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