632 break;
633 }
634 case Op_CMoveP: {
635 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) {
636 Node* in = n->in(i);
637 if (in == NULL)
638 continue; // ignore NULL
639 Node* uncast_in = in->uncast();
640 if (uncast_in->is_top() || uncast_in == n)
641 continue; // ignore top or inputs which go back this node
642 PointsToNode* ptn = ptnode_adr(in->_idx);
643 assert(ptn != NULL, "node should be registered");
644 add_edge(n_ptn, ptn);
645 }
646 break;
647 }
648 case Op_LoadP:
649 case Op_LoadN:
650 case Op_LoadPLocked: {
651 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
652 // ThreadLocal has RawPtr type.
653 const Type* t = _igvn->type(n);
654 if (t->make_ptr() != NULL) {
655 Node* adr = n->in(MemNode::Address);
656 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
657 break;
658 }
659 ELSE_FAIL("Op_LoadP");
660 }
661 case Op_Phi: {
662 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
663 // ThreadLocal has RawPtr type.
664 const Type* t = n->as_Phi()->type();
665 if (t->make_ptr() != NULL) {
666 for (uint i = 1; i < n->req(); i++) {
667 Node* in = n->in(i);
668 if (in == NULL)
669 continue; // ignore NULL
670 Node* uncast_in = in->uncast();
671 if (uncast_in->is_top() || uncast_in == n)
672 continue; // ignore top or inputs which go back this node
673 PointsToNode* ptn = ptnode_adr(in->_idx);
674 assert(ptn != NULL, "node should be registered");
675 add_edge(n_ptn, ptn);
676 }
677 break;
678 }
679 ELSE_FAIL("Op_Phi");
680 }
681 case Op_Proj: {
682 // we are only interested in the oop result projection from a call
683 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
684 n->in(0)->as_Call()->returns_pointer()) {
685 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL);
686 break;
687 }
688 ELSE_FAIL("Op_Proj");
689 }
690 case Op_Rethrow: // Exception object escapes
691 case Op_Return: {
692 if (n->req() > TypeFunc::Parms &&
693 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
694 // Treat Return value as LocalVar with GlobalEscape escape state.
695 add_local_var_and_edge(n, PointsToNode::GlobalEscape,
696 n->in(TypeFunc::Parms), NULL);
697 break;
698 }
699 ELSE_FAIL("Op_Return");
700 }
701 case Op_StoreP:
702 case Op_StoreN:
703 case Op_StoreNKlass:
704 case Op_StorePConditional:
705 case Op_CompareAndExchangeP:
706 case Op_CompareAndExchangeN:
707 case Op_CompareAndSwapP:
708 case Op_CompareAndSwapN:
709 case Op_WeakCompareAndSwapP:
710 case Op_WeakCompareAndSwapN:
711 case Op_GetAndSetP:
712 case Op_GetAndSetN: {
713 Node* adr = n->in(MemNode::Address);
714 const Type *adr_type = _igvn->type(adr);
715 adr_type = adr_type->make_ptr();
716 #ifdef ASSERT
717 if (adr_type == NULL) {
718 n->dump(1);
719 assert(adr_type != NULL, "dead node should not be on list");
720 break;
721 }
722 #endif
723 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN) {
724 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
725 }
726 if (adr_type->isa_oopptr() ||
727 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) &&
728 (adr_type == TypeRawPtr::NOTNULL &&
729 adr->in(AddPNode::Address)->is_Proj() &&
730 adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
731 // Point Address to Value
732 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
733 assert(adr_ptn != NULL &&
734 adr_ptn->as_Field()->is_oop(), "node should be registered");
735 Node *val = n->in(MemNode::ValueIn);
736 PointsToNode* ptn = ptnode_adr(val->_idx);
737 assert(ptn != NULL, "node should be registered");
738 add_edge(adr_ptn, ptn);
739 break;
740 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
741 // Stored value escapes in unsafe access.
742 Node *val = n->in(MemNode::ValueIn);
743 PointsToNode* ptn = ptnode_adr(val->_idx);
744 assert(ptn != NULL, "node should be registered");
745 set_escape_state(ptn, PointsToNode::GlobalEscape);
746 // Add edge to object for unsafe access with offset.
747 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
748 assert(adr_ptn != NULL, "node should be registered");
749 if (adr_ptn->is_Field()) {
750 assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
751 add_edge(adr_ptn, ptn);
752 }
753 break;
754 }
755 ELSE_FAIL("Op_StoreP");
756 }
757 case Op_AryEq:
758 case Op_HasNegatives:
759 case Op_StrComp:
760 case Op_StrEquals:
761 case Op_StrIndexOf:
762 case Op_StrIndexOfChar:
763 case Op_StrInflatedCopy:
764 case Op_StrCompressedCopy:
765 case Op_EncodeISOArray: {
766 // char[]/byte[] arrays passed to string intrinsic do not escape but
767 // they are not scalar replaceable. Adjust escape state for them.
768 // Start from in(2) edge since in(1) is memory edge.
769 for (uint i = 2; i < n->req(); i++) {
770 Node* adr = n->in(i);
771 const Type* at = _igvn->type(adr);
772 if (!adr->is_top() && at->isa_ptr()) {
773 assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
774 at->isa_ptr() != NULL, "expecting a pointer");
775 if (adr->is_AddP()) {
776 adr = get_addp_base(adr);
777 }
778 PointsToNode* ptn = ptnode_adr(adr->_idx);
779 assert(ptn != NULL, "node should be registered");
780 add_edge(n_ptn, ptn);
781 }
782 }
783 break;
784 }
785 default: {
786 // This method should be called only for EA specific nodes which may
787 // miss some edges when they were created.
788 #ifdef ASSERT
789 n->dump(1);
790 #endif
791 guarantee(false, "unknown node");
792 }
793 }
794 return;
795 }
796
797 void ConnectionGraph::add_call_node(CallNode* call) {
798 assert(call->returns_pointer(), "only for call which returns pointer");
799 uint call_idx = call->_idx;
800 if (call->is_Allocate()) {
801 Node* k = call->in(AllocateNode::KlassNode);
802 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr();
803 assert(kt != NULL, "TypeKlassPtr required.");
804 ciKlass* cik = kt->klass();
805 PointsToNode::EscapeState es = PointsToNode::NoEscape;
806 bool scalar_replaceable = true;
807 if (call->is_AllocateArray()) {
808 if (!cik->is_array_klass()) { // StressReflectiveCode
809 es = PointsToNode::GlobalEscape;
810 } else {
811 int length = call->in(AllocateNode::ALength)->find_int_con(-1);
812 if (length < 0 || length > EliminateAllocationArraySizeLimit) {
813 // Not scalar replaceable if the length is not constant or too big.
814 scalar_replaceable = false;
815 }
816 }
817 } else { // Allocate instance
818 if (cik->is_subclass_of(_compile->env()->Thread_klass()) ||
819 cik->is_subclass_of(_compile->env()->Reference_klass()) ||
820 !cik->is_instance_klass() || // StressReflectiveCode
821 !cik->as_instance_klass()->can_be_instantiated() ||
822 cik->as_instance_klass()->has_finalizer()) {
823 es = PointsToNode::GlobalEscape;
824 }
825 }
826 add_java_object(call, es);
827 PointsToNode* ptn = ptnode_adr(call_idx);
828 if (!scalar_replaceable && ptn->scalar_replaceable()) {
829 ptn->set_scalar_replaceable(false);
830 }
831 } else if (call->is_CallStaticJava()) {
832 // Call nodes could be different types:
833 //
834 // 1. CallDynamicJavaNode (what happened during call is unknown):
835 //
836 // - mapped to GlobalEscape JavaObject node if oop is returned;
837 //
838 // - all oop arguments are escaping globally;
839 //
840 // 2. CallStaticJavaNode (execute bytecode analysis if possible):
841 //
842 // - the same as CallDynamicJavaNode if can't do bytecode analysis;
843 //
844 // - mapped to GlobalEscape JavaObject node if unknown oop is returned;
845 // - mapped to NoEscape JavaObject node if non-escaping object allocated
846 // during call is returned;
847 // - mapped to ArgEscape LocalVar node pointed to object arguments
848 // which are returned and does not escape during call;
849 //
850 // - oop arguments escaping status is defined by bytecode analysis;
851 //
852 // For a static call, we know exactly what method is being called.
853 // Use bytecode estimator to record whether the call's return value escapes.
854 ciMethod* meth = call->as_CallJava()->method();
855 if (meth == NULL) {
856 const char* name = call->as_CallStaticJava()->_name;
857 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check");
858 // Returns a newly allocated unescaped object.
859 add_java_object(call, PointsToNode::NoEscape);
860 ptnode_adr(call_idx)->set_scalar_replaceable(false);
861 } else if (meth->is_boxing_method()) {
862 // Returns boxing object
863 PointsToNode::EscapeState es;
864 vmIntrinsics::ID intr = meth->intrinsic_id();
865 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) {
866 // It does not escape if object is always allocated.
867 es = PointsToNode::NoEscape;
868 } else {
869 // It escapes globally if object could be loaded from cache.
870 es = PointsToNode::GlobalEscape;
871 }
872 add_java_object(call, es);
873 } else {
874 BCEscapeAnalyzer* call_analyzer = meth->get_bcea();
875 call_analyzer->copy_dependencies(_compile->dependencies());
876 if (call_analyzer->is_return_allocated()) {
877 // Returns a newly allocated unescaped object, simply
878 // update dependency information.
879 // Mark it as NoEscape so that objects referenced by
880 // it's fields will be marked as NoEscape at least.
881 add_java_object(call, PointsToNode::NoEscape);
882 ptnode_adr(call_idx)->set_scalar_replaceable(false);
883 } else {
884 // Determine whether any arguments are returned.
885 const TypeTuple* d = call->tf()->domain();
886 bool ret_arg = false;
887 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
888 if (d->field_at(i)->isa_ptr() != NULL &&
889 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
890 ret_arg = true;
891 break;
892 }
893 }
894 if (ret_arg) {
895 add_local_var(call, PointsToNode::ArgEscape);
896 } else {
897 // Returns unknown object.
898 map_ideal_node(call, phantom_obj);
899 }
900 }
901 }
902 } else {
903 // An other type of call, assume the worst case:
904 // returned value is unknown and globally escapes.
905 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check");
906 map_ideal_node(call, phantom_obj);
907 }
908 }
909
910 void ConnectionGraph::process_call_arguments(CallNode *call) {
911 bool is_arraycopy = false;
912 switch (call->Opcode()) {
913 #ifdef ASSERT
914 case Op_Allocate:
915 case Op_AllocateArray:
916 case Op_Lock:
917 case Op_Unlock:
918 assert(false, "should be done already");
919 break;
920 #endif
921 case Op_ArrayCopy:
922 case Op_CallLeafNoFP:
923 // Most array copies are ArrayCopy nodes at this point but there
924 // are still a few direct calls to the copy subroutines (See
925 // PhaseStringOpts::copy_string())
926 is_arraycopy = (call->Opcode() == Op_ArrayCopy) ||
927 call->as_CallLeaf()->is_call_to_arraycopystub();
928 // fall through
929 case Op_CallLeaf: {
930 // Stub calls, objects do not escape but they are not scale replaceable.
931 // Adjust escape state for outgoing arguments.
932 const TypeTuple * d = call->tf()->domain();
933 bool src_has_oops = false;
934 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
935 const Type* at = d->field_at(i);
936 Node *arg = call->in(i);
937 if (arg == NULL) {
938 continue;
939 }
940 const Type *aat = _igvn->type(arg);
941 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr())
942 continue;
943 if (arg->is_AddP()) {
944 //
945 // The inline_native_clone() case when the arraycopy stub is called
946 // after the allocation before Initialize and CheckCastPP nodes.
947 // Or normal arraycopy for object arrays case.
948 //
949 // Set AddP's base (Allocate) as not scalar replaceable since
950 // pointer to the base (with offset) is passed as argument.
951 //
952 arg = get_addp_base(arg);
953 }
954 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
955 assert(arg_ptn != NULL, "should be registered");
956 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state();
957 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) {
958 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
959 aat->isa_ptr() != NULL, "expecting an Ptr");
960 bool arg_has_oops = aat->isa_oopptr() &&
961 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() ||
962 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass()));
963 if (i == TypeFunc::Parms) {
964 src_has_oops = arg_has_oops;
965 }
966 //
967 // src or dst could be j.l.Object when other is basic type array:
968 //
969 // arraycopy(char[],0,Object*,0,size);
970 // arraycopy(Object*,0,char[],0,size);
971 //
972 // Don't add edges in such cases.
973 //
974 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy &&
975 arg_has_oops && (i > TypeFunc::Parms);
976 #ifdef ASSERT
977 if (!(is_arraycopy ||
978 (call->as_CallLeaf()->_name != NULL &&
979 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 ||
980 strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 ||
981 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 ||
982 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 ||
983 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 ||
984 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 ||
985 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 ||
986 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 ||
987 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 ||
988 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 ||
989 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 ||
990 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 ||
991 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 ||
992 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 ||
993 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 ||
994 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 ||
995 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 ||
996 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 ||
997 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 ||
998 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 ||
999 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 ||
1000 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 ||
1001 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0)
1002 ))) {
1003 call->dump();
1004 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name);
1005 }
1006 #endif
1007 // Always process arraycopy's destination object since
1008 // we need to add all possible edges to references in
1009 // source object.
1010 if (arg_esc >= PointsToNode::ArgEscape &&
1011 !arg_is_arraycopy_dest) {
1012 continue;
1013 }
1014 PointsToNode::EscapeState es = PointsToNode::ArgEscape;
1015 if (call->is_ArrayCopy()) {
1016 ArrayCopyNode* ac = call->as_ArrayCopy();
1017 if (ac->is_clonebasic() ||
1018 ac->is_arraycopy_validated() ||
1019 ac->is_copyof_validated() ||
1020 ac->is_copyofrange_validated()) {
1021 es = PointsToNode::NoEscape;
1022 }
1023 }
1024 set_escape_state(arg_ptn, es);
1025 if (arg_is_arraycopy_dest) {
1026 Node* src = call->in(TypeFunc::Parms);
1027 if (src->is_AddP()) {
1028 src = get_addp_base(src);
1029 }
1030 PointsToNode* src_ptn = ptnode_adr(src->_idx);
1031 assert(src_ptn != NULL, "should be registered");
1032 if (arg_ptn != src_ptn) {
1033 // Special arraycopy edge:
1034 // A destination object's field can't have the source object
1035 // as base since objects escape states are not related.
1036 // Only escape state of destination object's fields affects
1037 // escape state of fields in source object.
1038 add_arraycopy(call, es, src_ptn, arg_ptn);
1039 }
1040 }
1041 }
1042 }
1043 break;
1044 }
1045 case Op_CallStaticJava: {
1046 // For a static call, we know exactly what method is being called.
1047 // Use bytecode estimator to record the call's escape affects
1048 #ifdef ASSERT
1049 const char* name = call->as_CallStaticJava()->_name;
1050 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only");
1051 #endif
1052 ciMethod* meth = call->as_CallJava()->method();
1053 if ((meth != NULL) && meth->is_boxing_method()) {
1054 break; // Boxing methods do not modify any oops.
1055 }
1056 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
1057 // fall-through if not a Java method or no analyzer information
1058 if (call_analyzer != NULL) {
1059 PointsToNode* call_ptn = ptnode_adr(call->_idx);
1060 const TypeTuple* d = call->tf()->domain();
1061 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1062 const Type* at = d->field_at(i);
1063 int k = i - TypeFunc::Parms;
1064 Node* arg = call->in(i);
1065 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1066 if (at->isa_ptr() != NULL &&
1067 call_analyzer->is_arg_returned(k)) {
1068 // The call returns arguments.
1069 if (call_ptn != NULL) { // Is call's result used?
1070 assert(call_ptn->is_LocalVar(), "node should be registered");
1071 assert(arg_ptn != NULL, "node should be registered");
1072 add_edge(call_ptn, arg_ptn);
1073 }
1074 }
1075 if (at->isa_oopptr() != NULL &&
1076 arg_ptn->escape_state() < PointsToNode::GlobalEscape) {
1077 if (!call_analyzer->is_arg_stack(k)) {
1078 // The argument global escapes
1079 set_escape_state(arg_ptn, PointsToNode::GlobalEscape);
1080 } else {
1081 set_escape_state(arg_ptn, PointsToNode::ArgEscape);
1082 if (!call_analyzer->is_arg_local(k)) {
1083 // The argument itself doesn't escape, but any fields might
1084 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape);
1085 }
1086 }
1087 }
1088 }
1089 if (call_ptn != NULL && call_ptn->is_LocalVar()) {
1090 // The call returns arguments.
1091 assert(call_ptn->edge_count() > 0, "sanity");
1092 if (!call_analyzer->is_return_local()) {
1093 // Returns also unknown object.
1094 add_edge(call_ptn, phantom_obj);
1095 }
1096 }
1097 break;
1098 }
1099 }
1100 default: {
1101 // Fall-through here if not a Java method or no analyzer information
1102 // or some other type of call, assume the worst case: all arguments
1103 // globally escape.
1104 const TypeTuple* d = call->tf()->domain();
1105 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1106 const Type* at = d->field_at(i);
1107 if (at->isa_oopptr() != NULL) {
1108 Node* arg = call->in(i);
1109 if (arg->is_AddP()) {
1110 arg = get_addp_base(arg);
1111 }
1112 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already");
1113 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape);
1114 }
1115 }
1116 }
1117 }
1118 }
1119
1120
1121 // Finish Graph construction.
1122 bool ConnectionGraph::complete_connection_graph(
1123 GrowableArray<PointsToNode*>& ptnodes_worklist,
1124 GrowableArray<JavaObjectNode*>& non_escaped_worklist,
1125 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1126 GrowableArray<FieldNode*>& oop_fields_worklist) {
1127 // Normally only 1-3 passes needed to build Connection Graph depending
1128 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler.
1129 // Set limit to 20 to catch situation when something did go wrong and
1130 // bailout Escape Analysis.
1131 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag.
1132 #define CG_BUILD_ITER_LIMIT 20
1133
1134 // Propagate GlobalEscape and ArgEscape escape states and check that
1135 // we still have non-escaping objects. The method pushs on _worklist
1136 // Field nodes which reference phantom_object.
1137 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) {
1138 return false; // Nothing to do.
1139 }
1140 // Now propagate references to all JavaObject nodes.
1141 int java_objects_length = java_objects_worklist.length();
1142 elapsedTimer time;
1143 bool timeout = false;
1144 int new_edges = 1;
1145 int iterations = 0;
1146 do {
1147 while ((new_edges > 0) &&
1148 (iterations++ < CG_BUILD_ITER_LIMIT)) {
1149 double start_time = time.seconds();
1150 time.start();
1151 new_edges = 0;
1152 // Propagate references to phantom_object for nodes pushed on _worklist
1153 // by find_non_escaped_objects() and find_field_value().
1154 new_edges += add_java_object_edges(phantom_obj, false);
1155 for (int next = 0; next < java_objects_length; ++next) {
1156 JavaObjectNode* ptn = java_objects_worklist.at(next);
1157 new_edges += add_java_object_edges(ptn, true);
1158
1159 #define SAMPLE_SIZE 4
1160 if ((next % SAMPLE_SIZE) == 0) {
1161 // Each 4 iterations calculate how much time it will take
1162 // to complete graph construction.
1163 time.stop();
1164 // Poll for requests from shutdown mechanism to quiesce compiler
1165 // because Connection graph construction may take long time.
1166 CompileBroker::maybe_block();
1167 double stop_time = time.seconds();
1168 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE;
1169 double time_until_end = time_per_iter * (double)(java_objects_length - next);
1170 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) {
1171 timeout = true;
1172 break; // Timeout
1173 }
1174 start_time = stop_time;
1175 time.start();
1176 }
1177 #undef SAMPLE_SIZE
1178
1179 }
1180 if (timeout) break;
1181 if (new_edges > 0) {
1182 // Update escape states on each iteration if graph was updated.
1183 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) {
1184 return false; // Nothing to do.
1185 }
1186 }
1187 time.stop();
1188 if (time.seconds() >= EscapeAnalysisTimeout) {
1189 timeout = true;
1190 break;
1191 }
1192 }
1193 if ((iterations < CG_BUILD_ITER_LIMIT) && !timeout) {
1194 time.start();
1195 // Find fields which have unknown value.
1196 int fields_length = oop_fields_worklist.length();
1197 for (int next = 0; next < fields_length; next++) {
1198 FieldNode* field = oop_fields_worklist.at(next);
1199 if (field->edge_count() == 0) {
1200 new_edges += find_field_value(field);
1201 // This code may added new edges to phantom_object.
1202 // Need an other cycle to propagate references to phantom_object.
1203 }
1204 }
1205 time.stop();
1206 if (time.seconds() >= EscapeAnalysisTimeout) {
1207 timeout = true;
1208 break;
1209 }
1210 } else {
1211 new_edges = 0; // Bailout
1212 }
1213 } while (new_edges > 0);
1214
1215 // Bailout if passed limits.
1216 if ((iterations >= CG_BUILD_ITER_LIMIT) || timeout) {
1217 Compile* C = _compile;
1218 if (C->log() != NULL) {
1219 C->log()->begin_elem("connectionGraph_bailout reason='reached ");
1220 C->log()->text("%s", timeout ? "time" : "iterations");
1221 C->log()->end_elem(" limit'");
1222 }
1223 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d",
1224 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length());
1225 // Possible infinite build_connection_graph loop,
1226 // bailout (no changes to ideal graph were made).
1227 return false;
1228 }
1229 #ifdef ASSERT
1230 if (Verbose && PrintEscapeAnalysis) {
1231 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d",
1232 iterations, nodes_size(), ptnodes_worklist.length());
1233 }
1234 #endif
1235
1236 #undef CG_BUILD_ITER_LIMIT
1237
1238 // Find fields initialized by NULL for non-escaping Allocations.
1239 int non_escaped_length = non_escaped_worklist.length();
1240 for (int next = 0; next < non_escaped_length; next++) {
1241 JavaObjectNode* ptn = non_escaped_worklist.at(next);
1242 PointsToNode::EscapeState es = ptn->escape_state();
1243 assert(es <= PointsToNode::ArgEscape, "sanity");
1244 if (es == PointsToNode::NoEscape) {
1245 if (find_init_values(ptn, null_obj, _igvn) > 0) {
1246 // Adding references to NULL object does not change escape states
1247 // since it does not escape. Also no fields are added to NULL object.
1248 add_java_object_edges(null_obj, false);
1249 }
1250 }
1251 Node* n = ptn->ideal_node();
1252 if (n->is_Allocate()) {
1253 // The object allocated by this Allocate node will never be
1254 // seen by an other thread. Mark it so that when it is
1255 // expanded no MemBarStoreStore is added.
1256 InitializeNode* ini = n->as_Allocate()->initialization();
1257 if (ini != NULL)
1258 ini->set_does_not_escape();
1259 }
1260 }
1261 return true; // Finished graph construction.
1262 }
1263
1264 // Propagate GlobalEscape and ArgEscape escape states to all nodes
1265 // and check that we still have non-escaping java objects.
1266 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist,
1267 GrowableArray<JavaObjectNode*>& non_escaped_worklist) {
1268 GrowableArray<PointsToNode*> escape_worklist;
1269 // First, put all nodes with GlobalEscape and ArgEscape states on worklist.
1270 int ptnodes_length = ptnodes_worklist.length();
1271 for (int next = 0; next < ptnodes_length; ++next) {
1272 PointsToNode* ptn = ptnodes_worklist.at(next);
1273 if (ptn->escape_state() >= PointsToNode::ArgEscape ||
1274 ptn->fields_escape_state() >= PointsToNode::ArgEscape) {
1275 escape_worklist.push(ptn);
1276 }
1277 }
1278 // Set escape states to referenced nodes (edges list).
1279 while (escape_worklist.length() > 0) {
1280 PointsToNode* ptn = escape_worklist.pop();
1281 PointsToNode::EscapeState es = ptn->escape_state();
1282 PointsToNode::EscapeState field_es = ptn->fields_escape_state();
1283 if (ptn->is_Field() && ptn->as_Field()->is_oop() &&
1284 es >= PointsToNode::ArgEscape) {
1285 // GlobalEscape or ArgEscape state of field means it has unknown value.
1286 if (add_edge(ptn, phantom_obj)) {
1287 // New edge was added
1288 add_field_uses_to_worklist(ptn->as_Field());
1289 }
1290 }
1291 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1292 PointsToNode* e = i.get();
1293 if (e->is_Arraycopy()) {
1294 assert(ptn->arraycopy_dst(), "sanity");
1295 // Propagate only fields escape state through arraycopy edge.
1296 if (e->fields_escape_state() < field_es) {
1297 set_fields_escape_state(e, field_es);
1298 escape_worklist.push(e);
1299 }
1300 } else if (es >= field_es) {
1301 // fields_escape_state is also set to 'es' if it is less than 'es'.
1302 if (e->escape_state() < es) {
1303 set_escape_state(e, es);
1304 escape_worklist.push(e);
1305 }
1306 } else {
1307 // Propagate field escape state.
1308 bool es_changed = false;
1309 if (e->fields_escape_state() < field_es) {
1310 set_fields_escape_state(e, field_es);
1311 es_changed = true;
1312 }
1313 if ((e->escape_state() < field_es) &&
1314 e->is_Field() && ptn->is_JavaObject() &&
1315 e->as_Field()->is_oop()) {
1316 // Change escape state of referenced fields.
1317 set_escape_state(e, field_es);
1318 es_changed = true;
1319 } else if (e->escape_state() < es) {
1320 set_escape_state(e, es);
1321 es_changed = true;
1322 }
1323 if (es_changed) {
1324 escape_worklist.push(e);
1325 }
1326 }
1327 }
1328 }
1329 // Remove escaped objects from non_escaped list.
1330 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) {
1331 JavaObjectNode* ptn = non_escaped_worklist.at(next);
1332 if (ptn->escape_state() >= PointsToNode::GlobalEscape) {
1333 non_escaped_worklist.delete_at(next);
1334 }
1335 if (ptn->escape_state() == PointsToNode::NoEscape) {
1336 // Find fields in non-escaped allocations which have unknown value.
1337 find_init_values(ptn, phantom_obj, NULL);
1338 }
1339 }
1340 return (non_escaped_worklist.length() > 0);
1341 }
1342
1343 // Add all references to JavaObject node by walking over all uses.
1344 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) {
1345 int new_edges = 0;
1346 if (populate_worklist) {
1347 // Populate _worklist by uses of jobj's uses.
1348 for (UseIterator i(jobj); i.has_next(); i.next()) {
1349 PointsToNode* use = i.get();
1350 if (use->is_Arraycopy())
1351 continue;
1352 add_uses_to_worklist(use);
1353 if (use->is_Field() && use->as_Field()->is_oop()) {
1354 // Put on worklist all field's uses (loads) and
1355 // related field nodes (same base and offset).
1356 add_field_uses_to_worklist(use->as_Field());
1357 }
1358 }
1359 }
1360 for (int l = 0; l < _worklist.length(); l++) {
1361 PointsToNode* use = _worklist.at(l);
1362 if (PointsToNode::is_base_use(use)) {
1363 // Add reference from jobj to field and from field to jobj (field's base).
1364 use = PointsToNode::get_use_node(use)->as_Field();
1365 if (add_base(use->as_Field(), jobj)) {
1366 new_edges++;
1367 }
1368 continue;
1369 }
1370 assert(!use->is_JavaObject(), "sanity");
1371 if (use->is_Arraycopy()) {
1372 if (jobj == null_obj) // NULL object does not have field edges
1373 continue;
1374 // Added edge from Arraycopy node to arraycopy's source java object
1375 if (add_edge(use, jobj)) {
1376 jobj->set_arraycopy_src();
1377 new_edges++;
1378 }
1379 // and stop here.
1380 continue;
1381 }
1382 if (!add_edge(use, jobj))
1383 continue; // No new edge added, there was such edge already.
1384 new_edges++;
1385 if (use->is_LocalVar()) {
1386 add_uses_to_worklist(use);
1387 if (use->arraycopy_dst()) {
1388 for (EdgeIterator i(use); i.has_next(); i.next()) {
1389 PointsToNode* e = i.get();
1390 if (e->is_Arraycopy()) {
1391 if (jobj == null_obj) // NULL object does not have field edges
1392 continue;
1393 // Add edge from arraycopy's destination java object to Arraycopy node.
1394 if (add_edge(jobj, e)) {
1395 new_edges++;
1396 jobj->set_arraycopy_dst();
1397 }
1398 }
1399 }
1400 }
1401 } else {
1402 // Added new edge to stored in field values.
1403 // Put on worklist all field's uses (loads) and
1404 // related field nodes (same base and offset).
1405 add_field_uses_to_worklist(use->as_Field());
1406 }
1407 }
1408 _worklist.clear();
1409 _in_worklist.Reset();
1410 return new_edges;
1411 }
1412
1413 // Put on worklist all related field nodes.
1414 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) {
1415 assert(field->is_oop(), "sanity");
1416 int offset = field->offset();
1417 add_uses_to_worklist(field);
1418 // Loop over all bases of this field and push on worklist Field nodes
1419 // with the same offset and base (since they may reference the same field).
1420 for (BaseIterator i(field); i.has_next(); i.next()) {
1421 PointsToNode* base = i.get();
1422 add_fields_to_worklist(field, base);
1423 // Check if the base was source object of arraycopy and go over arraycopy's
1424 // destination objects since values stored to a field of source object are
1425 // accessable by uses (loads) of fields of destination objects.
1426 if (base->arraycopy_src()) {
1427 for (UseIterator j(base); j.has_next(); j.next()) {
1428 PointsToNode* arycp = j.get();
1429 if (arycp->is_Arraycopy()) {
1430 for (UseIterator k(arycp); k.has_next(); k.next()) {
1431 PointsToNode* abase = k.get();
1432 if (abase->arraycopy_dst() && abase != base) {
1433 // Look for the same arraycopy reference.
1434 add_fields_to_worklist(field, abase);
1435 }
1436 }
1437 }
1438 }
1439 }
1440 }
1441 }
1442
1443 // Put on worklist all related field nodes.
1444 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) {
1445 int offset = field->offset();
1446 if (base->is_LocalVar()) {
1447 for (UseIterator j(base); j.has_next(); j.next()) {
1448 PointsToNode* f = j.get();
1449 if (PointsToNode::is_base_use(f)) { // Field
1450 f = PointsToNode::get_use_node(f);
1451 if (f == field || !f->as_Field()->is_oop())
1452 continue;
1453 int offs = f->as_Field()->offset();
1454 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1455 add_to_worklist(f);
1456 }
1457 }
1458 }
1459 } else {
1460 assert(base->is_JavaObject(), "sanity");
1461 if (// Skip phantom_object since it is only used to indicate that
1462 // this field's content globally escapes.
1463 (base != phantom_obj) &&
1464 // NULL object node does not have fields.
1465 (base != null_obj)) {
1466 for (EdgeIterator i(base); i.has_next(); i.next()) {
1467 PointsToNode* f = i.get();
1468 // Skip arraycopy edge since store to destination object field
1469 // does not update value in source object field.
1470 if (f->is_Arraycopy()) {
1471 assert(base->arraycopy_dst(), "sanity");
1472 continue;
1473 }
1474 if (f == field || !f->as_Field()->is_oop())
1475 continue;
1476 int offs = f->as_Field()->offset();
1477 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1478 add_to_worklist(f);
1479 }
1480 }
1481 }
1482 }
1483 }
1484
1485 // Find fields which have unknown value.
1486 int ConnectionGraph::find_field_value(FieldNode* field) {
1487 // Escaped fields should have init value already.
1488 assert(field->escape_state() == PointsToNode::NoEscape, "sanity");
1489 int new_edges = 0;
1490 for (BaseIterator i(field); i.has_next(); i.next()) {
1491 PointsToNode* base = i.get();
1492 if (base->is_JavaObject()) {
1493 // Skip Allocate's fields which will be processed later.
1494 if (base->ideal_node()->is_Allocate())
1495 return 0;
1496 assert(base == null_obj, "only NULL ptr base expected here");
1497 }
1498 }
1499 if (add_edge(field, phantom_obj)) {
1500 // New edge was added
1501 new_edges++;
1502 add_field_uses_to_worklist(field);
1503 }
1504 return new_edges;
1505 }
1506
1507 // Find fields initializing values for allocations.
1508 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) {
1509 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
1510 int new_edges = 0;
1511 Node* alloc = pta->ideal_node();
1512 if (init_val == phantom_obj) {
1513 // Do nothing for Allocate nodes since its fields values are
1514 // "known" unless they are initialized by arraycopy/clone.
1515 if (alloc->is_Allocate() && !pta->arraycopy_dst())
1516 return 0;
1517 assert(pta->arraycopy_dst() || alloc->as_CallStaticJava(), "sanity");
1518 #ifdef ASSERT
1519 if (!pta->arraycopy_dst() && alloc->as_CallStaticJava()->method() == NULL) {
1520 const char* name = alloc->as_CallStaticJava()->_name;
1521 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity");
1522 }
1523 #endif
1524 // Non-escaped allocation returned from Java or runtime call have
1525 // unknown values in fields.
1526 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1527 PointsToNode* field = i.get();
1528 if (field->is_Field() && field->as_Field()->is_oop()) {
1529 if (add_edge(field, phantom_obj)) {
1530 // New edge was added
1531 new_edges++;
1532 add_field_uses_to_worklist(field->as_Field());
1533 }
1534 }
1535 }
1536 return new_edges;
1537 }
1538 assert(init_val == null_obj, "sanity");
1539 // Do nothing for Call nodes since its fields values are unknown.
1540 if (!alloc->is_Allocate())
1541 return 0;
1542
1543 InitializeNode* ini = alloc->as_Allocate()->initialization();
1544 bool visited_bottom_offset = false;
1545 GrowableArray<int> offsets_worklist;
1546
1547 // Check if an oop field's initializing value is recorded and add
1548 // a corresponding NULL if field's value if it is not recorded.
1549 // Connection Graph does not record a default initialization by NULL
1550 // captured by Initialize node.
1551 //
1552 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1553 PointsToNode* field = i.get(); // Field (AddP)
1554 if (!field->is_Field() || !field->as_Field()->is_oop())
1555 continue; // Not oop field
1556 int offset = field->as_Field()->offset();
1557 if (offset == Type::OffsetBot) {
1558 if (!visited_bottom_offset) {
1559 // OffsetBot is used to reference array's element,
1560 // always add reference to NULL to all Field nodes since we don't
1561 // known which element is referenced.
1562 if (add_edge(field, null_obj)) {
1563 // New edge was added
1564 new_edges++;
1565 add_field_uses_to_worklist(field->as_Field());
1566 visited_bottom_offset = true;
1567 }
1568 }
1569 } else {
1570 // Check only oop fields.
1571 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type();
1572 if (adr_type->isa_rawptr()) {
1573 #ifdef ASSERT
1574 // Raw pointers are used for initializing stores so skip it
1575 // since it should be recorded already
1576 Node* base = get_addp_base(field->ideal_node());
1577 assert(adr_type->isa_rawptr() && base->is_Proj() &&
1578 (base->in(0) == alloc),"unexpected pointer type");
1579 #endif
1580 continue;
1581 }
1582 if (!offsets_worklist.contains(offset)) {
1583 offsets_worklist.append(offset);
1584 Node* value = NULL;
1585 if (ini != NULL) {
1586 // StoreP::memory_type() == T_ADDRESS
1587 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS;
1588 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase);
1589 // Make sure initializing store has the same type as this AddP.
1590 // This AddP may reference non existing field because it is on a
1591 // dead branch of bimorphic call which is not eliminated yet.
1592 if (store != NULL && store->is_Store() &&
1593 store->as_Store()->memory_type() == ft) {
1594 value = store->in(MemNode::ValueIn);
1595 #ifdef ASSERT
1596 if (VerifyConnectionGraph) {
1597 // Verify that AddP already points to all objects the value points to.
1598 PointsToNode* val = ptnode_adr(value->_idx);
1599 assert((val != NULL), "should be processed already");
1600 PointsToNode* missed_obj = NULL;
1601 if (val->is_JavaObject()) {
1602 if (!field->points_to(val->as_JavaObject())) {
1603 missed_obj = val;
1604 }
1605 } else {
1606 if (!val->is_LocalVar() || (val->edge_count() == 0)) {
1607 tty->print_cr("----------init store has invalid value -----");
1608 store->dump();
1609 val->dump();
1610 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already");
1611 }
1612 for (EdgeIterator j(val); j.has_next(); j.next()) {
1613 PointsToNode* obj = j.get();
1614 if (obj->is_JavaObject()) {
1615 if (!field->points_to(obj->as_JavaObject())) {
1616 missed_obj = obj;
1617 break;
1618 }
1619 }
1620 }
1621 }
1622 if (missed_obj != NULL) {
1623 tty->print_cr("----------field---------------------------------");
1624 field->dump();
1625 tty->print_cr("----------missed referernce to object-----------");
1626 missed_obj->dump();
1627 tty->print_cr("----------object referernced by init store -----");
1628 store->dump();
1629 val->dump();
1630 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference");
1631 }
1632 }
1633 #endif
1634 } else {
1635 // There could be initializing stores which follow allocation.
1636 // For example, a volatile field store is not collected
1637 // by Initialize node.
1638 //
1639 // Need to check for dependent loads to separate such stores from
1640 // stores which follow loads. For now, add initial value NULL so
1641 // that compare pointers optimization works correctly.
1642 }
1643 }
1644 if (value == NULL) {
1645 // A field's initializing value was not recorded. Add NULL.
1646 if (add_edge(field, null_obj)) {
1647 // New edge was added
1648 new_edges++;
1649 add_field_uses_to_worklist(field->as_Field());
1650 }
1651 }
1652 }
1653 }
1654 }
1655 return new_edges;
1656 }
1657
1658 // Adjust scalar_replaceable state after Connection Graph is built.
1659 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) {
1660 // Search for non-escaping objects which are not scalar replaceable
1661 // and mark them to propagate the state to referenced objects.
1662
1663 // 1. An object is not scalar replaceable if the field into which it is
1664 // stored has unknown offset (stored into unknown element of an array).
1665 //
1666 for (UseIterator i(jobj); i.has_next(); i.next()) {
1667 PointsToNode* use = i.get();
1668 if (use->is_Arraycopy()) {
1669 continue;
1670 }
1671 if (use->is_Field()) {
1672 FieldNode* field = use->as_Field();
1673 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
1674 if (field->offset() == Type::OffsetBot) {
1675 jobj->set_scalar_replaceable(false);
1676 return;
1677 }
1678 // 2. An object is not scalar replaceable if the field into which it is
1679 // stored has multiple bases one of which is null.
1680 if (field->base_count() > 1) {
1681 for (BaseIterator i(field); i.has_next(); i.next()) {
1682 PointsToNode* base = i.get();
1683 if (base == null_obj) {
1684 jobj->set_scalar_replaceable(false);
1685 return;
1686 }
1687 }
1688 }
1689 }
1690 assert(use->is_Field() || use->is_LocalVar(), "sanity");
1691 // 3. An object is not scalar replaceable if it is merged with other objects.
1692 for (EdgeIterator j(use); j.has_next(); j.next()) {
1693 PointsToNode* ptn = j.get();
1694 if (ptn->is_JavaObject() && ptn != jobj) {
1695 // Mark all objects.
1696 jobj->set_scalar_replaceable(false);
1697 ptn->set_scalar_replaceable(false);
1698 }
1699 }
1700 if (!jobj->scalar_replaceable()) {
1701 return;
1702 }
1703 }
1704
1705 for (EdgeIterator j(jobj); j.has_next(); j.next()) {
1706 if (j.get()->is_Arraycopy()) {
1707 continue;
1708 }
1709
1710 // Non-escaping object node should point only to field nodes.
1711 FieldNode* field = j.get()->as_Field();
1712 int offset = field->as_Field()->offset();
1713
1714 // 4. An object is not scalar replaceable if it has a field with unknown
1715 // offset (array's element is accessed in loop).
1716 if (offset == Type::OffsetBot) {
1717 jobj->set_scalar_replaceable(false);
1718 return;
1719 }
1720 // 5. Currently an object is not scalar replaceable if a LoadStore node
1721 // access its field since the field value is unknown after it.
1722 //
1723 Node* n = field->ideal_node();
1724 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1725 if (n->fast_out(i)->is_LoadStore()) {
1726 jobj->set_scalar_replaceable(false);
1727 return;
1728 }
1729 }
1730
1731 // 6. Or the address may point to more then one object. This may produce
1732 // the false positive result (set not scalar replaceable)
1733 // since the flow-insensitive escape analysis can't separate
1734 // the case when stores overwrite the field's value from the case
1735 // when stores happened on different control branches.
1736 //
1737 // Note: it will disable scalar replacement in some cases:
1738 //
1739 // Point p[] = new Point[1];
1740 // p[0] = new Point(); // Will be not scalar replaced
1741 //
1742 // but it will save us from incorrect optimizations in next cases:
1743 //
1744 // Point p[] = new Point[1];
1745 // if ( x ) p[0] = new Point(); // Will be not scalar replaced
1746 //
1747 if (field->base_count() > 1) {
1748 for (BaseIterator i(field); i.has_next(); i.next()) {
1749 PointsToNode* base = i.get();
1750 // Don't take into account LocalVar nodes which
1751 // may point to only one object which should be also
1752 // this field's base by now.
1753 if (base->is_JavaObject() && base != jobj) {
1754 // Mark all bases.
1755 jobj->set_scalar_replaceable(false);
1756 base->set_scalar_replaceable(false);
1757 }
1758 }
1759 }
1760 }
1761 }
1762
1763 #ifdef ASSERT
1764 void ConnectionGraph::verify_connection_graph(
1765 GrowableArray<PointsToNode*>& ptnodes_worklist,
1766 GrowableArray<JavaObjectNode*>& non_escaped_worklist,
1767 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1768 GrowableArray<Node*>& addp_worklist) {
1769 // Verify that graph is complete - no new edges could be added.
1770 int java_objects_length = java_objects_worklist.length();
1771 int non_escaped_length = non_escaped_worklist.length();
1772 int new_edges = 0;
1773 for (int next = 0; next < java_objects_length; ++next) {
1774 JavaObjectNode* ptn = java_objects_worklist.at(next);
1775 new_edges += add_java_object_edges(ptn, true);
1776 }
1777 assert(new_edges == 0, "graph was not complete");
1778 // Verify that escape state is final.
1779 int length = non_escaped_worklist.length();
1780 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist);
1781 assert((non_escaped_length == non_escaped_worklist.length()) &&
1782 (non_escaped_length == length) &&
1783 (_worklist.length() == 0), "escape state was not final");
1784
1785 // Verify fields information.
1786 int addp_length = addp_worklist.length();
1787 for (int next = 0; next < addp_length; ++next ) {
1788 Node* n = addp_worklist.at(next);
1789 FieldNode* field = ptnode_adr(n->_idx)->as_Field();
1790 if (field->is_oop()) {
1791 // Verify that field has all bases
1792 Node* base = get_addp_base(n);
1793 PointsToNode* ptn = ptnode_adr(base->_idx);
1794 if (ptn->is_JavaObject()) {
1795 assert(field->has_base(ptn->as_JavaObject()), "sanity");
1796 } else {
1797 assert(ptn->is_LocalVar(), "sanity");
1798 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1799 PointsToNode* e = i.get();
1800 if (e->is_JavaObject()) {
1801 assert(field->has_base(e->as_JavaObject()), "sanity");
1802 }
1803 }
1804 }
1805 // Verify that all fields have initializing values.
1806 if (field->edge_count() == 0) {
1807 tty->print_cr("----------field does not have references----------");
1808 field->dump();
1809 for (BaseIterator i(field); i.has_next(); i.next()) {
1810 PointsToNode* base = i.get();
1811 tty->print_cr("----------field has next base---------------------");
1812 base->dump();
1813 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) {
1814 tty->print_cr("----------base has fields-------------------------");
1815 for (EdgeIterator j(base); j.has_next(); j.next()) {
1816 j.get()->dump();
1817 }
1818 tty->print_cr("----------base has references---------------------");
1819 for (UseIterator j(base); j.has_next(); j.next()) {
1820 j.get()->dump();
1821 }
1822 }
1823 }
1824 for (UseIterator i(field); i.has_next(); i.next()) {
1825 i.get()->dump();
1826 }
1827 assert(field->edge_count() > 0, "sanity");
1828 }
1829 }
1830 }
1831 }
1832 #endif
1833
1834 // Optimize ideal graph.
1835 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist,
1836 GrowableArray<Node*>& storestore_worklist) {
1837 Compile* C = _compile;
1838 PhaseIterGVN* igvn = _igvn;
1839 if (EliminateLocks) {
1840 // Mark locks before changing ideal graph.
1841 int cnt = C->macro_count();
1842 for( int i=0; i < cnt; i++ ) {
1843 Node *n = C->macro_node(i);
1844 if (n->is_AbstractLock()) { // Lock and Unlock nodes
1845 AbstractLockNode* alock = n->as_AbstractLock();
1846 if (!alock->is_non_esc_obj()) {
1847 if (not_global_escape(alock->obj_node())) {
1848 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity");
1849 // The lock could be marked eliminated by lock coarsening
1850 // code during first IGVN before EA. Replace coarsened flag
1851 // to eliminate all associated locks/unlocks.
1852 #ifdef ASSERT
1853 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3");
1854 #endif
1855 alock->set_non_esc_obj();
1856 }
1857 }
1858 }
1859 }
1860 }
1861
1862 if (OptimizePtrCompare) {
1863 // Add ConI(#CC_GT) and ConI(#CC_EQ).
1864 _pcmp_neq = igvn->makecon(TypeInt::CC_GT);
1865 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ);
1866 // Optimize objects compare.
1867 while (ptr_cmp_worklist.length() != 0) {
1868 Node *n = ptr_cmp_worklist.pop();
1869 Node *res = optimize_ptr_compare(n);
1870 if (res != NULL) {
1871 #ifndef PRODUCT
1872 if (PrintOptimizePtrCompare) {
1873 tty->print_cr("++++ Replaced: %d %s(%d,%d) --> %s", n->_idx, (n->Opcode() == Op_CmpP ? "CmpP" : "CmpN"), n->in(1)->_idx, n->in(2)->_idx, (res == _pcmp_eq ? "EQ" : "NotEQ"));
1874 if (Verbose) {
1875 n->dump(1);
1876 }
1877 }
1878 #endif
1879 igvn->replace_node(n, res);
1880 }
1881 }
1882 // cleanup
1883 if (_pcmp_neq->outcnt() == 0)
1884 igvn->hash_delete(_pcmp_neq);
1885 if (_pcmp_eq->outcnt() == 0)
1886 igvn->hash_delete(_pcmp_eq);
1887 }
1888
1889 // For MemBarStoreStore nodes added in library_call.cpp, check
1890 // escape status of associated AllocateNode and optimize out
1891 // MemBarStoreStore node if the allocated object never escapes.
1892 while (storestore_worklist.length() != 0) {
1893 Node *n = storestore_worklist.pop();
1894 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore();
1895 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0);
1896 assert (alloc->is_Allocate(), "storestore should point to AllocateNode");
1897 if (not_global_escape(alloc)) {
1898 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot);
1899 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory));
1900 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control));
1901 igvn->register_new_node_with_optimizer(mb);
1902 igvn->replace_node(storestore, mb);
1903 }
1904 }
1905 }
1906
1907 // Optimize objects compare.
1908 Node* ConnectionGraph::optimize_ptr_compare(Node* n) {
1909 assert(OptimizePtrCompare, "sanity");
1910 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx);
1911 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx);
1912 JavaObjectNode* jobj1 = unique_java_object(n->in(1));
1913 JavaObjectNode* jobj2 = unique_java_object(n->in(2));
1914 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity");
1915 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity");
1916
1917 // Check simple cases first.
1918 if (jobj1 != NULL) {
1919 if (jobj1->escape_state() == PointsToNode::NoEscape) {
1920 if (jobj1 == jobj2) {
1921 // Comparing the same not escaping object.
1922 return _pcmp_eq;
1923 }
1924 Node* obj = jobj1->ideal_node();
1925 // Comparing not escaping allocation.
1926 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
1927 !ptn2->points_to(jobj1)) {
1928 return _pcmp_neq; // This includes nullness check.
1929 }
1930 }
1931 }
1932 if (jobj2 != NULL) {
1933 if (jobj2->escape_state() == PointsToNode::NoEscape) {
1934 Node* obj = jobj2->ideal_node();
1935 // Comparing not escaping allocation.
1936 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
1937 !ptn1->points_to(jobj2)) {
1938 return _pcmp_neq; // This includes nullness check.
1939 }
1940 }
1941 }
1942 if (jobj1 != NULL && jobj1 != phantom_obj &&
1943 jobj2 != NULL && jobj2 != phantom_obj &&
1944 jobj1->ideal_node()->is_Con() &&
1945 jobj2->ideal_node()->is_Con()) {
1946 // Klass or String constants compare. Need to be careful with
1947 // compressed pointers - compare types of ConN and ConP instead of nodes.
1948 const Type* t1 = jobj1->ideal_node()->get_ptr_type();
1949 const Type* t2 = jobj2->ideal_node()->get_ptr_type();
1950 if (t1->make_ptr() == t2->make_ptr()) {
1951 return _pcmp_eq;
1952 } else {
1953 return _pcmp_neq;
1954 }
1955 }
1956 if (ptn1->meet(ptn2)) {
1957 return NULL; // Sets are not disjoint
1958 }
1959
1960 // Sets are disjoint.
1961 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj);
1962 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj);
1963 bool set1_has_null_ptr = ptn1->points_to(null_obj);
1964 bool set2_has_null_ptr = ptn2->points_to(null_obj);
1965 if (set1_has_unknown_ptr && set2_has_null_ptr ||
1966 set2_has_unknown_ptr && set1_has_null_ptr) {
1967 // Check nullness of unknown object.
1968 return NULL;
1969 }
1970
1971 // Disjointness by itself is not sufficient since
1972 // alias analysis is not complete for escaped objects.
1973 // Disjoint sets are definitely unrelated only when
1974 // at least one set has only not escaping allocations.
1975 if (!set1_has_unknown_ptr && !set1_has_null_ptr) {
1976 if (ptn1->non_escaping_allocation()) {
1977 return _pcmp_neq;
1978 }
1979 }
1980 if (!set2_has_unknown_ptr && !set2_has_null_ptr) {
1981 if (ptn2->non_escaping_allocation()) {
1982 return _pcmp_neq;
1983 }
1984 }
1985 return NULL;
1986 }
1987
1988 // Connection Graph constuction functions.
1989
1990 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) {
1991 PointsToNode* ptadr = _nodes.at(n->_idx);
1992 if (ptadr != NULL) {
1993 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity");
1994 return;
1995 }
1996 Compile* C = _compile;
1997 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es);
1998 _nodes.at_put(n->_idx, ptadr);
1999 }
2000
2001 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) {
2002 PointsToNode* ptadr = _nodes.at(n->_idx);
2003 if (ptadr != NULL) {
2004 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity");
2005 return;
2006 }
2007 Compile* C = _compile;
2008 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es);
2009 _nodes.at_put(n->_idx, ptadr);
2010 }
2011
2012 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) {
2013 PointsToNode* ptadr = _nodes.at(n->_idx);
2014 if (ptadr != NULL) {
2015 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity");
2016 return;
2017 }
2018 bool unsafe = false;
2019 bool is_oop = is_oop_field(n, offset, &unsafe);
2020 if (unsafe) {
2021 es = PointsToNode::GlobalEscape;
2022 }
2023 Compile* C = _compile;
2024 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop);
2025 _nodes.at_put(n->_idx, field);
2026 }
2027
2028 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es,
2029 PointsToNode* src, PointsToNode* dst) {
2030 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar");
2031 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL");
2032 PointsToNode* ptadr = _nodes.at(n->_idx);
2033 if (ptadr != NULL) {
2034 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity");
2035 return;
2036 }
2037 Compile* C = _compile;
2038 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es);
2039 _nodes.at_put(n->_idx, ptadr);
2040 // Add edge from arraycopy node to source object.
2041 (void)add_edge(ptadr, src);
2042 src->set_arraycopy_src();
2043 // Add edge from destination object to arraycopy node.
2044 (void)add_edge(dst, ptadr);
2045 dst->set_arraycopy_dst();
2046 }
2047
2048 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) {
2049 const Type* adr_type = n->as_AddP()->bottom_type();
2050 BasicType bt = T_INT;
2051 if (offset == Type::OffsetBot) {
2052 // Check only oop fields.
2053 if (!adr_type->isa_aryptr() ||
2054 (adr_type->isa_aryptr()->klass() == NULL) ||
2055 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) {
2056 // OffsetBot is used to reference array's element. Ignore first AddP.
2057 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) {
2058 bt = T_OBJECT;
2059 }
2060 }
2061 } else if (offset != oopDesc::klass_offset_in_bytes()) {
2062 if (adr_type->isa_instptr()) {
2063 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field();
2064 if (field != NULL) {
2065 bt = field->layout_type();
2066 } else {
2067 // Check for unsafe oop field access
2068 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN)) {
2069 bt = T_OBJECT;
2070 (*unsafe) = true;
2071 }
2072 }
2073 } else if (adr_type->isa_aryptr()) {
2074 if (offset == arrayOopDesc::length_offset_in_bytes()) {
2075 // Ignore array length load.
2076 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) {
2077 // Ignore first AddP.
2078 } else {
2079 const Type* elemtype = adr_type->isa_aryptr()->elem();
2080 bt = elemtype->array_element_basic_type();
2081 }
2082 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) {
2083 // Allocation initialization, ThreadLocal field access, unsafe access
2084 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN)) {
2085 bt = T_OBJECT;
2086 }
2087 }
2088 }
2089 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY);
2090 }
2091
2092 // Returns unique pointed java object or NULL.
2093 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) {
2094 assert(!_collecting, "should not call when contructed graph");
2095 // If the node was created after the escape computation we can't answer.
2096 uint idx = n->_idx;
2097 if (idx >= nodes_size()) {
2098 return NULL;
2099 }
2100 PointsToNode* ptn = ptnode_adr(idx);
2101 if (ptn->is_JavaObject()) {
2102 return ptn->as_JavaObject();
2103 }
2104 assert(ptn->is_LocalVar(), "sanity");
2105 // Check all java objects it points to.
2106 JavaObjectNode* jobj = NULL;
2107 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2108 PointsToNode* e = i.get();
2109 if (e->is_JavaObject()) {
2110 if (jobj == NULL) {
2111 jobj = e->as_JavaObject();
2112 } else if (jobj != e) {
2113 return NULL;
2114 }
2115 }
2116 }
2117 return jobj;
2118 }
2119
2120 // Return true if this node points only to non-escaping allocations.
2121 bool PointsToNode::non_escaping_allocation() {
2122 if (is_JavaObject()) {
2123 Node* n = ideal_node();
2124 if (n->is_Allocate() || n->is_CallStaticJava()) {
2125 return (escape_state() == PointsToNode::NoEscape);
2126 } else {
2127 return false;
2128 }
2129 }
2130 assert(is_LocalVar(), "sanity");
2131 // Check all java objects it points to.
2132 for (EdgeIterator i(this); i.has_next(); i.next()) {
2133 PointsToNode* e = i.get();
2134 if (e->is_JavaObject()) {
2135 Node* n = e->ideal_node();
2136 if ((e->escape_state() != PointsToNode::NoEscape) ||
2137 !(n->is_Allocate() || n->is_CallStaticJava())) {
2138 return false;
2139 }
2140 }
2141 }
2142 return true;
2143 }
2144
2145 // Return true if we know the node does not escape globally.
2146 bool ConnectionGraph::not_global_escape(Node *n) {
2147 assert(!_collecting, "should not call during graph construction");
2148 // If the node was created after the escape computation we can't answer.
2149 uint idx = n->_idx;
2150 if (idx >= nodes_size()) {
2151 return false;
2152 }
2153 PointsToNode* ptn = ptnode_adr(idx);
2154 PointsToNode::EscapeState es = ptn->escape_state();
2155 // If we have already computed a value, return it.
2156 if (es >= PointsToNode::GlobalEscape)
2157 return false;
2158 if (ptn->is_JavaObject()) {
2159 return true; // (es < PointsToNode::GlobalEscape);
2160 }
2161 assert(ptn->is_LocalVar(), "sanity");
2162 // Check all java objects it points to.
2163 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2164 if (i.get()->escape_state() >= PointsToNode::GlobalEscape)
2165 return false;
2166 }
2167 return true;
2168 }
2169
2170
2171 // Helper functions
2172
2173 // Return true if this node points to specified node or nodes it points to.
2174 bool PointsToNode::points_to(JavaObjectNode* ptn) const {
2175 if (is_JavaObject()) {
2176 return (this == ptn);
2177 }
2178 assert(is_LocalVar() || is_Field(), "sanity");
2179 for (EdgeIterator i(this); i.has_next(); i.next()) {
2180 if (i.get() == ptn)
2181 return true;
2182 }
2183 return false;
2184 }
2185
2186 // Return true if one node points to an other.
2187 bool PointsToNode::meet(PointsToNode* ptn) {
2188 if (this == ptn) {
2189 return true;
2190 } else if (ptn->is_JavaObject()) {
2191 return this->points_to(ptn->as_JavaObject());
2192 } else if (this->is_JavaObject()) {
2193 return ptn->points_to(this->as_JavaObject());
2194 }
2195 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity");
2196 int ptn_count = ptn->edge_count();
2197 for (EdgeIterator i(this); i.has_next(); i.next()) {
2198 PointsToNode* this_e = i.get();
2199 for (int j = 0; j < ptn_count; j++) {
2200 if (this_e == ptn->edge(j))
2201 return true;
2202 }
2203 }
2204 return false;
2205 }
2206
2207 #ifdef ASSERT
2208 // Return true if bases point to this java object.
2209 bool FieldNode::has_base(JavaObjectNode* jobj) const {
2210 for (BaseIterator i(this); i.has_next(); i.next()) {
2211 if (i.get() == jobj)
2212 return true;
2213 }
2214 return false;
2215 }
2216 #endif
2217
2218 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
2219 const Type *adr_type = phase->type(adr);
2220 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL &&
2221 adr->in(AddPNode::Address)->is_Proj() &&
2222 adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
2223 // We are computing a raw address for a store captured by an Initialize
2224 // compute an appropriate address type. AddP cases #3 and #5 (see below).
2225 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
2226 assert(offs != Type::OffsetBot ||
2227 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
2228 "offset must be a constant or it is initialization of array");
2229 return offs;
2230 }
2231 const TypePtr *t_ptr = adr_type->isa_ptr();
2232 assert(t_ptr != NULL, "must be a pointer type");
2233 return t_ptr->offset();
2234 }
2235
2236 Node* ConnectionGraph::get_addp_base(Node *addp) {
2237 assert(addp->is_AddP(), "must be AddP");
2238 //
2239 // AddP cases for Base and Address inputs:
2240 // case #1. Direct object's field reference:
2241 // Allocate
2242 // |
2243 // Proj #5 ( oop result )
2244 // |
2245 // CheckCastPP (cast to instance type)
2246 // | |
2247 // AddP ( base == address )
2248 //
2249 // case #2. Indirect object's field reference:
2250 // Phi
2251 // |
2252 // CastPP (cast to instance type)
2253 // | |
2254 // AddP ( base == address )
2255 //
2256 // case #3. Raw object's field reference for Initialize node:
2257 // Allocate
2258 // |
2259 // Proj #5 ( oop result )
2260 // top |
2261 // \ |
2262 // AddP ( base == top )
2263 //
2264 // case #4. Array's element reference:
2265 // {CheckCastPP | CastPP}
2266 // | | |
2267 // | AddP ( array's element offset )
2268 // | |
2269 // AddP ( array's offset )
2270 //
2271 // case #5. Raw object's field reference for arraycopy stub call:
2272 // The inline_native_clone() case when the arraycopy stub is called
2273 // after the allocation before Initialize and CheckCastPP nodes.
2274 // Allocate
2275 // |
2276 // Proj #5 ( oop result )
2277 // | |
2278 // AddP ( base == address )
2279 //
2280 // case #6. Constant Pool, ThreadLocal, CastX2P or
2281 // Raw object's field reference:
2282 // {ConP, ThreadLocal, CastX2P, raw Load}
2283 // top |
2284 // \ |
2285 // AddP ( base == top )
2286 //
2287 // case #7. Klass's field reference.
2288 // LoadKlass
2289 // | |
2290 // AddP ( base == address )
2291 //
2292 // case #8. narrow Klass's field reference.
2293 // LoadNKlass
2294 // |
2295 // DecodeN
2296 // | |
2297 // AddP ( base == address )
2298 //
2299 Node *base = addp->in(AddPNode::Base);
2300 if (base->uncast()->is_top()) { // The AddP case #3 and #6.
2301 base = addp->in(AddPNode::Address);
2302 while (base->is_AddP()) {
2303 // Case #6 (unsafe access) may have several chained AddP nodes.
2304 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only");
2305 base = base->in(AddPNode::Address);
2306 }
2307 Node* uncast_base = base->uncast();
2308 int opcode = uncast_base->Opcode();
2309 assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
2310 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
2311 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) ||
2312 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity");
2313 }
2314 return base;
2315 }
2316
2317 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) {
2318 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
2319 Node* addp2 = addp->raw_out(0);
2320 if (addp->outcnt() == 1 && addp2->is_AddP() &&
2321 addp2->in(AddPNode::Base) == n &&
2322 addp2->in(AddPNode::Address) == addp) {
2323 assert(addp->in(AddPNode::Base) == n, "expecting the same base");
2324 //
2325 // Find array's offset to push it on worklist first and
2326 // as result process an array's element offset first (pushed second)
2327 // to avoid CastPP for the array's offset.
2328 // Otherwise the inserted CastPP (LocalVar) will point to what
2329 // the AddP (Field) points to. Which would be wrong since
2330 // the algorithm expects the CastPP has the same point as
2331 // as AddP's base CheckCastPP (LocalVar).
2332 //
2333 // ArrayAllocation
2334 // |
2335 // CheckCastPP
2336 // |
2337 // memProj (from ArrayAllocation CheckCastPP)
2338 // | ||
2339 // | || Int (element index)
2340 // | || | ConI (log(element size))
2341 // | || | /
2342 // | || LShift
2343 // | || /
2344 // | AddP (array's element offset)
2345 // | |
2346 // | | ConI (array's offset: #12(32-bits) or #24(64-bits))
2347 // | / /
2348 // AddP (array's offset)
2349 // |
2350 // Load/Store (memory operation on array's element)
2351 //
2352 return addp2;
2353 }
2354 return NULL;
2355 }
2356
2357 //
2358 // Adjust the type and inputs of an AddP which computes the
2359 // address of a field of an instance
2360 //
2361 bool ConnectionGraph::split_AddP(Node *addp, Node *base) {
2362 PhaseGVN* igvn = _igvn;
2363 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
2364 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
2365 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
2366 if (t == NULL) {
2367 // We are computing a raw address for a store captured by an Initialize
2368 // compute an appropriate address type (cases #3 and #5).
2369 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
2370 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
2371 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
2372 assert(offs != Type::OffsetBot, "offset must be a constant");
2373 t = base_t->add_offset(offs)->is_oopptr();
2374 }
2375 int inst_id = base_t->instance_id();
2376 assert(!t->is_known_instance() || t->instance_id() == inst_id,
2377 "old type must be non-instance or match new type");
2378
2379 // The type 't' could be subclass of 'base_t'.
2380 // As result t->offset() could be large then base_t's size and it will
2381 // cause the failure in add_offset() with narrow oops since TypeOopPtr()
2382 // constructor verifies correctness of the offset.
2383 //
2384 // It could happened on subclass's branch (from the type profiling
2385 // inlining) which was not eliminated during parsing since the exactness
2386 // of the allocation type was not propagated to the subclass type check.
2387 //
2388 // Or the type 't' could be not related to 'base_t' at all.
2389 // It could happened when CHA type is different from MDO type on a dead path
2390 // (for example, from instanceof check) which is not collapsed during parsing.
2391 //
2392 // Do nothing for such AddP node and don't process its users since
2393 // this code branch will go away.
2394 //
2395 if (!t->is_known_instance() &&
2396 !base_t->klass()->is_subtype_of(t->klass())) {
2397 return false; // bail out
2398 }
2399 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
2400 // Do NOT remove the next line: ensure a new alias index is allocated
2401 // for the instance type. Note: C++ will not remove it since the call
2402 // has side effect.
2403 int alias_idx = _compile->get_alias_index(tinst);
2404 igvn->set_type(addp, tinst);
2405 // record the allocation in the node map
2406 set_map(addp, get_map(base->_idx));
2407 // Set addp's Base and Address to 'base'.
2408 Node *abase = addp->in(AddPNode::Base);
2409 Node *adr = addp->in(AddPNode::Address);
2410 if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
2411 adr->in(0)->_idx == (uint)inst_id) {
2412 // Skip AddP cases #3 and #5.
2413 } else {
2414 assert(!abase->is_top(), "sanity"); // AddP case #3
2415 if (abase != base) {
2416 igvn->hash_delete(addp);
2417 addp->set_req(AddPNode::Base, base);
2418 if (abase == adr) {
2419 addp->set_req(AddPNode::Address, base);
2420 } else {
2421 // AddP case #4 (adr is array's element offset AddP node)
2422 #ifdef ASSERT
2423 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
2424 assert(adr->is_AddP() && atype != NULL &&
2425 atype->instance_id() == inst_id, "array's element offset should be processed first");
2426 #endif
2427 }
2428 igvn->hash_insert(addp);
2429 }
2430 }
2431 // Put on IGVN worklist since at least addp's type was changed above.
2432 record_for_optimizer(addp);
2433 return true;
2434 }
2435
2436 //
2437 // Create a new version of orig_phi if necessary. Returns either the newly
2438 // created phi or an existing phi. Sets create_new to indicate whether a new
2439 // phi was created. Cache the last newly created phi in the node map.
2440 //
2441 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) {
2442 Compile *C = _compile;
2443 PhaseGVN* igvn = _igvn;
2444 new_created = false;
2445 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
2446 // nothing to do if orig_phi is bottom memory or matches alias_idx
2447 if (phi_alias_idx == alias_idx) {
2448 return orig_phi;
2449 }
2450 // Have we recently created a Phi for this alias index?
2451 PhiNode *result = get_map_phi(orig_phi->_idx);
2452 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
2453 return result;
2454 }
2455 // Previous check may fail when the same wide memory Phi was split into Phis
2456 // for different memory slices. Search all Phis for this region.
2457 if (result != NULL) {
2458 Node* region = orig_phi->in(0);
2459 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2460 Node* phi = region->fast_out(i);
2461 if (phi->is_Phi() &&
2462 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
2463 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
2464 return phi->as_Phi();
2465 }
2466 }
2467 }
2468 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) {
2469 if (C->do_escape_analysis() == true && !C->failing()) {
2470 // Retry compilation without escape analysis.
2471 // If this is the first failure, the sentinel string will "stick"
2472 // to the Compile object, and the C2Compiler will see it and retry.
2473 C->record_failure(C2Compiler::retry_no_escape_analysis());
2474 }
2475 return NULL;
2476 }
2477 orig_phi_worklist.append_if_missing(orig_phi);
2478 const TypePtr *atype = C->get_adr_type(alias_idx);
2479 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
2480 C->copy_node_notes_to(result, orig_phi);
2481 igvn->set_type(result, result->bottom_type());
2482 record_for_optimizer(result);
2483 set_map(orig_phi, result);
2484 new_created = true;
2485 return result;
2486 }
2487
2488 //
2489 // Return a new version of Memory Phi "orig_phi" with the inputs having the
2490 // specified alias index.
2491 //
2492 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) {
2493 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
2494 Compile *C = _compile;
2495 PhaseGVN* igvn = _igvn;
2496 bool new_phi_created;
2497 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created);
2498 if (!new_phi_created) {
2499 return result;
2500 }
2501 GrowableArray<PhiNode *> phi_list;
2502 GrowableArray<uint> cur_input;
2503 PhiNode *phi = orig_phi;
2504 uint idx = 1;
2505 bool finished = false;
2506 while(!finished) {
2507 while (idx < phi->req()) {
2508 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist);
2509 if (mem != NULL && mem->is_Phi()) {
2510 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created);
2511 if (new_phi_created) {
2512 // found an phi for which we created a new split, push current one on worklist and begin
2513 // processing new one
2514 phi_list.push(phi);
2515 cur_input.push(idx);
2516 phi = mem->as_Phi();
2517 result = newphi;
2518 idx = 1;
2519 continue;
2520 } else {
2521 mem = newphi;
2522 }
2523 }
2524 if (C->failing()) {
2525 return NULL;
2526 }
2527 result->set_req(idx++, mem);
2528 }
2529 #ifdef ASSERT
2530 // verify that the new Phi has an input for each input of the original
2531 assert( phi->req() == result->req(), "must have same number of inputs.");
2532 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
2533 #endif
2534 // Check if all new phi's inputs have specified alias index.
2535 // Otherwise use old phi.
2536 for (uint i = 1; i < phi->req(); i++) {
2537 Node* in = result->in(i);
2538 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
2539 }
2540 // we have finished processing a Phi, see if there are any more to do
2541 finished = (phi_list.length() == 0 );
2542 if (!finished) {
2543 phi = phi_list.pop();
2544 idx = cur_input.pop();
2545 PhiNode *prev_result = get_map_phi(phi->_idx);
2546 prev_result->set_req(idx++, result);
2547 result = prev_result;
2548 }
2549 }
2550 return result;
2551 }
2552
2553 //
2554 // The next methods are derived from methods in MemNode.
2555 //
2556 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
2557 Node *mem = mmem;
2558 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
2559 // means an array I have not precisely typed yet. Do not do any
2560 // alias stuff with it any time soon.
2561 if (toop->base() != Type::AnyPtr &&
2562 !(toop->klass() != NULL &&
2563 toop->klass()->is_java_lang_Object() &&
2564 toop->offset() == Type::OffsetBot)) {
2565 mem = mmem->memory_at(alias_idx);
2566 // Update input if it is progress over what we have now
2567 }
2568 return mem;
2569 }
2570
2571 //
2572 // Move memory users to their memory slices.
2573 //
2574 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) {
2575 Compile* C = _compile;
2576 PhaseGVN* igvn = _igvn;
2577 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
2578 assert(tp != NULL, "ptr type");
2579 int alias_idx = C->get_alias_index(tp);
2580 int general_idx = C->get_general_index(alias_idx);
2581
2582 // Move users first
2583 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2584 Node* use = n->fast_out(i);
2585 if (use->is_MergeMem()) {
2586 MergeMemNode* mmem = use->as_MergeMem();
2587 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
2588 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
2589 continue; // Nothing to do
2590 }
2591 // Replace previous general reference to mem node.
2592 uint orig_uniq = C->unique();
2593 Node* m = find_inst_mem(n, general_idx, orig_phis);
2594 assert(orig_uniq == C->unique(), "no new nodes");
2595 mmem->set_memory_at(general_idx, m);
2596 --imax;
2597 --i;
2598 } else if (use->is_MemBar()) {
2599 assert(!use->is_Initialize(), "initializing stores should not be moved");
2600 if (use->req() > MemBarNode::Precedent &&
2601 use->in(MemBarNode::Precedent) == n) {
2602 // Don't move related membars.
2603 record_for_optimizer(use);
2604 continue;
2605 }
2606 tp = use->as_MemBar()->adr_type()->isa_ptr();
2607 if (tp != NULL && C->get_alias_index(tp) == alias_idx ||
2608 alias_idx == general_idx) {
2609 continue; // Nothing to do
2610 }
2611 // Move to general memory slice.
2612 uint orig_uniq = C->unique();
2613 Node* m = find_inst_mem(n, general_idx, orig_phis);
2614 assert(orig_uniq == C->unique(), "no new nodes");
2615 igvn->hash_delete(use);
2616 imax -= use->replace_edge(n, m);
2617 igvn->hash_insert(use);
2618 record_for_optimizer(use);
2619 --i;
2620 #ifdef ASSERT
2621 } else if (use->is_Mem()) {
2622 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) {
2623 // Don't move related cardmark.
2624 continue;
2625 }
2626 // Memory nodes should have new memory input.
2627 tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
2628 assert(tp != NULL, "ptr type");
2629 int idx = C->get_alias_index(tp);
2630 assert(get_map(use->_idx) != NULL || idx == alias_idx,
2631 "Following memory nodes should have new memory input or be on the same memory slice");
2632 } else if (use->is_Phi()) {
2633 // Phi nodes should be split and moved already.
2634 tp = use->as_Phi()->adr_type()->isa_ptr();
2635 assert(tp != NULL, "ptr type");
2636 int idx = C->get_alias_index(tp);
2637 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
2638 } else {
2639 use->dump();
2640 assert(false, "should not be here");
2641 #endif
2642 }
2643 }
2644 }
2645
2646 //
2647 // Search memory chain of "mem" to find a MemNode whose address
2648 // is the specified alias index.
2649 //
2650 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) {
2651 if (orig_mem == NULL)
2652 return orig_mem;
2653 Compile* C = _compile;
2654 PhaseGVN* igvn = _igvn;
2655 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
2656 bool is_instance = (toop != NULL) && toop->is_known_instance();
2657 Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
2658 Node *prev = NULL;
2659 Node *result = orig_mem;
2660 while (prev != result) {
2661 prev = result;
2662 if (result == start_mem)
2663 break; // hit one of our sentinels
2664 if (result->is_Mem()) {
2665 const Type *at = igvn->type(result->in(MemNode::Address));
2666 if (at == Type::TOP)
2667 break; // Dead
2668 assert (at->isa_ptr() != NULL, "pointer type required.");
2669 int idx = C->get_alias_index(at->is_ptr());
2670 if (idx == alias_idx)
2671 break; // Found
2672 if (!is_instance && (at->isa_oopptr() == NULL ||
2673 !at->is_oopptr()->is_known_instance())) {
2674 break; // Do not skip store to general memory slice.
2675 }
2676 result = result->in(MemNode::Memory);
2677 }
2678 if (!is_instance)
2679 continue; // don't search further for non-instance types
2680 // skip over a call which does not affect this memory slice
2681 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
2682 Node *proj_in = result->in(0);
2683 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
2684 break; // hit one of our sentinels
2685 } else if (proj_in->is_Call()) {
2686 // ArrayCopy node processed here as well
2687 CallNode *call = proj_in->as_Call();
2688 if (!call->may_modify(toop, igvn)) {
2689 result = call->in(TypeFunc::Memory);
2690 }
2691 } else if (proj_in->is_Initialize()) {
2692 AllocateNode* alloc = proj_in->as_Initialize()->allocation();
2693 // Stop if this is the initialization for the object instance which
2694 // which contains this memory slice, otherwise skip over it.
2695 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) {
2696 result = proj_in->in(TypeFunc::Memory);
2697 }
2698 } else if (proj_in->is_MemBar()) {
2699 if (proj_in->in(TypeFunc::Memory)->is_MergeMem() &&
2700 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->is_Proj() &&
2701 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->is_ArrayCopy()) {
2702 // clone
2703 ArrayCopyNode* ac = proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->as_ArrayCopy();
2704 if (ac->may_modify(toop, igvn)) {
2705 break;
2706 }
2707 }
2708 result = proj_in->in(TypeFunc::Memory);
2709 }
2710 } else if (result->is_MergeMem()) {
2711 MergeMemNode *mmem = result->as_MergeMem();
2712 result = step_through_mergemem(mmem, alias_idx, toop);
2713 if (result == mmem->base_memory()) {
2714 // Didn't find instance memory, search through general slice recursively.
2715 result = mmem->memory_at(C->get_general_index(alias_idx));
2716 result = find_inst_mem(result, alias_idx, orig_phis);
2717 if (C->failing()) {
2718 return NULL;
2719 }
2720 mmem->set_memory_at(alias_idx, result);
2721 }
2722 } else if (result->is_Phi() &&
2723 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
2724 Node *un = result->as_Phi()->unique_input(igvn);
2725 if (un != NULL) {
2726 orig_phis.append_if_missing(result->as_Phi());
2727 result = un;
2728 } else {
2729 break;
2730 }
2731 } else if (result->is_ClearArray()) {
2732 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) {
2733 // Can not bypass initialization of the instance
2734 // we are looking for.
2735 break;
2736 }
2737 // Otherwise skip it (the call updated 'result' value).
2738 } else if (result->Opcode() == Op_SCMemProj) {
2739 Node* mem = result->in(0);
2740 Node* adr = NULL;
2741 if (mem->is_LoadStore()) {
2742 adr = mem->in(MemNode::Address);
2743 } else {
2744 assert(mem->Opcode() == Op_EncodeISOArray ||
2745 mem->Opcode() == Op_StrCompressedCopy, "sanity");
2746 adr = mem->in(3); // Memory edge corresponds to destination array
2747 }
2748 const Type *at = igvn->type(adr);
2749 if (at != Type::TOP) {
2750 assert(at->isa_ptr() != NULL, "pointer type required.");
2751 int idx = C->get_alias_index(at->is_ptr());
2752 if (idx == alias_idx) {
2753 // Assert in debug mode
2754 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
2755 break; // In product mode return SCMemProj node
2756 }
2757 }
2758 result = mem->in(MemNode::Memory);
2759 } else if (result->Opcode() == Op_StrInflatedCopy) {
2760 Node* adr = result->in(3); // Memory edge corresponds to destination array
2761 const Type *at = igvn->type(adr);
2762 if (at != Type::TOP) {
2763 assert(at->isa_ptr() != NULL, "pointer type required.");
2764 int idx = C->get_alias_index(at->is_ptr());
2765 if (idx == alias_idx) {
2766 // Assert in debug mode
2767 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
2768 break; // In product mode return SCMemProj node
2769 }
2770 }
2771 result = result->in(MemNode::Memory);
2772 }
2773 }
2774 if (result->is_Phi()) {
2775 PhiNode *mphi = result->as_Phi();
2776 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
2777 const TypePtr *t = mphi->adr_type();
2778 if (!is_instance) {
2779 // Push all non-instance Phis on the orig_phis worklist to update inputs
2780 // during Phase 4 if needed.
2781 orig_phis.append_if_missing(mphi);
2782 } else if (C->get_alias_index(t) != alias_idx) {
2783 // Create a new Phi with the specified alias index type.
2784 result = split_memory_phi(mphi, alias_idx, orig_phis);
2785 }
2786 }
2787 // the result is either MemNode, PhiNode, InitializeNode.
2788 return result;
2789 }
2790
2791 //
2792 // Convert the types of unescaped object to instance types where possible,
2793 // propagate the new type information through the graph, and update memory
2794 // edges and MergeMem inputs to reflect the new type.
2795 //
2796 // We start with allocations (and calls which may be allocations) on alloc_worklist.
2797 // The processing is done in 4 phases:
2798 //
2799 // Phase 1: Process possible allocations from alloc_worklist. Create instance
2800 // types for the CheckCastPP for allocations where possible.
2801 // Propagate the new types through users as follows:
2802 // casts and Phi: push users on alloc_worklist
2803 // AddP: cast Base and Address inputs to the instance type
2804 // push any AddP users on alloc_worklist and push any memnode
2805 // users onto memnode_worklist.
2806 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
2807 // search the Memory chain for a store with the appropriate type
2808 // address type. If a Phi is found, create a new version with
2809 // the appropriate memory slices from each of the Phi inputs.
2810 // For stores, process the users as follows:
2811 // MemNode: push on memnode_worklist
2812 // MergeMem: push on mergemem_worklist
2813 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
2814 // moving the first node encountered of each instance type to the
2815 // the input corresponding to its alias index.
2816 // appropriate memory slice.
2817 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
2818 //
2819 // In the following example, the CheckCastPP nodes are the cast of allocation
2820 // results and the allocation of node 29 is unescaped and eligible to be an
2821 // instance type.
2822 //
2823 // We start with:
2824 //
2825 // 7 Parm #memory
2826 // 10 ConI "12"
2827 // 19 CheckCastPP "Foo"
2828 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2829 // 29 CheckCastPP "Foo"
2830 // 30 AddP _ 29 29 10 Foo+12 alias_index=4
2831 //
2832 // 40 StoreP 25 7 20 ... alias_index=4
2833 // 50 StoreP 35 40 30 ... alias_index=4
2834 // 60 StoreP 45 50 20 ... alias_index=4
2835 // 70 LoadP _ 60 30 ... alias_index=4
2836 // 80 Phi 75 50 60 Memory alias_index=4
2837 // 90 LoadP _ 80 30 ... alias_index=4
2838 // 100 LoadP _ 80 20 ... alias_index=4
2839 //
2840 //
2841 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
2842 // and creating a new alias index for node 30. This gives:
2843 //
2844 // 7 Parm #memory
2845 // 10 ConI "12"
2846 // 19 CheckCastPP "Foo"
2847 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2848 // 29 CheckCastPP "Foo" iid=24
2849 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
2850 //
2851 // 40 StoreP 25 7 20 ... alias_index=4
2852 // 50 StoreP 35 40 30 ... alias_index=6
2853 // 60 StoreP 45 50 20 ... alias_index=4
2854 // 70 LoadP _ 60 30 ... alias_index=6
2855 // 80 Phi 75 50 60 Memory alias_index=4
2856 // 90 LoadP _ 80 30 ... alias_index=6
2857 // 100 LoadP _ 80 20 ... alias_index=4
2858 //
2859 // In phase 2, new memory inputs are computed for the loads and stores,
2860 // And a new version of the phi is created. In phase 4, the inputs to
2861 // node 80 are updated and then the memory nodes are updated with the
2862 // values computed in phase 2. This results in:
2863 //
2864 // 7 Parm #memory
2865 // 10 ConI "12"
2866 // 19 CheckCastPP "Foo"
2867 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2868 // 29 CheckCastPP "Foo" iid=24
2869 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
2870 //
2871 // 40 StoreP 25 7 20 ... alias_index=4
2872 // 50 StoreP 35 7 30 ... alias_index=6
2873 // 60 StoreP 45 40 20 ... alias_index=4
2874 // 70 LoadP _ 50 30 ... alias_index=6
2875 // 80 Phi 75 40 60 Memory alias_index=4
2876 // 120 Phi 75 50 50 Memory alias_index=6
2877 // 90 LoadP _ 120 30 ... alias_index=6
2878 // 100 LoadP _ 80 20 ... alias_index=4
2879 //
2880 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist, GrowableArray<ArrayCopyNode*> &arraycopy_worklist) {
2881 GrowableArray<Node *> memnode_worklist;
2882 GrowableArray<PhiNode *> orig_phis;
2883 PhaseIterGVN *igvn = _igvn;
2884 uint new_index_start = (uint) _compile->num_alias_types();
2885 Arena* arena = Thread::current()->resource_area();
2886 VectorSet visited(arena);
2887 ideal_nodes.clear(); // Reset for use with set_map/get_map.
2888 uint unique_old = _compile->unique();
2889
2890 // Phase 1: Process possible allocations from alloc_worklist.
2891 // Create instance types for the CheckCastPP for allocations where possible.
2892 //
2893 // (Note: don't forget to change the order of the second AddP node on
2894 // the alloc_worklist if the order of the worklist processing is changed,
2895 // see the comment in find_second_addp().)
2896 //
2897 while (alloc_worklist.length() != 0) {
2898 Node *n = alloc_worklist.pop();
2899 uint ni = n->_idx;
2900 if (n->is_Call()) {
2901 CallNode *alloc = n->as_Call();
2902 // copy escape information to call node
2903 PointsToNode* ptn = ptnode_adr(alloc->_idx);
2904 PointsToNode::EscapeState es = ptn->escape_state();
2905 // We have an allocation or call which returns a Java object,
2906 // see if it is unescaped.
2907 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable())
2908 continue;
2909 // Find CheckCastPP for the allocate or for the return value of a call
2910 n = alloc->result_cast();
2911 if (n == NULL) { // No uses except Initialize node
2912 if (alloc->is_Allocate()) {
2913 // Set the scalar_replaceable flag for allocation
2914 // so it could be eliminated if it has no uses.
2915 alloc->as_Allocate()->_is_scalar_replaceable = true;
2916 }
2917 if (alloc->is_CallStaticJava()) {
2918 // Set the scalar_replaceable flag for boxing method
2919 // so it could be eliminated if it has no uses.
2920 alloc->as_CallStaticJava()->_is_scalar_replaceable = true;
2921 }
2922 continue;
2923 }
2924 if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
2925 assert(!alloc->is_Allocate(), "allocation should have unique type");
2926 continue;
2927 }
2928
2929 // The inline code for Object.clone() casts the allocation result to
2930 // java.lang.Object and then to the actual type of the allocated
2931 // object. Detect this case and use the second cast.
2932 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
2933 // the allocation result is cast to java.lang.Object and then
2934 // to the actual Array type.
2935 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
2936 && (alloc->is_AllocateArray() ||
2937 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
2938 Node *cast2 = NULL;
2939 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2940 Node *use = n->fast_out(i);
2941 if (use->is_CheckCastPP()) {
2942 cast2 = use;
2943 break;
2944 }
2945 }
2946 if (cast2 != NULL) {
2947 n = cast2;
2948 } else {
2949 // Non-scalar replaceable if the allocation type is unknown statically
2950 // (reflection allocation), the object can't be restored during
2951 // deoptimization without precise type.
2952 continue;
2953 }
2954 }
2955
2956 const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
2957 if (t == NULL)
2958 continue; // not a TypeOopPtr
2959 if (!t->klass_is_exact())
2960 continue; // not an unique type
2961
2962 if (alloc->is_Allocate()) {
2963 // Set the scalar_replaceable flag for allocation
2964 // so it could be eliminated.
2965 alloc->as_Allocate()->_is_scalar_replaceable = true;
2966 }
2967 if (alloc->is_CallStaticJava()) {
2968 // Set the scalar_replaceable flag for boxing method
2969 // so it could be eliminated.
2970 alloc->as_CallStaticJava()->_is_scalar_replaceable = true;
2971 }
2972 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state
2973 // in order for an object to be scalar-replaceable, it must be:
2974 // - a direct allocation (not a call returning an object)
2975 // - non-escaping
2976 // - eligible to be a unique type
2977 // - not determined to be ineligible by escape analysis
2978 set_map(alloc, n);
2979 set_map(n, alloc);
2980 const TypeOopPtr* tinst = t->cast_to_instance_id(ni);
2981 igvn->hash_delete(n);
2982 igvn->set_type(n, tinst);
2983 n->raise_bottom_type(tinst);
2984 igvn->hash_insert(n);
2985 record_for_optimizer(n);
2986 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) {
2987
2988 // First, put on the worklist all Field edges from Connection Graph
2989 // which is more accurate than putting immediate users from Ideal Graph.
2990 for (EdgeIterator e(ptn); e.has_next(); e.next()) {
2991 PointsToNode* tgt = e.get();
2992 if (tgt->is_Arraycopy()) {
2993 continue;
2994 }
2995 Node* use = tgt->ideal_node();
2996 assert(tgt->is_Field() && use->is_AddP(),
2997 "only AddP nodes are Field edges in CG");
2998 if (use->outcnt() > 0) { // Don't process dead nodes
2999 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
3000 if (addp2 != NULL) {
3001 assert(alloc->is_AllocateArray(),"array allocation was expected");
3002 alloc_worklist.append_if_missing(addp2);
3003 }
3004 alloc_worklist.append_if_missing(use);
3005 }
3006 }
3007
3008 // An allocation may have an Initialize which has raw stores. Scan
3009 // the users of the raw allocation result and push AddP users
3010 // on alloc_worklist.
3011 Node *raw_result = alloc->proj_out(TypeFunc::Parms);
3012 assert (raw_result != NULL, "must have an allocation result");
3013 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
3014 Node *use = raw_result->fast_out(i);
3015 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
3016 Node* addp2 = find_second_addp(use, raw_result);
3017 if (addp2 != NULL) {
3018 assert(alloc->is_AllocateArray(),"array allocation was expected");
3019 alloc_worklist.append_if_missing(addp2);
3020 }
3021 alloc_worklist.append_if_missing(use);
3022 } else if (use->is_MemBar()) {
3023 memnode_worklist.append_if_missing(use);
3024 }
3025 }
3026 }
3027 } else if (n->is_AddP()) {
3028 JavaObjectNode* jobj = unique_java_object(get_addp_base(n));
3029 if (jobj == NULL || jobj == phantom_obj) {
3030 #ifdef ASSERT
3031 ptnode_adr(get_addp_base(n)->_idx)->dump();
3032 ptnode_adr(n->_idx)->dump();
3033 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3034 #endif
3035 _compile->record_failure(C2Compiler::retry_no_escape_analysis());
3036 return;
3037 }
3038 Node *base = get_map(jobj->idx()); // CheckCastPP node
3039 if (!split_AddP(n, base)) continue; // wrong type from dead path
3040 } else if (n->is_Phi() ||
3041 n->is_CheckCastPP() ||
3042 n->is_EncodeP() ||
3043 n->is_DecodeN() ||
3044 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
3045 if (visited.test_set(n->_idx)) {
3046 assert(n->is_Phi(), "loops only through Phi's");
3047 continue; // already processed
3048 }
3049 JavaObjectNode* jobj = unique_java_object(n);
3050 if (jobj == NULL || jobj == phantom_obj) {
3051 #ifdef ASSERT
3052 ptnode_adr(n->_idx)->dump();
3053 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3054 #endif
3055 _compile->record_failure(C2Compiler::retry_no_escape_analysis());
3056 return;
3057 } else {
3058 Node *val = get_map(jobj->idx()); // CheckCastPP node
3059 TypeNode *tn = n->as_Type();
3060 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr();
3061 assert(tinst != NULL && tinst->is_known_instance() &&
3062 tinst->instance_id() == jobj->idx() , "instance type expected.");
3063
3064 const Type *tn_type = igvn->type(tn);
3065 const TypeOopPtr *tn_t;
3066 if (tn_type->isa_narrowoop()) {
3067 tn_t = tn_type->make_ptr()->isa_oopptr();
3068 } else {
3069 tn_t = tn_type->isa_oopptr();
3070 }
3071 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) {
3072 if (tn_type->isa_narrowoop()) {
3073 tn_type = tinst->make_narrowoop();
3074 } else {
3075 tn_type = tinst;
3076 }
3077 igvn->hash_delete(tn);
3078 igvn->set_type(tn, tn_type);
3079 tn->set_type(tn_type);
3080 igvn->hash_insert(tn);
3081 record_for_optimizer(n);
3082 } else {
3083 assert(tn_type == TypePtr::NULL_PTR ||
3084 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()),
3085 "unexpected type");
3086 continue; // Skip dead path with different type
3087 }
3088 }
3089 } else {
3090 debug_only(n->dump();)
3091 assert(false, "EA: unexpected node");
3092 continue;
3093 }
3094 // push allocation's users on appropriate worklist
3095 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3096 Node *use = n->fast_out(i);
3097 if(use->is_Mem() && use->in(MemNode::Address) == n) {
3098 // Load/store to instance's field
3099 memnode_worklist.append_if_missing(use);
3100 } else if (use->is_MemBar()) {
3101 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3102 memnode_worklist.append_if_missing(use);
3103 }
3104 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
3105 Node* addp2 = find_second_addp(use, n);
3106 if (addp2 != NULL) {
3107 alloc_worklist.append_if_missing(addp2);
3108 }
3109 alloc_worklist.append_if_missing(use);
3110 } else if (use->is_Phi() ||
3111 use->is_CheckCastPP() ||
3112 use->is_EncodeNarrowPtr() ||
3113 use->is_DecodeNarrowPtr() ||
3114 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
3115 alloc_worklist.append_if_missing(use);
3116 #ifdef ASSERT
3117 } else if (use->is_Mem()) {
3118 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
3119 } else if (use->is_MergeMem()) {
3120 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3121 } else if (use->is_SafePoint()) {
3122 // Look for MergeMem nodes for calls which reference unique allocation
3123 // (through CheckCastPP nodes) even for debug info.
3124 Node* m = use->in(TypeFunc::Memory);
3125 if (m->is_MergeMem()) {
3126 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3127 }
3128 } else if (use->Opcode() == Op_EncodeISOArray) {
3129 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3130 // EncodeISOArray overwrites destination array
3131 memnode_worklist.append_if_missing(use);
3132 }
3133 } else {
3134 uint op = use->Opcode();
3135 if ((use->in(MemNode::Memory) == n) &&
3136 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) {
3137 // They overwrite memory edge corresponding to destination array,
3138 memnode_worklist.append_if_missing(use);
3139 } else if (!(op == Op_CmpP || op == Op_Conv2B ||
3140 op == Op_CastP2X || op == Op_StoreCM ||
3141 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives ||
3142 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3143 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar ||
3144 op == Op_ValueType)) {
3145 n->dump();
3146 use->dump();
3147 assert(false, "EA: missing allocation reference path");
3148 }
3149 #endif
3150 }
3151 }
3152
3153 }
3154
3155 // Go over all ArrayCopy nodes and if one of the inputs has a unique
3156 // type, record it in the ArrayCopy node so we know what memory this
3157 // node uses/modified.
3158 for (int next = 0; next < arraycopy_worklist.length(); next++) {
3159 ArrayCopyNode* ac = arraycopy_worklist.at(next);
3160 Node* dest = ac->in(ArrayCopyNode::Dest);
3161 if (dest->is_AddP()) {
3162 dest = get_addp_base(dest);
3163 }
3164 JavaObjectNode* jobj = unique_java_object(dest);
3165 if (jobj != NULL) {
3166 Node *base = get_map(jobj->idx());
3167 if (base != NULL) {
3168 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3169 ac->_dest_type = base_t;
3170 }
3171 }
3172 Node* src = ac->in(ArrayCopyNode::Src);
3173 if (src->is_AddP()) {
3174 src = get_addp_base(src);
3175 }
3176 jobj = unique_java_object(src);
3177 if (jobj != NULL) {
3178 Node* base = get_map(jobj->idx());
3179 if (base != NULL) {
3180 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3181 ac->_src_type = base_t;
3182 }
3183 }
3184 }
3185
3186 // New alias types were created in split_AddP().
3187 uint new_index_end = (uint) _compile->num_alias_types();
3188 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1");
3189
3190 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
3191 // compute new values for Memory inputs (the Memory inputs are not
3192 // actually updated until phase 4.)
3193 if (memnode_worklist.length() == 0)
3194 return; // nothing to do
3195 while (memnode_worklist.length() != 0) {
3196 Node *n = memnode_worklist.pop();
3197 if (visited.test_set(n->_idx))
3198 continue;
3199 if (n->is_Phi() || n->is_ClearArray()) {
3200 // we don't need to do anything, but the users must be pushed
3201 } else if (n->is_MemBar()) { // Initialize, MemBar nodes
3202 // we don't need to do anything, but the users must be pushed
3203 n = n->as_MemBar()->proj_out(TypeFunc::Memory);
3204 if (n == NULL)
3205 continue;
3206 } else if (n->Opcode() == Op_StrCompressedCopy ||
3207 n->Opcode() == Op_EncodeISOArray) {
3208 // get the memory projection
3209 n = n->find_out_with(Op_SCMemProj);
3210 assert(n->Opcode() == Op_SCMemProj, "memory projection required");
3211 } else {
3212 assert(n->is_Mem(), "memory node required.");
3213 Node *addr = n->in(MemNode::Address);
3214 const Type *addr_t = igvn->type(addr);
3215 if (addr_t == Type::TOP)
3216 continue;
3217 assert (addr_t->isa_ptr() != NULL, "pointer type required.");
3218 int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
3219 assert ((uint)alias_idx < new_index_end, "wrong alias index");
3220 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis);
3221 if (_compile->failing()) {
3222 return;
3223 }
3224 if (mem != n->in(MemNode::Memory)) {
3225 // We delay the memory edge update since we need old one in
3226 // MergeMem code below when instances memory slices are separated.
3227 set_map(n, mem);
3228 }
3229 if (n->is_Load()) {
3230 continue; // don't push users
3231 } else if (n->is_LoadStore()) {
3232 // get the memory projection
3233 n = n->find_out_with(Op_SCMemProj);
3234 assert(n->Opcode() == Op_SCMemProj, "memory projection required");
3235 }
3236 }
3237 // push user on appropriate worklist
3238 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3239 Node *use = n->fast_out(i);
3240 if (use->is_Phi() || use->is_ClearArray()) {
3241 memnode_worklist.append_if_missing(use);
3242 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) {
3243 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores
3244 continue;
3245 memnode_worklist.append_if_missing(use);
3246 } else if (use->is_MemBar()) {
3247 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3248 memnode_worklist.append_if_missing(use);
3249 }
3250 #ifdef ASSERT
3251 } else if(use->is_Mem()) {
3252 assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
3253 } else if (use->is_MergeMem()) {
3254 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3255 } else if (use->Opcode() == Op_EncodeISOArray) {
3256 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3257 // EncodeISOArray overwrites destination array
3258 memnode_worklist.append_if_missing(use);
3259 }
3260 } else {
3261 uint op = use->Opcode();
3262 if ((use->in(MemNode::Memory) == n) &&
3263 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) {
3264 // They overwrite memory edge corresponding to destination array,
3265 memnode_worklist.append_if_missing(use);
3266 } else if (!(op == Op_StoreCM ||
3267 (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL &&
3268 strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) ||
3269 op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives ||
3270 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3271 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) {
3272 n->dump();
3273 use->dump();
3274 assert(false, "EA: missing memory path");
3275 }
3276 #endif
3277 }
3278 }
3279 }
3280
3281 // Phase 3: Process MergeMem nodes from mergemem_worklist.
3282 // Walk each memory slice moving the first node encountered of each
3283 // instance type to the the input corresponding to its alias index.
3284 uint length = _mergemem_worklist.length();
3285 for( uint next = 0; next < length; ++next ) {
3286 MergeMemNode* nmm = _mergemem_worklist.at(next);
3287 assert(!visited.test_set(nmm->_idx), "should not be visited before");
3288 // Note: we don't want to use MergeMemStream here because we only want to
3289 // scan inputs which exist at the start, not ones we add during processing.
3290 // Note 2: MergeMem may already contains instance memory slices added
3291 // during find_inst_mem() call when memory nodes were processed above.
3292 igvn->hash_delete(nmm);
3293 uint nslices = MIN2(nmm->req(), new_index_start);
3294 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
3295 Node* mem = nmm->in(i);
3296 Node* cur = NULL;
3297 if (mem == NULL || mem->is_top())
3298 continue;
3299 // First, update mergemem by moving memory nodes to corresponding slices
3300 // if their type became more precise since this mergemem was created.
3301 while (mem->is_Mem()) {
3302 const Type *at = igvn->type(mem->in(MemNode::Address));
3303 if (at != Type::TOP) {
3304 assert (at->isa_ptr() != NULL, "pointer type required.");
3305 uint idx = (uint)_compile->get_alias_index(at->is_ptr());
3306 if (idx == i) {
3307 if (cur == NULL)
3308 cur = mem;
3309 } else {
3310 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
3311 nmm->set_memory_at(idx, mem);
3312 }
3313 }
3314 }
3315 mem = mem->in(MemNode::Memory);
3316 }
3317 nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
3318 // Find any instance of the current type if we haven't encountered
3319 // already a memory slice of the instance along the memory chain.
3320 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3321 if((uint)_compile->get_general_index(ni) == i) {
3322 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
3323 if (nmm->is_empty_memory(m)) {
3324 Node* result = find_inst_mem(mem, ni, orig_phis);
3325 if (_compile->failing()) {
3326 return;
3327 }
3328 nmm->set_memory_at(ni, result);
3329 }
3330 }
3331 }
3332 }
3333 // Find the rest of instances values
3334 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3335 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
3336 Node* result = step_through_mergemem(nmm, ni, tinst);
3337 if (result == nmm->base_memory()) {
3338 // Didn't find instance memory, search through general slice recursively.
3339 result = nmm->memory_at(_compile->get_general_index(ni));
3340 result = find_inst_mem(result, ni, orig_phis);
3341 if (_compile->failing()) {
3342 return;
3343 }
3344 nmm->set_memory_at(ni, result);
3345 }
3346 }
3347 igvn->hash_insert(nmm);
3348 record_for_optimizer(nmm);
3349 }
3350
3351 // Phase 4: Update the inputs of non-instance memory Phis and
3352 // the Memory input of memnodes
3353 // First update the inputs of any non-instance Phi's from
3354 // which we split out an instance Phi. Note we don't have
3355 // to recursively process Phi's encounted on the input memory
3356 // chains as is done in split_memory_phi() since they will
3357 // also be processed here.
3358 for (int j = 0; j < orig_phis.length(); j++) {
3359 PhiNode *phi = orig_phis.at(j);
3360 int alias_idx = _compile->get_alias_index(phi->adr_type());
3361 igvn->hash_delete(phi);
3362 for (uint i = 1; i < phi->req(); i++) {
3363 Node *mem = phi->in(i);
3364 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis);
3365 if (_compile->failing()) {
3366 return;
3367 }
3368 if (mem != new_mem) {
3369 phi->set_req(i, new_mem);
3370 }
3371 }
3372 igvn->hash_insert(phi);
3373 record_for_optimizer(phi);
3374 }
3375
3376 // Update the memory inputs of MemNodes with the value we computed
3377 // in Phase 2 and move stores memory users to corresponding memory slices.
3378 // Disable memory split verification code until the fix for 6984348.
3379 // Currently it produces false negative results since it does not cover all cases.
3380 #if 0 // ifdef ASSERT
3381 visited.Reset();
3382 Node_Stack old_mems(arena, _compile->unique() >> 2);
3383 #endif
3384 for (uint i = 0; i < ideal_nodes.size(); i++) {
3385 Node* n = ideal_nodes.at(i);
3386 Node* nmem = get_map(n->_idx);
3387 assert(nmem != NULL, "sanity");
3388 if (n->is_Mem()) {
3389 #if 0 // ifdef ASSERT
3390 Node* old_mem = n->in(MemNode::Memory);
3391 if (!visited.test_set(old_mem->_idx)) {
3392 old_mems.push(old_mem, old_mem->outcnt());
3393 }
3394 #endif
3395 assert(n->in(MemNode::Memory) != nmem, "sanity");
3396 if (!n->is_Load()) {
3397 // Move memory users of a store first.
3398 move_inst_mem(n, orig_phis);
3399 }
3400 // Now update memory input
3401 igvn->hash_delete(n);
3402 n->set_req(MemNode::Memory, nmem);
3403 igvn->hash_insert(n);
3404 record_for_optimizer(n);
3405 } else {
3406 assert(n->is_Allocate() || n->is_CheckCastPP() ||
3407 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()");
3408 }
3409 }
3410 #if 0 // ifdef ASSERT
3411 // Verify that memory was split correctly
3412 while (old_mems.is_nonempty()) {
3413 Node* old_mem = old_mems.node();
3414 uint old_cnt = old_mems.index();
3415 old_mems.pop();
3416 assert(old_cnt == old_mem->outcnt(), "old mem could be lost");
3417 }
3418 #endif
3419 }
3420
3421 #ifndef PRODUCT
3422 static const char *node_type_names[] = {
3423 "UnknownType",
3424 "JavaObject",
3425 "LocalVar",
3426 "Field",
3427 "Arraycopy"
3428 };
3429
3430 static const char *esc_names[] = {
3431 "UnknownEscape",
3432 "NoEscape",
3433 "ArgEscape",
3434 "GlobalEscape"
3435 };
3436
3437 void PointsToNode::dump(bool print_state) const {
3438 NodeType nt = node_type();
3439 tty->print("%s ", node_type_names[(int) nt]);
3440 if (print_state) {
3441 EscapeState es = escape_state();
3442 EscapeState fields_es = fields_escape_state();
3443 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]);
3444 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable())
3445 tty->print("NSR ");
3446 }
3447 if (is_Field()) {
3448 FieldNode* f = (FieldNode*)this;
3449 if (f->is_oop())
3450 tty->print("oop ");
3451 if (f->offset() > 0)
3452 tty->print("+%d ", f->offset());
3453 tty->print("(");
3454 for (BaseIterator i(f); i.has_next(); i.next()) {
3455 PointsToNode* b = i.get();
3456 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : ""));
3457 }
3458 tty->print(" )");
3459 }
3460 tty->print("[");
3461 for (EdgeIterator i(this); i.has_next(); i.next()) {
3462 PointsToNode* e = i.get();
3463 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : "");
3464 }
3465 tty->print(" [");
3466 for (UseIterator i(this); i.has_next(); i.next()) {
3467 PointsToNode* u = i.get();
3468 bool is_base = false;
3469 if (PointsToNode::is_base_use(u)) {
3470 is_base = true;
3471 u = PointsToNode::get_use_node(u)->as_Field();
3472 }
3473 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : "");
3474 }
3475 tty->print(" ]] ");
3476 if (_node == NULL)
3477 tty->print_cr("<null>");
3478 else
3479 _node->dump();
3480 }
3481
3482 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) {
3483 bool first = true;
3484 int ptnodes_length = ptnodes_worklist.length();
3485 for (int i = 0; i < ptnodes_length; i++) {
3486 PointsToNode *ptn = ptnodes_worklist.at(i);
3487 if (ptn == NULL || !ptn->is_JavaObject())
3488 continue;
3489 PointsToNode::EscapeState es = ptn->escape_state();
3490 if ((es != PointsToNode::NoEscape) && !Verbose) {
3491 continue;
3492 }
3493 Node* n = ptn->ideal_node();
3494 if (n->is_Allocate() || (n->is_CallStaticJava() &&
3495 n->as_CallStaticJava()->is_boxing_method())) {
3496 if (first) {
3497 tty->cr();
3498 tty->print("======== Connection graph for ");
3499 _compile->method()->print_short_name();
3500 tty->cr();
3501 first = false;
3502 }
3503 ptn->dump();
3504 // Print all locals and fields which reference this allocation
3505 for (UseIterator j(ptn); j.has_next(); j.next()) {
3506 PointsToNode* use = j.get();
3507 if (use->is_LocalVar()) {
3508 use->dump(Verbose);
3509 } else if (Verbose) {
3510 use->dump();
3511 }
3512 }
3513 tty->cr();
3514 }
3515 }
3516 }
3517 #endif