1 /*
2 * Copyright (c) 2005, 2016, 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 "memory/resourceArea.hpp"
31 #include "opto/c2compiler.hpp"
32 #include "opto/arraycopynode.hpp"
33 #include "opto/callnode.hpp"
34 #include "opto/cfgnode.hpp"
35 #include "opto/compile.hpp"
36 #include "opto/escape.hpp"
37 #include "opto/phaseX.hpp"
38 #include "opto/movenode.hpp"
39 #include "opto/rootnode.hpp"
40 #include "opto/valuetypenode.hpp"
41
42 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) :
43 _nodes(C->comp_arena(), C->unique(), C->unique(), NULL),
44 _in_worklist(C->comp_arena()),
45 _next_pidx(0),
46 _collecting(true),
47 _verify(false),
48 _compile(C),
49 _igvn(igvn),
50 _node_map(C->comp_arena()) {
51 // Add unknown java object.
52 add_java_object(C->top(), PointsToNode::GlobalEscape);
53 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject();
54 // Add ConP(#NULL) and ConN(#NULL) nodes.
55 Node* oop_null = igvn->zerocon(T_OBJECT);
56 assert(oop_null->_idx < nodes_size(), "should be created already");
57 add_java_object(oop_null, PointsToNode::NoEscape);
58 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject();
59 if (UseCompressedOops) {
60 Node* noop_null = igvn->zerocon(T_NARROWOOP);
61 assert(noop_null->_idx < nodes_size(), "should be created already");
62 map_ideal_node(noop_null, null_obj);
63 }
64 _pcmp_neq = NULL; // Should be initialized
65 _pcmp_eq = NULL;
66 }
67
68 bool ConnectionGraph::has_candidates(Compile *C) {
69 // EA brings benefits only when the code has allocations and/or locks which
70 // are represented by ideal Macro nodes.
71 int cnt = C->macro_count();
72 for (int i = 0; i < cnt; i++) {
73 Node *n = C->macro_node(i);
74 if (n->is_Allocate())
75 return true;
76 if (n->is_Lock()) {
77 Node* obj = n->as_Lock()->obj_node()->uncast();
78 if (!(obj->is_Parm() || obj->is_Con()))
79 return true;
80 }
81 if (n->is_CallStaticJava() &&
82 n->as_CallStaticJava()->is_boxing_method()) {
83 return true;
84 }
85 }
86 return false;
87 }
88
89 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
90 Compile::TracePhase tp("escapeAnalysis", &Phase::timers[Phase::_t_escapeAnalysis]);
91 ResourceMark rm;
92
93 // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction
94 // to create space for them in ConnectionGraph::_nodes[].
95 Node* oop_null = igvn->zerocon(T_OBJECT);
96 Node* noop_null = igvn->zerocon(T_NARROWOOP);
97 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn);
98 // Perform escape analysis
99 if (congraph->compute_escape()) {
100 // There are non escaping objects.
101 C->set_congraph(congraph);
102 }
103 // Cleanup.
104 if (oop_null->outcnt() == 0)
105 igvn->hash_delete(oop_null);
106 if (noop_null->outcnt() == 0)
107 igvn->hash_delete(noop_null);
108 }
109
110 bool ConnectionGraph::compute_escape() {
111 Compile* C = _compile;
112 PhaseGVN* igvn = _igvn;
113
114 // Worklists used by EA.
115 Unique_Node_List delayed_worklist;
116 GrowableArray<Node*> alloc_worklist;
117 GrowableArray<Node*> ptr_cmp_worklist;
118 GrowableArray<Node*> storestore_worklist;
119 GrowableArray<ArrayCopyNode*> arraycopy_worklist;
120 GrowableArray<PointsToNode*> ptnodes_worklist;
121 GrowableArray<JavaObjectNode*> java_objects_worklist;
122 GrowableArray<JavaObjectNode*> non_escaped_worklist;
123 GrowableArray<FieldNode*> oop_fields_worklist;
124 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; )
125
126 { Compile::TracePhase tp("connectionGraph", &Phase::timers[Phase::_t_connectionGraph]);
127
128 // 1. Populate Connection Graph (CG) with PointsTo nodes.
129 ideal_nodes.map(C->live_nodes(), NULL); // preallocate space
130 // Initialize worklist
131 if (C->root() != NULL) {
132 ideal_nodes.push(C->root());
133 }
134 // Processed ideal nodes are unique on ideal_nodes list
135 // but several ideal nodes are mapped to the phantom_obj.
136 // To avoid duplicated entries on the following worklists
137 // add the phantom_obj only once to them.
138 ptnodes_worklist.append(phantom_obj);
139 java_objects_worklist.append(phantom_obj);
140 for( uint next = 0; next < ideal_nodes.size(); ++next ) {
141 Node* n = ideal_nodes.at(next);
142 // Create PointsTo nodes and add them to Connection Graph. Called
143 // only once per ideal node since ideal_nodes is Unique_Node list.
144 add_node_to_connection_graph(n, &delayed_worklist);
145 PointsToNode* ptn = ptnode_adr(n->_idx);
146 if (ptn != NULL && ptn != phantom_obj) {
147 ptnodes_worklist.append(ptn);
148 if (ptn->is_JavaObject()) {
149 java_objects_worklist.append(ptn->as_JavaObject());
150 if ((n->is_Allocate() || n->is_CallStaticJava()) &&
151 (ptn->escape_state() < PointsToNode::GlobalEscape)) {
152 // Only allocations and java static calls results are interesting.
153 non_escaped_worklist.append(ptn->as_JavaObject());
154 }
155 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) {
156 oop_fields_worklist.append(ptn->as_Field());
157 }
158 }
159 if (n->is_MergeMem()) {
160 // Collect all MergeMem nodes to add memory slices for
161 // scalar replaceable objects in split_unique_types().
162 _mergemem_worklist.append(n->as_MergeMem());
163 } else if (OptimizePtrCompare && n->is_Cmp() &&
164 (n->Opcode() == Op_CmpP || n->Opcode() == Op_CmpN)) {
165 // Collect compare pointers nodes.
166 ptr_cmp_worklist.append(n);
167 } else if (n->is_MemBarStoreStore()) {
168 // Collect all MemBarStoreStore nodes so that depending on the
169 // escape status of the associated Allocate node some of them
170 // may be eliminated.
171 storestore_worklist.append(n);
172 } else if (n->is_MemBar() && (n->Opcode() == Op_MemBarRelease) &&
173 (n->req() > MemBarNode::Precedent)) {
174 record_for_optimizer(n);
175 #ifdef ASSERT
176 } else if (n->is_AddP()) {
177 // Collect address nodes for graph verification.
178 addp_worklist.append(n);
179 #endif
180 } else if (n->is_ArrayCopy()) {
181 // Keep a list of ArrayCopy nodes so if one of its input is non
182 // escaping, we can record a unique type
183 arraycopy_worklist.append(n->as_ArrayCopy());
184 }
185 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
186 Node* m = n->fast_out(i); // Get user
187 ideal_nodes.push(m);
188 }
189 }
190 if (non_escaped_worklist.length() == 0) {
191 _collecting = false;
192 return false; // Nothing to do.
193 }
194 // Add final simple edges to graph.
195 while(delayed_worklist.size() > 0) {
196 Node* n = delayed_worklist.pop();
197 add_final_edges(n);
198 }
199 int ptnodes_length = ptnodes_worklist.length();
200
201 #ifdef ASSERT
202 if (VerifyConnectionGraph) {
203 // Verify that no new simple edges could be created and all
204 // local vars has edges.
205 _verify = true;
206 for (int next = 0; next < ptnodes_length; ++next) {
207 PointsToNode* ptn = ptnodes_worklist.at(next);
208 add_final_edges(ptn->ideal_node());
209 if (ptn->is_LocalVar() && ptn->edge_count() == 0) {
210 ptn->dump();
211 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity");
212 }
213 }
214 _verify = false;
215 }
216 #endif
217 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes
218 // processing, calls to CI to resolve symbols (types, fields, methods)
219 // referenced in bytecode. During symbol resolution VM may throw
220 // an exception which CI cleans and converts to compilation failure.
221 if (C->failing()) return false;
222
223 // 2. Finish Graph construction by propagating references to all
224 // java objects through graph.
225 if (!complete_connection_graph(ptnodes_worklist, non_escaped_worklist,
226 java_objects_worklist, oop_fields_worklist)) {
227 // All objects escaped or hit time or iterations limits.
228 _collecting = false;
229 return false;
230 }
231
232 // 3. Adjust scalar_replaceable state of nonescaping objects and push
233 // scalar replaceable allocations on alloc_worklist for processing
234 // in split_unique_types().
235 int non_escaped_length = non_escaped_worklist.length();
236 for (int next = 0; next < non_escaped_length; next++) {
237 JavaObjectNode* ptn = non_escaped_worklist.at(next);
238 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape);
239 Node* n = ptn->ideal_node();
240 if (n->is_Allocate()) {
241 n->as_Allocate()->_is_non_escaping = noescape;
242 }
243 if (n->is_CallStaticJava()) {
244 n->as_CallStaticJava()->_is_non_escaping = noescape;
245 }
246 if (noescape && ptn->scalar_replaceable()) {
247 adjust_scalar_replaceable_state(ptn);
248 if (ptn->scalar_replaceable()) {
249 alloc_worklist.append(ptn->ideal_node());
250 }
251 }
252 }
253
254 #ifdef ASSERT
255 if (VerifyConnectionGraph) {
256 // Verify that graph is complete - no new edges could be added or needed.
257 verify_connection_graph(ptnodes_worklist, non_escaped_worklist,
258 java_objects_worklist, addp_worklist);
259 }
260 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build");
261 assert(null_obj->escape_state() == PointsToNode::NoEscape &&
262 null_obj->edge_count() == 0 &&
263 !null_obj->arraycopy_src() &&
264 !null_obj->arraycopy_dst(), "sanity");
265 #endif
266
267 _collecting = false;
268
269 } // TracePhase t3("connectionGraph")
270
271 // 4. Optimize ideal graph based on EA information.
272 bool has_non_escaping_obj = (non_escaped_worklist.length() > 0);
273 if (has_non_escaping_obj) {
274 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist);
275 }
276
277 #ifndef PRODUCT
278 if (PrintEscapeAnalysis) {
279 dump(ptnodes_worklist); // Dump ConnectionGraph
280 }
281 #endif
282
283 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0);
284 #ifdef ASSERT
285 if (VerifyConnectionGraph) {
286 int alloc_length = alloc_worklist.length();
287 for (int next = 0; next < alloc_length; ++next) {
288 Node* n = alloc_worklist.at(next);
289 PointsToNode* ptn = ptnode_adr(n->_idx);
290 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity");
291 }
292 }
293 #endif
294
295 // 5. Separate memory graph for scalar replaceable allcations.
296 if (has_scalar_replaceable_candidates &&
297 C->AliasLevel() >= 3 && EliminateAllocations) {
298 // Now use the escape information to create unique types for
299 // scalar replaceable objects.
300 split_unique_types(alloc_worklist, arraycopy_worklist);
301 if (C->failing()) return false;
302 C->print_method(PHASE_AFTER_EA, 2);
303
304 #ifdef ASSERT
305 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
306 tty->print("=== No allocations eliminated for ");
307 C->method()->print_short_name();
308 if(!EliminateAllocations) {
309 tty->print(" since EliminateAllocations is off ===");
310 } else if(!has_scalar_replaceable_candidates) {
311 tty->print(" since there are no scalar replaceable candidates ===");
312 } else if(C->AliasLevel() < 3) {
313 tty->print(" since AliasLevel < 3 ===");
314 }
315 tty->cr();
316 #endif
317 }
318 return has_non_escaping_obj;
319 }
320
321 // Utility function for nodes that load an object
322 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
323 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
324 // ThreadLocal has RawPtr type.
325 const Type* t = _igvn->type(n);
326 if (t->make_ptr() != NULL) {
327 Node* adr = n->in(MemNode::Address);
328 #ifdef ASSERT
329 if (!adr->is_AddP()) {
330 assert(_igvn->type(adr)->isa_rawptr(), "sanity");
331 } else {
332 assert((ptnode_adr(adr->_idx) == NULL ||
333 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity");
334 }
335 #endif
336 add_local_var_and_edge(n, PointsToNode::NoEscape,
337 adr, delayed_worklist);
338 }
339 }
340
341 // Populate Connection Graph with PointsTo nodes and create simple
342 // connection graph edges.
343 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
344 assert(!_verify, "this method should not be called for verification");
345 PhaseGVN* igvn = _igvn;
346 uint n_idx = n->_idx;
347 PointsToNode* n_ptn = ptnode_adr(n_idx);
348 if (n_ptn != NULL)
349 return; // No need to redefine PointsTo node during first iteration.
350
351 if (n->is_Call()) {
352 // Arguments to allocation and locking don't escape.
353 if (n->is_AbstractLock()) {
354 // Put Lock and Unlock nodes on IGVN worklist to process them during
355 // first IGVN optimization when escape information is still available.
356 record_for_optimizer(n);
357 } else if (n->is_Allocate()) {
358 add_call_node(n->as_Call());
359 record_for_optimizer(n);
360 } else {
361 if (n->is_CallStaticJava()) {
362 const char* name = n->as_CallStaticJava()->_name;
363 if (name != NULL && strcmp(name, "uncommon_trap") == 0)
364 return; // Skip uncommon traps
365 }
366 // Don't mark as processed since call's arguments have to be processed.
367 delayed_worklist->push(n);
368 // Check if a call returns an object.
369 if ((n->as_Call()->returns_pointer() &&
370 n->as_Call()->proj_out(TypeFunc::Parms) != NULL) ||
371 (n->is_CallStaticJava() &&
372 n->as_CallStaticJava()->is_boxing_method())) {
373 add_call_node(n->as_Call());
374 } else if (n->as_Call()->tf()->returns_value_type_as_fields()) {
375 bool returns_oop = false;
376 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax && !returns_oop; i++) {
377 ProjNode* pn = n->fast_out(i)->as_Proj();
378 if (pn->_con >= TypeFunc::Parms && pn->bottom_type()->isa_oopptr()) {
379 returns_oop = true;
380 }
381 }
382 if (returns_oop) {
383 add_call_node(n->as_Call());
384 }
385 }
386 }
387 return;
388 }
389 // Put this check here to process call arguments since some call nodes
390 // point to phantom_obj.
391 if (n_ptn == phantom_obj || n_ptn == null_obj)
392 return; // Skip predefined nodes.
393
394 int opcode = n->Opcode();
395 switch (opcode) {
396 case Op_AddP: {
397 Node* base = get_addp_base(n);
398 PointsToNode* ptn_base = ptnode_adr(base->_idx);
399 // Field nodes are created for all field types. They are used in
400 // adjust_scalar_replaceable_state() and split_unique_types().
401 // Note, non-oop fields will have only base edges in Connection
402 // Graph because such fields are not used for oop loads and stores.
403 int offset = address_offset(n, igvn);
404 add_field(n, PointsToNode::NoEscape, offset);
405 if (ptn_base == NULL) {
406 delayed_worklist->push(n); // Process it later.
407 } else {
408 n_ptn = ptnode_adr(n_idx);
409 add_base(n_ptn->as_Field(), ptn_base);
410 }
411 break;
412 }
413 case Op_CastX2P: {
414 map_ideal_node(n, phantom_obj);
415 break;
416 }
417 case Op_CastPP:
418 case Op_CheckCastPP:
419 case Op_EncodeP:
420 case Op_DecodeN:
421 case Op_EncodePKlass:
422 case Op_DecodeNKlass: {
423 add_local_var_and_edge(n, PointsToNode::NoEscape,
424 n->in(1), delayed_worklist);
425 break;
426 }
427 case Op_CMoveP: {
428 add_local_var(n, PointsToNode::NoEscape);
429 // Do not add edges during first iteration because some could be
430 // not defined yet.
431 delayed_worklist->push(n);
432 break;
433 }
434 case Op_ConP:
435 case Op_ConN:
436 case Op_ConNKlass: {
437 // assume all oop constants globally escape except for null
438 PointsToNode::EscapeState es;
439 const Type* t = igvn->type(n);
440 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) {
441 es = PointsToNode::NoEscape;
442 } else {
443 es = PointsToNode::GlobalEscape;
444 }
445 add_java_object(n, es);
446 break;
447 }
448 case Op_CreateEx: {
449 // assume that all exception objects globally escape
450 map_ideal_node(n, phantom_obj);
451 break;
452 }
453 case Op_LoadKlass:
454 case Op_LoadNKlass: {
455 // Unknown class is loaded
456 map_ideal_node(n, phantom_obj);
457 break;
458 }
459 case Op_LoadP:
460 case Op_LoadN:
461 case Op_LoadPLocked: {
462 add_objload_to_connection_graph(n, delayed_worklist);
463 break;
464 }
465 case Op_Parm: {
466 map_ideal_node(n, phantom_obj);
467 break;
468 }
469 case Op_PartialSubtypeCheck: {
470 // Produces Null or notNull and is used in only in CmpP so
471 // phantom_obj could be used.
472 map_ideal_node(n, phantom_obj); // Result is unknown
473 break;
474 }
475 case Op_Phi: {
476 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
477 // ThreadLocal has RawPtr type.
478 const Type* t = n->as_Phi()->type();
479 if (t->make_ptr() != NULL) {
480 add_local_var(n, PointsToNode::NoEscape);
481 // Do not add edges during first iteration because some could be
482 // not defined yet.
483 delayed_worklist->push(n);
484 }
485 break;
486 }
487 case Op_Proj: {
488 // we are only interested in the oop result projection from a call
489 if (n->as_Proj()->_con >= TypeFunc::Parms && n->in(0)->is_Call() &&
490 (n->in(0)->as_Call()->returns_pointer() || n->bottom_type()->isa_oopptr())) {
491 assert((n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->as_Call()->returns_pointer()) ||
492 n->in(0)->as_Call()->tf()->returns_value_type_as_fields(), "what kind of oop return is it?");
493 add_local_var_and_edge(n, PointsToNode::NoEscape,
494 n->in(0), delayed_worklist);
495 }
496 break;
497 }
498 case Op_Rethrow: // Exception object escapes
499 case Op_Return: {
500 if (n->req() > TypeFunc::Parms &&
501 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
502 // Treat Return value as LocalVar with GlobalEscape escape state.
503 add_local_var_and_edge(n, PointsToNode::GlobalEscape,
504 n->in(TypeFunc::Parms), delayed_worklist);
505 }
506 break;
507 }
508 case Op_CompareAndExchangeP:
509 case Op_CompareAndExchangeN:
510 case Op_GetAndSetP:
511 case Op_GetAndSetN: {
512 add_objload_to_connection_graph(n, delayed_worklist);
513 // fallthrough
514 }
515 case Op_StoreP:
516 case Op_StoreN:
517 case Op_StoreNKlass:
518 case Op_StorePConditional:
519 case Op_WeakCompareAndSwapP:
520 case Op_WeakCompareAndSwapN:
521 case Op_CompareAndSwapP:
522 case Op_CompareAndSwapN: {
523 Node* adr = n->in(MemNode::Address);
524 const Type *adr_type = igvn->type(adr);
525 adr_type = adr_type->make_ptr();
526 if (adr_type == NULL) {
527 break; // skip dead nodes
528 }
529 if (adr_type->isa_oopptr() ||
530 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) &&
531 (adr_type == TypeRawPtr::NOTNULL &&
532 adr->in(AddPNode::Address)->is_Proj() &&
533 adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
534 delayed_worklist->push(n); // Process it later.
535 #ifdef ASSERT
536 assert(adr->is_AddP(), "expecting an AddP");
537 if (adr_type == TypeRawPtr::NOTNULL) {
538 // Verify a raw address for a store captured by Initialize node.
539 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
540 assert(offs != Type::OffsetBot, "offset must be a constant");
541 }
542 #endif
543 } else {
544 // Ignore copy the displaced header to the BoxNode (OSR compilation).
545 if (adr->is_BoxLock())
546 break;
547 // Stored value escapes in unsafe access.
548 if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
549 // Pointer stores in G1 barriers looks like unsafe access.
550 // Ignore such stores to be able scalar replace non-escaping
551 // allocations.
552 if (UseG1GC && adr->is_AddP()) {
553 Node* base = get_addp_base(adr);
554 if (base->Opcode() == Op_LoadP &&
555 base->in(MemNode::Address)->is_AddP()) {
556 adr = base->in(MemNode::Address);
557 Node* tls = get_addp_base(adr);
558 if (tls->Opcode() == Op_ThreadLocal) {
559 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
560 if (offs == in_bytes(JavaThread::satb_mark_queue_offset() +
561 SATBMarkQueue::byte_offset_of_buf())) {
562 break; // G1 pre barrier previous oop value store.
563 }
564 if (offs == in_bytes(JavaThread::dirty_card_queue_offset() +
565 DirtyCardQueue::byte_offset_of_buf())) {
566 break; // G1 post barrier card address store.
567 }
568 }
569 }
570 }
571 delayed_worklist->push(n); // Process unsafe access later.
572 break;
573 }
574 #ifdef ASSERT
575 n->dump(1);
576 assert(false, "not unsafe or G1 barrier raw StoreP");
577 #endif
578 }
579 break;
580 }
581 case Op_AryEq:
582 case Op_HasNegatives:
583 case Op_StrComp:
584 case Op_StrEquals:
585 case Op_StrIndexOf:
586 case Op_StrIndexOfChar:
587 case Op_StrInflatedCopy:
588 case Op_StrCompressedCopy:
589 case Op_EncodeISOArray: {
590 add_local_var(n, PointsToNode::ArgEscape);
591 delayed_worklist->push(n); // Process it later.
592 break;
593 }
594 case Op_ThreadLocal: {
595 add_java_object(n, PointsToNode::ArgEscape);
596 break;
597 }
598 case Op_ValueTypePtr: {
599 add_local_var_and_edge(n, PointsToNode::NoEscape,
600 n->as_ValueTypeBase()->get_oop(), delayed_worklist);
601 break;
602 }
603 default:
604 ; // Do nothing for nodes not related to EA.
605 }
606 return;
607 }
608
609 #ifdef ASSERT
610 #define ELSE_FAIL(name) \
611 /* Should not be called for not pointer type. */ \
612 n->dump(1); \
613 assert(false, name); \
614 break;
615 #else
616 #define ELSE_FAIL(name) \
617 break;
618 #endif
619
620 // Add final simple edges to graph.
621 void ConnectionGraph::add_final_edges(Node *n) {
622 PointsToNode* n_ptn = ptnode_adr(n->_idx);
623 #ifdef ASSERT
624 if (_verify && n_ptn->is_JavaObject())
625 return; // This method does not change graph for JavaObject.
626 #endif
627
628 if (n->is_Call()) {
629 process_call_arguments(n->as_Call());
630 return;
631 }
632 assert(n->is_Store() || n->is_LoadStore() ||
633 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL),
634 "node should be registered already");
635 int opcode = n->Opcode();
636 switch (opcode) {
637 case Op_AddP: {
638 Node* base = get_addp_base(n);
639 PointsToNode* ptn_base = ptnode_adr(base->_idx);
640 assert(ptn_base != NULL, "field's base should be registered");
641 add_base(n_ptn->as_Field(), ptn_base);
642 break;
643 }
644 case Op_CastPP:
645 case Op_CheckCastPP:
646 case Op_EncodeP:
647 case Op_DecodeN:
648 case Op_EncodePKlass:
649 case Op_DecodeNKlass: {
650 add_local_var_and_edge(n, PointsToNode::NoEscape,
651 n->in(1), NULL);
652 break;
653 }
654 case Op_CMoveP: {
655 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) {
656 Node* in = n->in(i);
657 if (in == NULL)
658 continue; // ignore NULL
659 Node* uncast_in = in->uncast();
660 if (uncast_in->is_top() || uncast_in == n)
661 continue; // ignore top or inputs which go back this node
662 PointsToNode* ptn = ptnode_adr(in->_idx);
663 assert(ptn != NULL, "node should be registered");
664 add_edge(n_ptn, ptn);
665 }
666 break;
667 }
668 case Op_LoadP:
669 case Op_LoadN:
670 case Op_LoadPLocked: {
671 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
672 // ThreadLocal has RawPtr type.
673 const Type* t = _igvn->type(n);
674 if (t->make_ptr() != NULL) {
675 Node* adr = n->in(MemNode::Address);
676 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
677 break;
678 }
679 ELSE_FAIL("Op_LoadP");
680 }
681 case Op_Phi: {
682 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
683 // ThreadLocal has RawPtr type.
684 const Type* t = n->as_Phi()->type();
685 if (t->make_ptr() != NULL) {
686 for (uint i = 1; i < n->req(); i++) {
687 Node* in = n->in(i);
688 if (in == NULL)
689 continue; // ignore NULL
690 Node* uncast_in = in->uncast();
691 if (uncast_in->is_top() || uncast_in == n)
692 continue; // ignore top or inputs which go back this node
693 PointsToNode* ptn = ptnode_adr(in->_idx);
694 assert(ptn != NULL, "node should be registered");
695 add_edge(n_ptn, ptn);
696 }
697 break;
698 }
699 ELSE_FAIL("Op_Phi");
700 }
701 case Op_Proj: {
702 // we are only interested in the oop result projection from a call
703 if (n->as_Proj()->_con >= TypeFunc::Parms && n->in(0)->is_Call() &&
704 (n->in(0)->as_Call()->returns_pointer()|| n->bottom_type()->isa_oopptr())) {
705 assert((n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->as_Call()->returns_pointer()) ||
706 n->in(0)->as_Call()->tf()->returns_value_type_as_fields(), "what kind of oop return is it?");
707 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL);
708 break;
709 }
710 ELSE_FAIL("Op_Proj");
711 }
712 case Op_Rethrow: // Exception object escapes
713 case Op_Return: {
714 if (n->req() > TypeFunc::Parms &&
715 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
716 // Treat Return value as LocalVar with GlobalEscape escape state.
717 add_local_var_and_edge(n, PointsToNode::GlobalEscape,
718 n->in(TypeFunc::Parms), NULL);
719 break;
720 }
721 ELSE_FAIL("Op_Return");
722 }
723 case Op_StoreP:
724 case Op_StoreN:
725 case Op_StoreNKlass:
726 case Op_StorePConditional:
727 case Op_CompareAndExchangeP:
728 case Op_CompareAndExchangeN:
729 case Op_CompareAndSwapP:
730 case Op_CompareAndSwapN:
731 case Op_WeakCompareAndSwapP:
732 case Op_WeakCompareAndSwapN:
733 case Op_GetAndSetP:
734 case Op_GetAndSetN: {
735 Node* adr = n->in(MemNode::Address);
736 const Type *adr_type = _igvn->type(adr);
737 adr_type = adr_type->make_ptr();
738 #ifdef ASSERT
739 if (adr_type == NULL) {
740 n->dump(1);
741 assert(adr_type != NULL, "dead node should not be on list");
742 break;
743 }
744 #endif
745 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN ||
746 opcode == Op_CompareAndExchangeN || opcode == Op_CompareAndExchangeP) {
747 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
748 }
749 if (adr_type->isa_oopptr() ||
750 (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass) &&
751 (adr_type == TypeRawPtr::NOTNULL &&
752 adr->in(AddPNode::Address)->is_Proj() &&
753 adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
754 // Point Address to Value
755 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
756 assert(adr_ptn != NULL &&
757 adr_ptn->as_Field()->is_oop(), "node should be registered");
758 Node *val = n->in(MemNode::ValueIn);
759 PointsToNode* ptn = ptnode_adr(val->_idx);
760 assert(ptn != NULL, "node should be registered");
761 add_edge(adr_ptn, ptn);
762 break;
763 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
764 // Stored value escapes in unsafe access.
765 Node *val = n->in(MemNode::ValueIn);
766 PointsToNode* ptn = ptnode_adr(val->_idx);
767 assert(ptn != NULL, "node should be registered");
768 set_escape_state(ptn, PointsToNode::GlobalEscape);
769 // Add edge to object for unsafe access with offset.
770 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
771 assert(adr_ptn != NULL, "node should be registered");
772 if (adr_ptn->is_Field()) {
773 assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
774 add_edge(adr_ptn, ptn);
775 }
776 break;
777 }
778 ELSE_FAIL("Op_StoreP");
779 }
780 case Op_AryEq:
781 case Op_HasNegatives:
782 case Op_StrComp:
783 case Op_StrEquals:
784 case Op_StrIndexOf:
785 case Op_StrIndexOfChar:
786 case Op_StrInflatedCopy:
787 case Op_StrCompressedCopy:
788 case Op_EncodeISOArray: {
789 // char[]/byte[] arrays passed to string intrinsic do not escape but
790 // they are not scalar replaceable. Adjust escape state for them.
791 // Start from in(2) edge since in(1) is memory edge.
792 for (uint i = 2; i < n->req(); i++) {
793 Node* adr = n->in(i);
794 const Type* at = _igvn->type(adr);
795 if (!adr->is_top() && at->isa_ptr()) {
796 assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
797 at->isa_ptr() != NULL, "expecting a pointer");
798 if (adr->is_AddP()) {
799 adr = get_addp_base(adr);
800 }
801 PointsToNode* ptn = ptnode_adr(adr->_idx);
802 assert(ptn != NULL, "node should be registered");
803 add_edge(n_ptn, ptn);
804 }
805 }
806 break;
807 }
808 case Op_ValueTypePtr: {
809 add_local_var_and_edge(n, PointsToNode::NoEscape,
810 n->as_ValueTypeBase()->get_oop(), NULL);
811 break;
812 }
813 default: {
814 // This method should be called only for EA specific nodes which may
815 // miss some edges when they were created.
816 #ifdef ASSERT
817 n->dump(1);
818 #endif
819 guarantee(false, "unknown node");
820 }
821 }
822 return;
823 }
824
825 void ConnectionGraph::add_call_node(CallNode* call) {
826 assert(call->returns_pointer() || call->tf()->returns_value_type_as_fields(), "only for call which returns pointer");
827 uint call_idx = call->_idx;
828 if (call->is_Allocate()) {
829 Node* k = call->in(AllocateNode::KlassNode);
830 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr();
831 assert(kt != NULL, "TypeKlassPtr required.");
832 ciKlass* cik = kt->klass();
833 PointsToNode::EscapeState es = PointsToNode::NoEscape;
834 bool scalar_replaceable = true;
835 if (call->is_AllocateArray()) {
836 if (!cik->is_array_klass()) { // StressReflectiveCode
837 es = PointsToNode::GlobalEscape;
838 } else {
839 int length = call->in(AllocateNode::ALength)->find_int_con(-1);
840 if (length < 0 || length > EliminateAllocationArraySizeLimit) {
841 // Not scalar replaceable if the length is not constant or too big.
842 scalar_replaceable = false;
843 }
844 }
845 } else { // Allocate instance
846 if (cik->is_subclass_of(_compile->env()->Thread_klass()) ||
847 cik->is_subclass_of(_compile->env()->Reference_klass()) ||
848 !cik->is_instance_klass() || // StressReflectiveCode
849 !cik->as_instance_klass()->can_be_instantiated() ||
850 cik->as_instance_klass()->has_finalizer()) {
851 es = PointsToNode::GlobalEscape;
852 }
853 }
854 add_java_object(call, es);
855 PointsToNode* ptn = ptnode_adr(call_idx);
856 if (!scalar_replaceable && ptn->scalar_replaceable()) {
857 ptn->set_scalar_replaceable(false);
858 }
859 } else if (call->is_CallStaticJava()) {
860 // Call nodes could be different types:
861 //
862 // 1. CallDynamicJavaNode (what happened during call is unknown):
863 //
864 // - mapped to GlobalEscape JavaObject node if oop is returned;
865 //
866 // - all oop arguments are escaping globally;
867 //
868 // 2. CallStaticJavaNode (execute bytecode analysis if possible):
869 //
870 // - the same as CallDynamicJavaNode if can't do bytecode analysis;
871 //
872 // - mapped to GlobalEscape JavaObject node if unknown oop is returned;
873 // - mapped to NoEscape JavaObject node if non-escaping object allocated
874 // during call is returned;
875 // - mapped to ArgEscape LocalVar node pointed to object arguments
876 // which are returned and does not escape during call;
877 //
878 // - oop arguments escaping status is defined by bytecode analysis;
879 //
880 // For a static call, we know exactly what method is being called.
881 // Use bytecode estimator to record whether the call's return value escapes.
882 ciMethod* meth = call->as_CallJava()->method();
883 if (meth == NULL) {
884 const char* name = call->as_CallStaticJava()->_name;
885 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check");
886 // Returns a newly allocated unescaped object.
887 add_java_object(call, PointsToNode::NoEscape);
888 ptnode_adr(call_idx)->set_scalar_replaceable(false);
889 } else if (meth->is_boxing_method()) {
890 // Returns boxing object
891 PointsToNode::EscapeState es;
892 vmIntrinsics::ID intr = meth->intrinsic_id();
893 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) {
894 // It does not escape if object is always allocated.
895 es = PointsToNode::NoEscape;
896 } else {
897 // It escapes globally if object could be loaded from cache.
898 es = PointsToNode::GlobalEscape;
899 }
900 add_java_object(call, es);
901 } else {
902 BCEscapeAnalyzer* call_analyzer = meth->get_bcea();
903 call_analyzer->copy_dependencies(_compile->dependencies());
904 if (call_analyzer->is_return_allocated()) {
905 // Returns a newly allocated unescaped object, simply
906 // update dependency information.
907 // Mark it as NoEscape so that objects referenced by
908 // it's fields will be marked as NoEscape at least.
909 add_java_object(call, PointsToNode::NoEscape);
910 ptnode_adr(call_idx)->set_scalar_replaceable(false);
911 } else {
912 // Determine whether any arguments are returned.
913 const TypeTuple* d = call->tf()->domain_cc();
914 bool ret_arg = false;
915 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
916 if (d->field_at(i)->isa_ptr() != NULL &&
917 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
918 ret_arg = true;
919 break;
920 }
921 }
922 if (ret_arg) {
923 add_local_var(call, PointsToNode::ArgEscape);
924 } else {
925 // Returns unknown object.
926 map_ideal_node(call, phantom_obj);
927 }
928 }
929 }
930 } else {
931 // An other type of call, assume the worst case:
932 // returned value is unknown and globally escapes.
933 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check");
934 map_ideal_node(call, phantom_obj);
935 }
936 }
937
938 void ConnectionGraph::process_call_arguments(CallNode *call) {
939 bool is_arraycopy = false;
940 switch (call->Opcode()) {
941 #ifdef ASSERT
942 case Op_Allocate:
943 case Op_AllocateArray:
944 case Op_Lock:
945 case Op_Unlock:
946 assert(false, "should be done already");
947 break;
948 #endif
949 case Op_ArrayCopy:
950 case Op_CallLeafNoFP:
951 // Most array copies are ArrayCopy nodes at this point but there
952 // are still a few direct calls to the copy subroutines (See
953 // PhaseStringOpts::copy_string())
954 is_arraycopy = (call->Opcode() == Op_ArrayCopy) ||
955 call->as_CallLeaf()->is_call_to_arraycopystub();
956 // fall through
957 case Op_CallLeaf: {
958 // Stub calls, objects do not escape but they are not scale replaceable.
959 // Adjust escape state for outgoing arguments.
960 const TypeTuple * d = call->tf()->domain_sig();
961 bool src_has_oops = false;
962 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
963 const Type* at = d->field_at(i);
964 Node *arg = call->in(i);
965 if (arg == NULL) {
966 continue;
967 }
968 const Type *aat = _igvn->type(arg);
969 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr())
970 continue;
971 if (arg->is_AddP()) {
972 //
973 // The inline_native_clone() case when the arraycopy stub is called
974 // after the allocation before Initialize and CheckCastPP nodes.
975 // Or normal arraycopy for object arrays case.
976 //
977 // Set AddP's base (Allocate) as not scalar replaceable since
978 // pointer to the base (with offset) is passed as argument.
979 //
980 arg = get_addp_base(arg);
981 }
982 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
983 assert(arg_ptn != NULL, "should be registered");
984 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state();
985 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) {
986 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
987 aat->isa_ptr() != NULL, "expecting an Ptr");
988 bool arg_has_oops = aat->isa_oopptr() &&
989 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() ||
990 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass()));
991 if (i == TypeFunc::Parms) {
992 src_has_oops = arg_has_oops;
993 }
994 //
995 // src or dst could be j.l.Object when other is basic type array:
996 //
997 // arraycopy(char[],0,Object*,0,size);
998 // arraycopy(Object*,0,char[],0,size);
999 //
1000 // Don't add edges in such cases.
1001 //
1002 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy &&
1003 arg_has_oops && (i > TypeFunc::Parms);
1004 #ifdef ASSERT
1005 if (!(is_arraycopy ||
1006 (call->as_CallLeaf()->_name != NULL &&
1007 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre") == 0 ||
1008 strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 ||
1009 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 ||
1010 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 ||
1011 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 ||
1012 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 ||
1013 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 ||
1014 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 ||
1015 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 ||
1016 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 ||
1017 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 ||
1018 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 ||
1019 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 ||
1020 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 ||
1021 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 ||
1022 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 ||
1023 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 ||
1024 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 ||
1025 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 ||
1026 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 ||
1027 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 ||
1028 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 ||
1029 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0)
1030 ))) {
1031 call->dump();
1032 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name);
1033 }
1034 #endif
1035 // Always process arraycopy's destination object since
1036 // we need to add all possible edges to references in
1037 // source object.
1038 if (arg_esc >= PointsToNode::ArgEscape &&
1039 !arg_is_arraycopy_dest) {
1040 continue;
1041 }
1042 PointsToNode::EscapeState es = PointsToNode::ArgEscape;
1043 if (call->is_ArrayCopy()) {
1044 ArrayCopyNode* ac = call->as_ArrayCopy();
1045 if (ac->is_clonebasic() ||
1046 ac->is_arraycopy_validated() ||
1047 ac->is_copyof_validated() ||
1048 ac->is_copyofrange_validated()) {
1049 es = PointsToNode::NoEscape;
1050 }
1051 }
1052 set_escape_state(arg_ptn, es);
1053 if (arg_is_arraycopy_dest) {
1054 Node* src = call->in(TypeFunc::Parms);
1055 if (src->is_AddP()) {
1056 src = get_addp_base(src);
1057 }
1058 PointsToNode* src_ptn = ptnode_adr(src->_idx);
1059 assert(src_ptn != NULL, "should be registered");
1060 if (arg_ptn != src_ptn) {
1061 // Special arraycopy edge:
1062 // A destination object's field can't have the source object
1063 // as base since objects escape states are not related.
1064 // Only escape state of destination object's fields affects
1065 // escape state of fields in source object.
1066 add_arraycopy(call, es, src_ptn, arg_ptn);
1067 }
1068 }
1069 }
1070 }
1071 break;
1072 }
1073 case Op_CallStaticJava: {
1074 // For a static call, we know exactly what method is being called.
1075 // Use bytecode estimator to record the call's escape affects
1076 #ifdef ASSERT
1077 const char* name = call->as_CallStaticJava()->_name;
1078 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only");
1079 #endif
1080 ciMethod* meth = call->as_CallJava()->method();
1081 if ((meth != NULL) && meth->is_boxing_method()) {
1082 break; // Boxing methods do not modify any oops.
1083 }
1084 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
1085 // fall-through if not a Java method or no analyzer information
1086 if (call_analyzer != NULL) {
1087 PointsToNode* call_ptn = ptnode_adr(call->_idx);
1088 const TypeTuple* d = call->tf()->domain_cc();
1089 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1090 const Type* at = d->field_at(i);
1091 int k = i - TypeFunc::Parms;
1092 Node* arg = call->in(i);
1093 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1094 if (at->isa_ptr() != NULL &&
1095 call_analyzer->is_arg_returned(k)) {
1096 // The call returns arguments.
1097 if (call_ptn != NULL) { // Is call's result used?
1098 assert(call_ptn->is_LocalVar(), "node should be registered");
1099 assert(arg_ptn != NULL, "node should be registered");
1100 add_edge(call_ptn, arg_ptn);
1101 }
1102 }
1103 if (at->isa_oopptr() != NULL &&
1104 arg_ptn->escape_state() < PointsToNode::GlobalEscape) {
1105 if (!call_analyzer->is_arg_stack(k)) {
1106 // The argument global escapes
1107 set_escape_state(arg_ptn, PointsToNode::GlobalEscape);
1108 } else {
1109 set_escape_state(arg_ptn, PointsToNode::ArgEscape);
1110 if (!call_analyzer->is_arg_local(k)) {
1111 // The argument itself doesn't escape, but any fields might
1112 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape);
1113 }
1114 }
1115 }
1116 }
1117 if (call_ptn != NULL && call_ptn->is_LocalVar()) {
1118 // The call returns arguments.
1119 assert(call_ptn->edge_count() > 0, "sanity");
1120 if (!call_analyzer->is_return_local()) {
1121 // Returns also unknown object.
1122 add_edge(call_ptn, phantom_obj);
1123 }
1124 }
1125 break;
1126 }
1127 }
1128 default: {
1129 // Fall-through here if not a Java method or no analyzer information
1130 // or some other type of call, assume the worst case: all arguments
1131 // globally escape.
1132 const TypeTuple* d = call->tf()->domain_cc();
1133 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1134 const Type* at = d->field_at(i);
1135 if (at->isa_oopptr() != NULL) {
1136 Node* arg = call->in(i);
1137 if (arg->is_AddP()) {
1138 arg = get_addp_base(arg);
1139 }
1140 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already");
1141 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape);
1142 }
1143 }
1144 }
1145 }
1146 }
1147
1148
1149 // Finish Graph construction.
1150 bool ConnectionGraph::complete_connection_graph(
1151 GrowableArray<PointsToNode*>& ptnodes_worklist,
1152 GrowableArray<JavaObjectNode*>& non_escaped_worklist,
1153 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1154 GrowableArray<FieldNode*>& oop_fields_worklist) {
1155 // Normally only 1-3 passes needed to build Connection Graph depending
1156 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler.
1157 // Set limit to 20 to catch situation when something did go wrong and
1158 // bailout Escape Analysis.
1159 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag.
1160 #define CG_BUILD_ITER_LIMIT 20
1161
1162 // Propagate GlobalEscape and ArgEscape escape states and check that
1163 // we still have non-escaping objects. The method pushs on _worklist
1164 // Field nodes which reference phantom_object.
1165 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) {
1166 return false; // Nothing to do.
1167 }
1168 // Now propagate references to all JavaObject nodes.
1169 int java_objects_length = java_objects_worklist.length();
1170 elapsedTimer time;
1171 bool timeout = false;
1172 int new_edges = 1;
1173 int iterations = 0;
1174 do {
1175 while ((new_edges > 0) &&
1176 (iterations++ < CG_BUILD_ITER_LIMIT)) {
1177 double start_time = time.seconds();
1178 time.start();
1179 new_edges = 0;
1180 // Propagate references to phantom_object for nodes pushed on _worklist
1181 // by find_non_escaped_objects() and find_field_value().
1182 new_edges += add_java_object_edges(phantom_obj, false);
1183 for (int next = 0; next < java_objects_length; ++next) {
1184 JavaObjectNode* ptn = java_objects_worklist.at(next);
1185 new_edges += add_java_object_edges(ptn, true);
1186
1187 #define SAMPLE_SIZE 4
1188 if ((next % SAMPLE_SIZE) == 0) {
1189 // Each 4 iterations calculate how much time it will take
1190 // to complete graph construction.
1191 time.stop();
1192 // Poll for requests from shutdown mechanism to quiesce compiler
1193 // because Connection graph construction may take long time.
1194 CompileBroker::maybe_block();
1195 double stop_time = time.seconds();
1196 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE;
1197 double time_until_end = time_per_iter * (double)(java_objects_length - next);
1198 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) {
1199 timeout = true;
1200 break; // Timeout
1201 }
1202 start_time = stop_time;
1203 time.start();
1204 }
1205 #undef SAMPLE_SIZE
1206
1207 }
1208 if (timeout) break;
1209 if (new_edges > 0) {
1210 // Update escape states on each iteration if graph was updated.
1211 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) {
1212 return false; // Nothing to do.
1213 }
1214 }
1215 time.stop();
1216 if (time.seconds() >= EscapeAnalysisTimeout) {
1217 timeout = true;
1218 break;
1219 }
1220 }
1221 if ((iterations < CG_BUILD_ITER_LIMIT) && !timeout) {
1222 time.start();
1223 // Find fields which have unknown value.
1224 int fields_length = oop_fields_worklist.length();
1225 for (int next = 0; next < fields_length; next++) {
1226 FieldNode* field = oop_fields_worklist.at(next);
1227 if (field->edge_count() == 0) {
1228 new_edges += find_field_value(field);
1229 // This code may added new edges to phantom_object.
1230 // Need an other cycle to propagate references to phantom_object.
1231 }
1232 }
1233 time.stop();
1234 if (time.seconds() >= EscapeAnalysisTimeout) {
1235 timeout = true;
1236 break;
1237 }
1238 } else {
1239 new_edges = 0; // Bailout
1240 }
1241 } while (new_edges > 0);
1242
1243 // Bailout if passed limits.
1244 if ((iterations >= CG_BUILD_ITER_LIMIT) || timeout) {
1245 Compile* C = _compile;
1246 if (C->log() != NULL) {
1247 C->log()->begin_elem("connectionGraph_bailout reason='reached ");
1248 C->log()->text("%s", timeout ? "time" : "iterations");
1249 C->log()->end_elem(" limit'");
1250 }
1251 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d",
1252 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length());
1253 // Possible infinite build_connection_graph loop,
1254 // bailout (no changes to ideal graph were made).
1255 return false;
1256 }
1257 #ifdef ASSERT
1258 if (Verbose && PrintEscapeAnalysis) {
1259 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d",
1260 iterations, nodes_size(), ptnodes_worklist.length());
1261 }
1262 #endif
1263
1264 #undef CG_BUILD_ITER_LIMIT
1265
1266 // Find fields initialized by NULL for non-escaping Allocations.
1267 int non_escaped_length = non_escaped_worklist.length();
1268 for (int next = 0; next < non_escaped_length; next++) {
1269 JavaObjectNode* ptn = non_escaped_worklist.at(next);
1270 PointsToNode::EscapeState es = ptn->escape_state();
1271 assert(es <= PointsToNode::ArgEscape, "sanity");
1272 if (es == PointsToNode::NoEscape) {
1273 if (find_init_values(ptn, null_obj, _igvn) > 0) {
1274 // Adding references to NULL object does not change escape states
1275 // since it does not escape. Also no fields are added to NULL object.
1276 add_java_object_edges(null_obj, false);
1277 }
1278 }
1279 Node* n = ptn->ideal_node();
1280 if (n->is_Allocate()) {
1281 // The object allocated by this Allocate node will never be
1282 // seen by an other thread. Mark it so that when it is
1283 // expanded no MemBarStoreStore is added.
1284 InitializeNode* ini = n->as_Allocate()->initialization();
1285 if (ini != NULL)
1286 ini->set_does_not_escape();
1287 }
1288 }
1289 return true; // Finished graph construction.
1290 }
1291
1292 // Propagate GlobalEscape and ArgEscape escape states to all nodes
1293 // and check that we still have non-escaping java objects.
1294 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist,
1295 GrowableArray<JavaObjectNode*>& non_escaped_worklist) {
1296 GrowableArray<PointsToNode*> escape_worklist;
1297 // First, put all nodes with GlobalEscape and ArgEscape states on worklist.
1298 int ptnodes_length = ptnodes_worklist.length();
1299 for (int next = 0; next < ptnodes_length; ++next) {
1300 PointsToNode* ptn = ptnodes_worklist.at(next);
1301 if (ptn->escape_state() >= PointsToNode::ArgEscape ||
1302 ptn->fields_escape_state() >= PointsToNode::ArgEscape) {
1303 escape_worklist.push(ptn);
1304 }
1305 }
1306 // Set escape states to referenced nodes (edges list).
1307 while (escape_worklist.length() > 0) {
1308 PointsToNode* ptn = escape_worklist.pop();
1309 PointsToNode::EscapeState es = ptn->escape_state();
1310 PointsToNode::EscapeState field_es = ptn->fields_escape_state();
1311 if (ptn->is_Field() && ptn->as_Field()->is_oop() &&
1312 es >= PointsToNode::ArgEscape) {
1313 // GlobalEscape or ArgEscape state of field means it has unknown value.
1314 if (add_edge(ptn, phantom_obj)) {
1315 // New edge was added
1316 add_field_uses_to_worklist(ptn->as_Field());
1317 }
1318 }
1319 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1320 PointsToNode* e = i.get();
1321 if (e->is_Arraycopy()) {
1322 assert(ptn->arraycopy_dst(), "sanity");
1323 // Propagate only fields escape state through arraycopy edge.
1324 if (e->fields_escape_state() < field_es) {
1325 set_fields_escape_state(e, field_es);
1326 escape_worklist.push(e);
1327 }
1328 } else if (es >= field_es) {
1329 // fields_escape_state is also set to 'es' if it is less than 'es'.
1330 if (e->escape_state() < es) {
1331 set_escape_state(e, es);
1332 escape_worklist.push(e);
1333 }
1334 } else {
1335 // Propagate field escape state.
1336 bool es_changed = false;
1337 if (e->fields_escape_state() < field_es) {
1338 set_fields_escape_state(e, field_es);
1339 es_changed = true;
1340 }
1341 if ((e->escape_state() < field_es) &&
1342 e->is_Field() && ptn->is_JavaObject() &&
1343 e->as_Field()->is_oop()) {
1344 // Change escape state of referenced fields.
1345 set_escape_state(e, field_es);
1346 es_changed = true;
1347 } else if (e->escape_state() < es) {
1348 set_escape_state(e, es);
1349 es_changed = true;
1350 }
1351 if (es_changed) {
1352 escape_worklist.push(e);
1353 }
1354 }
1355 }
1356 }
1357 // Remove escaped objects from non_escaped list.
1358 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) {
1359 JavaObjectNode* ptn = non_escaped_worklist.at(next);
1360 if (ptn->escape_state() >= PointsToNode::GlobalEscape) {
1361 non_escaped_worklist.delete_at(next);
1362 }
1363 if (ptn->escape_state() == PointsToNode::NoEscape) {
1364 // Find fields in non-escaped allocations which have unknown value.
1365 find_init_values(ptn, phantom_obj, NULL);
1366 }
1367 }
1368 return (non_escaped_worklist.length() > 0);
1369 }
1370
1371 // Add all references to JavaObject node by walking over all uses.
1372 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) {
1373 int new_edges = 0;
1374 if (populate_worklist) {
1375 // Populate _worklist by uses of jobj's uses.
1376 for (UseIterator i(jobj); i.has_next(); i.next()) {
1377 PointsToNode* use = i.get();
1378 if (use->is_Arraycopy())
1379 continue;
1380 add_uses_to_worklist(use);
1381 if (use->is_Field() && use->as_Field()->is_oop()) {
1382 // Put on worklist all field's uses (loads) and
1383 // related field nodes (same base and offset).
1384 add_field_uses_to_worklist(use->as_Field());
1385 }
1386 }
1387 }
1388 for (int l = 0; l < _worklist.length(); l++) {
1389 PointsToNode* use = _worklist.at(l);
1390 if (PointsToNode::is_base_use(use)) {
1391 // Add reference from jobj to field and from field to jobj (field's base).
1392 use = PointsToNode::get_use_node(use)->as_Field();
1393 if (add_base(use->as_Field(), jobj)) {
1394 new_edges++;
1395 }
1396 continue;
1397 }
1398 assert(!use->is_JavaObject(), "sanity");
1399 if (use->is_Arraycopy()) {
1400 if (jobj == null_obj) // NULL object does not have field edges
1401 continue;
1402 // Added edge from Arraycopy node to arraycopy's source java object
1403 if (add_edge(use, jobj)) {
1404 jobj->set_arraycopy_src();
1405 new_edges++;
1406 }
1407 // and stop here.
1408 continue;
1409 }
1410 if (!add_edge(use, jobj))
1411 continue; // No new edge added, there was such edge already.
1412 new_edges++;
1413 if (use->is_LocalVar()) {
1414 add_uses_to_worklist(use);
1415 if (use->arraycopy_dst()) {
1416 for (EdgeIterator i(use); i.has_next(); i.next()) {
1417 PointsToNode* e = i.get();
1418 if (e->is_Arraycopy()) {
1419 if (jobj == null_obj) // NULL object does not have field edges
1420 continue;
1421 // Add edge from arraycopy's destination java object to Arraycopy node.
1422 if (add_edge(jobj, e)) {
1423 new_edges++;
1424 jobj->set_arraycopy_dst();
1425 }
1426 }
1427 }
1428 }
1429 } else {
1430 // Added new edge to stored in field values.
1431 // Put on worklist all field's uses (loads) and
1432 // related field nodes (same base and offset).
1433 add_field_uses_to_worklist(use->as_Field());
1434 }
1435 }
1436 _worklist.clear();
1437 _in_worklist.Reset();
1438 return new_edges;
1439 }
1440
1441 // Put on worklist all related field nodes.
1442 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) {
1443 assert(field->is_oop(), "sanity");
1444 int offset = field->offset();
1445 add_uses_to_worklist(field);
1446 // Loop over all bases of this field and push on worklist Field nodes
1447 // with the same offset and base (since they may reference the same field).
1448 for (BaseIterator i(field); i.has_next(); i.next()) {
1449 PointsToNode* base = i.get();
1450 add_fields_to_worklist(field, base);
1451 // Check if the base was source object of arraycopy and go over arraycopy's
1452 // destination objects since values stored to a field of source object are
1453 // accessable by uses (loads) of fields of destination objects.
1454 if (base->arraycopy_src()) {
1455 for (UseIterator j(base); j.has_next(); j.next()) {
1456 PointsToNode* arycp = j.get();
1457 if (arycp->is_Arraycopy()) {
1458 for (UseIterator k(arycp); k.has_next(); k.next()) {
1459 PointsToNode* abase = k.get();
1460 if (abase->arraycopy_dst() && abase != base) {
1461 // Look for the same arraycopy reference.
1462 add_fields_to_worklist(field, abase);
1463 }
1464 }
1465 }
1466 }
1467 }
1468 }
1469 }
1470
1471 // Put on worklist all related field nodes.
1472 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) {
1473 int offset = field->offset();
1474 if (base->is_LocalVar()) {
1475 for (UseIterator j(base); j.has_next(); j.next()) {
1476 PointsToNode* f = j.get();
1477 if (PointsToNode::is_base_use(f)) { // Field
1478 f = PointsToNode::get_use_node(f);
1479 if (f == field || !f->as_Field()->is_oop())
1480 continue;
1481 int offs = f->as_Field()->offset();
1482 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1483 add_to_worklist(f);
1484 }
1485 }
1486 }
1487 } else {
1488 assert(base->is_JavaObject(), "sanity");
1489 if (// Skip phantom_object since it is only used to indicate that
1490 // this field's content globally escapes.
1491 (base != phantom_obj) &&
1492 // NULL object node does not have fields.
1493 (base != null_obj)) {
1494 for (EdgeIterator i(base); i.has_next(); i.next()) {
1495 PointsToNode* f = i.get();
1496 // Skip arraycopy edge since store to destination object field
1497 // does not update value in source object field.
1498 if (f->is_Arraycopy()) {
1499 assert(base->arraycopy_dst(), "sanity");
1500 continue;
1501 }
1502 if (f == field || !f->as_Field()->is_oop())
1503 continue;
1504 int offs = f->as_Field()->offset();
1505 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1506 add_to_worklist(f);
1507 }
1508 }
1509 }
1510 }
1511 }
1512
1513 // Find fields which have unknown value.
1514 int ConnectionGraph::find_field_value(FieldNode* field) {
1515 // Escaped fields should have init value already.
1516 assert(field->escape_state() == PointsToNode::NoEscape, "sanity");
1517 int new_edges = 0;
1518 for (BaseIterator i(field); i.has_next(); i.next()) {
1519 PointsToNode* base = i.get();
1520 if (base->is_JavaObject()) {
1521 // Skip Allocate's fields which will be processed later.
1522 if (base->ideal_node()->is_Allocate())
1523 return 0;
1524 assert(base == null_obj, "only NULL ptr base expected here");
1525 }
1526 }
1527 if (add_edge(field, phantom_obj)) {
1528 // New edge was added
1529 new_edges++;
1530 add_field_uses_to_worklist(field);
1531 }
1532 return new_edges;
1533 }
1534
1535 // Find fields initializing values for allocations.
1536 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) {
1537 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
1538 int new_edges = 0;
1539 Node* alloc = pta->ideal_node();
1540 if (init_val == phantom_obj) {
1541 // Do nothing for Allocate nodes since its fields values are
1542 // "known" unless they are initialized by arraycopy/clone.
1543 if (alloc->is_Allocate() && !pta->arraycopy_dst())
1544 return 0;
1545 assert(pta->arraycopy_dst() || alloc->as_CallStaticJava(), "sanity");
1546 #ifdef ASSERT
1547 if (!pta->arraycopy_dst() && alloc->as_CallStaticJava()->method() == NULL) {
1548 const char* name = alloc->as_CallStaticJava()->_name;
1549 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity");
1550 }
1551 #endif
1552 // Non-escaped allocation returned from Java or runtime call have
1553 // unknown values in fields.
1554 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1555 PointsToNode* field = i.get();
1556 if (field->is_Field() && field->as_Field()->is_oop()) {
1557 if (add_edge(field, phantom_obj)) {
1558 // New edge was added
1559 new_edges++;
1560 add_field_uses_to_worklist(field->as_Field());
1561 }
1562 }
1563 }
1564 return new_edges;
1565 }
1566 assert(init_val == null_obj, "sanity");
1567 // Do nothing for Call nodes since its fields values are unknown.
1568 if (!alloc->is_Allocate())
1569 return 0;
1570
1571 InitializeNode* ini = alloc->as_Allocate()->initialization();
1572 bool visited_bottom_offset = false;
1573 GrowableArray<int> offsets_worklist;
1574
1575 // Check if an oop field's initializing value is recorded and add
1576 // a corresponding NULL if field's value if it is not recorded.
1577 // Connection Graph does not record a default initialization by NULL
1578 // captured by Initialize node.
1579 //
1580 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1581 PointsToNode* field = i.get(); // Field (AddP)
1582 if (!field->is_Field() || !field->as_Field()->is_oop())
1583 continue; // Not oop field
1584 int offset = field->as_Field()->offset();
1585 if (offset == Type::OffsetBot) {
1586 if (!visited_bottom_offset) {
1587 // OffsetBot is used to reference array's element,
1588 // always add reference to NULL to all Field nodes since we don't
1589 // known which element is referenced.
1590 if (add_edge(field, null_obj)) {
1591 // New edge was added
1592 new_edges++;
1593 add_field_uses_to_worklist(field->as_Field());
1594 visited_bottom_offset = true;
1595 }
1596 }
1597 } else {
1598 // Check only oop fields.
1599 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type();
1600 if (adr_type->isa_rawptr()) {
1601 #ifdef ASSERT
1602 // Raw pointers are used for initializing stores so skip it
1603 // since it should be recorded already
1604 Node* base = get_addp_base(field->ideal_node());
1605 assert(adr_type->isa_rawptr() && base->is_Proj() &&
1606 (base->in(0) == alloc),"unexpected pointer type");
1607 #endif
1608 continue;
1609 }
1610 if (!offsets_worklist.contains(offset)) {
1611 offsets_worklist.append(offset);
1612 Node* value = NULL;
1613 if (ini != NULL) {
1614 // StoreP::memory_type() == T_ADDRESS
1615 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS;
1616 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase);
1617 // Make sure initializing store has the same type as this AddP.
1618 // This AddP may reference non existing field because it is on a
1619 // dead branch of bimorphic call which is not eliminated yet.
1620 if (store != NULL && store->is_Store() &&
1621 store->as_Store()->memory_type() == ft) {
1622 value = store->in(MemNode::ValueIn);
1623 #ifdef ASSERT
1624 if (VerifyConnectionGraph) {
1625 // Verify that AddP already points to all objects the value points to.
1626 PointsToNode* val = ptnode_adr(value->_idx);
1627 assert((val != NULL), "should be processed already");
1628 PointsToNode* missed_obj = NULL;
1629 if (val->is_JavaObject()) {
1630 if (!field->points_to(val->as_JavaObject())) {
1631 missed_obj = val;
1632 }
1633 } else {
1634 if (!val->is_LocalVar() || (val->edge_count() == 0)) {
1635 tty->print_cr("----------init store has invalid value -----");
1636 store->dump();
1637 val->dump();
1638 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already");
1639 }
1640 for (EdgeIterator j(val); j.has_next(); j.next()) {
1641 PointsToNode* obj = j.get();
1642 if (obj->is_JavaObject()) {
1643 if (!field->points_to(obj->as_JavaObject())) {
1644 missed_obj = obj;
1645 break;
1646 }
1647 }
1648 }
1649 }
1650 if (missed_obj != NULL) {
1651 tty->print_cr("----------field---------------------------------");
1652 field->dump();
1653 tty->print_cr("----------missed referernce to object-----------");
1654 missed_obj->dump();
1655 tty->print_cr("----------object referernced by init store -----");
1656 store->dump();
1657 val->dump();
1658 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference");
1659 }
1660 }
1661 #endif
1662 } else {
1663 // There could be initializing stores which follow allocation.
1664 // For example, a volatile field store is not collected
1665 // by Initialize node.
1666 //
1667 // Need to check for dependent loads to separate such stores from
1668 // stores which follow loads. For now, add initial value NULL so
1669 // that compare pointers optimization works correctly.
1670 }
1671 }
1672 if (value == NULL) {
1673 // A field's initializing value was not recorded. Add NULL.
1674 if (add_edge(field, null_obj)) {
1675 // New edge was added
1676 new_edges++;
1677 add_field_uses_to_worklist(field->as_Field());
1678 }
1679 }
1680 }
1681 }
1682 }
1683 return new_edges;
1684 }
1685
1686 // Adjust scalar_replaceable state after Connection Graph is built.
1687 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) {
1688 // Search for non-escaping objects which are not scalar replaceable
1689 // and mark them to propagate the state to referenced objects.
1690
1691 // 1. An object is not scalar replaceable if the field into which it is
1692 // stored has unknown offset (stored into unknown element of an array).
1693 //
1694 for (UseIterator i(jobj); i.has_next(); i.next()) {
1695 PointsToNode* use = i.get();
1696 if (use->is_Arraycopy()) {
1697 continue;
1698 }
1699 if (use->is_Field()) {
1700 FieldNode* field = use->as_Field();
1701 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
1702 if (field->offset() == Type::OffsetBot) {
1703 jobj->set_scalar_replaceable(false);
1704 return;
1705 }
1706 // 2. An object is not scalar replaceable if the field into which it is
1707 // stored has multiple bases one of which is null.
1708 if (field->base_count() > 1) {
1709 for (BaseIterator i(field); i.has_next(); i.next()) {
1710 PointsToNode* base = i.get();
1711 if (base == null_obj) {
1712 jobj->set_scalar_replaceable(false);
1713 return;
1714 }
1715 }
1716 }
1717 }
1718 assert(use->is_Field() || use->is_LocalVar(), "sanity");
1719 // 3. An object is not scalar replaceable if it is merged with other objects.
1720 for (EdgeIterator j(use); j.has_next(); j.next()) {
1721 PointsToNode* ptn = j.get();
1722 if (ptn->is_JavaObject() && ptn != jobj) {
1723 // Mark all objects.
1724 jobj->set_scalar_replaceable(false);
1725 ptn->set_scalar_replaceable(false);
1726 }
1727 }
1728 if (!jobj->scalar_replaceable()) {
1729 return;
1730 }
1731 }
1732
1733 for (EdgeIterator j(jobj); j.has_next(); j.next()) {
1734 if (j.get()->is_Arraycopy()) {
1735 continue;
1736 }
1737
1738 // Non-escaping object node should point only to field nodes.
1739 FieldNode* field = j.get()->as_Field();
1740 int offset = field->as_Field()->offset();
1741
1742 // 4. An object is not scalar replaceable if it has a field with unknown
1743 // offset (array's element is accessed in loop).
1744 if (offset == Type::OffsetBot) {
1745 jobj->set_scalar_replaceable(false);
1746 return;
1747 }
1748 // 5. Currently an object is not scalar replaceable if a LoadStore node
1749 // access its field since the field value is unknown after it.
1750 //
1751 Node* n = field->ideal_node();
1752 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1753 if (n->fast_out(i)->is_LoadStore()) {
1754 jobj->set_scalar_replaceable(false);
1755 return;
1756 }
1757 }
1758
1759 // 6. Or the address may point to more then one object. This may produce
1760 // the false positive result (set not scalar replaceable)
1761 // since the flow-insensitive escape analysis can't separate
1762 // the case when stores overwrite the field's value from the case
1763 // when stores happened on different control branches.
1764 //
1765 // Note: it will disable scalar replacement in some cases:
1766 //
1767 // Point p[] = new Point[1];
1768 // p[0] = new Point(); // Will be not scalar replaced
1769 //
1770 // but it will save us from incorrect optimizations in next cases:
1771 //
1772 // Point p[] = new Point[1];
1773 // if ( x ) p[0] = new Point(); // Will be not scalar replaced
1774 //
1775 if (field->base_count() > 1) {
1776 for (BaseIterator i(field); i.has_next(); i.next()) {
1777 PointsToNode* base = i.get();
1778 // Don't take into account LocalVar nodes which
1779 // may point to only one object which should be also
1780 // this field's base by now.
1781 if (base->is_JavaObject() && base != jobj) {
1782 // Mark all bases.
1783 jobj->set_scalar_replaceable(false);
1784 base->set_scalar_replaceable(false);
1785 }
1786 }
1787 }
1788 }
1789 }
1790
1791 #ifdef ASSERT
1792 void ConnectionGraph::verify_connection_graph(
1793 GrowableArray<PointsToNode*>& ptnodes_worklist,
1794 GrowableArray<JavaObjectNode*>& non_escaped_worklist,
1795 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1796 GrowableArray<Node*>& addp_worklist) {
1797 // Verify that graph is complete - no new edges could be added.
1798 int java_objects_length = java_objects_worklist.length();
1799 int non_escaped_length = non_escaped_worklist.length();
1800 int new_edges = 0;
1801 for (int next = 0; next < java_objects_length; ++next) {
1802 JavaObjectNode* ptn = java_objects_worklist.at(next);
1803 new_edges += add_java_object_edges(ptn, true);
1804 }
1805 assert(new_edges == 0, "graph was not complete");
1806 // Verify that escape state is final.
1807 int length = non_escaped_worklist.length();
1808 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist);
1809 assert((non_escaped_length == non_escaped_worklist.length()) &&
1810 (non_escaped_length == length) &&
1811 (_worklist.length() == 0), "escape state was not final");
1812
1813 // Verify fields information.
1814 int addp_length = addp_worklist.length();
1815 for (int next = 0; next < addp_length; ++next ) {
1816 Node* n = addp_worklist.at(next);
1817 FieldNode* field = ptnode_adr(n->_idx)->as_Field();
1818 if (field->is_oop()) {
1819 // Verify that field has all bases
1820 Node* base = get_addp_base(n);
1821 PointsToNode* ptn = ptnode_adr(base->_idx);
1822 if (ptn->is_JavaObject()) {
1823 assert(field->has_base(ptn->as_JavaObject()), "sanity");
1824 } else {
1825 assert(ptn->is_LocalVar(), "sanity");
1826 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1827 PointsToNode* e = i.get();
1828 if (e->is_JavaObject()) {
1829 assert(field->has_base(e->as_JavaObject()), "sanity");
1830 }
1831 }
1832 }
1833 // Verify that all fields have initializing values.
1834 if (field->edge_count() == 0) {
1835 tty->print_cr("----------field does not have references----------");
1836 field->dump();
1837 for (BaseIterator i(field); i.has_next(); i.next()) {
1838 PointsToNode* base = i.get();
1839 tty->print_cr("----------field has next base---------------------");
1840 base->dump();
1841 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) {
1842 tty->print_cr("----------base has fields-------------------------");
1843 for (EdgeIterator j(base); j.has_next(); j.next()) {
1844 j.get()->dump();
1845 }
1846 tty->print_cr("----------base has references---------------------");
1847 for (UseIterator j(base); j.has_next(); j.next()) {
1848 j.get()->dump();
1849 }
1850 }
1851 }
1852 for (UseIterator i(field); i.has_next(); i.next()) {
1853 i.get()->dump();
1854 }
1855 assert(field->edge_count() > 0, "sanity");
1856 }
1857 }
1858 }
1859 }
1860 #endif
1861
1862 // Optimize ideal graph.
1863 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist,
1864 GrowableArray<Node*>& storestore_worklist) {
1865 Compile* C = _compile;
1866 PhaseIterGVN* igvn = _igvn;
1867 if (EliminateLocks) {
1868 // Mark locks before changing ideal graph.
1869 int cnt = C->macro_count();
1870 for( int i=0; i < cnt; i++ ) {
1871 Node *n = C->macro_node(i);
1872 if (n->is_AbstractLock()) { // Lock and Unlock nodes
1873 AbstractLockNode* alock = n->as_AbstractLock();
1874 if (!alock->is_non_esc_obj()) {
1875 if (not_global_escape(alock->obj_node())) {
1876 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity");
1877 // The lock could be marked eliminated by lock coarsening
1878 // code during first IGVN before EA. Replace coarsened flag
1879 // to eliminate all associated locks/unlocks.
1880 #ifdef ASSERT
1881 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3");
1882 #endif
1883 alock->set_non_esc_obj();
1884 }
1885 }
1886 }
1887 }
1888 }
1889
1890 if (OptimizePtrCompare) {
1891 // Add ConI(#CC_GT) and ConI(#CC_EQ).
1892 _pcmp_neq = igvn->makecon(TypeInt::CC_GT);
1893 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ);
1894 // Optimize objects compare.
1895 while (ptr_cmp_worklist.length() != 0) {
1896 Node *n = ptr_cmp_worklist.pop();
1897 Node *res = optimize_ptr_compare(n);
1898 if (res != NULL) {
1899 #ifndef PRODUCT
1900 if (PrintOptimizePtrCompare) {
1901 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"));
1902 if (Verbose) {
1903 n->dump(1);
1904 }
1905 }
1906 #endif
1907 igvn->replace_node(n, res);
1908 }
1909 }
1910 // cleanup
1911 if (_pcmp_neq->outcnt() == 0)
1912 igvn->hash_delete(_pcmp_neq);
1913 if (_pcmp_eq->outcnt() == 0)
1914 igvn->hash_delete(_pcmp_eq);
1915 }
1916
1917 // For MemBarStoreStore nodes added in library_call.cpp, check
1918 // escape status of associated AllocateNode and optimize out
1919 // MemBarStoreStore node if the allocated object never escapes.
1920 while (storestore_worklist.length() != 0) {
1921 Node *n = storestore_worklist.pop();
1922 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore();
1923 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0);
1924 assert (alloc->is_Allocate(), "storestore should point to AllocateNode");
1925 if (not_global_escape(alloc)) {
1926 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot);
1927 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory));
1928 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control));
1929 igvn->register_new_node_with_optimizer(mb);
1930 igvn->replace_node(storestore, mb);
1931 }
1932 }
1933 }
1934
1935 // Optimize objects compare.
1936 Node* ConnectionGraph::optimize_ptr_compare(Node* n) {
1937 assert(OptimizePtrCompare, "sanity");
1938 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx);
1939 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx);
1940 JavaObjectNode* jobj1 = unique_java_object(n->in(1));
1941 JavaObjectNode* jobj2 = unique_java_object(n->in(2));
1942 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity");
1943 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity");
1944
1945 // Check simple cases first.
1946 if (jobj1 != NULL) {
1947 if (jobj1->escape_state() == PointsToNode::NoEscape) {
1948 if (jobj1 == jobj2) {
1949 // Comparing the same not escaping object.
1950 return _pcmp_eq;
1951 }
1952 Node* obj = jobj1->ideal_node();
1953 // Comparing not escaping allocation.
1954 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
1955 !ptn2->points_to(jobj1)) {
1956 return _pcmp_neq; // This includes nullness check.
1957 }
1958 }
1959 }
1960 if (jobj2 != NULL) {
1961 if (jobj2->escape_state() == PointsToNode::NoEscape) {
1962 Node* obj = jobj2->ideal_node();
1963 // Comparing not escaping allocation.
1964 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
1965 !ptn1->points_to(jobj2)) {
1966 return _pcmp_neq; // This includes nullness check.
1967 }
1968 }
1969 }
1970 if (jobj1 != NULL && jobj1 != phantom_obj &&
1971 jobj2 != NULL && jobj2 != phantom_obj &&
1972 jobj1->ideal_node()->is_Con() &&
1973 jobj2->ideal_node()->is_Con()) {
1974 // Klass or String constants compare. Need to be careful with
1975 // compressed pointers - compare types of ConN and ConP instead of nodes.
1976 const Type* t1 = jobj1->ideal_node()->get_ptr_type();
1977 const Type* t2 = jobj2->ideal_node()->get_ptr_type();
1978 if (t1->make_ptr() == t2->make_ptr()) {
1979 return _pcmp_eq;
1980 } else {
1981 return _pcmp_neq;
1982 }
1983 }
1984 if (ptn1->meet(ptn2)) {
1985 return NULL; // Sets are not disjoint
1986 }
1987
1988 // Sets are disjoint.
1989 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj);
1990 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj);
1991 bool set1_has_null_ptr = ptn1->points_to(null_obj);
1992 bool set2_has_null_ptr = ptn2->points_to(null_obj);
1993 if (set1_has_unknown_ptr && set2_has_null_ptr ||
1994 set2_has_unknown_ptr && set1_has_null_ptr) {
1995 // Check nullness of unknown object.
1996 return NULL;
1997 }
1998
1999 // Disjointness by itself is not sufficient since
2000 // alias analysis is not complete for escaped objects.
2001 // Disjoint sets are definitely unrelated only when
2002 // at least one set has only not escaping allocations.
2003 if (!set1_has_unknown_ptr && !set1_has_null_ptr) {
2004 if (ptn1->non_escaping_allocation()) {
2005 return _pcmp_neq;
2006 }
2007 }
2008 if (!set2_has_unknown_ptr && !set2_has_null_ptr) {
2009 if (ptn2->non_escaping_allocation()) {
2010 return _pcmp_neq;
2011 }
2012 }
2013 return NULL;
2014 }
2015
2016 // Connection Graph constuction functions.
2017
2018 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) {
2019 PointsToNode* ptadr = _nodes.at(n->_idx);
2020 if (ptadr != NULL) {
2021 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity");
2022 return;
2023 }
2024 Compile* C = _compile;
2025 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es);
2026 _nodes.at_put(n->_idx, ptadr);
2027 }
2028
2029 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) {
2030 PointsToNode* ptadr = _nodes.at(n->_idx);
2031 if (ptadr != NULL) {
2032 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity");
2033 return;
2034 }
2035 Compile* C = _compile;
2036 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es);
2037 _nodes.at_put(n->_idx, ptadr);
2038 }
2039
2040 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) {
2041 PointsToNode* ptadr = _nodes.at(n->_idx);
2042 if (ptadr != NULL) {
2043 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity");
2044 return;
2045 }
2046 bool unsafe = false;
2047 bool is_oop = is_oop_field(n, offset, &unsafe);
2048 if (unsafe) {
2049 es = PointsToNode::GlobalEscape;
2050 }
2051 Compile* C = _compile;
2052 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop);
2053 _nodes.at_put(n->_idx, field);
2054 }
2055
2056 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es,
2057 PointsToNode* src, PointsToNode* dst) {
2058 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar");
2059 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL");
2060 PointsToNode* ptadr = _nodes.at(n->_idx);
2061 if (ptadr != NULL) {
2062 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity");
2063 return;
2064 }
2065 Compile* C = _compile;
2066 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es);
2067 _nodes.at_put(n->_idx, ptadr);
2068 // Add edge from arraycopy node to source object.
2069 (void)add_edge(ptadr, src);
2070 src->set_arraycopy_src();
2071 // Add edge from destination object to arraycopy node.
2072 (void)add_edge(dst, ptadr);
2073 dst->set_arraycopy_dst();
2074 }
2075
2076 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) {
2077 const Type* adr_type = n->as_AddP()->bottom_type();
2078 int field_offset = adr_type->isa_aryptr() ? adr_type->isa_aryptr()->field_offset().get() : Type::OffsetBot;
2079 BasicType bt = T_INT;
2080 if (offset == Type::OffsetBot && field_offset == Type::OffsetBot) {
2081 // Check only oop fields.
2082 if (!adr_type->isa_aryptr() ||
2083 (adr_type->isa_aryptr()->klass() == NULL) ||
2084 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) {
2085 // OffsetBot is used to reference array's element. Ignore first AddP.
2086 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) {
2087 bt = T_OBJECT;
2088 }
2089 }
2090 } else if (offset != oopDesc::klass_offset_in_bytes()) {
2091 if (adr_type->isa_instptr() || adr_type->isa_valuetypeptr()) {
2092 ciField* field = _compile->alias_type(adr_type->is_ptr())->field();
2093 if (field != NULL) {
2094 bt = field->layout_type();
2095 } else {
2096 // Check for unsafe oop field access
2097 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2098 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2099 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) {
2100 bt = T_OBJECT;
2101 (*unsafe) = true;
2102 }
2103 }
2104 } else if (adr_type->isa_aryptr()) {
2105 if (offset == arrayOopDesc::length_offset_in_bytes()) {
2106 // Ignore array length load.
2107 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) {
2108 // Ignore first AddP.
2109 } else {
2110 const Type* elemtype = adr_type->isa_aryptr()->elem();
2111 if (elemtype->isa_valuetype()) {
2112 assert(field_offset != Type::OffsetBot, "invalid field offset");
2113 ciValueKlass* vk = elemtype->is_valuetype()->value_klass();
2114 field_offset += vk->first_field_offset();
2115 bt = vk->get_field_by_offset(field_offset, false)->layout_type();
2116 } else {
2117 bt = elemtype->array_element_basic_type();
2118 }
2119 }
2120 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) {
2121 // Allocation initialization, ThreadLocal field access, unsafe access
2122 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2123 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2124 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) {
2125 bt = T_OBJECT;
2126 }
2127 }
2128 }
2129 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY);
2130 }
2131
2132 // Returns unique pointed java object or NULL.
2133 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) {
2134 assert(!_collecting, "should not call when contructed graph");
2135 // If the node was created after the escape computation we can't answer.
2136 uint idx = n->_idx;
2137 if (idx >= nodes_size()) {
2138 return NULL;
2139 }
2140 PointsToNode* ptn = ptnode_adr(idx);
2141 if (ptn->is_JavaObject()) {
2142 return ptn->as_JavaObject();
2143 }
2144 assert(ptn->is_LocalVar(), "sanity");
2145 // Check all java objects it points to.
2146 JavaObjectNode* jobj = NULL;
2147 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2148 PointsToNode* e = i.get();
2149 if (e->is_JavaObject()) {
2150 if (jobj == NULL) {
2151 jobj = e->as_JavaObject();
2152 } else if (jobj != e) {
2153 return NULL;
2154 }
2155 }
2156 }
2157 return jobj;
2158 }
2159
2160 // Return true if this node points only to non-escaping allocations.
2161 bool PointsToNode::non_escaping_allocation() {
2162 if (is_JavaObject()) {
2163 Node* n = ideal_node();
2164 if (n->is_Allocate() || n->is_CallStaticJava()) {
2165 return (escape_state() == PointsToNode::NoEscape);
2166 } else {
2167 return false;
2168 }
2169 }
2170 assert(is_LocalVar(), "sanity");
2171 // Check all java objects it points to.
2172 for (EdgeIterator i(this); i.has_next(); i.next()) {
2173 PointsToNode* e = i.get();
2174 if (e->is_JavaObject()) {
2175 Node* n = e->ideal_node();
2176 if ((e->escape_state() != PointsToNode::NoEscape) ||
2177 !(n->is_Allocate() || n->is_CallStaticJava())) {
2178 return false;
2179 }
2180 }
2181 }
2182 return true;
2183 }
2184
2185 // Return true if we know the node does not escape globally.
2186 bool ConnectionGraph::not_global_escape(Node *n) {
2187 assert(!_collecting, "should not call during graph construction");
2188 // If the node was created after the escape computation we can't answer.
2189 uint idx = n->_idx;
2190 if (idx >= nodes_size()) {
2191 return false;
2192 }
2193 PointsToNode* ptn = ptnode_adr(idx);
2194 PointsToNode::EscapeState es = ptn->escape_state();
2195 // If we have already computed a value, return it.
2196 if (es >= PointsToNode::GlobalEscape)
2197 return false;
2198 if (ptn->is_JavaObject()) {
2199 return true; // (es < PointsToNode::GlobalEscape);
2200 }
2201 assert(ptn->is_LocalVar(), "sanity");
2202 // Check all java objects it points to.
2203 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2204 if (i.get()->escape_state() >= PointsToNode::GlobalEscape)
2205 return false;
2206 }
2207 return true;
2208 }
2209
2210
2211 // Helper functions
2212
2213 // Return true if this node points to specified node or nodes it points to.
2214 bool PointsToNode::points_to(JavaObjectNode* ptn) const {
2215 if (is_JavaObject()) {
2216 return (this == ptn);
2217 }
2218 assert(is_LocalVar() || is_Field(), "sanity");
2219 for (EdgeIterator i(this); i.has_next(); i.next()) {
2220 if (i.get() == ptn)
2221 return true;
2222 }
2223 return false;
2224 }
2225
2226 // Return true if one node points to an other.
2227 bool PointsToNode::meet(PointsToNode* ptn) {
2228 if (this == ptn) {
2229 return true;
2230 } else if (ptn->is_JavaObject()) {
2231 return this->points_to(ptn->as_JavaObject());
2232 } else if (this->is_JavaObject()) {
2233 return ptn->points_to(this->as_JavaObject());
2234 }
2235 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity");
2236 int ptn_count = ptn->edge_count();
2237 for (EdgeIterator i(this); i.has_next(); i.next()) {
2238 PointsToNode* this_e = i.get();
2239 for (int j = 0; j < ptn_count; j++) {
2240 if (this_e == ptn->edge(j))
2241 return true;
2242 }
2243 }
2244 return false;
2245 }
2246
2247 #ifdef ASSERT
2248 // Return true if bases point to this java object.
2249 bool FieldNode::has_base(JavaObjectNode* jobj) const {
2250 for (BaseIterator i(this); i.has_next(); i.next()) {
2251 if (i.get() == jobj)
2252 return true;
2253 }
2254 return false;
2255 }
2256 #endif
2257
2258 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
2259 const Type *adr_type = phase->type(adr);
2260 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL &&
2261 adr->in(AddPNode::Address)->is_Proj() &&
2262 adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
2263 // We are computing a raw address for a store captured by an Initialize
2264 // compute an appropriate address type. AddP cases #3 and #5 (see below).
2265 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
2266 assert(offs != Type::OffsetBot ||
2267 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
2268 "offset must be a constant or it is initialization of array");
2269 return offs;
2270 }
2271 const TypePtr *t_ptr = adr_type->isa_ptr();
2272 assert(t_ptr != NULL, "must be a pointer type");
2273 return t_ptr->offset();
2274 }
2275
2276 Node* ConnectionGraph::get_addp_base(Node *addp) {
2277 assert(addp->is_AddP(), "must be AddP");
2278 //
2279 // AddP cases for Base and Address inputs:
2280 // case #1. Direct object's field reference:
2281 // Allocate
2282 // |
2283 // Proj #5 ( oop result )
2284 // |
2285 // CheckCastPP (cast to instance type)
2286 // | |
2287 // AddP ( base == address )
2288 //
2289 // case #2. Indirect object's field reference:
2290 // Phi
2291 // |
2292 // CastPP (cast to instance type)
2293 // | |
2294 // AddP ( base == address )
2295 //
2296 // case #3. Raw object's field reference for Initialize node:
2297 // Allocate
2298 // |
2299 // Proj #5 ( oop result )
2300 // top |
2301 // \ |
2302 // AddP ( base == top )
2303 //
2304 // case #4. Array's element reference:
2305 // {CheckCastPP | CastPP}
2306 // | | |
2307 // | AddP ( array's element offset )
2308 // | |
2309 // AddP ( array's offset )
2310 //
2311 // case #5. Raw object's field reference for arraycopy stub call:
2312 // The inline_native_clone() case when the arraycopy stub is called
2313 // after the allocation before Initialize and CheckCastPP nodes.
2314 // Allocate
2315 // |
2316 // Proj #5 ( oop result )
2317 // | |
2318 // AddP ( base == address )
2319 //
2320 // case #6. Constant Pool, ThreadLocal, CastX2P or
2321 // Raw object's field reference:
2322 // {ConP, ThreadLocal, CastX2P, raw Load}
2323 // top |
2324 // \ |
2325 // AddP ( base == top )
2326 //
2327 // case #7. Klass's field reference.
2328 // LoadKlass
2329 // | |
2330 // AddP ( base == address )
2331 //
2332 // case #8. narrow Klass's field reference.
2333 // LoadNKlass
2334 // |
2335 // DecodeN
2336 // | |
2337 // AddP ( base == address )
2338 //
2339 Node *base = addp->in(AddPNode::Base);
2340 if (base->uncast()->is_top()) { // The AddP case #3 and #6.
2341 base = addp->in(AddPNode::Address);
2342 while (base->is_AddP()) {
2343 // Case #6 (unsafe access) may have several chained AddP nodes.
2344 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only");
2345 base = base->in(AddPNode::Address);
2346 }
2347 Node* uncast_base = base->uncast();
2348 int opcode = uncast_base->Opcode();
2349 assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
2350 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
2351 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) ||
2352 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity");
2353 }
2354 return base;
2355 }
2356
2357 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) {
2358 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
2359 Node* addp2 = addp->raw_out(0);
2360 if (addp->outcnt() == 1 && addp2->is_AddP() &&
2361 addp2->in(AddPNode::Base) == n &&
2362 addp2->in(AddPNode::Address) == addp) {
2363 assert(addp->in(AddPNode::Base) == n, "expecting the same base");
2364 //
2365 // Find array's offset to push it on worklist first and
2366 // as result process an array's element offset first (pushed second)
2367 // to avoid CastPP for the array's offset.
2368 // Otherwise the inserted CastPP (LocalVar) will point to what
2369 // the AddP (Field) points to. Which would be wrong since
2370 // the algorithm expects the CastPP has the same point as
2371 // as AddP's base CheckCastPP (LocalVar).
2372 //
2373 // ArrayAllocation
2374 // |
2375 // CheckCastPP
2376 // |
2377 // memProj (from ArrayAllocation CheckCastPP)
2378 // | ||
2379 // | || Int (element index)
2380 // | || | ConI (log(element size))
2381 // | || | /
2382 // | || LShift
2383 // | || /
2384 // | AddP (array's element offset)
2385 // | |
2386 // | | ConI (array's offset: #12(32-bits) or #24(64-bits))
2387 // | / /
2388 // AddP (array's offset)
2389 // |
2390 // Load/Store (memory operation on array's element)
2391 //
2392 return addp2;
2393 }
2394 return NULL;
2395 }
2396
2397 //
2398 // Adjust the type and inputs of an AddP which computes the
2399 // address of a field of an instance
2400 //
2401 bool ConnectionGraph::split_AddP(Node *addp, Node *base) {
2402 PhaseGVN* igvn = _igvn;
2403 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
2404 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
2405 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
2406 if (t == NULL) {
2407 // We are computing a raw address for a store captured by an Initialize
2408 // compute an appropriate address type (cases #3 and #5).
2409 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
2410 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
2411 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
2412 assert(offs != Type::OffsetBot, "offset must be a constant");
2413 t = base_t->add_offset(offs)->is_oopptr();
2414 }
2415 int inst_id = base_t->instance_id();
2416 assert(!t->is_known_instance() || t->instance_id() == inst_id,
2417 "old type must be non-instance or match new type");
2418
2419 // The type 't' could be subclass of 'base_t'.
2420 // As result t->offset() could be large then base_t's size and it will
2421 // cause the failure in add_offset() with narrow oops since TypeOopPtr()
2422 // constructor verifies correctness of the offset.
2423 //
2424 // It could happened on subclass's branch (from the type profiling
2425 // inlining) which was not eliminated during parsing since the exactness
2426 // of the allocation type was not propagated to the subclass type check.
2427 //
2428 // Or the type 't' could be not related to 'base_t' at all.
2429 // It could happened when CHA type is different from MDO type on a dead path
2430 // (for example, from instanceof check) which is not collapsed during parsing.
2431 //
2432 // Do nothing for such AddP node and don't process its users since
2433 // this code branch will go away.
2434 //
2435 if (!t->is_known_instance() &&
2436 !base_t->klass()->is_subtype_of(t->klass())) {
2437 return false; // bail out
2438 }
2439 const TypePtr* tinst = base_t->add_offset(t->offset());
2440 if (tinst->isa_aryptr() && t->isa_aryptr()) {
2441 // In the case of a flattened value type array, each field has its
2442 // own slice so we need to keep track of the field being accessed.
2443 tinst = tinst->is_aryptr()->with_field_offset(t->is_aryptr()->field_offset().get());
2444 }
2445
2446 // Do NOT remove the next line: ensure a new alias index is allocated
2447 // for the instance type. Note: C++ will not remove it since the call
2448 // has side effect.
2449 int alias_idx = _compile->get_alias_index(tinst);
2450 igvn->set_type(addp, tinst);
2451 // record the allocation in the node map
2452 set_map(addp, get_map(base->_idx));
2453 // Set addp's Base and Address to 'base'.
2454 Node *abase = addp->in(AddPNode::Base);
2455 Node *adr = addp->in(AddPNode::Address);
2456 if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
2457 adr->in(0)->_idx == (uint)inst_id) {
2458 // Skip AddP cases #3 and #5.
2459 } else {
2460 assert(!abase->is_top(), "sanity"); // AddP case #3
2461 if (abase != base) {
2462 igvn->hash_delete(addp);
2463 addp->set_req(AddPNode::Base, base);
2464 if (abase == adr) {
2465 addp->set_req(AddPNode::Address, base);
2466 } else {
2467 // AddP case #4 (adr is array's element offset AddP node)
2468 #ifdef ASSERT
2469 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
2470 assert(adr->is_AddP() && atype != NULL &&
2471 atype->instance_id() == inst_id, "array's element offset should be processed first");
2472 #endif
2473 }
2474 igvn->hash_insert(addp);
2475 }
2476 }
2477 // Put on IGVN worklist since at least addp's type was changed above.
2478 record_for_optimizer(addp);
2479 return true;
2480 }
2481
2482 //
2483 // Create a new version of orig_phi if necessary. Returns either the newly
2484 // created phi or an existing phi. Sets create_new to indicate whether a new
2485 // phi was created. Cache the last newly created phi in the node map.
2486 //
2487 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) {
2488 Compile *C = _compile;
2489 PhaseGVN* igvn = _igvn;
2490 new_created = false;
2491 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
2492 // nothing to do if orig_phi is bottom memory or matches alias_idx
2493 if (phi_alias_idx == alias_idx) {
2494 return orig_phi;
2495 }
2496 // Have we recently created a Phi for this alias index?
2497 PhiNode *result = get_map_phi(orig_phi->_idx);
2498 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
2499 return result;
2500 }
2501 // Previous check may fail when the same wide memory Phi was split into Phis
2502 // for different memory slices. Search all Phis for this region.
2503 if (result != NULL) {
2504 Node* region = orig_phi->in(0);
2505 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2506 Node* phi = region->fast_out(i);
2507 if (phi->is_Phi() &&
2508 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
2509 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
2510 return phi->as_Phi();
2511 }
2512 }
2513 }
2514 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) {
2515 if (C->do_escape_analysis() == true && !C->failing()) {
2516 // Retry compilation without escape analysis.
2517 // If this is the first failure, the sentinel string will "stick"
2518 // to the Compile object, and the C2Compiler will see it and retry.
2519 C->record_failure(C2Compiler::retry_no_escape_analysis());
2520 }
2521 return NULL;
2522 }
2523 orig_phi_worklist.append_if_missing(orig_phi);
2524 const TypePtr *atype = C->get_adr_type(alias_idx);
2525 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
2526 C->copy_node_notes_to(result, orig_phi);
2527 igvn->set_type(result, result->bottom_type());
2528 record_for_optimizer(result);
2529 set_map(orig_phi, result);
2530 new_created = true;
2531 return result;
2532 }
2533
2534 //
2535 // Return a new version of Memory Phi "orig_phi" with the inputs having the
2536 // specified alias index.
2537 //
2538 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) {
2539 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
2540 Compile *C = _compile;
2541 PhaseGVN* igvn = _igvn;
2542 bool new_phi_created;
2543 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created);
2544 if (!new_phi_created) {
2545 return result;
2546 }
2547 GrowableArray<PhiNode *> phi_list;
2548 GrowableArray<uint> cur_input;
2549 PhiNode *phi = orig_phi;
2550 uint idx = 1;
2551 bool finished = false;
2552 while(!finished) {
2553 while (idx < phi->req()) {
2554 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist);
2555 if (mem != NULL && mem->is_Phi()) {
2556 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created);
2557 if (new_phi_created) {
2558 // found an phi for which we created a new split, push current one on worklist and begin
2559 // processing new one
2560 phi_list.push(phi);
2561 cur_input.push(idx);
2562 phi = mem->as_Phi();
2563 result = newphi;
2564 idx = 1;
2565 continue;
2566 } else {
2567 mem = newphi;
2568 }
2569 }
2570 if (C->failing()) {
2571 return NULL;
2572 }
2573 result->set_req(idx++, mem);
2574 }
2575 #ifdef ASSERT
2576 // verify that the new Phi has an input for each input of the original
2577 assert( phi->req() == result->req(), "must have same number of inputs.");
2578 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
2579 #endif
2580 // Check if all new phi's inputs have specified alias index.
2581 // Otherwise use old phi.
2582 for (uint i = 1; i < phi->req(); i++) {
2583 Node* in = result->in(i);
2584 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
2585 }
2586 // we have finished processing a Phi, see if there are any more to do
2587 finished = (phi_list.length() == 0 );
2588 if (!finished) {
2589 phi = phi_list.pop();
2590 idx = cur_input.pop();
2591 PhiNode *prev_result = get_map_phi(phi->_idx);
2592 prev_result->set_req(idx++, result);
2593 result = prev_result;
2594 }
2595 }
2596 return result;
2597 }
2598
2599 //
2600 // The next methods are derived from methods in MemNode.
2601 //
2602 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
2603 Node *mem = mmem;
2604 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
2605 // means an array I have not precisely typed yet. Do not do any
2606 // alias stuff with it any time soon.
2607 if (toop->base() != Type::AnyPtr &&
2608 !(toop->klass() != NULL &&
2609 toop->klass()->is_java_lang_Object() &&
2610 toop->offset() == Type::OffsetBot)) {
2611 mem = mmem->memory_at(alias_idx);
2612 // Update input if it is progress over what we have now
2613 }
2614 return mem;
2615 }
2616
2617 //
2618 // Move memory users to their memory slices.
2619 //
2620 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) {
2621 Compile* C = _compile;
2622 PhaseGVN* igvn = _igvn;
2623 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
2624 assert(tp != NULL, "ptr type");
2625 int alias_idx = C->get_alias_index(tp);
2626 int general_idx = C->get_general_index(alias_idx);
2627
2628 // Move users first
2629 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2630 Node* use = n->fast_out(i);
2631 if (use->is_MergeMem()) {
2632 MergeMemNode* mmem = use->as_MergeMem();
2633 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
2634 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
2635 continue; // Nothing to do
2636 }
2637 // Replace previous general reference to mem node.
2638 uint orig_uniq = C->unique();
2639 Node* m = find_inst_mem(n, general_idx, orig_phis);
2640 assert(orig_uniq == C->unique(), "no new nodes");
2641 mmem->set_memory_at(general_idx, m);
2642 --imax;
2643 --i;
2644 } else if (use->is_MemBar()) {
2645 assert(!use->is_Initialize(), "initializing stores should not be moved");
2646 if (use->req() > MemBarNode::Precedent &&
2647 use->in(MemBarNode::Precedent) == n) {
2648 // Don't move related membars.
2649 record_for_optimizer(use);
2650 continue;
2651 }
2652 tp = use->as_MemBar()->adr_type()->isa_ptr();
2653 if (tp != NULL && C->get_alias_index(tp) == alias_idx ||
2654 alias_idx == general_idx) {
2655 continue; // Nothing to do
2656 }
2657 // Move to general memory slice.
2658 uint orig_uniq = C->unique();
2659 Node* m = find_inst_mem(n, general_idx, orig_phis);
2660 assert(orig_uniq == C->unique(), "no new nodes");
2661 igvn->hash_delete(use);
2662 imax -= use->replace_edge(n, m);
2663 igvn->hash_insert(use);
2664 record_for_optimizer(use);
2665 --i;
2666 #ifdef ASSERT
2667 } else if (use->is_Mem()) {
2668 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) {
2669 // Don't move related cardmark.
2670 continue;
2671 }
2672 // Memory nodes should have new memory input.
2673 tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
2674 assert(tp != NULL, "ptr type");
2675 int idx = C->get_alias_index(tp);
2676 assert(get_map(use->_idx) != NULL || idx == alias_idx,
2677 "Following memory nodes should have new memory input or be on the same memory slice");
2678 } else if (use->is_Phi()) {
2679 // Phi nodes should be split and moved already.
2680 tp = use->as_Phi()->adr_type()->isa_ptr();
2681 assert(tp != NULL, "ptr type");
2682 int idx = C->get_alias_index(tp);
2683 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
2684 } else {
2685 use->dump();
2686 assert(false, "should not be here");
2687 #endif
2688 }
2689 }
2690 }
2691
2692 //
2693 // Search memory chain of "mem" to find a MemNode whose address
2694 // is the specified alias index.
2695 //
2696 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) {
2697 if (orig_mem == NULL)
2698 return orig_mem;
2699 Compile* C = _compile;
2700 PhaseGVN* igvn = _igvn;
2701 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
2702 bool is_instance = (toop != NULL) && toop->is_known_instance();
2703 Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
2704 Node *prev = NULL;
2705 Node *result = orig_mem;
2706 while (prev != result) {
2707 prev = result;
2708 if (result == start_mem)
2709 break; // hit one of our sentinels
2710 if (result->is_Mem()) {
2711 const Type *at = igvn->type(result->in(MemNode::Address));
2712 if (at == Type::TOP)
2713 break; // Dead
2714 assert (at->isa_ptr() != NULL, "pointer type required.");
2715 int idx = C->get_alias_index(at->is_ptr());
2716 if (idx == alias_idx)
2717 break; // Found
2718 if (!is_instance && (at->isa_oopptr() == NULL ||
2719 !at->is_oopptr()->is_known_instance())) {
2720 break; // Do not skip store to general memory slice.
2721 }
2722 result = result->in(MemNode::Memory);
2723 }
2724 if (!is_instance)
2725 continue; // don't search further for non-instance types
2726 // skip over a call which does not affect this memory slice
2727 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
2728 Node *proj_in = result->in(0);
2729 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
2730 break; // hit one of our sentinels
2731 } else if (proj_in->is_Call()) {
2732 // ArrayCopy node processed here as well
2733 CallNode *call = proj_in->as_Call();
2734 if (!call->may_modify(toop, igvn)) {
2735 result = call->in(TypeFunc::Memory);
2736 }
2737 } else if (proj_in->is_Initialize()) {
2738 AllocateNode* alloc = proj_in->as_Initialize()->allocation();
2739 // Stop if this is the initialization for the object instance which
2740 // which contains this memory slice, otherwise skip over it.
2741 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) {
2742 result = proj_in->in(TypeFunc::Memory);
2743 }
2744 } else if (proj_in->is_MemBar()) {
2745 if (proj_in->in(TypeFunc::Memory)->is_MergeMem() &&
2746 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->is_Proj() &&
2747 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->is_ArrayCopy()) {
2748 // clone
2749 ArrayCopyNode* ac = proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->as_ArrayCopy();
2750 if (ac->may_modify(toop, igvn)) {
2751 break;
2752 }
2753 }
2754 result = proj_in->in(TypeFunc::Memory);
2755 }
2756 } else if (result->is_MergeMem()) {
2757 MergeMemNode *mmem = result->as_MergeMem();
2758 result = step_through_mergemem(mmem, alias_idx, toop);
2759 if (result == mmem->base_memory()) {
2760 // Didn't find instance memory, search through general slice recursively.
2761 result = mmem->memory_at(C->get_general_index(alias_idx));
2762 result = find_inst_mem(result, alias_idx, orig_phis);
2763 if (C->failing()) {
2764 return NULL;
2765 }
2766 mmem->set_memory_at(alias_idx, result);
2767 }
2768 } else if (result->is_Phi() &&
2769 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
2770 Node *un = result->as_Phi()->unique_input(igvn);
2771 if (un != NULL) {
2772 orig_phis.append_if_missing(result->as_Phi());
2773 result = un;
2774 } else {
2775 break;
2776 }
2777 } else if (result->is_ClearArray()) {
2778 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) {
2779 // Can not bypass initialization of the instance
2780 // we are looking for.
2781 break;
2782 }
2783 // Otherwise skip it (the call updated 'result' value).
2784 } else if (result->Opcode() == Op_SCMemProj) {
2785 Node* mem = result->in(0);
2786 Node* adr = NULL;
2787 if (mem->is_LoadStore()) {
2788 adr = mem->in(MemNode::Address);
2789 } else {
2790 assert(mem->Opcode() == Op_EncodeISOArray ||
2791 mem->Opcode() == Op_StrCompressedCopy, "sanity");
2792 adr = mem->in(3); // Memory edge corresponds to destination array
2793 }
2794 const Type *at = igvn->type(adr);
2795 if (at != Type::TOP) {
2796 assert(at->isa_ptr() != NULL, "pointer type required.");
2797 int idx = C->get_alias_index(at->is_ptr());
2798 if (idx == alias_idx) {
2799 // Assert in debug mode
2800 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
2801 break; // In product mode return SCMemProj node
2802 }
2803 }
2804 result = mem->in(MemNode::Memory);
2805 } else if (result->Opcode() == Op_StrInflatedCopy) {
2806 Node* adr = result->in(3); // Memory edge corresponds to destination array
2807 const Type *at = igvn->type(adr);
2808 if (at != Type::TOP) {
2809 assert(at->isa_ptr() != NULL, "pointer type required.");
2810 int idx = C->get_alias_index(at->is_ptr());
2811 if (idx == alias_idx) {
2812 // Assert in debug mode
2813 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
2814 break; // In product mode return SCMemProj node
2815 }
2816 }
2817 result = result->in(MemNode::Memory);
2818 }
2819 }
2820 if (result->is_Phi()) {
2821 PhiNode *mphi = result->as_Phi();
2822 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
2823 const TypePtr *t = mphi->adr_type();
2824 if (!is_instance) {
2825 // Push all non-instance Phis on the orig_phis worklist to update inputs
2826 // during Phase 4 if needed.
2827 orig_phis.append_if_missing(mphi);
2828 } else if (C->get_alias_index(t) != alias_idx) {
2829 // Create a new Phi with the specified alias index type.
2830 result = split_memory_phi(mphi, alias_idx, orig_phis);
2831 }
2832 }
2833 // the result is either MemNode, PhiNode, InitializeNode.
2834 return result;
2835 }
2836
2837 //
2838 // Convert the types of unescaped object to instance types where possible,
2839 // propagate the new type information through the graph, and update memory
2840 // edges and MergeMem inputs to reflect the new type.
2841 //
2842 // We start with allocations (and calls which may be allocations) on alloc_worklist.
2843 // The processing is done in 4 phases:
2844 //
2845 // Phase 1: Process possible allocations from alloc_worklist. Create instance
2846 // types for the CheckCastPP for allocations where possible.
2847 // Propagate the new types through users as follows:
2848 // casts and Phi: push users on alloc_worklist
2849 // AddP: cast Base and Address inputs to the instance type
2850 // push any AddP users on alloc_worklist and push any memnode
2851 // users onto memnode_worklist.
2852 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
2853 // search the Memory chain for a store with the appropriate type
2854 // address type. If a Phi is found, create a new version with
2855 // the appropriate memory slices from each of the Phi inputs.
2856 // For stores, process the users as follows:
2857 // MemNode: push on memnode_worklist
2858 // MergeMem: push on mergemem_worklist
2859 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
2860 // moving the first node encountered of each instance type to the
2861 // the input corresponding to its alias index.
2862 // appropriate memory slice.
2863 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
2864 //
2865 // In the following example, the CheckCastPP nodes are the cast of allocation
2866 // results and the allocation of node 29 is unescaped and eligible to be an
2867 // instance type.
2868 //
2869 // We start with:
2870 //
2871 // 7 Parm #memory
2872 // 10 ConI "12"
2873 // 19 CheckCastPP "Foo"
2874 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2875 // 29 CheckCastPP "Foo"
2876 // 30 AddP _ 29 29 10 Foo+12 alias_index=4
2877 //
2878 // 40 StoreP 25 7 20 ... alias_index=4
2879 // 50 StoreP 35 40 30 ... alias_index=4
2880 // 60 StoreP 45 50 20 ... alias_index=4
2881 // 70 LoadP _ 60 30 ... alias_index=4
2882 // 80 Phi 75 50 60 Memory alias_index=4
2883 // 90 LoadP _ 80 30 ... alias_index=4
2884 // 100 LoadP _ 80 20 ... alias_index=4
2885 //
2886 //
2887 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
2888 // and creating a new alias index for node 30. This gives:
2889 //
2890 // 7 Parm #memory
2891 // 10 ConI "12"
2892 // 19 CheckCastPP "Foo"
2893 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2894 // 29 CheckCastPP "Foo" iid=24
2895 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
2896 //
2897 // 40 StoreP 25 7 20 ... alias_index=4
2898 // 50 StoreP 35 40 30 ... alias_index=6
2899 // 60 StoreP 45 50 20 ... alias_index=4
2900 // 70 LoadP _ 60 30 ... alias_index=6
2901 // 80 Phi 75 50 60 Memory alias_index=4
2902 // 90 LoadP _ 80 30 ... alias_index=6
2903 // 100 LoadP _ 80 20 ... alias_index=4
2904 //
2905 // In phase 2, new memory inputs are computed for the loads and stores,
2906 // And a new version of the phi is created. In phase 4, the inputs to
2907 // node 80 are updated and then the memory nodes are updated with the
2908 // values computed in phase 2. This results in:
2909 //
2910 // 7 Parm #memory
2911 // 10 ConI "12"
2912 // 19 CheckCastPP "Foo"
2913 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2914 // 29 CheckCastPP "Foo" iid=24
2915 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
2916 //
2917 // 40 StoreP 25 7 20 ... alias_index=4
2918 // 50 StoreP 35 7 30 ... alias_index=6
2919 // 60 StoreP 45 40 20 ... alias_index=4
2920 // 70 LoadP _ 50 30 ... alias_index=6
2921 // 80 Phi 75 40 60 Memory alias_index=4
2922 // 120 Phi 75 50 50 Memory alias_index=6
2923 // 90 LoadP _ 120 30 ... alias_index=6
2924 // 100 LoadP _ 80 20 ... alias_index=4
2925 //
2926 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist, GrowableArray<ArrayCopyNode*> &arraycopy_worklist) {
2927 GrowableArray<Node *> memnode_worklist;
2928 GrowableArray<PhiNode *> orig_phis;
2929 PhaseIterGVN *igvn = _igvn;
2930 uint new_index_start = (uint) _compile->num_alias_types();
2931 Arena* arena = Thread::current()->resource_area();
2932 VectorSet visited(arena);
2933 ideal_nodes.clear(); // Reset for use with set_map/get_map.
2934 uint unique_old = _compile->unique();
2935
2936 // Phase 1: Process possible allocations from alloc_worklist.
2937 // Create instance types for the CheckCastPP for allocations where possible.
2938 //
2939 // (Note: don't forget to change the order of the second AddP node on
2940 // the alloc_worklist if the order of the worklist processing is changed,
2941 // see the comment in find_second_addp().)
2942 //
2943 while (alloc_worklist.length() != 0) {
2944 Node *n = alloc_worklist.pop();
2945 uint ni = n->_idx;
2946 if (n->is_Call()) {
2947 CallNode *alloc = n->as_Call();
2948 // copy escape information to call node
2949 PointsToNode* ptn = ptnode_adr(alloc->_idx);
2950 PointsToNode::EscapeState es = ptn->escape_state();
2951 // We have an allocation or call which returns a Java object,
2952 // see if it is unescaped.
2953 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable())
2954 continue;
2955 // Find CheckCastPP for the allocate or for the return value of a call
2956 n = alloc->result_cast();
2957 if (n == NULL) { // No uses except Initialize node
2958 if (alloc->is_Allocate()) {
2959 // Set the scalar_replaceable flag for allocation
2960 // so it could be eliminated if it has no uses.
2961 alloc->as_Allocate()->_is_scalar_replaceable = true;
2962 }
2963 if (alloc->is_CallStaticJava()) {
2964 // Set the scalar_replaceable flag for boxing method
2965 // so it could be eliminated if it has no uses.
2966 alloc->as_CallStaticJava()->_is_scalar_replaceable = true;
2967 }
2968 continue;
2969 }
2970 if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
2971 assert(!alloc->is_Allocate(), "allocation should have unique type");
2972 continue;
2973 }
2974
2975 // The inline code for Object.clone() casts the allocation result to
2976 // java.lang.Object and then to the actual type of the allocated
2977 // object. Detect this case and use the second cast.
2978 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
2979 // the allocation result is cast to java.lang.Object and then
2980 // to the actual Array type.
2981 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
2982 && (alloc->is_AllocateArray() ||
2983 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
2984 Node *cast2 = NULL;
2985 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2986 Node *use = n->fast_out(i);
2987 if (use->is_CheckCastPP()) {
2988 cast2 = use;
2989 break;
2990 }
2991 }
2992 if (cast2 != NULL) {
2993 n = cast2;
2994 } else {
2995 // Non-scalar replaceable if the allocation type is unknown statically
2996 // (reflection allocation), the object can't be restored during
2997 // deoptimization without precise type.
2998 continue;
2999 }
3000 }
3001
3002 const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
3003 if (t == NULL)
3004 continue; // not a TypeOopPtr
3005 if (!t->klass_is_exact())
3006 continue; // not an unique type
3007
3008 if (alloc->is_Allocate()) {
3009 // Set the scalar_replaceable flag for allocation
3010 // so it could be eliminated.
3011 alloc->as_Allocate()->_is_scalar_replaceable = true;
3012 }
3013 if (alloc->is_CallStaticJava()) {
3014 // Set the scalar_replaceable flag for boxing method
3015 // so it could be eliminated.
3016 alloc->as_CallStaticJava()->_is_scalar_replaceable = true;
3017 }
3018 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state
3019 // in order for an object to be scalar-replaceable, it must be:
3020 // - a direct allocation (not a call returning an object)
3021 // - non-escaping
3022 // - eligible to be a unique type
3023 // - not determined to be ineligible by escape analysis
3024 set_map(alloc, n);
3025 set_map(n, alloc);
3026 const TypeOopPtr* tinst = t->cast_to_instance_id(ni);
3027 igvn->hash_delete(n);
3028 igvn->set_type(n, tinst);
3029 n->raise_bottom_type(tinst);
3030 igvn->hash_insert(n);
3031 record_for_optimizer(n);
3032 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr() || t->isa_valuetypeptr())) {
3033
3034 // First, put on the worklist all Field edges from Connection Graph
3035 // which is more accurate than putting immediate users from Ideal Graph.
3036 for (EdgeIterator e(ptn); e.has_next(); e.next()) {
3037 PointsToNode* tgt = e.get();
3038 if (tgt->is_Arraycopy()) {
3039 continue;
3040 }
3041 Node* use = tgt->ideal_node();
3042 assert(tgt->is_Field() && use->is_AddP(),
3043 "only AddP nodes are Field edges in CG");
3044 if (use->outcnt() > 0) { // Don't process dead nodes
3045 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
3046 if (addp2 != NULL) {
3047 assert(alloc->is_AllocateArray(),"array allocation was expected");
3048 alloc_worklist.append_if_missing(addp2);
3049 }
3050 alloc_worklist.append_if_missing(use);
3051 }
3052 }
3053
3054 // An allocation may have an Initialize which has raw stores. Scan
3055 // the users of the raw allocation result and push AddP users
3056 // on alloc_worklist.
3057 Node *raw_result = alloc->proj_out(TypeFunc::Parms);
3058 assert (raw_result != NULL, "must have an allocation result");
3059 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
3060 Node *use = raw_result->fast_out(i);
3061 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
3062 Node* addp2 = find_second_addp(use, raw_result);
3063 if (addp2 != NULL) {
3064 assert(alloc->is_AllocateArray(),"array allocation was expected");
3065 alloc_worklist.append_if_missing(addp2);
3066 }
3067 alloc_worklist.append_if_missing(use);
3068 } else if (use->is_MemBar()) {
3069 memnode_worklist.append_if_missing(use);
3070 }
3071 }
3072 }
3073 } else if (n->is_AddP()) {
3074 JavaObjectNode* jobj = unique_java_object(get_addp_base(n));
3075 if (jobj == NULL || jobj == phantom_obj) {
3076 #ifdef ASSERT
3077 ptnode_adr(get_addp_base(n)->_idx)->dump();
3078 ptnode_adr(n->_idx)->dump();
3079 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3080 #endif
3081 _compile->record_failure(C2Compiler::retry_no_escape_analysis());
3082 return;
3083 }
3084 Node *base = get_map(jobj->idx()); // CheckCastPP node
3085 if (!split_AddP(n, base)) continue; // wrong type from dead path
3086 } else if (n->is_Phi() ||
3087 n->is_CheckCastPP() ||
3088 n->is_EncodeP() ||
3089 n->is_DecodeN() ||
3090 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
3091 if (visited.test_set(n->_idx)) {
3092 assert(n->is_Phi(), "loops only through Phi's");
3093 continue; // already processed
3094 }
3095 JavaObjectNode* jobj = unique_java_object(n);
3096 if (jobj == NULL || jobj == phantom_obj) {
3097 #ifdef ASSERT
3098 ptnode_adr(n->_idx)->dump();
3099 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3100 #endif
3101 _compile->record_failure(C2Compiler::retry_no_escape_analysis());
3102 return;
3103 } else {
3104 Node *val = get_map(jobj->idx()); // CheckCastPP node
3105 TypeNode *tn = n->as_Type();
3106 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr();
3107 assert(tinst != NULL && tinst->is_known_instance() &&
3108 tinst->instance_id() == jobj->idx() , "instance type expected.");
3109
3110 const Type *tn_type = igvn->type(tn);
3111 const TypeOopPtr *tn_t;
3112 if (tn_type->isa_narrowoop()) {
3113 tn_t = tn_type->make_ptr()->isa_oopptr();
3114 } else {
3115 tn_t = tn_type->isa_oopptr();
3116 }
3117 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) {
3118 if (tn_type->isa_narrowoop()) {
3119 tn_type = tinst->make_narrowoop();
3120 } else {
3121 tn_type = tinst;
3122 }
3123 igvn->hash_delete(tn);
3124 igvn->set_type(tn, tn_type);
3125 tn->set_type(tn_type);
3126 igvn->hash_insert(tn);
3127 record_for_optimizer(n);
3128 } else {
3129 assert(tn_type == TypePtr::NULL_PTR ||
3130 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()),
3131 "unexpected type");
3132 continue; // Skip dead path with different type
3133 }
3134 }
3135 } else {
3136 debug_only(n->dump();)
3137 assert(false, "EA: unexpected node");
3138 continue;
3139 }
3140 // push allocation's users on appropriate worklist
3141 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3142 Node *use = n->fast_out(i);
3143 if(use->is_Mem() && use->in(MemNode::Address) == n) {
3144 // Load/store to instance's field
3145 memnode_worklist.append_if_missing(use);
3146 } else if (use->is_MemBar()) {
3147 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3148 memnode_worklist.append_if_missing(use);
3149 }
3150 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
3151 Node* addp2 = find_second_addp(use, n);
3152 if (addp2 != NULL) {
3153 alloc_worklist.append_if_missing(addp2);
3154 }
3155 alloc_worklist.append_if_missing(use);
3156 } else if (use->is_Phi() ||
3157 use->is_CheckCastPP() ||
3158 use->is_EncodeNarrowPtr() ||
3159 use->is_DecodeNarrowPtr() ||
3160 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
3161 alloc_worklist.append_if_missing(use);
3162 #ifdef ASSERT
3163 } else if (use->is_Mem()) {
3164 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
3165 } else if (use->is_MergeMem()) {
3166 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3167 } else if (use->is_SafePoint()) {
3168 // Look for MergeMem nodes for calls which reference unique allocation
3169 // (through CheckCastPP nodes) even for debug info.
3170 Node* m = use->in(TypeFunc::Memory);
3171 if (m->is_MergeMem()) {
3172 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3173 }
3174 } else if (use->Opcode() == Op_EncodeISOArray) {
3175 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3176 // EncodeISOArray overwrites destination array
3177 memnode_worklist.append_if_missing(use);
3178 }
3179 } else if (use->Opcode() == Op_Return) {
3180 Node* klass = use->in(TypeFunc::Parms);
3181 const TypeKlassPtr* tkls = igvn->type(klass)->isa_klassptr();
3182 ciValueKlass* vk = tkls->klass()->as_value_klass();
3183 assert(_compile->tf()->returns_value_type_as_fields(), "must return a value type");
3184 assert(vk->contains_oops(), "returned value type must contain a reference field");
3185 } else {
3186 uint op = use->Opcode();
3187 if ((op == Op_StrCompressedCopy || op == Op_StrInflatedCopy) &&
3188 (use->in(MemNode::Memory) == n)) {
3189 // They overwrite memory edge corresponding to destination array,
3190 memnode_worklist.append_if_missing(use);
3191 } else if (!(op == Op_CmpP || op == Op_Conv2B ||
3192 op == Op_CastP2X || op == Op_StoreCM ||
3193 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives ||
3194 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3195 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar ||
3196 op == Op_ValueType)) {
3197 n->dump();
3198 use->dump();
3199 assert(false, "EA: missing allocation reference path");
3200 }
3201 #endif
3202 }
3203 }
3204
3205 }
3206
3207 // Go over all ArrayCopy nodes and if one of the inputs has a unique
3208 // type, record it in the ArrayCopy node so we know what memory this
3209 // node uses/modified.
3210 for (int next = 0; next < arraycopy_worklist.length(); next++) {
3211 ArrayCopyNode* ac = arraycopy_worklist.at(next);
3212 Node* dest = ac->in(ArrayCopyNode::Dest);
3213 if (dest->is_AddP()) {
3214 dest = get_addp_base(dest);
3215 }
3216 JavaObjectNode* jobj = unique_java_object(dest);
3217 if (jobj != NULL) {
3218 Node *base = get_map(jobj->idx());
3219 if (base != NULL) {
3220 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3221 ac->_dest_type = base_t;
3222 }
3223 }
3224 Node* src = ac->in(ArrayCopyNode::Src);
3225 if (src->is_AddP()) {
3226 src = get_addp_base(src);
3227 }
3228 jobj = unique_java_object(src);
3229 if (jobj != NULL) {
3230 Node* base = get_map(jobj->idx());
3231 if (base != NULL) {
3232 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3233 ac->_src_type = base_t;
3234 }
3235 }
3236 }
3237
3238 // New alias types were created in split_AddP().
3239 uint new_index_end = (uint) _compile->num_alias_types();
3240 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1");
3241
3242 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
3243 // compute new values for Memory inputs (the Memory inputs are not
3244 // actually updated until phase 4.)
3245 if (memnode_worklist.length() == 0)
3246 return; // nothing to do
3247 while (memnode_worklist.length() != 0) {
3248 Node *n = memnode_worklist.pop();
3249 if (visited.test_set(n->_idx))
3250 continue;
3251 if (n->is_Phi() || n->is_ClearArray()) {
3252 // we don't need to do anything, but the users must be pushed
3253 } else if (n->is_MemBar()) { // Initialize, MemBar nodes
3254 // we don't need to do anything, but the users must be pushed
3255 n = n->as_MemBar()->proj_out(TypeFunc::Memory);
3256 if (n == NULL)
3257 continue;
3258 } else if (n->Opcode() == Op_StrCompressedCopy ||
3259 n->Opcode() == Op_EncodeISOArray) {
3260 // get the memory projection
3261 n = n->find_out_with(Op_SCMemProj);
3262 assert(n->Opcode() == Op_SCMemProj, "memory projection required");
3263 } else {
3264 assert(n->is_Mem(), "memory node required.");
3265 Node *addr = n->in(MemNode::Address);
3266 const Type *addr_t = igvn->type(addr);
3267 if (addr_t == Type::TOP)
3268 continue;
3269 assert (addr_t->isa_ptr() != NULL, "pointer type required.");
3270 int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
3271 assert ((uint)alias_idx < new_index_end, "wrong alias index");
3272 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis);
3273 if (_compile->failing()) {
3274 return;
3275 }
3276 if (mem != n->in(MemNode::Memory)) {
3277 // We delay the memory edge update since we need old one in
3278 // MergeMem code below when instances memory slices are separated.
3279 set_map(n, mem);
3280 }
3281 if (n->is_Load()) {
3282 continue; // don't push users
3283 } else if (n->is_LoadStore()) {
3284 // get the memory projection
3285 n = n->find_out_with(Op_SCMemProj);
3286 assert(n->Opcode() == Op_SCMemProj, "memory projection required");
3287 }
3288 }
3289 // push user on appropriate worklist
3290 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3291 Node *use = n->fast_out(i);
3292 if (use->is_Phi() || use->is_ClearArray()) {
3293 memnode_worklist.append_if_missing(use);
3294 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) {
3295 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores
3296 continue;
3297 memnode_worklist.append_if_missing(use);
3298 } else if (use->is_MemBar()) {
3299 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3300 memnode_worklist.append_if_missing(use);
3301 }
3302 #ifdef ASSERT
3303 } else if(use->is_Mem()) {
3304 assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
3305 } else if (use->is_MergeMem()) {
3306 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3307 } else if (use->Opcode() == Op_EncodeISOArray) {
3308 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3309 // EncodeISOArray overwrites destination array
3310 memnode_worklist.append_if_missing(use);
3311 }
3312 } else {
3313 uint op = use->Opcode();
3314 if ((use->in(MemNode::Memory) == n) &&
3315 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) {
3316 // They overwrite memory edge corresponding to destination array,
3317 memnode_worklist.append_if_missing(use);
3318 } else if (!(op == Op_StoreCM ||
3319 (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL &&
3320 strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) ||
3321 op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives ||
3322 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3323 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) {
3324 n->dump();
3325 use->dump();
3326 assert(false, "EA: missing memory path");
3327 }
3328 #endif
3329 }
3330 }
3331 }
3332
3333 // Phase 3: Process MergeMem nodes from mergemem_worklist.
3334 // Walk each memory slice moving the first node encountered of each
3335 // instance type to the input corresponding to its alias index.
3336 uint length = _mergemem_worklist.length();
3337 for( uint next = 0; next < length; ++next ) {
3338 MergeMemNode* nmm = _mergemem_worklist.at(next);
3339 assert(!visited.test_set(nmm->_idx), "should not be visited before");
3340 // Note: we don't want to use MergeMemStream here because we only want to
3341 // scan inputs which exist at the start, not ones we add during processing.
3342 // Note 2: MergeMem may already contains instance memory slices added
3343 // during find_inst_mem() call when memory nodes were processed above.
3344 igvn->hash_delete(nmm);
3345 uint nslices = MIN2(nmm->req(), new_index_start);
3346 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
3347 Node* mem = nmm->in(i);
3348 Node* cur = NULL;
3349 if (mem == NULL || mem->is_top())
3350 continue;
3351 // First, update mergemem by moving memory nodes to corresponding slices
3352 // if their type became more precise since this mergemem was created.
3353 while (mem->is_Mem()) {
3354 const Type *at = igvn->type(mem->in(MemNode::Address));
3355 if (at != Type::TOP) {
3356 assert (at->isa_ptr() != NULL, "pointer type required.");
3357 uint idx = (uint)_compile->get_alias_index(at->is_ptr());
3358 if (idx == i) {
3359 if (cur == NULL)
3360 cur = mem;
3361 } else {
3362 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
3363 nmm->set_memory_at(idx, mem);
3364 }
3365 }
3366 }
3367 mem = mem->in(MemNode::Memory);
3368 }
3369 nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
3370 // Find any instance of the current type if we haven't encountered
3371 // already a memory slice of the instance along the memory chain.
3372 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3373 if((uint)_compile->get_general_index(ni) == i) {
3374 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
3375 if (nmm->is_empty_memory(m)) {
3376 Node* result = find_inst_mem(mem, ni, orig_phis);
3377 if (_compile->failing()) {
3378 return;
3379 }
3380 nmm->set_memory_at(ni, result);
3381 }
3382 }
3383 }
3384 }
3385 // Find the rest of instances values
3386 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3387 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
3388 Node* result = step_through_mergemem(nmm, ni, tinst);
3389 if (result == nmm->base_memory()) {
3390 // Didn't find instance memory, search through general slice recursively.
3391 result = nmm->memory_at(_compile->get_general_index(ni));
3392 result = find_inst_mem(result, ni, orig_phis);
3393 if (_compile->failing()) {
3394 return;
3395 }
3396 nmm->set_memory_at(ni, result);
3397 }
3398 }
3399 igvn->hash_insert(nmm);
3400 record_for_optimizer(nmm);
3401 }
3402
3403 // Phase 4: Update the inputs of non-instance memory Phis and
3404 // the Memory input of memnodes
3405 // First update the inputs of any non-instance Phi's from
3406 // which we split out an instance Phi. Note we don't have
3407 // to recursively process Phi's encountered on the input memory
3408 // chains as is done in split_memory_phi() since they will
3409 // also be processed here.
3410 for (int j = 0; j < orig_phis.length(); j++) {
3411 PhiNode *phi = orig_phis.at(j);
3412 int alias_idx = _compile->get_alias_index(phi->adr_type());
3413 igvn->hash_delete(phi);
3414 for (uint i = 1; i < phi->req(); i++) {
3415 Node *mem = phi->in(i);
3416 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis);
3417 if (_compile->failing()) {
3418 return;
3419 }
3420 if (mem != new_mem) {
3421 phi->set_req(i, new_mem);
3422 }
3423 }
3424 igvn->hash_insert(phi);
3425 record_for_optimizer(phi);
3426 }
3427
3428 // Update the memory inputs of MemNodes with the value we computed
3429 // in Phase 2 and move stores memory users to corresponding memory slices.
3430 // Disable memory split verification code until the fix for 6984348.
3431 // Currently it produces false negative results since it does not cover all cases.
3432 #if 0 // ifdef ASSERT
3433 visited.Reset();
3434 Node_Stack old_mems(arena, _compile->unique() >> 2);
3435 #endif
3436 for (uint i = 0; i < ideal_nodes.size(); i++) {
3437 Node* n = ideal_nodes.at(i);
3438 Node* nmem = get_map(n->_idx);
3439 assert(nmem != NULL, "sanity");
3440 if (n->is_Mem()) {
3441 #if 0 // ifdef ASSERT
3442 Node* old_mem = n->in(MemNode::Memory);
3443 if (!visited.test_set(old_mem->_idx)) {
3444 old_mems.push(old_mem, old_mem->outcnt());
3445 }
3446 #endif
3447 assert(n->in(MemNode::Memory) != nmem, "sanity");
3448 if (!n->is_Load()) {
3449 // Move memory users of a store first.
3450 move_inst_mem(n, orig_phis);
3451 }
3452 // Now update memory input
3453 igvn->hash_delete(n);
3454 n->set_req(MemNode::Memory, nmem);
3455 igvn->hash_insert(n);
3456 record_for_optimizer(n);
3457 } else {
3458 assert(n->is_Allocate() || n->is_CheckCastPP() ||
3459 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()");
3460 }
3461 }
3462 #if 0 // ifdef ASSERT
3463 // Verify that memory was split correctly
3464 while (old_mems.is_nonempty()) {
3465 Node* old_mem = old_mems.node();
3466 uint old_cnt = old_mems.index();
3467 old_mems.pop();
3468 assert(old_cnt == old_mem->outcnt(), "old mem could be lost");
3469 }
3470 #endif
3471 }
3472
3473 #ifndef PRODUCT
3474 static const char *node_type_names[] = {
3475 "UnknownType",
3476 "JavaObject",
3477 "LocalVar",
3478 "Field",
3479 "Arraycopy"
3480 };
3481
3482 static const char *esc_names[] = {
3483 "UnknownEscape",
3484 "NoEscape",
3485 "ArgEscape",
3486 "GlobalEscape"
3487 };
3488
3489 void PointsToNode::dump(bool print_state) const {
3490 NodeType nt = node_type();
3491 tty->print("%s ", node_type_names[(int) nt]);
3492 if (print_state) {
3493 EscapeState es = escape_state();
3494 EscapeState fields_es = fields_escape_state();
3495 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]);
3496 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable())
3497 tty->print("NSR ");
3498 }
3499 if (is_Field()) {
3500 FieldNode* f = (FieldNode*)this;
3501 if (f->is_oop())
3502 tty->print("oop ");
3503 if (f->offset() > 0)
3504 tty->print("+%d ", f->offset());
3505 tty->print("(");
3506 for (BaseIterator i(f); i.has_next(); i.next()) {
3507 PointsToNode* b = i.get();
3508 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : ""));
3509 }
3510 tty->print(" )");
3511 }
3512 tty->print("[");
3513 for (EdgeIterator i(this); i.has_next(); i.next()) {
3514 PointsToNode* e = i.get();
3515 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : "");
3516 }
3517 tty->print(" [");
3518 for (UseIterator i(this); i.has_next(); i.next()) {
3519 PointsToNode* u = i.get();
3520 bool is_base = false;
3521 if (PointsToNode::is_base_use(u)) {
3522 is_base = true;
3523 u = PointsToNode::get_use_node(u)->as_Field();
3524 }
3525 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : "");
3526 }
3527 tty->print(" ]] ");
3528 if (_node == NULL)
3529 tty->print_cr("<null>");
3530 else
3531 _node->dump();
3532 }
3533
3534 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) {
3535 bool first = true;
3536 int ptnodes_length = ptnodes_worklist.length();
3537 for (int i = 0; i < ptnodes_length; i++) {
3538 PointsToNode *ptn = ptnodes_worklist.at(i);
3539 if (ptn == NULL || !ptn->is_JavaObject())
3540 continue;
3541 PointsToNode::EscapeState es = ptn->escape_state();
3542 if ((es != PointsToNode::NoEscape) && !Verbose) {
3543 continue;
3544 }
3545 Node* n = ptn->ideal_node();
3546 if (n->is_Allocate() || (n->is_CallStaticJava() &&
3547 n->as_CallStaticJava()->is_boxing_method())) {
3548 if (first) {
3549 tty->cr();
3550 tty->print("======== Connection graph for ");
3551 _compile->method()->print_short_name();
3552 tty->cr();
3553 first = false;
3554 }
3555 ptn->dump();
3556 // Print all locals and fields which reference this allocation
3557 for (UseIterator j(ptn); j.has_next(); j.next()) {
3558 PointsToNode* use = j.get();
3559 if (use->is_LocalVar()) {
3560 use->dump(Verbose);
3561 } else if (Verbose) {
3562 use->dump();
3563 }
3564 }
3565 tty->cr();
3566 }
3567 }
3568 }
3569 #endif