1 /*
2 * Copyright (c) 2005, 2022, 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 "gc/shared/barrierSet.hpp"
29 #include "gc/shared/c2/barrierSetC2.hpp"
30 #include "libadt/vectset.hpp"
31 #include "memory/allocation.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "opto/c2compiler.hpp"
34 #include "opto/arraycopynode.hpp"
35 #include "opto/callnode.hpp"
36 #include "opto/cfgnode.hpp"
37 #include "opto/compile.hpp"
38 #include "opto/escape.hpp"
39 #include "opto/phaseX.hpp"
40 #include "opto/movenode.hpp"
41 #include "opto/rootnode.hpp"
42 #include "utilities/macros.hpp"
43
44 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn, int invocation) :
45 _nodes(C->comp_arena(), C->unique(), C->unique(), NULL),
46 _in_worklist(C->comp_arena()),
47 _next_pidx(0),
48 _collecting(true),
49 _verify(false),
50 _compile(C),
51 _igvn(igvn),
52 _invocation(invocation),
53 _build_iterations(0),
54 _build_time(0.),
55 _node_map(C->comp_arena()) {
56 // Add unknown java object.
57 add_java_object(C->top(), PointsToNode::GlobalEscape);
58 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject();
59 // Add ConP(#NULL) and ConN(#NULL) nodes.
60 Node* oop_null = igvn->zerocon(T_OBJECT);
61 assert(oop_null->_idx < nodes_size(), "should be created already");
62 add_java_object(oop_null, PointsToNode::NoEscape);
63 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject();
64 if (UseCompressedOops) {
65 Node* noop_null = igvn->zerocon(T_NARROWOOP);
66 assert(noop_null->_idx < nodes_size(), "should be created already");
67 map_ideal_node(noop_null, null_obj);
68 }
69 }
70
71 bool ConnectionGraph::has_candidates(Compile *C) {
72 // EA brings benefits only when the code has allocations and/or locks which
73 // are represented by ideal Macro nodes.
74 int cnt = C->macro_count();
75 for (int i = 0; i < cnt; i++) {
76 Node *n = C->macro_node(i);
77 if (n->is_Allocate()) {
78 return true;
79 }
80 if (n->is_Lock()) {
81 Node* obj = n->as_Lock()->obj_node()->uncast();
82 if (!(obj->is_Parm() || obj->is_Con())) {
83 return true;
84 }
85 }
86 if (n->is_CallStaticJava() &&
87 n->as_CallStaticJava()->is_boxing_method()) {
88 return true;
89 }
90 }
91 return false;
92 }
93
94 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
95 Compile::TracePhase tp("escapeAnalysis", &Phase::timers[Phase::_t_escapeAnalysis]);
96 ResourceMark rm;
97
98 // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction
99 // to create space for them in ConnectionGraph::_nodes[].
100 Node* oop_null = igvn->zerocon(T_OBJECT);
101 Node* noop_null = igvn->zerocon(T_NARROWOOP);
102 int invocation = 0;
103 if (C->congraph() != NULL) {
104 invocation = C->congraph()->_invocation + 1;
105 }
106 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn, invocation);
107 // Perform escape analysis
108 if (congraph->compute_escape()) {
109 // There are non escaping objects.
110 C->set_congraph(congraph);
111 }
112 // Cleanup.
113 if (oop_null->outcnt() == 0) {
114 igvn->hash_delete(oop_null);
115 }
116 if (noop_null->outcnt() == 0) {
117 igvn->hash_delete(noop_null);
118 }
119 }
120
121 bool ConnectionGraph::compute_escape() {
122 Compile* C = _compile;
123 PhaseGVN* igvn = _igvn;
124
125 // Worklists used by EA.
126 Unique_Node_List delayed_worklist;
127 GrowableArray<Node*> alloc_worklist;
128 GrowableArray<Node*> ptr_cmp_worklist;
129 GrowableArray<MemBarStoreStoreNode*> storestore_worklist;
130 GrowableArray<ArrayCopyNode*> arraycopy_worklist;
131 GrowableArray<PointsToNode*> ptnodes_worklist;
132 GrowableArray<JavaObjectNode*> java_objects_worklist;
133 GrowableArray<JavaObjectNode*> non_escaped_allocs_worklist;
134 GrowableArray<FieldNode*> oop_fields_worklist;
135 GrowableArray<SafePointNode*> sfn_worklist;
136 GrowableArray<MergeMemNode*> mergemem_worklist;
137 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; )
138
139 { Compile::TracePhase tp("connectionGraph", &Phase::timers[Phase::_t_connectionGraph]);
140
141 // 1. Populate Connection Graph (CG) with PointsTo nodes.
142 ideal_nodes.map(C->live_nodes(), NULL); // preallocate space
143 // Initialize worklist
144 if (C->root() != NULL) {
145 ideal_nodes.push(C->root());
146 }
147 // Processed ideal nodes are unique on ideal_nodes list
148 // but several ideal nodes are mapped to the phantom_obj.
149 // To avoid duplicated entries on the following worklists
150 // add the phantom_obj only once to them.
151 ptnodes_worklist.append(phantom_obj);
152 java_objects_worklist.append(phantom_obj);
153 for( uint next = 0; next < ideal_nodes.size(); ++next ) {
154 Node* n = ideal_nodes.at(next);
155 // Create PointsTo nodes and add them to Connection Graph. Called
156 // only once per ideal node since ideal_nodes is Unique_Node list.
157 add_node_to_connection_graph(n, &delayed_worklist);
158 PointsToNode* ptn = ptnode_adr(n->_idx);
159 if (ptn != NULL && ptn != phantom_obj) {
160 ptnodes_worklist.append(ptn);
161 if (ptn->is_JavaObject()) {
162 java_objects_worklist.append(ptn->as_JavaObject());
163 if ((n->is_Allocate() || n->is_CallStaticJava()) &&
164 (ptn->escape_state() < PointsToNode::GlobalEscape)) {
165 // Only allocations and java static calls results are interesting.
166 non_escaped_allocs_worklist.append(ptn->as_JavaObject());
167 }
168 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) {
169 oop_fields_worklist.append(ptn->as_Field());
170 }
171 }
172 // Collect some interesting nodes for further use.
173 switch (n->Opcode()) {
174 case Op_MergeMem:
175 // Collect all MergeMem nodes to add memory slices for
176 // scalar replaceable objects in split_unique_types().
177 mergemem_worklist.append(n->as_MergeMem());
178 break;
179 case Op_CmpP:
180 case Op_CmpN:
181 // Collect compare pointers nodes.
182 if (OptimizePtrCompare) {
183 ptr_cmp_worklist.append(n);
184 }
185 break;
186 case Op_MemBarStoreStore:
187 // Collect all MemBarStoreStore nodes so that depending on the
188 // escape status of the associated Allocate node some of them
189 // may be eliminated.
190 storestore_worklist.append(n->as_MemBarStoreStore());
191 break;
192 case Op_MemBarRelease:
193 if (n->req() > MemBarNode::Precedent) {
194 record_for_optimizer(n);
195 }
196 break;
197 #ifdef ASSERT
198 case Op_AddP:
199 // Collect address nodes for graph verification.
200 addp_worklist.append(n);
201 break;
202 #endif
203 case Op_ArrayCopy:
204 // Keep a list of ArrayCopy nodes so if one of its input is non
205 // escaping, we can record a unique type
206 arraycopy_worklist.append(n->as_ArrayCopy());
207 break;
208 default:
209 // not interested now, ignore...
210 break;
211 }
212 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
213 Node* m = n->fast_out(i); // Get user
214 ideal_nodes.push(m);
215 }
216 if (n->is_SafePoint()) {
217 sfn_worklist.append(n->as_SafePoint());
218 }
219 }
220
221 #ifndef PRODUCT
222 if (_compile->directive()->TraceEscapeAnalysisOption) {
223 tty->print("+++++ Initial worklist for ");
224 _compile->method()->print_name();
225 tty->print_cr(" (ea_inv=%d)", _invocation);
226 for (int i = 0; i < ptnodes_worklist.length(); i++) {
227 PointsToNode* ptn = ptnodes_worklist.at(i);
228 ptn->dump();
229 }
230 tty->print_cr("+++++ Calculating escape states and scalar replaceability");
231 }
232 #endif
233
234 if (non_escaped_allocs_worklist.length() == 0) {
235 _collecting = false;
236 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
237 return false; // Nothing to do.
238 }
239 // Add final simple edges to graph.
240 while(delayed_worklist.size() > 0) {
241 Node* n = delayed_worklist.pop();
242 add_final_edges(n);
243 }
244
245 #ifdef ASSERT
246 if (VerifyConnectionGraph) {
247 // Verify that no new simple edges could be created and all
248 // local vars has edges.
249 _verify = true;
250 int ptnodes_length = ptnodes_worklist.length();
251 for (int next = 0; next < ptnodes_length; ++next) {
252 PointsToNode* ptn = ptnodes_worklist.at(next);
253 add_final_edges(ptn->ideal_node());
254 if (ptn->is_LocalVar() && ptn->edge_count() == 0) {
255 ptn->dump();
256 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity");
257 }
258 }
259 _verify = false;
260 }
261 #endif
262 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes
263 // processing, calls to CI to resolve symbols (types, fields, methods)
264 // referenced in bytecode. During symbol resolution VM may throw
265 // an exception which CI cleans and converts to compilation failure.
266 if (C->failing()) {
267 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
268 return false;
269 }
270
271 // 2. Finish Graph construction by propagating references to all
272 // java objects through graph.
273 if (!complete_connection_graph(ptnodes_worklist, non_escaped_allocs_worklist,
274 java_objects_worklist, oop_fields_worklist)) {
275 // All objects escaped or hit time or iterations limits.
276 _collecting = false;
277 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
278 return false;
279 }
280
281 // 3. Adjust scalar_replaceable state of nonescaping objects and push
282 // scalar replaceable allocations on alloc_worklist for processing
283 // in split_unique_types().
284 GrowableArray<JavaObjectNode*> jobj_worklist;
285 int non_escaped_length = non_escaped_allocs_worklist.length();
286 bool found_nsr_alloc = false;
287 for (int next = 0; next < non_escaped_length; next++) {
288 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
289 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape);
290 Node* n = ptn->ideal_node();
291 if (n->is_Allocate()) {
292 n->as_Allocate()->_is_non_escaping = noescape;
293 }
294 if (noescape && ptn->scalar_replaceable()) {
295 adjust_scalar_replaceable_state(ptn);
296 if (ptn->scalar_replaceable()) {
297 jobj_worklist.push(ptn);
298 } else {
299 found_nsr_alloc = true;
300 }
301 }
302 }
303
304 // Propagate NSR (Not Scalar Replaceable) state.
305 if (found_nsr_alloc) {
306 find_scalar_replaceable_allocs(jobj_worklist);
307 }
308
309 for (int next = 0; next < jobj_worklist.length(); ++next) {
310 JavaObjectNode* jobj = jobj_worklist.at(next);
311 if (jobj->scalar_replaceable()) {
312 alloc_worklist.append(jobj->ideal_node());
313 }
314 }
315
316 #ifdef ASSERT
317 if (VerifyConnectionGraph) {
318 // Verify that graph is complete - no new edges could be added or needed.
319 verify_connection_graph(ptnodes_worklist, non_escaped_allocs_worklist,
320 java_objects_worklist, addp_worklist);
321 }
322 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build");
323 assert(null_obj->escape_state() == PointsToNode::NoEscape &&
324 null_obj->edge_count() == 0 &&
325 !null_obj->arraycopy_src() &&
326 !null_obj->arraycopy_dst(), "sanity");
327 #endif
328
329 _collecting = false;
330
331 } // TracePhase t3("connectionGraph")
332
333 // 4. Optimize ideal graph based on EA information.
334 bool has_non_escaping_obj = (non_escaped_allocs_worklist.length() > 0);
335 if (has_non_escaping_obj) {
336 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist);
337 }
338
339 #ifndef PRODUCT
340 if (PrintEscapeAnalysis) {
341 dump(ptnodes_worklist); // Dump ConnectionGraph
342 }
343 #endif
344
345 #ifdef ASSERT
346 if (VerifyConnectionGraph) {
347 int alloc_length = alloc_worklist.length();
348 for (int next = 0; next < alloc_length; ++next) {
349 Node* n = alloc_worklist.at(next);
350 PointsToNode* ptn = ptnode_adr(n->_idx);
351 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity");
352 }
353 }
354 #endif
355
356 // 5. Separate memory graph for scalar replaceable allcations.
357 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0);
358 if (has_scalar_replaceable_candidates && EliminateAllocations) {
359 assert(C->do_aliasing(), "Aliasing should be enabled");
360 // Now use the escape information to create unique types for
361 // scalar replaceable objects.
362 split_unique_types(alloc_worklist, arraycopy_worklist, mergemem_worklist);
363 if (C->failing()) {
364 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
365 return false;
366 }
367 C->print_method(PHASE_AFTER_EA, 2);
368
369 #ifdef ASSERT
370 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
371 tty->print("=== No allocations eliminated for ");
372 C->method()->print_short_name();
373 if (!EliminateAllocations) {
374 tty->print(" since EliminateAllocations is off ===");
375 } else if(!has_scalar_replaceable_candidates) {
376 tty->print(" since there are no scalar replaceable candidates ===");
377 }
378 tty->cr();
379 #endif
380 }
381
382 // Annotate at safepoints if they have <= ArgEscape objects in their scope and at
383 // java calls if they pass ArgEscape objects as parameters.
384 if (has_non_escaping_obj &&
385 (C->env()->should_retain_local_variables() ||
386 C->env()->jvmti_can_get_owned_monitor_info() ||
387 C->env()->jvmti_can_walk_any_space() ||
388 DeoptimizeObjectsALot)) {
389 int sfn_length = sfn_worklist.length();
390 for (int next = 0; next < sfn_length; next++) {
391 SafePointNode* sfn = sfn_worklist.at(next);
392 sfn->set_has_ea_local_in_scope(has_ea_local_in_scope(sfn));
393 if (sfn->is_CallJava()) {
394 CallJavaNode* call = sfn->as_CallJava();
395 call->set_arg_escape(has_arg_escape(call));
396 }
397 }
398 }
399
400 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
401 return has_non_escaping_obj;
402 }
403
404 // Returns true if there is an object in the scope of sfn that does not escape globally.
405 bool ConnectionGraph::has_ea_local_in_scope(SafePointNode* sfn) {
406 Compile* C = _compile;
407 for (JVMState* jvms = sfn->jvms(); jvms != NULL; jvms = jvms->caller()) {
408 if (C->env()->should_retain_local_variables() || C->env()->jvmti_can_walk_any_space() ||
409 DeoptimizeObjectsALot) {
410 // Jvmti agents can access locals. Must provide info about local objects at runtime.
411 int num_locs = jvms->loc_size();
412 for (int idx = 0; idx < num_locs; idx++) {
413 Node* l = sfn->local(jvms, idx);
414 if (not_global_escape(l)) {
415 return true;
416 }
417 }
418 }
419 if (C->env()->jvmti_can_get_owned_monitor_info() ||
420 C->env()->jvmti_can_walk_any_space() || DeoptimizeObjectsALot) {
421 // Jvmti agents can read monitors. Must provide info about locked objects at runtime.
422 int num_mon = jvms->nof_monitors();
423 for (int idx = 0; idx < num_mon; idx++) {
424 Node* m = sfn->monitor_obj(jvms, idx);
425 if (m != NULL && not_global_escape(m)) {
426 return true;
427 }
428 }
429 }
430 }
431 return false;
432 }
433
434 // Returns true if at least one of the arguments to the call is an object
435 // that does not escape globally.
436 bool ConnectionGraph::has_arg_escape(CallJavaNode* call) {
437 if (call->method() != NULL) {
438 uint max_idx = TypeFunc::Parms + call->method()->arg_size();
439 for (uint idx = TypeFunc::Parms; idx < max_idx; idx++) {
440 Node* p = call->in(idx);
441 if (not_global_escape(p)) {
442 return true;
443 }
444 }
445 } else {
446 const char* name = call->as_CallStaticJava()->_name;
447 assert(name != NULL, "no name");
448 // no arg escapes through uncommon traps
449 if (strcmp(name, "uncommon_trap") != 0) {
450 // process_call_arguments() assumes that all arguments escape globally
451 const TypeTuple* d = call->tf()->domain();
452 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
453 const Type* at = d->field_at(i);
454 if (at->isa_oopptr() != NULL) {
455 return true;
456 }
457 }
458 }
459 }
460 return false;
461 }
462
463
464
465 // Utility function for nodes that load an object
466 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
467 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
468 // ThreadLocal has RawPtr type.
469 const Type* t = _igvn->type(n);
470 if (t->make_ptr() != NULL) {
471 Node* adr = n->in(MemNode::Address);
472 #ifdef ASSERT
473 if (!adr->is_AddP()) {
474 assert(_igvn->type(adr)->isa_rawptr(), "sanity");
475 } else {
476 assert((ptnode_adr(adr->_idx) == NULL ||
477 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity");
478 }
479 #endif
480 add_local_var_and_edge(n, PointsToNode::NoEscape,
481 adr, delayed_worklist);
482 }
483 }
484
485 // Populate Connection Graph with PointsTo nodes and create simple
486 // connection graph edges.
487 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
488 assert(!_verify, "this method should not be called for verification");
489 PhaseGVN* igvn = _igvn;
490 uint n_idx = n->_idx;
491 PointsToNode* n_ptn = ptnode_adr(n_idx);
492 if (n_ptn != NULL) {
493 return; // No need to redefine PointsTo node during first iteration.
494 }
495 int opcode = n->Opcode();
496 bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_to_con_graph(this, igvn, delayed_worklist, n, opcode);
497 if (gc_handled) {
498 return; // Ignore node if already handled by GC.
499 }
500
501 if (n->is_Call()) {
502 // Arguments to allocation and locking don't escape.
503 if (n->is_AbstractLock()) {
504 // Put Lock and Unlock nodes on IGVN worklist to process them during
505 // first IGVN optimization when escape information is still available.
506 record_for_optimizer(n);
507 } else if (n->is_Allocate()) {
508 add_call_node(n->as_Call());
509 record_for_optimizer(n);
510 } else {
511 if (n->is_CallStaticJava()) {
512 const char* name = n->as_CallStaticJava()->_name;
513 if (name != NULL && strcmp(name, "uncommon_trap") == 0) {
514 return; // Skip uncommon traps
515 }
516 }
517 // Don't mark as processed since call's arguments have to be processed.
518 delayed_worklist->push(n);
519 // Check if a call returns an object.
520 if ((n->as_Call()->returns_pointer() &&
521 n->as_Call()->proj_out_or_null(TypeFunc::Parms) != NULL) ||
522 (n->is_CallStaticJava() &&
523 n->as_CallStaticJava()->is_boxing_method())) {
524 add_call_node(n->as_Call());
525 }
526 }
527 return;
528 }
529 // Put this check here to process call arguments since some call nodes
530 // point to phantom_obj.
531 if (n_ptn == phantom_obj || n_ptn == null_obj) {
532 return; // Skip predefined nodes.
533 }
534 switch (opcode) {
535 case Op_AddP: {
536 Node* base = get_addp_base(n);
537 PointsToNode* ptn_base = ptnode_adr(base->_idx);
538 // Field nodes are created for all field types. They are used in
539 // adjust_scalar_replaceable_state() and split_unique_types().
540 // Note, non-oop fields will have only base edges in Connection
541 // Graph because such fields are not used for oop loads and stores.
542 int offset = address_offset(n, igvn);
543 add_field(n, PointsToNode::NoEscape, offset);
544 if (ptn_base == NULL) {
545 delayed_worklist->push(n); // Process it later.
546 } else {
547 n_ptn = ptnode_adr(n_idx);
548 add_base(n_ptn->as_Field(), ptn_base);
549 }
550 break;
551 }
552 case Op_CastX2P: {
553 map_ideal_node(n, phantom_obj);
554 break;
555 }
556 case Op_CastPP:
557 case Op_CheckCastPP:
558 case Op_EncodeP:
559 case Op_DecodeN:
560 case Op_EncodePKlass:
561 case Op_DecodeNKlass: {
562 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), delayed_worklist);
563 break;
564 }
565 case Op_CMoveP: {
566 add_local_var(n, PointsToNode::NoEscape);
567 // Do not add edges during first iteration because some could be
568 // not defined yet.
569 delayed_worklist->push(n);
570 break;
571 }
572 case Op_ConP:
573 case Op_ConN:
574 case Op_ConNKlass: {
575 // assume all oop constants globally escape except for null
576 PointsToNode::EscapeState es;
577 const Type* t = igvn->type(n);
578 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) {
579 es = PointsToNode::NoEscape;
580 } else {
581 es = PointsToNode::GlobalEscape;
582 }
583 add_java_object(n, es);
584 break;
585 }
586 case Op_CreateEx: {
587 // assume that all exception objects globally escape
588 map_ideal_node(n, phantom_obj);
589 break;
590 }
591 case Op_LoadKlass:
592 case Op_LoadNKlass: {
593 // Unknown class is loaded
594 map_ideal_node(n, phantom_obj);
595 break;
596 }
597 case Op_LoadP:
598 case Op_LoadN: {
599 add_objload_to_connection_graph(n, delayed_worklist);
600 break;
601 }
602 case Op_Parm: {
603 map_ideal_node(n, phantom_obj);
604 break;
605 }
606 case Op_PartialSubtypeCheck: {
607 // Produces Null or notNull and is used in only in CmpP so
608 // phantom_obj could be used.
609 map_ideal_node(n, phantom_obj); // Result is unknown
610 break;
611 }
612 case Op_Phi: {
613 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
614 // ThreadLocal has RawPtr type.
615 const Type* t = n->as_Phi()->type();
616 if (t->make_ptr() != NULL) {
617 add_local_var(n, PointsToNode::NoEscape);
618 // Do not add edges during first iteration because some could be
619 // not defined yet.
620 delayed_worklist->push(n);
621 }
622 break;
623 }
624 case Op_Proj: {
625 // we are only interested in the oop result projection from a call
626 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
627 n->in(0)->as_Call()->returns_pointer()) {
628 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), delayed_worklist);
629 }
630 break;
631 }
632 case Op_Rethrow: // Exception object escapes
633 case Op_Return: {
634 if (n->req() > TypeFunc::Parms &&
635 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
636 // Treat Return value as LocalVar with GlobalEscape escape state.
637 add_local_var_and_edge(n, PointsToNode::GlobalEscape, n->in(TypeFunc::Parms), delayed_worklist);
638 }
639 break;
640 }
641 case Op_CompareAndExchangeP:
642 case Op_CompareAndExchangeN:
643 case Op_GetAndSetP:
644 case Op_GetAndSetN: {
645 add_objload_to_connection_graph(n, delayed_worklist);
646 // fall-through
647 }
648 case Op_StoreP:
649 case Op_StoreN:
650 case Op_StoreNKlass:
651 case Op_WeakCompareAndSwapP:
652 case Op_WeakCompareAndSwapN:
653 case Op_CompareAndSwapP:
654 case Op_CompareAndSwapN: {
655 add_to_congraph_unsafe_access(n, opcode, delayed_worklist);
656 break;
657 }
658 case Op_AryEq:
659 case Op_CountPositives:
660 case Op_StrComp:
661 case Op_StrEquals:
662 case Op_StrIndexOf:
663 case Op_StrIndexOfChar:
664 case Op_StrInflatedCopy:
665 case Op_StrCompressedCopy:
666 case Op_EncodeISOArray: {
667 add_local_var(n, PointsToNode::ArgEscape);
668 delayed_worklist->push(n); // Process it later.
669 break;
670 }
671 case Op_ThreadLocal: {
672 add_java_object(n, PointsToNode::ArgEscape);
673 break;
674 }
675 case Op_Blackhole: {
676 // All blackhole pointer arguments are globally escaping.
677 // Only do this if there is at least one pointer argument.
678 // Do not add edges during first iteration because some could be
679 // not defined yet, defer to final step.
680 for (uint i = 0; i < n->req(); i++) {
681 Node* in = n->in(i);
682 if (in != nullptr) {
683 const Type* at = _igvn->type(in);
684 if (!at->isa_ptr()) continue;
685
686 add_local_var(n, PointsToNode::GlobalEscape);
687 delayed_worklist->push(n);
688 break;
689 }
690 }
691 break;
692 }
693 default:
694 ; // Do nothing for nodes not related to EA.
695 }
696 return;
697 }
698
699 // Add final simple edges to graph.
700 void ConnectionGraph::add_final_edges(Node *n) {
701 PointsToNode* n_ptn = ptnode_adr(n->_idx);
702 #ifdef ASSERT
703 if (_verify && n_ptn->is_JavaObject())
704 return; // This method does not change graph for JavaObject.
705 #endif
706
707 if (n->is_Call()) {
708 process_call_arguments(n->as_Call());
709 return;
710 }
711 assert(n->is_Store() || n->is_LoadStore() ||
712 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL),
713 "node should be registered already");
714 int opcode = n->Opcode();
715 bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_final_edges(this, _igvn, n, opcode);
716 if (gc_handled) {
717 return; // Ignore node if already handled by GC.
718 }
719 switch (opcode) {
720 case Op_AddP: {
721 Node* base = get_addp_base(n);
722 PointsToNode* ptn_base = ptnode_adr(base->_idx);
723 assert(ptn_base != NULL, "field's base should be registered");
724 add_base(n_ptn->as_Field(), ptn_base);
725 break;
726 }
727 case Op_CastPP:
728 case Op_CheckCastPP:
729 case Op_EncodeP:
730 case Op_DecodeN:
731 case Op_EncodePKlass:
732 case Op_DecodeNKlass: {
733 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), NULL);
734 break;
735 }
736 case Op_CMoveP: {
737 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) {
738 Node* in = n->in(i);
739 if (in == NULL) {
740 continue; // ignore NULL
741 }
742 Node* uncast_in = in->uncast();
743 if (uncast_in->is_top() || uncast_in == n) {
744 continue; // ignore top or inputs which go back this node
745 }
746 PointsToNode* ptn = ptnode_adr(in->_idx);
747 assert(ptn != NULL, "node should be registered");
748 add_edge(n_ptn, ptn);
749 }
750 break;
751 }
752 case Op_LoadP:
753 case Op_LoadN: {
754 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
755 // ThreadLocal has RawPtr type.
756 assert(_igvn->type(n)->make_ptr() != NULL, "Unexpected node type");
757 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(MemNode::Address), NULL);
758 break;
759 }
760 case Op_Phi: {
761 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
762 // ThreadLocal has RawPtr type.
763 assert(n->as_Phi()->type()->make_ptr() != NULL, "Unexpected node type");
764 for (uint i = 1; i < n->req(); i++) {
765 Node* in = n->in(i);
766 if (in == NULL) {
767 continue; // ignore NULL
768 }
769 Node* uncast_in = in->uncast();
770 if (uncast_in->is_top() || uncast_in == n) {
771 continue; // ignore top or inputs which go back this node
772 }
773 PointsToNode* ptn = ptnode_adr(in->_idx);
774 assert(ptn != NULL, "node should be registered");
775 add_edge(n_ptn, ptn);
776 }
777 break;
778 }
779 case Op_Proj: {
780 // we are only interested in the oop result projection from a call
781 assert(n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
782 n->in(0)->as_Call()->returns_pointer(), "Unexpected node type");
783 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL);
784 break;
785 }
786 case Op_Rethrow: // Exception object escapes
787 case Op_Return: {
788 assert(n->req() > TypeFunc::Parms && _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr(),
789 "Unexpected node type");
790 // Treat Return value as LocalVar with GlobalEscape escape state.
791 add_local_var_and_edge(n, PointsToNode::GlobalEscape, n->in(TypeFunc::Parms), NULL);
792 break;
793 }
794 case Op_CompareAndExchangeP:
795 case Op_CompareAndExchangeN:
796 case Op_GetAndSetP:
797 case Op_GetAndSetN:{
798 assert(_igvn->type(n)->make_ptr() != NULL, "Unexpected node type");
799 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(MemNode::Address), NULL);
800 // fall-through
801 }
802 case Op_CompareAndSwapP:
803 case Op_CompareAndSwapN:
804 case Op_WeakCompareAndSwapP:
805 case Op_WeakCompareAndSwapN:
806 case Op_StoreP:
807 case Op_StoreN:
808 case Op_StoreNKlass:{
809 add_final_edges_unsafe_access(n, opcode);
810 break;
811 }
812 case Op_AryEq:
813 case Op_CountPositives:
814 case Op_StrComp:
815 case Op_StrEquals:
816 case Op_StrIndexOf:
817 case Op_StrIndexOfChar:
818 case Op_StrInflatedCopy:
819 case Op_StrCompressedCopy:
820 case Op_EncodeISOArray: {
821 // char[]/byte[] arrays passed to string intrinsic do not escape but
822 // they are not scalar replaceable. Adjust escape state for them.
823 // Start from in(2) edge since in(1) is memory edge.
824 for (uint i = 2; i < n->req(); i++) {
825 Node* adr = n->in(i);
826 const Type* at = _igvn->type(adr);
827 if (!adr->is_top() && at->isa_ptr()) {
828 assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
829 at->isa_ptr() != NULL, "expecting a pointer");
830 if (adr->is_AddP()) {
831 adr = get_addp_base(adr);
832 }
833 PointsToNode* ptn = ptnode_adr(adr->_idx);
834 assert(ptn != NULL, "node should be registered");
835 add_edge(n_ptn, ptn);
836 }
837 }
838 break;
839 }
840 case Op_Blackhole: {
841 // All blackhole pointer arguments are globally escaping.
842 for (uint i = 0; i < n->req(); i++) {
843 Node* in = n->in(i);
844 if (in != nullptr) {
845 const Type* at = _igvn->type(in);
846 if (!at->isa_ptr()) continue;
847
848 if (in->is_AddP()) {
849 in = get_addp_base(in);
850 }
851
852 PointsToNode* ptn = ptnode_adr(in->_idx);
853 assert(ptn != nullptr, "should be defined already");
854 set_escape_state(ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA "blackhole"));
855 add_edge(n_ptn, ptn);
856 }
857 }
858 break;
859 }
860 default: {
861 // This method should be called only for EA specific nodes which may
862 // miss some edges when they were created.
863 #ifdef ASSERT
864 n->dump(1);
865 #endif
866 guarantee(false, "unknown node");
867 }
868 }
869 return;
870 }
871
872 void ConnectionGraph::add_to_congraph_unsafe_access(Node* n, uint opcode, Unique_Node_List* delayed_worklist) {
873 Node* adr = n->in(MemNode::Address);
874 const Type* adr_type = _igvn->type(adr);
875 adr_type = adr_type->make_ptr();
876 if (adr_type == NULL) {
877 return; // skip dead nodes
878 }
879 if (adr_type->isa_oopptr()
880 || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
881 && adr_type == TypeRawPtr::NOTNULL
882 && is_captured_store_address(adr))) {
883 delayed_worklist->push(n); // Process it later.
884 #ifdef ASSERT
885 assert (adr->is_AddP(), "expecting an AddP");
886 if (adr_type == TypeRawPtr::NOTNULL) {
887 // Verify a raw address for a store captured by Initialize node.
888 int offs = (int) _igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
889 assert(offs != Type::OffsetBot, "offset must be a constant");
890 }
891 #endif
892 } else {
893 // Ignore copy the displaced header to the BoxNode (OSR compilation).
894 if (adr->is_BoxLock()) {
895 return;
896 }
897 // Stored value escapes in unsafe access.
898 if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
899 delayed_worklist->push(n); // Process unsafe access later.
900 return;
901 }
902 #ifdef ASSERT
903 n->dump(1);
904 assert(false, "not unsafe");
905 #endif
906 }
907 }
908
909 bool ConnectionGraph::add_final_edges_unsafe_access(Node* n, uint opcode) {
910 Node* adr = n->in(MemNode::Address);
911 const Type *adr_type = _igvn->type(adr);
912 adr_type = adr_type->make_ptr();
913 #ifdef ASSERT
914 if (adr_type == NULL) {
915 n->dump(1);
916 assert(adr_type != NULL, "dead node should not be on list");
917 return true;
918 }
919 #endif
920
921 if (adr_type->isa_oopptr()
922 || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
923 && adr_type == TypeRawPtr::NOTNULL
924 && is_captured_store_address(adr))) {
925 // Point Address to Value
926 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
927 assert(adr_ptn != NULL &&
928 adr_ptn->as_Field()->is_oop(), "node should be registered");
929 Node* val = n->in(MemNode::ValueIn);
930 PointsToNode* ptn = ptnode_adr(val->_idx);
931 assert(ptn != NULL, "node should be registered");
932 add_edge(adr_ptn, ptn);
933 return true;
934 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
935 // Stored value escapes in unsafe access.
936 Node* val = n->in(MemNode::ValueIn);
937 PointsToNode* ptn = ptnode_adr(val->_idx);
938 assert(ptn != NULL, "node should be registered");
939 set_escape_state(ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA "stored at raw address"));
940 // Add edge to object for unsafe access with offset.
941 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
942 assert(adr_ptn != NULL, "node should be registered");
943 if (adr_ptn->is_Field()) {
944 assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
945 add_edge(adr_ptn, ptn);
946 }
947 return true;
948 }
949 #ifdef ASSERT
950 n->dump(1);
951 assert(false, "not unsafe");
952 #endif
953 return false;
954 }
955
956 void ConnectionGraph::add_call_node(CallNode* call) {
957 assert(call->returns_pointer(), "only for call which returns pointer");
958 uint call_idx = call->_idx;
959 if (call->is_Allocate()) {
960 Node* k = call->in(AllocateNode::KlassNode);
961 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr();
962 assert(kt != NULL, "TypeKlassPtr required.");
963 PointsToNode::EscapeState es = PointsToNode::NoEscape;
964 bool scalar_replaceable = true;
965 NOT_PRODUCT(const char* nsr_reason = "");
966 if (call->is_AllocateArray()) {
967 if (!kt->isa_aryklassptr()) { // StressReflectiveCode
968 es = PointsToNode::GlobalEscape;
969 } else {
970 int length = call->in(AllocateNode::ALength)->find_int_con(-1);
971 if (length < 0) {
972 // Not scalar replaceable if the length is not constant.
973 scalar_replaceable = false;
974 NOT_PRODUCT(nsr_reason = "has a non-constant length");
975 } else if (length > EliminateAllocationArraySizeLimit) {
976 // Not scalar replaceable if the length is too big.
977 scalar_replaceable = false;
978 NOT_PRODUCT(nsr_reason = "has a length that is too big");
979 }
980 }
981 } else { // Allocate instance
982 if (!kt->isa_instklassptr()) { // StressReflectiveCode
983 es = PointsToNode::GlobalEscape;
984 } else {
985 const TypeInstKlassPtr* ikt = kt->is_instklassptr();
986 ciInstanceKlass* ik = ikt->klass_is_exact() ? ikt->exact_klass()->as_instance_klass() : ikt->instance_klass();
987 if (ik->is_subclass_of(_compile->env()->Thread_klass()) ||
988 ik->is_subclass_of(_compile->env()->Reference_klass()) ||
989 !ik->can_be_instantiated() ||
990 ik->has_finalizer()) {
991 es = PointsToNode::GlobalEscape;
992 } else {
993 int nfields = ik->as_instance_klass()->nof_nonstatic_fields();
994 if (nfields > EliminateAllocationFieldsLimit) {
995 // Not scalar replaceable if there are too many fields.
996 scalar_replaceable = false;
997 NOT_PRODUCT(nsr_reason = "has too many fields");
998 }
999 }
1000 }
1001 }
1002 add_java_object(call, es);
1003 PointsToNode* ptn = ptnode_adr(call_idx);
1004 if (!scalar_replaceable && ptn->scalar_replaceable()) {
1005 set_not_scalar_replaceable(ptn NOT_PRODUCT(COMMA nsr_reason));
1006 }
1007 } else if (call->is_CallStaticJava()) {
1008 // Call nodes could be different types:
1009 //
1010 // 1. CallDynamicJavaNode (what happened during call is unknown):
1011 //
1012 // - mapped to GlobalEscape JavaObject node if oop is returned;
1013 //
1014 // - all oop arguments are escaping globally;
1015 //
1016 // 2. CallStaticJavaNode (execute bytecode analysis if possible):
1017 //
1018 // - the same as CallDynamicJavaNode if can't do bytecode analysis;
1019 //
1020 // - mapped to GlobalEscape JavaObject node if unknown oop is returned;
1021 // - mapped to NoEscape JavaObject node if non-escaping object allocated
1022 // during call is returned;
1023 // - mapped to ArgEscape LocalVar node pointed to object arguments
1024 // which are returned and does not escape during call;
1025 //
1026 // - oop arguments escaping status is defined by bytecode analysis;
1027 //
1028 // For a static call, we know exactly what method is being called.
1029 // Use bytecode estimator to record whether the call's return value escapes.
1030 ciMethod* meth = call->as_CallJava()->method();
1031 if (meth == NULL) {
1032 const char* name = call->as_CallStaticJava()->_name;
1033 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check");
1034 // Returns a newly allocated non-escaped object.
1035 add_java_object(call, PointsToNode::NoEscape);
1036 set_not_scalar_replaceable(ptnode_adr(call_idx) NOT_PRODUCT(COMMA "is result of multinewarray"));
1037 } else if (meth->is_boxing_method()) {
1038 // Returns boxing object
1039 PointsToNode::EscapeState es;
1040 vmIntrinsics::ID intr = meth->intrinsic_id();
1041 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) {
1042 // It does not escape if object is always allocated.
1043 es = PointsToNode::NoEscape;
1044 } else {
1045 // It escapes globally if object could be loaded from cache.
1046 es = PointsToNode::GlobalEscape;
1047 }
1048 add_java_object(call, es);
1049 } else {
1050 BCEscapeAnalyzer* call_analyzer = meth->get_bcea();
1051 call_analyzer->copy_dependencies(_compile->dependencies());
1052 if (call_analyzer->is_return_allocated()) {
1053 // Returns a newly allocated non-escaped object, simply
1054 // update dependency information.
1055 // Mark it as NoEscape so that objects referenced by
1056 // it's fields will be marked as NoEscape at least.
1057 add_java_object(call, PointsToNode::NoEscape);
1058 set_not_scalar_replaceable(ptnode_adr(call_idx) NOT_PRODUCT(COMMA "is result of call"));
1059 } else {
1060 // Determine whether any arguments are returned.
1061 const TypeTuple* d = call->tf()->domain();
1062 bool ret_arg = false;
1063 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1064 if (d->field_at(i)->isa_ptr() != NULL &&
1065 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
1066 ret_arg = true;
1067 break;
1068 }
1069 }
1070 if (ret_arg) {
1071 add_local_var(call, PointsToNode::ArgEscape);
1072 } else {
1073 // Returns unknown object.
1074 map_ideal_node(call, phantom_obj);
1075 }
1076 }
1077 }
1078 } else {
1079 // An other type of call, assume the worst case:
1080 // returned value is unknown and globally escapes.
1081 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check");
1082 map_ideal_node(call, phantom_obj);
1083 }
1084 }
1085
1086 void ConnectionGraph::process_call_arguments(CallNode *call) {
1087 bool is_arraycopy = false;
1088 switch (call->Opcode()) {
1089 #ifdef ASSERT
1090 case Op_Allocate:
1091 case Op_AllocateArray:
1092 case Op_Lock:
1093 case Op_Unlock:
1094 assert(false, "should be done already");
1095 break;
1096 #endif
1097 case Op_ArrayCopy:
1098 case Op_CallLeafNoFP:
1099 // Most array copies are ArrayCopy nodes at this point but there
1100 // are still a few direct calls to the copy subroutines (See
1101 // PhaseStringOpts::copy_string())
1102 is_arraycopy = (call->Opcode() == Op_ArrayCopy) ||
1103 call->as_CallLeaf()->is_call_to_arraycopystub();
1104 // fall through
1105 case Op_CallLeafVector:
1106 case Op_CallLeaf: {
1107 // Stub calls, objects do not escape but they are not scale replaceable.
1108 // Adjust escape state for outgoing arguments.
1109 const TypeTuple * d = call->tf()->domain();
1110 bool src_has_oops = false;
1111 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1112 const Type* at = d->field_at(i);
1113 Node *arg = call->in(i);
1114 if (arg == NULL) {
1115 continue;
1116 }
1117 const Type *aat = _igvn->type(arg);
1118 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) {
1119 continue;
1120 }
1121 if (arg->is_AddP()) {
1122 //
1123 // The inline_native_clone() case when the arraycopy stub is called
1124 // after the allocation before Initialize and CheckCastPP nodes.
1125 // Or normal arraycopy for object arrays case.
1126 //
1127 // Set AddP's base (Allocate) as not scalar replaceable since
1128 // pointer to the base (with offset) is passed as argument.
1129 //
1130 arg = get_addp_base(arg);
1131 }
1132 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1133 assert(arg_ptn != NULL, "should be registered");
1134 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state();
1135 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) {
1136 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
1137 aat->isa_ptr() != NULL, "expecting an Ptr");
1138 bool arg_has_oops = aat->isa_oopptr() &&
1139 (aat->isa_instptr() ||
1140 (aat->isa_aryptr() && (aat->isa_aryptr()->elem() == Type::BOTTOM || aat->isa_aryptr()->elem()->make_oopptr() != NULL)));
1141 if (i == TypeFunc::Parms) {
1142 src_has_oops = arg_has_oops;
1143 }
1144 //
1145 // src or dst could be j.l.Object when other is basic type array:
1146 //
1147 // arraycopy(char[],0,Object*,0,size);
1148 // arraycopy(Object*,0,char[],0,size);
1149 //
1150 // Don't add edges in such cases.
1151 //
1152 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy &&
1153 arg_has_oops && (i > TypeFunc::Parms);
1154 #ifdef ASSERT
1155 if (!(is_arraycopy ||
1156 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(call) ||
1157 (call->as_CallLeaf()->_name != NULL &&
1158 (strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 ||
1159 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 ||
1160 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 ||
1161 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 ||
1162 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 ||
1163 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 ||
1164 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 ||
1165 strcmp(call->as_CallLeaf()->_name, "electronicCodeBook_encryptAESCrypt") == 0 ||
1166 strcmp(call->as_CallLeaf()->_name, "electronicCodeBook_decryptAESCrypt") == 0 ||
1167 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 ||
1168 strcmp(call->as_CallLeaf()->_name, "galoisCounterMode_AESCrypt") == 0 ||
1169 strcmp(call->as_CallLeaf()->_name, "poly1305_processBlocks") == 0 ||
1170 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 ||
1171 strcmp(call->as_CallLeaf()->_name, "chacha20Block") == 0 ||
1172 strcmp(call->as_CallLeaf()->_name, "encodeBlock") == 0 ||
1173 strcmp(call->as_CallLeaf()->_name, "decodeBlock") == 0 ||
1174 strcmp(call->as_CallLeaf()->_name, "md5_implCompress") == 0 ||
1175 strcmp(call->as_CallLeaf()->_name, "md5_implCompressMB") == 0 ||
1176 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 ||
1177 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 ||
1178 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 ||
1179 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 ||
1180 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 ||
1181 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 ||
1182 strcmp(call->as_CallLeaf()->_name, "sha3_implCompress") == 0 ||
1183 strcmp(call->as_CallLeaf()->_name, "sha3_implCompressMB") == 0 ||
1184 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 ||
1185 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 ||
1186 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 ||
1187 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 ||
1188 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 ||
1189 strcmp(call->as_CallLeaf()->_name, "bigIntegerRightShiftWorker") == 0 ||
1190 strcmp(call->as_CallLeaf()->_name, "bigIntegerLeftShiftWorker") == 0 ||
1191 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0 ||
1192 strcmp(call->as_CallLeaf()->_name, "get_class_id_intrinsic") == 0)
1193 ))) {
1194 call->dump();
1195 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name);
1196 }
1197 #endif
1198 // Always process arraycopy's destination object since
1199 // we need to add all possible edges to references in
1200 // source object.
1201 if (arg_esc >= PointsToNode::ArgEscape &&
1202 !arg_is_arraycopy_dest) {
1203 continue;
1204 }
1205 PointsToNode::EscapeState es = PointsToNode::ArgEscape;
1206 if (call->is_ArrayCopy()) {
1207 ArrayCopyNode* ac = call->as_ArrayCopy();
1208 if (ac->is_clonebasic() ||
1209 ac->is_arraycopy_validated() ||
1210 ac->is_copyof_validated() ||
1211 ac->is_copyofrange_validated()) {
1212 es = PointsToNode::NoEscape;
1213 }
1214 }
1215 set_escape_state(arg_ptn, es NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1216 if (arg_is_arraycopy_dest) {
1217 Node* src = call->in(TypeFunc::Parms);
1218 if (src->is_AddP()) {
1219 src = get_addp_base(src);
1220 }
1221 PointsToNode* src_ptn = ptnode_adr(src->_idx);
1222 assert(src_ptn != NULL, "should be registered");
1223 if (arg_ptn != src_ptn) {
1224 // Special arraycopy edge:
1225 // A destination object's field can't have the source object
1226 // as base since objects escape states are not related.
1227 // Only escape state of destination object's fields affects
1228 // escape state of fields in source object.
1229 add_arraycopy(call, es, src_ptn, arg_ptn);
1230 }
1231 }
1232 }
1233 }
1234 break;
1235 }
1236 case Op_CallStaticJava: {
1237 // For a static call, we know exactly what method is being called.
1238 // Use bytecode estimator to record the call's escape affects
1239 #ifdef ASSERT
1240 const char* name = call->as_CallStaticJava()->_name;
1241 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only");
1242 #endif
1243 ciMethod* meth = call->as_CallJava()->method();
1244 if ((meth != NULL) && meth->is_boxing_method()) {
1245 break; // Boxing methods do not modify any oops.
1246 }
1247 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
1248 // fall-through if not a Java method or no analyzer information
1249 if (call_analyzer != NULL) {
1250 PointsToNode* call_ptn = ptnode_adr(call->_idx);
1251 const TypeTuple* d = call->tf()->domain();
1252 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1253 const Type* at = d->field_at(i);
1254 int k = i - TypeFunc::Parms;
1255 Node* arg = call->in(i);
1256 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1257 if (at->isa_ptr() != NULL &&
1258 call_analyzer->is_arg_returned(k)) {
1259 // The call returns arguments.
1260 if (call_ptn != NULL) { // Is call's result used?
1261 assert(call_ptn->is_LocalVar(), "node should be registered");
1262 assert(arg_ptn != NULL, "node should be registered");
1263 add_edge(call_ptn, arg_ptn);
1264 }
1265 }
1266 if (at->isa_oopptr() != NULL &&
1267 arg_ptn->escape_state() < PointsToNode::GlobalEscape) {
1268 if (!call_analyzer->is_arg_stack(k)) {
1269 // The argument global escapes
1270 set_escape_state(arg_ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1271 } else {
1272 set_escape_state(arg_ptn, PointsToNode::ArgEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1273 if (!call_analyzer->is_arg_local(k)) {
1274 // The argument itself doesn't escape, but any fields might
1275 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1276 }
1277 }
1278 }
1279 }
1280 if (call_ptn != NULL && call_ptn->is_LocalVar()) {
1281 // The call returns arguments.
1282 assert(call_ptn->edge_count() > 0, "sanity");
1283 if (!call_analyzer->is_return_local()) {
1284 // Returns also unknown object.
1285 add_edge(call_ptn, phantom_obj);
1286 }
1287 }
1288 break;
1289 }
1290 }
1291 default: {
1292 // Fall-through here if not a Java method or no analyzer information
1293 // or some other type of call, assume the worst case: all arguments
1294 // globally escape.
1295 const TypeTuple* d = call->tf()->domain();
1296 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1297 const Type* at = d->field_at(i);
1298 if (at->isa_oopptr() != NULL) {
1299 Node* arg = call->in(i);
1300 if (arg->is_AddP()) {
1301 arg = get_addp_base(arg);
1302 }
1303 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already");
1304 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1305 }
1306 }
1307 }
1308 }
1309 }
1310
1311
1312 // Finish Graph construction.
1313 bool ConnectionGraph::complete_connection_graph(
1314 GrowableArray<PointsToNode*>& ptnodes_worklist,
1315 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist,
1316 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1317 GrowableArray<FieldNode*>& oop_fields_worklist) {
1318 // Normally only 1-3 passes needed to build Connection Graph depending
1319 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler.
1320 // Set limit to 20 to catch situation when something did go wrong and
1321 // bailout Escape Analysis.
1322 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag.
1323 #define GRAPH_BUILD_ITER_LIMIT 20
1324
1325 // Propagate GlobalEscape and ArgEscape escape states and check that
1326 // we still have non-escaping objects. The method pushs on _worklist
1327 // Field nodes which reference phantom_object.
1328 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist)) {
1329 return false; // Nothing to do.
1330 }
1331 // Now propagate references to all JavaObject nodes.
1332 int java_objects_length = java_objects_worklist.length();
1333 elapsedTimer build_time;
1334 build_time.start();
1335 elapsedTimer time;
1336 bool timeout = false;
1337 int new_edges = 1;
1338 int iterations = 0;
1339 do {
1340 while ((new_edges > 0) &&
1341 (iterations++ < GRAPH_BUILD_ITER_LIMIT)) {
1342 double start_time = time.seconds();
1343 time.start();
1344 new_edges = 0;
1345 // Propagate references to phantom_object for nodes pushed on _worklist
1346 // by find_non_escaped_objects() and find_field_value().
1347 new_edges += add_java_object_edges(phantom_obj, false);
1348 for (int next = 0; next < java_objects_length; ++next) {
1349 JavaObjectNode* ptn = java_objects_worklist.at(next);
1350 new_edges += add_java_object_edges(ptn, true);
1351
1352 #define SAMPLE_SIZE 4
1353 if ((next % SAMPLE_SIZE) == 0) {
1354 // Each 4 iterations calculate how much time it will take
1355 // to complete graph construction.
1356 time.stop();
1357 // Poll for requests from shutdown mechanism to quiesce compiler
1358 // because Connection graph construction may take long time.
1359 CompileBroker::maybe_block();
1360 double stop_time = time.seconds();
1361 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE;
1362 double time_until_end = time_per_iter * (double)(java_objects_length - next);
1363 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) {
1364 timeout = true;
1365 break; // Timeout
1366 }
1367 start_time = stop_time;
1368 time.start();
1369 }
1370 #undef SAMPLE_SIZE
1371
1372 }
1373 if (timeout) break;
1374 if (new_edges > 0) {
1375 // Update escape states on each iteration if graph was updated.
1376 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist)) {
1377 return false; // Nothing to do.
1378 }
1379 }
1380 time.stop();
1381 if (time.seconds() >= EscapeAnalysisTimeout) {
1382 timeout = true;
1383 break;
1384 }
1385 }
1386 if ((iterations < GRAPH_BUILD_ITER_LIMIT) && !timeout) {
1387 time.start();
1388 // Find fields which have unknown value.
1389 int fields_length = oop_fields_worklist.length();
1390 for (int next = 0; next < fields_length; next++) {
1391 FieldNode* field = oop_fields_worklist.at(next);
1392 if (field->edge_count() == 0) {
1393 new_edges += find_field_value(field);
1394 // This code may added new edges to phantom_object.
1395 // Need an other cycle to propagate references to phantom_object.
1396 }
1397 }
1398 time.stop();
1399 if (time.seconds() >= EscapeAnalysisTimeout) {
1400 timeout = true;
1401 break;
1402 }
1403 } else {
1404 new_edges = 0; // Bailout
1405 }
1406 } while (new_edges > 0);
1407
1408 build_time.stop();
1409 _build_time = build_time.seconds();
1410 _build_iterations = iterations;
1411
1412 // Bailout if passed limits.
1413 if ((iterations >= GRAPH_BUILD_ITER_LIMIT) || timeout) {
1414 Compile* C = _compile;
1415 if (C->log() != NULL) {
1416 C->log()->begin_elem("connectionGraph_bailout reason='reached ");
1417 C->log()->text("%s", timeout ? "time" : "iterations");
1418 C->log()->end_elem(" limit'");
1419 }
1420 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build during invocation %d (%f sec, %d iterations) with %d nodes and worklist size %d",
1421 _invocation, _build_time, _build_iterations, nodes_size(), ptnodes_worklist.length());
1422 // Possible infinite build_connection_graph loop,
1423 // bailout (no changes to ideal graph were made).
1424 return false;
1425 }
1426
1427 #undef GRAPH_BUILD_ITER_LIMIT
1428
1429 // Find fields initialized by NULL for non-escaping Allocations.
1430 int non_escaped_length = non_escaped_allocs_worklist.length();
1431 for (int next = 0; next < non_escaped_length; next++) {
1432 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
1433 PointsToNode::EscapeState es = ptn->escape_state();
1434 assert(es <= PointsToNode::ArgEscape, "sanity");
1435 if (es == PointsToNode::NoEscape) {
1436 if (find_init_values_null(ptn, _igvn) > 0) {
1437 // Adding references to NULL object does not change escape states
1438 // since it does not escape. Also no fields are added to NULL object.
1439 add_java_object_edges(null_obj, false);
1440 }
1441 }
1442 Node* n = ptn->ideal_node();
1443 if (n->is_Allocate()) {
1444 // The object allocated by this Allocate node will never be
1445 // seen by an other thread. Mark it so that when it is
1446 // expanded no MemBarStoreStore is added.
1447 InitializeNode* ini = n->as_Allocate()->initialization();
1448 if (ini != NULL)
1449 ini->set_does_not_escape();
1450 }
1451 }
1452 return true; // Finished graph construction.
1453 }
1454
1455 // Propagate GlobalEscape and ArgEscape escape states to all nodes
1456 // and check that we still have non-escaping java objects.
1457 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist,
1458 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist) {
1459 GrowableArray<PointsToNode*> escape_worklist;
1460 // First, put all nodes with GlobalEscape and ArgEscape states on worklist.
1461 int ptnodes_length = ptnodes_worklist.length();
1462 for (int next = 0; next < ptnodes_length; ++next) {
1463 PointsToNode* ptn = ptnodes_worklist.at(next);
1464 if (ptn->escape_state() >= PointsToNode::ArgEscape ||
1465 ptn->fields_escape_state() >= PointsToNode::ArgEscape) {
1466 escape_worklist.push(ptn);
1467 }
1468 }
1469 // Set escape states to referenced nodes (edges list).
1470 while (escape_worklist.length() > 0) {
1471 PointsToNode* ptn = escape_worklist.pop();
1472 PointsToNode::EscapeState es = ptn->escape_state();
1473 PointsToNode::EscapeState field_es = ptn->fields_escape_state();
1474 if (ptn->is_Field() && ptn->as_Field()->is_oop() &&
1475 es >= PointsToNode::ArgEscape) {
1476 // GlobalEscape or ArgEscape state of field means it has unknown value.
1477 if (add_edge(ptn, phantom_obj)) {
1478 // New edge was added
1479 add_field_uses_to_worklist(ptn->as_Field());
1480 }
1481 }
1482 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1483 PointsToNode* e = i.get();
1484 if (e->is_Arraycopy()) {
1485 assert(ptn->arraycopy_dst(), "sanity");
1486 // Propagate only fields escape state through arraycopy edge.
1487 if (e->fields_escape_state() < field_es) {
1488 set_fields_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1489 escape_worklist.push(e);
1490 }
1491 } else if (es >= field_es) {
1492 // fields_escape_state is also set to 'es' if it is less than 'es'.
1493 if (e->escape_state() < es) {
1494 set_escape_state(e, es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1495 escape_worklist.push(e);
1496 }
1497 } else {
1498 // Propagate field escape state.
1499 bool es_changed = false;
1500 if (e->fields_escape_state() < field_es) {
1501 set_fields_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1502 es_changed = true;
1503 }
1504 if ((e->escape_state() < field_es) &&
1505 e->is_Field() && ptn->is_JavaObject() &&
1506 e->as_Field()->is_oop()) {
1507 // Change escape state of referenced fields.
1508 set_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1509 es_changed = true;
1510 } else if (e->escape_state() < es) {
1511 set_escape_state(e, es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1512 es_changed = true;
1513 }
1514 if (es_changed) {
1515 escape_worklist.push(e);
1516 }
1517 }
1518 }
1519 }
1520 // Remove escaped objects from non_escaped list.
1521 for (int next = non_escaped_allocs_worklist.length()-1; next >= 0 ; --next) {
1522 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
1523 if (ptn->escape_state() >= PointsToNode::GlobalEscape) {
1524 non_escaped_allocs_worklist.delete_at(next);
1525 }
1526 if (ptn->escape_state() == PointsToNode::NoEscape) {
1527 // Find fields in non-escaped allocations which have unknown value.
1528 find_init_values_phantom(ptn);
1529 }
1530 }
1531 return (non_escaped_allocs_worklist.length() > 0);
1532 }
1533
1534 // Add all references to JavaObject node by walking over all uses.
1535 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) {
1536 int new_edges = 0;
1537 if (populate_worklist) {
1538 // Populate _worklist by uses of jobj's uses.
1539 for (UseIterator i(jobj); i.has_next(); i.next()) {
1540 PointsToNode* use = i.get();
1541 if (use->is_Arraycopy()) {
1542 continue;
1543 }
1544 add_uses_to_worklist(use);
1545 if (use->is_Field() && use->as_Field()->is_oop()) {
1546 // Put on worklist all field's uses (loads) and
1547 // related field nodes (same base and offset).
1548 add_field_uses_to_worklist(use->as_Field());
1549 }
1550 }
1551 }
1552 for (int l = 0; l < _worklist.length(); l++) {
1553 PointsToNode* use = _worklist.at(l);
1554 if (PointsToNode::is_base_use(use)) {
1555 // Add reference from jobj to field and from field to jobj (field's base).
1556 use = PointsToNode::get_use_node(use)->as_Field();
1557 if (add_base(use->as_Field(), jobj)) {
1558 new_edges++;
1559 }
1560 continue;
1561 }
1562 assert(!use->is_JavaObject(), "sanity");
1563 if (use->is_Arraycopy()) {
1564 if (jobj == null_obj) { // NULL object does not have field edges
1565 continue;
1566 }
1567 // Added edge from Arraycopy node to arraycopy's source java object
1568 if (add_edge(use, jobj)) {
1569 jobj->set_arraycopy_src();
1570 new_edges++;
1571 }
1572 // and stop here.
1573 continue;
1574 }
1575 if (!add_edge(use, jobj)) {
1576 continue; // No new edge added, there was such edge already.
1577 }
1578 new_edges++;
1579 if (use->is_LocalVar()) {
1580 add_uses_to_worklist(use);
1581 if (use->arraycopy_dst()) {
1582 for (EdgeIterator i(use); i.has_next(); i.next()) {
1583 PointsToNode* e = i.get();
1584 if (e->is_Arraycopy()) {
1585 if (jobj == null_obj) { // NULL object does not have field edges
1586 continue;
1587 }
1588 // Add edge from arraycopy's destination java object to Arraycopy node.
1589 if (add_edge(jobj, e)) {
1590 new_edges++;
1591 jobj->set_arraycopy_dst();
1592 }
1593 }
1594 }
1595 }
1596 } else {
1597 // Added new edge to stored in field values.
1598 // Put on worklist all field's uses (loads) and
1599 // related field nodes (same base and offset).
1600 add_field_uses_to_worklist(use->as_Field());
1601 }
1602 }
1603 _worklist.clear();
1604 _in_worklist.reset();
1605 return new_edges;
1606 }
1607
1608 // Put on worklist all related field nodes.
1609 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) {
1610 assert(field->is_oop(), "sanity");
1611 int offset = field->offset();
1612 add_uses_to_worklist(field);
1613 // Loop over all bases of this field and push on worklist Field nodes
1614 // with the same offset and base (since they may reference the same field).
1615 for (BaseIterator i(field); i.has_next(); i.next()) {
1616 PointsToNode* base = i.get();
1617 add_fields_to_worklist(field, base);
1618 // Check if the base was source object of arraycopy and go over arraycopy's
1619 // destination objects since values stored to a field of source object are
1620 // accessible by uses (loads) of fields of destination objects.
1621 if (base->arraycopy_src()) {
1622 for (UseIterator j(base); j.has_next(); j.next()) {
1623 PointsToNode* arycp = j.get();
1624 if (arycp->is_Arraycopy()) {
1625 for (UseIterator k(arycp); k.has_next(); k.next()) {
1626 PointsToNode* abase = k.get();
1627 if (abase->arraycopy_dst() && abase != base) {
1628 // Look for the same arraycopy reference.
1629 add_fields_to_worklist(field, abase);
1630 }
1631 }
1632 }
1633 }
1634 }
1635 }
1636 }
1637
1638 // Put on worklist all related field nodes.
1639 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) {
1640 int offset = field->offset();
1641 if (base->is_LocalVar()) {
1642 for (UseIterator j(base); j.has_next(); j.next()) {
1643 PointsToNode* f = j.get();
1644 if (PointsToNode::is_base_use(f)) { // Field
1645 f = PointsToNode::get_use_node(f);
1646 if (f == field || !f->as_Field()->is_oop()) {
1647 continue;
1648 }
1649 int offs = f->as_Field()->offset();
1650 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1651 add_to_worklist(f);
1652 }
1653 }
1654 }
1655 } else {
1656 assert(base->is_JavaObject(), "sanity");
1657 if (// Skip phantom_object since it is only used to indicate that
1658 // this field's content globally escapes.
1659 (base != phantom_obj) &&
1660 // NULL object node does not have fields.
1661 (base != null_obj)) {
1662 for (EdgeIterator i(base); i.has_next(); i.next()) {
1663 PointsToNode* f = i.get();
1664 // Skip arraycopy edge since store to destination object field
1665 // does not update value in source object field.
1666 if (f->is_Arraycopy()) {
1667 assert(base->arraycopy_dst(), "sanity");
1668 continue;
1669 }
1670 if (f == field || !f->as_Field()->is_oop()) {
1671 continue;
1672 }
1673 int offs = f->as_Field()->offset();
1674 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1675 add_to_worklist(f);
1676 }
1677 }
1678 }
1679 }
1680 }
1681
1682 // Find fields which have unknown value.
1683 int ConnectionGraph::find_field_value(FieldNode* field) {
1684 // Escaped fields should have init value already.
1685 assert(field->escape_state() == PointsToNode::NoEscape, "sanity");
1686 int new_edges = 0;
1687 for (BaseIterator i(field); i.has_next(); i.next()) {
1688 PointsToNode* base = i.get();
1689 if (base->is_JavaObject()) {
1690 // Skip Allocate's fields which will be processed later.
1691 if (base->ideal_node()->is_Allocate()) {
1692 return 0;
1693 }
1694 assert(base == null_obj, "only NULL ptr base expected here");
1695 }
1696 }
1697 if (add_edge(field, phantom_obj)) {
1698 // New edge was added
1699 new_edges++;
1700 add_field_uses_to_worklist(field);
1701 }
1702 return new_edges;
1703 }
1704
1705 // Find fields initializing values for allocations.
1706 int ConnectionGraph::find_init_values_phantom(JavaObjectNode* pta) {
1707 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
1708 Node* alloc = pta->ideal_node();
1709
1710 // Do nothing for Allocate nodes since its fields values are
1711 // "known" unless they are initialized by arraycopy/clone.
1712 if (alloc->is_Allocate() && !pta->arraycopy_dst()) {
1713 return 0;
1714 }
1715 assert(pta->arraycopy_dst() || alloc->as_CallStaticJava(), "sanity");
1716 #ifdef ASSERT
1717 if (!pta->arraycopy_dst() && alloc->as_CallStaticJava()->method() == NULL) {
1718 const char* name = alloc->as_CallStaticJava()->_name;
1719 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity");
1720 }
1721 #endif
1722 // Non-escaped allocation returned from Java or runtime call have unknown values in fields.
1723 int new_edges = 0;
1724 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1725 PointsToNode* field = i.get();
1726 if (field->is_Field() && field->as_Field()->is_oop()) {
1727 if (add_edge(field, phantom_obj)) {
1728 // New edge was added
1729 new_edges++;
1730 add_field_uses_to_worklist(field->as_Field());
1731 }
1732 }
1733 }
1734 return new_edges;
1735 }
1736
1737 // Find fields initializing values for allocations.
1738 int ConnectionGraph::find_init_values_null(JavaObjectNode* pta, PhaseTransform* phase) {
1739 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
1740 Node* alloc = pta->ideal_node();
1741 // Do nothing for Call nodes since its fields values are unknown.
1742 if (!alloc->is_Allocate()) {
1743 return 0;
1744 }
1745 InitializeNode* ini = alloc->as_Allocate()->initialization();
1746 bool visited_bottom_offset = false;
1747 GrowableArray<int> offsets_worklist;
1748 int new_edges = 0;
1749
1750 // Check if an oop field's initializing value is recorded and add
1751 // a corresponding NULL if field's value if it is not recorded.
1752 // Connection Graph does not record a default initialization by NULL
1753 // captured by Initialize node.
1754 //
1755 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1756 PointsToNode* field = i.get(); // Field (AddP)
1757 if (!field->is_Field() || !field->as_Field()->is_oop()) {
1758 continue; // Not oop field
1759 }
1760 int offset = field->as_Field()->offset();
1761 if (offset == Type::OffsetBot) {
1762 if (!visited_bottom_offset) {
1763 // OffsetBot is used to reference array's element,
1764 // always add reference to NULL to all Field nodes since we don't
1765 // known which element is referenced.
1766 if (add_edge(field, null_obj)) {
1767 // New edge was added
1768 new_edges++;
1769 add_field_uses_to_worklist(field->as_Field());
1770 visited_bottom_offset = true;
1771 }
1772 }
1773 } else {
1774 // Check only oop fields.
1775 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type();
1776 if (adr_type->isa_rawptr()) {
1777 #ifdef ASSERT
1778 // Raw pointers are used for initializing stores so skip it
1779 // since it should be recorded already
1780 Node* base = get_addp_base(field->ideal_node());
1781 assert(adr_type->isa_rawptr() && is_captured_store_address(field->ideal_node()), "unexpected pointer type");
1782 #endif
1783 continue;
1784 }
1785 if (!offsets_worklist.contains(offset)) {
1786 offsets_worklist.append(offset);
1787 Node* value = NULL;
1788 if (ini != NULL) {
1789 // StoreP::memory_type() == T_ADDRESS
1790 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS;
1791 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase);
1792 // Make sure initializing store has the same type as this AddP.
1793 // This AddP may reference non existing field because it is on a
1794 // dead branch of bimorphic call which is not eliminated yet.
1795 if (store != NULL && store->is_Store() &&
1796 store->as_Store()->memory_type() == ft) {
1797 value = store->in(MemNode::ValueIn);
1798 #ifdef ASSERT
1799 if (VerifyConnectionGraph) {
1800 // Verify that AddP already points to all objects the value points to.
1801 PointsToNode* val = ptnode_adr(value->_idx);
1802 assert((val != NULL), "should be processed already");
1803 PointsToNode* missed_obj = NULL;
1804 if (val->is_JavaObject()) {
1805 if (!field->points_to(val->as_JavaObject())) {
1806 missed_obj = val;
1807 }
1808 } else {
1809 if (!val->is_LocalVar() || (val->edge_count() == 0)) {
1810 tty->print_cr("----------init store has invalid value -----");
1811 store->dump();
1812 val->dump();
1813 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already");
1814 }
1815 for (EdgeIterator j(val); j.has_next(); j.next()) {
1816 PointsToNode* obj = j.get();
1817 if (obj->is_JavaObject()) {
1818 if (!field->points_to(obj->as_JavaObject())) {
1819 missed_obj = obj;
1820 break;
1821 }
1822 }
1823 }
1824 }
1825 if (missed_obj != NULL) {
1826 tty->print_cr("----------field---------------------------------");
1827 field->dump();
1828 tty->print_cr("----------missed referernce to object-----------");
1829 missed_obj->dump();
1830 tty->print_cr("----------object referernced by init store -----");
1831 store->dump();
1832 val->dump();
1833 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference");
1834 }
1835 }
1836 #endif
1837 } else {
1838 // There could be initializing stores which follow allocation.
1839 // For example, a volatile field store is not collected
1840 // by Initialize node.
1841 //
1842 // Need to check for dependent loads to separate such stores from
1843 // stores which follow loads. For now, add initial value NULL so
1844 // that compare pointers optimization works correctly.
1845 }
1846 }
1847 if (value == NULL) {
1848 // A field's initializing value was not recorded. Add NULL.
1849 if (add_edge(field, null_obj)) {
1850 // New edge was added
1851 new_edges++;
1852 add_field_uses_to_worklist(field->as_Field());
1853 }
1854 }
1855 }
1856 }
1857 }
1858 return new_edges;
1859 }
1860
1861 // Adjust scalar_replaceable state after Connection Graph is built.
1862 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) {
1863 // Search for non-escaping objects which are not scalar replaceable
1864 // and mark them to propagate the state to referenced objects.
1865
1866 for (UseIterator i(jobj); i.has_next(); i.next()) {
1867 PointsToNode* use = i.get();
1868 if (use->is_Arraycopy()) {
1869 continue;
1870 }
1871 if (use->is_Field()) {
1872 FieldNode* field = use->as_Field();
1873 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
1874 // 1. An object is not scalar replaceable if the field into which it is
1875 // stored has unknown offset (stored into unknown element of an array).
1876 if (field->offset() == Type::OffsetBot) {
1877 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored at unknown offset"));
1878 return;
1879 }
1880 for (BaseIterator i(field); i.has_next(); i.next()) {
1881 PointsToNode* base = i.get();
1882 // 2. An object is not scalar replaceable if the field into which it is
1883 // stored has multiple bases one of which is null.
1884 if ((base == null_obj) && (field->base_count() > 1)) {
1885 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with potentially null base"));
1886 return;
1887 }
1888 // 2.5. An object is not scalar replaceable if the field into which it is
1889 // stored has NSR base.
1890 if (!base->scalar_replaceable()) {
1891 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with NSR base"));
1892 return;
1893 }
1894 }
1895 }
1896 assert(use->is_Field() || use->is_LocalVar(), "sanity");
1897 // 3. An object is not scalar replaceable if it is merged with other objects.
1898 for (EdgeIterator j(use); j.has_next(); j.next()) {
1899 PointsToNode* ptn = j.get();
1900 if (ptn->is_JavaObject() && ptn != jobj) {
1901 // Mark all objects.
1902 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA trace_merged_message(ptn)));
1903 set_not_scalar_replaceable(ptn NOT_PRODUCT(COMMA trace_merged_message(jobj)));
1904 }
1905 }
1906 if (!jobj->scalar_replaceable()) {
1907 return;
1908 }
1909 }
1910
1911 for (EdgeIterator j(jobj); j.has_next(); j.next()) {
1912 if (j.get()->is_Arraycopy()) {
1913 continue;
1914 }
1915
1916 // Non-escaping object node should point only to field nodes.
1917 FieldNode* field = j.get()->as_Field();
1918 int offset = field->as_Field()->offset();
1919
1920 // 4. An object is not scalar replaceable if it has a field with unknown
1921 // offset (array's element is accessed in loop).
1922 if (offset == Type::OffsetBot) {
1923 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "has field with unknown offset"));
1924 return;
1925 }
1926 // 5. Currently an object is not scalar replaceable if a LoadStore node
1927 // access its field since the field value is unknown after it.
1928 //
1929 Node* n = field->ideal_node();
1930
1931 // Test for an unsafe access that was parsed as maybe off heap
1932 // (with a CheckCastPP to raw memory).
1933 assert(n->is_AddP(), "expect an address computation");
1934 if (n->in(AddPNode::Base)->is_top() &&
1935 n->in(AddPNode::Address)->Opcode() == Op_CheckCastPP) {
1936 assert(n->in(AddPNode::Address)->bottom_type()->isa_rawptr(), "raw address so raw cast expected");
1937 assert(_igvn->type(n->in(AddPNode::Address)->in(1))->isa_oopptr(), "cast pattern at unsafe access expected");
1938 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is used as base of mixed unsafe access"));
1939 return;
1940 }
1941
1942 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1943 Node* u = n->fast_out(i);
1944 if (u->is_LoadStore() || (u->is_Mem() && u->as_Mem()->is_mismatched_access())) {
1945 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is used in LoadStore or mismatched access"));
1946 return;
1947 }
1948 }
1949
1950 // 6. Or the address may point to more then one object. This may produce
1951 // the false positive result (set not scalar replaceable)
1952 // since the flow-insensitive escape analysis can't separate
1953 // the case when stores overwrite the field's value from the case
1954 // when stores happened on different control branches.
1955 //
1956 // Note: it will disable scalar replacement in some cases:
1957 //
1958 // Point p[] = new Point[1];
1959 // p[0] = new Point(); // Will be not scalar replaced
1960 //
1961 // but it will save us from incorrect optimizations in next cases:
1962 //
1963 // Point p[] = new Point[1];
1964 // if ( x ) p[0] = new Point(); // Will be not scalar replaced
1965 //
1966 if (field->base_count() > 1) {
1967 for (BaseIterator i(field); i.has_next(); i.next()) {
1968 PointsToNode* base = i.get();
1969 // Don't take into account LocalVar nodes which
1970 // may point to only one object which should be also
1971 // this field's base by now.
1972 if (base->is_JavaObject() && base != jobj) {
1973 // Mark all bases.
1974 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "may point to more than one object"));
1975 set_not_scalar_replaceable(base NOT_PRODUCT(COMMA "may point to more than one object"));
1976 }
1977 }
1978 }
1979 }
1980 }
1981
1982 // Propagate NSR (Not scalar replaceable) state.
1983 void ConnectionGraph::find_scalar_replaceable_allocs(GrowableArray<JavaObjectNode*>& jobj_worklist) {
1984 int jobj_length = jobj_worklist.length();
1985 bool found_nsr_alloc = true;
1986 while (found_nsr_alloc) {
1987 found_nsr_alloc = false;
1988 for (int next = 0; next < jobj_length; ++next) {
1989 JavaObjectNode* jobj = jobj_worklist.at(next);
1990 for (UseIterator i(jobj); (jobj->scalar_replaceable() && i.has_next()); i.next()) {
1991 PointsToNode* use = i.get();
1992 if (use->is_Field()) {
1993 FieldNode* field = use->as_Field();
1994 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
1995 assert(field->offset() != Type::OffsetBot, "sanity");
1996 for (BaseIterator i(field); i.has_next(); i.next()) {
1997 PointsToNode* base = i.get();
1998 // An object is not scalar replaceable if the field into which
1999 // it is stored has NSR base.
2000 if ((base != null_obj) && !base->scalar_replaceable()) {
2001 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with NSR base"));
2002 found_nsr_alloc = true;
2003 break;
2004 }
2005 }
2006 }
2007 }
2008 }
2009 }
2010 }
2011
2012 #ifdef ASSERT
2013 void ConnectionGraph::verify_connection_graph(
2014 GrowableArray<PointsToNode*>& ptnodes_worklist,
2015 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist,
2016 GrowableArray<JavaObjectNode*>& java_objects_worklist,
2017 GrowableArray<Node*>& addp_worklist) {
2018 // Verify that graph is complete - no new edges could be added.
2019 int java_objects_length = java_objects_worklist.length();
2020 int non_escaped_length = non_escaped_allocs_worklist.length();
2021 int new_edges = 0;
2022 for (int next = 0; next < java_objects_length; ++next) {
2023 JavaObjectNode* ptn = java_objects_worklist.at(next);
2024 new_edges += add_java_object_edges(ptn, true);
2025 }
2026 assert(new_edges == 0, "graph was not complete");
2027 // Verify that escape state is final.
2028 int length = non_escaped_allocs_worklist.length();
2029 find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist);
2030 assert((non_escaped_length == non_escaped_allocs_worklist.length()) &&
2031 (non_escaped_length == length) &&
2032 (_worklist.length() == 0), "escape state was not final");
2033
2034 // Verify fields information.
2035 int addp_length = addp_worklist.length();
2036 for (int next = 0; next < addp_length; ++next ) {
2037 Node* n = addp_worklist.at(next);
2038 FieldNode* field = ptnode_adr(n->_idx)->as_Field();
2039 if (field->is_oop()) {
2040 // Verify that field has all bases
2041 Node* base = get_addp_base(n);
2042 PointsToNode* ptn = ptnode_adr(base->_idx);
2043 if (ptn->is_JavaObject()) {
2044 assert(field->has_base(ptn->as_JavaObject()), "sanity");
2045 } else {
2046 assert(ptn->is_LocalVar(), "sanity");
2047 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2048 PointsToNode* e = i.get();
2049 if (e->is_JavaObject()) {
2050 assert(field->has_base(e->as_JavaObject()), "sanity");
2051 }
2052 }
2053 }
2054 // Verify that all fields have initializing values.
2055 if (field->edge_count() == 0) {
2056 tty->print_cr("----------field does not have references----------");
2057 field->dump();
2058 for (BaseIterator i(field); i.has_next(); i.next()) {
2059 PointsToNode* base = i.get();
2060 tty->print_cr("----------field has next base---------------------");
2061 base->dump();
2062 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) {
2063 tty->print_cr("----------base has fields-------------------------");
2064 for (EdgeIterator j(base); j.has_next(); j.next()) {
2065 j.get()->dump();
2066 }
2067 tty->print_cr("----------base has references---------------------");
2068 for (UseIterator j(base); j.has_next(); j.next()) {
2069 j.get()->dump();
2070 }
2071 }
2072 }
2073 for (UseIterator i(field); i.has_next(); i.next()) {
2074 i.get()->dump();
2075 }
2076 assert(field->edge_count() > 0, "sanity");
2077 }
2078 }
2079 }
2080 }
2081 #endif
2082
2083 // Optimize ideal graph.
2084 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist,
2085 GrowableArray<MemBarStoreStoreNode*>& storestore_worklist) {
2086 Compile* C = _compile;
2087 PhaseIterGVN* igvn = _igvn;
2088 if (EliminateLocks) {
2089 // Mark locks before changing ideal graph.
2090 int cnt = C->macro_count();
2091 for (int i = 0; i < cnt; i++) {
2092 Node *n = C->macro_node(i);
2093 if (n->is_AbstractLock()) { // Lock and Unlock nodes
2094 AbstractLockNode* alock = n->as_AbstractLock();
2095 if (!alock->is_non_esc_obj()) {
2096 if (not_global_escape(alock->obj_node())) {
2097 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity");
2098 // The lock could be marked eliminated by lock coarsening
2099 // code during first IGVN before EA. Replace coarsened flag
2100 // to eliminate all associated locks/unlocks.
2101 #ifdef ASSERT
2102 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3");
2103 #endif
2104 alock->set_non_esc_obj();
2105 }
2106 }
2107 }
2108 }
2109 }
2110
2111 if (OptimizePtrCompare) {
2112 for (int i = 0; i < ptr_cmp_worklist.length(); i++) {
2113 Node *n = ptr_cmp_worklist.at(i);
2114 const TypeInt* tcmp = optimize_ptr_compare(n);
2115 if (tcmp->singleton()) {
2116 Node* cmp = igvn->makecon(tcmp);
2117 #ifndef PRODUCT
2118 if (PrintOptimizePtrCompare) {
2119 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, (tcmp == TypeInt::CC_EQ ? "EQ" : "NotEQ"));
2120 if (Verbose) {
2121 n->dump(1);
2122 }
2123 }
2124 #endif
2125 igvn->replace_node(n, cmp);
2126 }
2127 }
2128 }
2129
2130 // For MemBarStoreStore nodes added in library_call.cpp, check
2131 // escape status of associated AllocateNode and optimize out
2132 // MemBarStoreStore node if the allocated object never escapes.
2133 for (int i = 0; i < storestore_worklist.length(); i++) {
2134 Node* storestore = storestore_worklist.at(i);
2135 Node* alloc = storestore->in(MemBarNode::Precedent)->in(0);
2136 if (alloc->is_Allocate() && not_global_escape(alloc)) {
2137 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot);
2138 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory));
2139 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control));
2140 igvn->register_new_node_with_optimizer(mb);
2141 igvn->replace_node(storestore, mb);
2142 }
2143 }
2144 }
2145
2146 // Optimize objects compare.
2147 const TypeInt* ConnectionGraph::optimize_ptr_compare(Node* n) {
2148 assert(OptimizePtrCompare, "sanity");
2149 assert(n->Opcode() == Op_CmpN || n->Opcode() == Op_CmpP, "must be");
2150 const TypeInt* EQ = TypeInt::CC_EQ; // [0] == ZERO
2151 const TypeInt* NE = TypeInt::CC_GT; // [1] == ONE
2152 const TypeInt* UNKNOWN = TypeInt::CC; // [-1, 0,1]
2153
2154 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx);
2155 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx);
2156 JavaObjectNode* jobj1 = unique_java_object(n->in(1));
2157 JavaObjectNode* jobj2 = unique_java_object(n->in(2));
2158 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity");
2159 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity");
2160
2161 // Check simple cases first.
2162 if (jobj1 != NULL) {
2163 if (jobj1->escape_state() == PointsToNode::NoEscape) {
2164 if (jobj1 == jobj2) {
2165 // Comparing the same not escaping object.
2166 return EQ;
2167 }
2168 Node* obj = jobj1->ideal_node();
2169 // Comparing not escaping allocation.
2170 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
2171 !ptn2->points_to(jobj1)) {
2172 return NE; // This includes nullness check.
2173 }
2174 }
2175 }
2176 if (jobj2 != NULL) {
2177 if (jobj2->escape_state() == PointsToNode::NoEscape) {
2178 Node* obj = jobj2->ideal_node();
2179 // Comparing not escaping allocation.
2180 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
2181 !ptn1->points_to(jobj2)) {
2182 return NE; // This includes nullness check.
2183 }
2184 }
2185 }
2186 if (jobj1 != NULL && jobj1 != phantom_obj &&
2187 jobj2 != NULL && jobj2 != phantom_obj &&
2188 jobj1->ideal_node()->is_Con() &&
2189 jobj2->ideal_node()->is_Con()) {
2190 // Klass or String constants compare. Need to be careful with
2191 // compressed pointers - compare types of ConN and ConP instead of nodes.
2192 const Type* t1 = jobj1->ideal_node()->get_ptr_type();
2193 const Type* t2 = jobj2->ideal_node()->get_ptr_type();
2194 if (t1->make_ptr() == t2->make_ptr()) {
2195 return EQ;
2196 } else {
2197 return NE;
2198 }
2199 }
2200 if (ptn1->meet(ptn2)) {
2201 return UNKNOWN; // Sets are not disjoint
2202 }
2203
2204 // Sets are disjoint.
2205 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj);
2206 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj);
2207 bool set1_has_null_ptr = ptn1->points_to(null_obj);
2208 bool set2_has_null_ptr = ptn2->points_to(null_obj);
2209 if ((set1_has_unknown_ptr && set2_has_null_ptr) ||
2210 (set2_has_unknown_ptr && set1_has_null_ptr)) {
2211 // Check nullness of unknown object.
2212 return UNKNOWN;
2213 }
2214
2215 // Disjointness by itself is not sufficient since
2216 // alias analysis is not complete for escaped objects.
2217 // Disjoint sets are definitely unrelated only when
2218 // at least one set has only not escaping allocations.
2219 if (!set1_has_unknown_ptr && !set1_has_null_ptr) {
2220 if (ptn1->non_escaping_allocation()) {
2221 return NE;
2222 }
2223 }
2224 if (!set2_has_unknown_ptr && !set2_has_null_ptr) {
2225 if (ptn2->non_escaping_allocation()) {
2226 return NE;
2227 }
2228 }
2229 return UNKNOWN;
2230 }
2231
2232 // Connection Graph construction functions.
2233
2234 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) {
2235 PointsToNode* ptadr = _nodes.at(n->_idx);
2236 if (ptadr != NULL) {
2237 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity");
2238 return;
2239 }
2240 Compile* C = _compile;
2241 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es);
2242 map_ideal_node(n, ptadr);
2243 }
2244
2245 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) {
2246 PointsToNode* ptadr = _nodes.at(n->_idx);
2247 if (ptadr != NULL) {
2248 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity");
2249 return;
2250 }
2251 Compile* C = _compile;
2252 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es);
2253 map_ideal_node(n, ptadr);
2254 }
2255
2256 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) {
2257 PointsToNode* ptadr = _nodes.at(n->_idx);
2258 if (ptadr != NULL) {
2259 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity");
2260 return;
2261 }
2262 bool unsafe = false;
2263 bool is_oop = is_oop_field(n, offset, &unsafe);
2264 if (unsafe) {
2265 es = PointsToNode::GlobalEscape;
2266 }
2267 Compile* C = _compile;
2268 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop);
2269 map_ideal_node(n, field);
2270 }
2271
2272 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es,
2273 PointsToNode* src, PointsToNode* dst) {
2274 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar");
2275 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL");
2276 PointsToNode* ptadr = _nodes.at(n->_idx);
2277 if (ptadr != NULL) {
2278 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity");
2279 return;
2280 }
2281 Compile* C = _compile;
2282 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es);
2283 map_ideal_node(n, ptadr);
2284 // Add edge from arraycopy node to source object.
2285 (void)add_edge(ptadr, src);
2286 src->set_arraycopy_src();
2287 // Add edge from destination object to arraycopy node.
2288 (void)add_edge(dst, ptadr);
2289 dst->set_arraycopy_dst();
2290 }
2291
2292 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) {
2293 const Type* adr_type = n->as_AddP()->bottom_type();
2294 BasicType bt = T_INT;
2295 if (offset == Type::OffsetBot) {
2296 // Check only oop fields.
2297 if (!adr_type->isa_aryptr() ||
2298 adr_type->isa_aryptr()->elem() == Type::BOTTOM ||
2299 adr_type->isa_aryptr()->elem()->make_oopptr() != NULL) {
2300 // OffsetBot is used to reference array's element. Ignore first AddP.
2301 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) {
2302 bt = T_OBJECT;
2303 }
2304 }
2305 } else if (offset != oopDesc::klass_offset_in_bytes()) {
2306 if (adr_type->isa_instptr()) {
2307 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field();
2308 if (field != NULL) {
2309 bt = field->layout_type();
2310 } else {
2311 // Check for unsafe oop field access
2312 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2313 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2314 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN) ||
2315 BarrierSet::barrier_set()->barrier_set_c2()->escape_has_out_with_unsafe_object(n)) {
2316 bt = T_OBJECT;
2317 (*unsafe) = true;
2318 }
2319 }
2320 } else if (adr_type->isa_aryptr()) {
2321 if (offset == arrayOopDesc::length_offset_in_bytes()) {
2322 // Ignore array length load.
2323 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) {
2324 // Ignore first AddP.
2325 } else {
2326 const Type* elemtype = adr_type->isa_aryptr()->elem();
2327 bt = elemtype->array_element_basic_type();
2328 }
2329 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) {
2330 // Allocation initialization, ThreadLocal field access, unsafe access
2331 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2332 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2333 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN) ||
2334 BarrierSet::barrier_set()->barrier_set_c2()->escape_has_out_with_unsafe_object(n)) {
2335 bt = T_OBJECT;
2336 }
2337 }
2338 }
2339 // Note: T_NARROWOOP is not classed as a real reference type
2340 return (is_reference_type(bt) || bt == T_NARROWOOP);
2341 }
2342
2343 // Returns unique pointed java object or NULL.
2344 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) {
2345 assert(!_collecting, "should not call when constructed graph");
2346 // If the node was created after the escape computation we can't answer.
2347 uint idx = n->_idx;
2348 if (idx >= nodes_size()) {
2349 return NULL;
2350 }
2351 PointsToNode* ptn = ptnode_adr(idx);
2352 if (ptn == NULL) {
2353 return NULL;
2354 }
2355 if (ptn->is_JavaObject()) {
2356 return ptn->as_JavaObject();
2357 }
2358 assert(ptn->is_LocalVar(), "sanity");
2359 // Check all java objects it points to.
2360 JavaObjectNode* jobj = NULL;
2361 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2362 PointsToNode* e = i.get();
2363 if (e->is_JavaObject()) {
2364 if (jobj == NULL) {
2365 jobj = e->as_JavaObject();
2366 } else if (jobj != e) {
2367 return NULL;
2368 }
2369 }
2370 }
2371 return jobj;
2372 }
2373
2374 // Return true if this node points only to non-escaping allocations.
2375 bool PointsToNode::non_escaping_allocation() {
2376 if (is_JavaObject()) {
2377 Node* n = ideal_node();
2378 if (n->is_Allocate() || n->is_CallStaticJava()) {
2379 return (escape_state() == PointsToNode::NoEscape);
2380 } else {
2381 return false;
2382 }
2383 }
2384 assert(is_LocalVar(), "sanity");
2385 // Check all java objects it points to.
2386 for (EdgeIterator i(this); i.has_next(); i.next()) {
2387 PointsToNode* e = i.get();
2388 if (e->is_JavaObject()) {
2389 Node* n = e->ideal_node();
2390 if ((e->escape_state() != PointsToNode::NoEscape) ||
2391 !(n->is_Allocate() || n->is_CallStaticJava())) {
2392 return false;
2393 }
2394 }
2395 }
2396 return true;
2397 }
2398
2399 // Return true if we know the node does not escape globally.
2400 bool ConnectionGraph::not_global_escape(Node *n) {
2401 assert(!_collecting, "should not call during graph construction");
2402 // If the node was created after the escape computation we can't answer.
2403 uint idx = n->_idx;
2404 if (idx >= nodes_size()) {
2405 return false;
2406 }
2407 PointsToNode* ptn = ptnode_adr(idx);
2408 if (ptn == NULL) {
2409 return false; // not in congraph (e.g. ConI)
2410 }
2411 PointsToNode::EscapeState es = ptn->escape_state();
2412 // If we have already computed a value, return it.
2413 if (es >= PointsToNode::GlobalEscape) {
2414 return false;
2415 }
2416 if (ptn->is_JavaObject()) {
2417 return true; // (es < PointsToNode::GlobalEscape);
2418 }
2419 assert(ptn->is_LocalVar(), "sanity");
2420 // Check all java objects it points to.
2421 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2422 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) {
2423 return false;
2424 }
2425 }
2426 return true;
2427 }
2428
2429
2430 // Helper functions
2431
2432 // Return true if this node points to specified node or nodes it points to.
2433 bool PointsToNode::points_to(JavaObjectNode* ptn) const {
2434 if (is_JavaObject()) {
2435 return (this == ptn);
2436 }
2437 assert(is_LocalVar() || is_Field(), "sanity");
2438 for (EdgeIterator i(this); i.has_next(); i.next()) {
2439 if (i.get() == ptn) {
2440 return true;
2441 }
2442 }
2443 return false;
2444 }
2445
2446 // Return true if one node points to an other.
2447 bool PointsToNode::meet(PointsToNode* ptn) {
2448 if (this == ptn) {
2449 return true;
2450 } else if (ptn->is_JavaObject()) {
2451 return this->points_to(ptn->as_JavaObject());
2452 } else if (this->is_JavaObject()) {
2453 return ptn->points_to(this->as_JavaObject());
2454 }
2455 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity");
2456 int ptn_count = ptn->edge_count();
2457 for (EdgeIterator i(this); i.has_next(); i.next()) {
2458 PointsToNode* this_e = i.get();
2459 for (int j = 0; j < ptn_count; j++) {
2460 if (this_e == ptn->edge(j)) {
2461 return true;
2462 }
2463 }
2464 }
2465 return false;
2466 }
2467
2468 #ifdef ASSERT
2469 // Return true if bases point to this java object.
2470 bool FieldNode::has_base(JavaObjectNode* jobj) const {
2471 for (BaseIterator i(this); i.has_next(); i.next()) {
2472 if (i.get() == jobj) {
2473 return true;
2474 }
2475 }
2476 return false;
2477 }
2478 #endif
2479
2480 bool ConnectionGraph::is_captured_store_address(Node* addp) {
2481 // Handle simple case first.
2482 assert(_igvn->type(addp)->isa_oopptr() == NULL, "should be raw access");
2483 if (addp->in(AddPNode::Address)->is_Proj() && addp->in(AddPNode::Address)->in(0)->is_Allocate()) {
2484 return true;
2485 } else if (addp->in(AddPNode::Address)->is_Phi()) {
2486 for (DUIterator_Fast imax, i = addp->fast_outs(imax); i < imax; i++) {
2487 Node* addp_use = addp->fast_out(i);
2488 if (addp_use->is_Store()) {
2489 for (DUIterator_Fast jmax, j = addp_use->fast_outs(jmax); j < jmax; j++) {
2490 if (addp_use->fast_out(j)->is_Initialize()) {
2491 return true;
2492 }
2493 }
2494 }
2495 }
2496 }
2497 return false;
2498 }
2499
2500 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
2501 const Type *adr_type = phase->type(adr);
2502 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL && is_captured_store_address(adr)) {
2503 // We are computing a raw address for a store captured by an Initialize
2504 // compute an appropriate address type. AddP cases #3 and #5 (see below).
2505 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
2506 assert(offs != Type::OffsetBot ||
2507 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
2508 "offset must be a constant or it is initialization of array");
2509 return offs;
2510 }
2511 const TypePtr *t_ptr = adr_type->isa_ptr();
2512 assert(t_ptr != NULL, "must be a pointer type");
2513 return t_ptr->offset();
2514 }
2515
2516 Node* ConnectionGraph::get_addp_base(Node *addp) {
2517 assert(addp->is_AddP(), "must be AddP");
2518 //
2519 // AddP cases for Base and Address inputs:
2520 // case #1. Direct object's field reference:
2521 // Allocate
2522 // |
2523 // Proj #5 ( oop result )
2524 // |
2525 // CheckCastPP (cast to instance type)
2526 // | |
2527 // AddP ( base == address )
2528 //
2529 // case #2. Indirect object's field reference:
2530 // Phi
2531 // |
2532 // CastPP (cast to instance type)
2533 // | |
2534 // AddP ( base == address )
2535 //
2536 // case #3. Raw object's field reference for Initialize node:
2537 // Allocate
2538 // |
2539 // Proj #5 ( oop result )
2540 // top |
2541 // \ |
2542 // AddP ( base == top )
2543 //
2544 // case #4. Array's element reference:
2545 // {CheckCastPP | CastPP}
2546 // | | |
2547 // | AddP ( array's element offset )
2548 // | |
2549 // AddP ( array's offset )
2550 //
2551 // case #5. Raw object's field reference for arraycopy stub call:
2552 // The inline_native_clone() case when the arraycopy stub is called
2553 // after the allocation before Initialize and CheckCastPP nodes.
2554 // Allocate
2555 // |
2556 // Proj #5 ( oop result )
2557 // | |
2558 // AddP ( base == address )
2559 //
2560 // case #6. Constant Pool, ThreadLocal, CastX2P or
2561 // Raw object's field reference:
2562 // {ConP, ThreadLocal, CastX2P, raw Load}
2563 // top |
2564 // \ |
2565 // AddP ( base == top )
2566 //
2567 // case #7. Klass's field reference.
2568 // LoadKlass
2569 // | |
2570 // AddP ( base == address )
2571 //
2572 // case #8. narrow Klass's field reference.
2573 // LoadNKlass
2574 // |
2575 // DecodeN
2576 // | |
2577 // AddP ( base == address )
2578 //
2579 // case #9. Mixed unsafe access
2580 // {instance}
2581 // |
2582 // CheckCastPP (raw)
2583 // top |
2584 // \ |
2585 // AddP ( base == top )
2586 //
2587 Node *base = addp->in(AddPNode::Base);
2588 if (base->uncast()->is_top()) { // The AddP case #3 and #6 and #9.
2589 base = addp->in(AddPNode::Address);
2590 while (base->is_AddP()) {
2591 // Case #6 (unsafe access) may have several chained AddP nodes.
2592 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only");
2593 base = base->in(AddPNode::Address);
2594 }
2595 if (base->Opcode() == Op_CheckCastPP &&
2596 base->bottom_type()->isa_rawptr() &&
2597 _igvn->type(base->in(1))->isa_oopptr()) {
2598 base = base->in(1); // Case #9
2599 } else {
2600 Node* uncast_base = base->uncast();
2601 int opcode = uncast_base->Opcode();
2602 assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
2603 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
2604 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) ||
2605 is_captured_store_address(addp), "sanity");
2606 }
2607 }
2608 return base;
2609 }
2610
2611 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) {
2612 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
2613 Node* addp2 = addp->raw_out(0);
2614 if (addp->outcnt() == 1 && addp2->is_AddP() &&
2615 addp2->in(AddPNode::Base) == n &&
2616 addp2->in(AddPNode::Address) == addp) {
2617 assert(addp->in(AddPNode::Base) == n, "expecting the same base");
2618 //
2619 // Find array's offset to push it on worklist first and
2620 // as result process an array's element offset first (pushed second)
2621 // to avoid CastPP for the array's offset.
2622 // Otherwise the inserted CastPP (LocalVar) will point to what
2623 // the AddP (Field) points to. Which would be wrong since
2624 // the algorithm expects the CastPP has the same point as
2625 // as AddP's base CheckCastPP (LocalVar).
2626 //
2627 // ArrayAllocation
2628 // |
2629 // CheckCastPP
2630 // |
2631 // memProj (from ArrayAllocation CheckCastPP)
2632 // | ||
2633 // | || Int (element index)
2634 // | || | ConI (log(element size))
2635 // | || | /
2636 // | || LShift
2637 // | || /
2638 // | AddP (array's element offset)
2639 // | |
2640 // | | ConI (array's offset: #12(32-bits) or #24(64-bits))
2641 // | / /
2642 // AddP (array's offset)
2643 // |
2644 // Load/Store (memory operation on array's element)
2645 //
2646 return addp2;
2647 }
2648 return NULL;
2649 }
2650
2651 //
2652 // Adjust the type and inputs of an AddP which computes the
2653 // address of a field of an instance
2654 //
2655 bool ConnectionGraph::split_AddP(Node *addp, Node *base) {
2656 PhaseGVN* igvn = _igvn;
2657 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
2658 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
2659 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
2660 if (t == NULL) {
2661 // We are computing a raw address for a store captured by an Initialize
2662 // compute an appropriate address type (cases #3 and #5).
2663 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
2664 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
2665 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
2666 assert(offs != Type::OffsetBot, "offset must be a constant");
2667 t = base_t->add_offset(offs)->is_oopptr();
2668 }
2669 int inst_id = base_t->instance_id();
2670 assert(!t->is_known_instance() || t->instance_id() == inst_id,
2671 "old type must be non-instance or match new type");
2672
2673 // The type 't' could be subclass of 'base_t'.
2674 // As result t->offset() could be large then base_t's size and it will
2675 // cause the failure in add_offset() with narrow oops since TypeOopPtr()
2676 // constructor verifies correctness of the offset.
2677 //
2678 // It could happened on subclass's branch (from the type profiling
2679 // inlining) which was not eliminated during parsing since the exactness
2680 // of the allocation type was not propagated to the subclass type check.
2681 //
2682 // Or the type 't' could be not related to 'base_t' at all.
2683 // It could happened when CHA type is different from MDO type on a dead path
2684 // (for example, from instanceof check) which is not collapsed during parsing.
2685 //
2686 // Do nothing for such AddP node and don't process its users since
2687 // this code branch will go away.
2688 //
2689 if (!t->is_known_instance() &&
2690 !base_t->maybe_java_subtype_of(t)) {
2691 return false; // bail out
2692 }
2693 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
2694 // Do NOT remove the next line: ensure a new alias index is allocated
2695 // for the instance type. Note: C++ will not remove it since the call
2696 // has side effect.
2697 int alias_idx = _compile->get_alias_index(tinst);
2698 igvn->set_type(addp, tinst);
2699 // record the allocation in the node map
2700 set_map(addp, get_map(base->_idx));
2701 // Set addp's Base and Address to 'base'.
2702 Node *abase = addp->in(AddPNode::Base);
2703 Node *adr = addp->in(AddPNode::Address);
2704 if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
2705 adr->in(0)->_idx == (uint)inst_id) {
2706 // Skip AddP cases #3 and #5.
2707 } else {
2708 assert(!abase->is_top(), "sanity"); // AddP case #3
2709 if (abase != base) {
2710 igvn->hash_delete(addp);
2711 addp->set_req(AddPNode::Base, base);
2712 if (abase == adr) {
2713 addp->set_req(AddPNode::Address, base);
2714 } else {
2715 // AddP case #4 (adr is array's element offset AddP node)
2716 #ifdef ASSERT
2717 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
2718 assert(adr->is_AddP() && atype != NULL &&
2719 atype->instance_id() == inst_id, "array's element offset should be processed first");
2720 #endif
2721 }
2722 igvn->hash_insert(addp);
2723 }
2724 }
2725 // Put on IGVN worklist since at least addp's type was changed above.
2726 record_for_optimizer(addp);
2727 return true;
2728 }
2729
2730 //
2731 // Create a new version of orig_phi if necessary. Returns either the newly
2732 // created phi or an existing phi. Sets create_new to indicate whether a new
2733 // phi was created. Cache the last newly created phi in the node map.
2734 //
2735 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) {
2736 Compile *C = _compile;
2737 PhaseGVN* igvn = _igvn;
2738 new_created = false;
2739 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
2740 // nothing to do if orig_phi is bottom memory or matches alias_idx
2741 if (phi_alias_idx == alias_idx) {
2742 return orig_phi;
2743 }
2744 // Have we recently created a Phi for this alias index?
2745 PhiNode *result = get_map_phi(orig_phi->_idx);
2746 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
2747 return result;
2748 }
2749 // Previous check may fail when the same wide memory Phi was split into Phis
2750 // for different memory slices. Search all Phis for this region.
2751 if (result != NULL) {
2752 Node* region = orig_phi->in(0);
2753 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2754 Node* phi = region->fast_out(i);
2755 if (phi->is_Phi() &&
2756 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
2757 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
2758 return phi->as_Phi();
2759 }
2760 }
2761 }
2762 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) {
2763 if (C->do_escape_analysis() == true && !C->failing()) {
2764 // Retry compilation without escape analysis.
2765 // If this is the first failure, the sentinel string will "stick"
2766 // to the Compile object, and the C2Compiler will see it and retry.
2767 C->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
2768 }
2769 return NULL;
2770 }
2771 orig_phi_worklist.append_if_missing(orig_phi);
2772 const TypePtr *atype = C->get_adr_type(alias_idx);
2773 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
2774 C->copy_node_notes_to(result, orig_phi);
2775 igvn->set_type(result, result->bottom_type());
2776 record_for_optimizer(result);
2777 set_map(orig_phi, result);
2778 new_created = true;
2779 return result;
2780 }
2781
2782 //
2783 // Return a new version of Memory Phi "orig_phi" with the inputs having the
2784 // specified alias index.
2785 //
2786 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) {
2787 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
2788 Compile *C = _compile;
2789 PhaseGVN* igvn = _igvn;
2790 bool new_phi_created;
2791 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created);
2792 if (!new_phi_created) {
2793 return result;
2794 }
2795 GrowableArray<PhiNode *> phi_list;
2796 GrowableArray<uint> cur_input;
2797 PhiNode *phi = orig_phi;
2798 uint idx = 1;
2799 bool finished = false;
2800 while(!finished) {
2801 while (idx < phi->req()) {
2802 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist);
2803 if (mem != NULL && mem->is_Phi()) {
2804 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created);
2805 if (new_phi_created) {
2806 // found an phi for which we created a new split, push current one on worklist and begin
2807 // processing new one
2808 phi_list.push(phi);
2809 cur_input.push(idx);
2810 phi = mem->as_Phi();
2811 result = newphi;
2812 idx = 1;
2813 continue;
2814 } else {
2815 mem = newphi;
2816 }
2817 }
2818 if (C->failing()) {
2819 return NULL;
2820 }
2821 result->set_req(idx++, mem);
2822 }
2823 #ifdef ASSERT
2824 // verify that the new Phi has an input for each input of the original
2825 assert( phi->req() == result->req(), "must have same number of inputs.");
2826 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
2827 #endif
2828 // Check if all new phi's inputs have specified alias index.
2829 // Otherwise use old phi.
2830 for (uint i = 1; i < phi->req(); i++) {
2831 Node* in = result->in(i);
2832 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
2833 }
2834 // we have finished processing a Phi, see if there are any more to do
2835 finished = (phi_list.length() == 0 );
2836 if (!finished) {
2837 phi = phi_list.pop();
2838 idx = cur_input.pop();
2839 PhiNode *prev_result = get_map_phi(phi->_idx);
2840 prev_result->set_req(idx++, result);
2841 result = prev_result;
2842 }
2843 }
2844 return result;
2845 }
2846
2847 //
2848 // The next methods are derived from methods in MemNode.
2849 //
2850 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
2851 Node *mem = mmem;
2852 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
2853 // means an array I have not precisely typed yet. Do not do any
2854 // alias stuff with it any time soon.
2855 if (toop->base() != Type::AnyPtr &&
2856 !(toop->isa_instptr() &&
2857 toop->is_instptr()->instance_klass()->is_java_lang_Object() &&
2858 toop->offset() == Type::OffsetBot)) {
2859 mem = mmem->memory_at(alias_idx);
2860 // Update input if it is progress over what we have now
2861 }
2862 return mem;
2863 }
2864
2865 //
2866 // Move memory users to their memory slices.
2867 //
2868 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) {
2869 Compile* C = _compile;
2870 PhaseGVN* igvn = _igvn;
2871 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
2872 assert(tp != NULL, "ptr type");
2873 int alias_idx = C->get_alias_index(tp);
2874 int general_idx = C->get_general_index(alias_idx);
2875
2876 // Move users first
2877 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2878 Node* use = n->fast_out(i);
2879 if (use->is_MergeMem()) {
2880 MergeMemNode* mmem = use->as_MergeMem();
2881 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
2882 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
2883 continue; // Nothing to do
2884 }
2885 // Replace previous general reference to mem node.
2886 uint orig_uniq = C->unique();
2887 Node* m = find_inst_mem(n, general_idx, orig_phis);
2888 assert(orig_uniq == C->unique(), "no new nodes");
2889 mmem->set_memory_at(general_idx, m);
2890 --imax;
2891 --i;
2892 } else if (use->is_MemBar()) {
2893 assert(!use->is_Initialize(), "initializing stores should not be moved");
2894 if (use->req() > MemBarNode::Precedent &&
2895 use->in(MemBarNode::Precedent) == n) {
2896 // Don't move related membars.
2897 record_for_optimizer(use);
2898 continue;
2899 }
2900 tp = use->as_MemBar()->adr_type()->isa_ptr();
2901 if ((tp != NULL && C->get_alias_index(tp) == alias_idx) ||
2902 alias_idx == general_idx) {
2903 continue; // Nothing to do
2904 }
2905 // Move to general memory slice.
2906 uint orig_uniq = C->unique();
2907 Node* m = find_inst_mem(n, general_idx, orig_phis);
2908 assert(orig_uniq == C->unique(), "no new nodes");
2909 igvn->hash_delete(use);
2910 imax -= use->replace_edge(n, m, igvn);
2911 igvn->hash_insert(use);
2912 record_for_optimizer(use);
2913 --i;
2914 #ifdef ASSERT
2915 } else if (use->is_Mem()) {
2916 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) {
2917 // Don't move related cardmark.
2918 continue;
2919 }
2920 // Memory nodes should have new memory input.
2921 tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
2922 assert(tp != NULL, "ptr type");
2923 int idx = C->get_alias_index(tp);
2924 assert(get_map(use->_idx) != NULL || idx == alias_idx,
2925 "Following memory nodes should have new memory input or be on the same memory slice");
2926 } else if (use->is_Phi()) {
2927 // Phi nodes should be split and moved already.
2928 tp = use->as_Phi()->adr_type()->isa_ptr();
2929 assert(tp != NULL, "ptr type");
2930 int idx = C->get_alias_index(tp);
2931 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
2932 } else {
2933 use->dump();
2934 assert(false, "should not be here");
2935 #endif
2936 }
2937 }
2938 }
2939
2940 //
2941 // Search memory chain of "mem" to find a MemNode whose address
2942 // is the specified alias index.
2943 //
2944 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) {
2945 if (orig_mem == NULL) {
2946 return orig_mem;
2947 }
2948 Compile* C = _compile;
2949 PhaseGVN* igvn = _igvn;
2950 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
2951 bool is_instance = (toop != NULL) && toop->is_known_instance();
2952 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
2953 Node *prev = NULL;
2954 Node *result = orig_mem;
2955 while (prev != result) {
2956 prev = result;
2957 if (result == start_mem) {
2958 break; // hit one of our sentinels
2959 }
2960 if (result->is_Mem()) {
2961 const Type *at = igvn->type(result->in(MemNode::Address));
2962 if (at == Type::TOP) {
2963 break; // Dead
2964 }
2965 assert (at->isa_ptr() != NULL, "pointer type required.");
2966 int idx = C->get_alias_index(at->is_ptr());
2967 if (idx == alias_idx) {
2968 break; // Found
2969 }
2970 if (!is_instance && (at->isa_oopptr() == NULL ||
2971 !at->is_oopptr()->is_known_instance())) {
2972 break; // Do not skip store to general memory slice.
2973 }
2974 result = result->in(MemNode::Memory);
2975 }
2976 if (!is_instance) {
2977 continue; // don't search further for non-instance types
2978 }
2979 // skip over a call which does not affect this memory slice
2980 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
2981 Node *proj_in = result->in(0);
2982 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
2983 break; // hit one of our sentinels
2984 } else if (proj_in->is_Call()) {
2985 // ArrayCopy node processed here as well
2986 CallNode *call = proj_in->as_Call();
2987 if (!call->may_modify(toop, igvn)) {
2988 result = call->in(TypeFunc::Memory);
2989 }
2990 } else if (proj_in->is_Initialize()) {
2991 AllocateNode* alloc = proj_in->as_Initialize()->allocation();
2992 // Stop if this is the initialization for the object instance which
2993 // which contains this memory slice, otherwise skip over it.
2994 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) {
2995 result = proj_in->in(TypeFunc::Memory);
2996 }
2997 } else if (proj_in->is_MemBar()) {
2998 // Check if there is an array copy for a clone
2999 // Step over GC barrier when ReduceInitialCardMarks is disabled
3000 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
3001 Node* control_proj_ac = bs->step_over_gc_barrier(proj_in->in(0));
3002
3003 if (control_proj_ac->is_Proj() && control_proj_ac->in(0)->is_ArrayCopy()) {
3004 // Stop if it is a clone
3005 ArrayCopyNode* ac = control_proj_ac->in(0)->as_ArrayCopy();
3006 if (ac->may_modify(toop, igvn)) {
3007 break;
3008 }
3009 }
3010 result = proj_in->in(TypeFunc::Memory);
3011 }
3012 } else if (result->is_MergeMem()) {
3013 MergeMemNode *mmem = result->as_MergeMem();
3014 result = step_through_mergemem(mmem, alias_idx, toop);
3015 if (result == mmem->base_memory()) {
3016 // Didn't find instance memory, search through general slice recursively.
3017 result = mmem->memory_at(C->get_general_index(alias_idx));
3018 result = find_inst_mem(result, alias_idx, orig_phis);
3019 if (C->failing()) {
3020 return NULL;
3021 }
3022 mmem->set_memory_at(alias_idx, result);
3023 }
3024 } else if (result->is_Phi() &&
3025 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
3026 Node *un = result->as_Phi()->unique_input(igvn);
3027 if (un != NULL) {
3028 orig_phis.append_if_missing(result->as_Phi());
3029 result = un;
3030 } else {
3031 break;
3032 }
3033 } else if (result->is_ClearArray()) {
3034 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) {
3035 // Can not bypass initialization of the instance
3036 // we are looking for.
3037 break;
3038 }
3039 // Otherwise skip it (the call updated 'result' value).
3040 } else if (result->Opcode() == Op_SCMemProj) {
3041 Node* mem = result->in(0);
3042 Node* adr = NULL;
3043 if (mem->is_LoadStore()) {
3044 adr = mem->in(MemNode::Address);
3045 } else {
3046 assert(mem->Opcode() == Op_EncodeISOArray ||
3047 mem->Opcode() == Op_StrCompressedCopy, "sanity");
3048 adr = mem->in(3); // Memory edge corresponds to destination array
3049 }
3050 const Type *at = igvn->type(adr);
3051 if (at != Type::TOP) {
3052 assert(at->isa_ptr() != NULL, "pointer type required.");
3053 int idx = C->get_alias_index(at->is_ptr());
3054 if (idx == alias_idx) {
3055 // Assert in debug mode
3056 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
3057 break; // In product mode return SCMemProj node
3058 }
3059 }
3060 result = mem->in(MemNode::Memory);
3061 } else if (result->Opcode() == Op_StrInflatedCopy) {
3062 Node* adr = result->in(3); // Memory edge corresponds to destination array
3063 const Type *at = igvn->type(adr);
3064 if (at != Type::TOP) {
3065 assert(at->isa_ptr() != NULL, "pointer type required.");
3066 int idx = C->get_alias_index(at->is_ptr());
3067 if (idx == alias_idx) {
3068 // Assert in debug mode
3069 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
3070 break; // In product mode return SCMemProj node
3071 }
3072 }
3073 result = result->in(MemNode::Memory);
3074 }
3075 }
3076 if (result->is_Phi()) {
3077 PhiNode *mphi = result->as_Phi();
3078 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
3079 const TypePtr *t = mphi->adr_type();
3080 if (!is_instance) {
3081 // Push all non-instance Phis on the orig_phis worklist to update inputs
3082 // during Phase 4 if needed.
3083 orig_phis.append_if_missing(mphi);
3084 } else if (C->get_alias_index(t) != alias_idx) {
3085 // Create a new Phi with the specified alias index type.
3086 result = split_memory_phi(mphi, alias_idx, orig_phis);
3087 }
3088 }
3089 // the result is either MemNode, PhiNode, InitializeNode.
3090 return result;
3091 }
3092
3093 //
3094 // Convert the types of non-escaped object to instance types where possible,
3095 // propagate the new type information through the graph, and update memory
3096 // edges and MergeMem inputs to reflect the new type.
3097 //
3098 // We start with allocations (and calls which may be allocations) on alloc_worklist.
3099 // The processing is done in 4 phases:
3100 //
3101 // Phase 1: Process possible allocations from alloc_worklist. Create instance
3102 // types for the CheckCastPP for allocations where possible.
3103 // Propagate the new types through users as follows:
3104 // casts and Phi: push users on alloc_worklist
3105 // AddP: cast Base and Address inputs to the instance type
3106 // push any AddP users on alloc_worklist and push any memnode
3107 // users onto memnode_worklist.
3108 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
3109 // search the Memory chain for a store with the appropriate type
3110 // address type. If a Phi is found, create a new version with
3111 // the appropriate memory slices from each of the Phi inputs.
3112 // For stores, process the users as follows:
3113 // MemNode: push on memnode_worklist
3114 // MergeMem: push on mergemem_worklist
3115 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
3116 // moving the first node encountered of each instance type to the
3117 // the input corresponding to its alias index.
3118 // appropriate memory slice.
3119 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
3120 //
3121 // In the following example, the CheckCastPP nodes are the cast of allocation
3122 // results and the allocation of node 29 is non-escaped and eligible to be an
3123 // instance type.
3124 //
3125 // We start with:
3126 //
3127 // 7 Parm #memory
3128 // 10 ConI "12"
3129 // 19 CheckCastPP "Foo"
3130 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
3131 // 29 CheckCastPP "Foo"
3132 // 30 AddP _ 29 29 10 Foo+12 alias_index=4
3133 //
3134 // 40 StoreP 25 7 20 ... alias_index=4
3135 // 50 StoreP 35 40 30 ... alias_index=4
3136 // 60 StoreP 45 50 20 ... alias_index=4
3137 // 70 LoadP _ 60 30 ... alias_index=4
3138 // 80 Phi 75 50 60 Memory alias_index=4
3139 // 90 LoadP _ 80 30 ... alias_index=4
3140 // 100 LoadP _ 80 20 ... alias_index=4
3141 //
3142 //
3143 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
3144 // and creating a new alias index for node 30. This gives:
3145 //
3146 // 7 Parm #memory
3147 // 10 ConI "12"
3148 // 19 CheckCastPP "Foo"
3149 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
3150 // 29 CheckCastPP "Foo" iid=24
3151 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
3152 //
3153 // 40 StoreP 25 7 20 ... alias_index=4
3154 // 50 StoreP 35 40 30 ... alias_index=6
3155 // 60 StoreP 45 50 20 ... alias_index=4
3156 // 70 LoadP _ 60 30 ... alias_index=6
3157 // 80 Phi 75 50 60 Memory alias_index=4
3158 // 90 LoadP _ 80 30 ... alias_index=6
3159 // 100 LoadP _ 80 20 ... alias_index=4
3160 //
3161 // In phase 2, new memory inputs are computed for the loads and stores,
3162 // And a new version of the phi is created. In phase 4, the inputs to
3163 // node 80 are updated and then the memory nodes are updated with the
3164 // values computed in phase 2. This results in:
3165 //
3166 // 7 Parm #memory
3167 // 10 ConI "12"
3168 // 19 CheckCastPP "Foo"
3169 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
3170 // 29 CheckCastPP "Foo" iid=24
3171 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
3172 //
3173 // 40 StoreP 25 7 20 ... alias_index=4
3174 // 50 StoreP 35 7 30 ... alias_index=6
3175 // 60 StoreP 45 40 20 ... alias_index=4
3176 // 70 LoadP _ 50 30 ... alias_index=6
3177 // 80 Phi 75 40 60 Memory alias_index=4
3178 // 120 Phi 75 50 50 Memory alias_index=6
3179 // 90 LoadP _ 120 30 ... alias_index=6
3180 // 100 LoadP _ 80 20 ... alias_index=4
3181 //
3182 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist,
3183 GrowableArray<ArrayCopyNode*> &arraycopy_worklist,
3184 GrowableArray<MergeMemNode*> &mergemem_worklist) {
3185 GrowableArray<Node *> memnode_worklist;
3186 GrowableArray<PhiNode *> orig_phis;
3187 PhaseIterGVN *igvn = _igvn;
3188 uint new_index_start = (uint) _compile->num_alias_types();
3189 VectorSet visited;
3190 ideal_nodes.clear(); // Reset for use with set_map/get_map.
3191 uint unique_old = _compile->unique();
3192
3193 // Phase 1: Process possible allocations from alloc_worklist.
3194 // Create instance types for the CheckCastPP for allocations where possible.
3195 //
3196 // (Note: don't forget to change the order of the second AddP node on
3197 // the alloc_worklist if the order of the worklist processing is changed,
3198 // see the comment in find_second_addp().)
3199 //
3200 while (alloc_worklist.length() != 0) {
3201 Node *n = alloc_worklist.pop();
3202 uint ni = n->_idx;
3203 if (n->is_Call()) {
3204 CallNode *alloc = n->as_Call();
3205 // copy escape information to call node
3206 PointsToNode* ptn = ptnode_adr(alloc->_idx);
3207 PointsToNode::EscapeState es = ptn->escape_state();
3208 // We have an allocation or call which returns a Java object,
3209 // see if it is non-escaped.
3210 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) {
3211 continue;
3212 }
3213 // Find CheckCastPP for the allocate or for the return value of a call
3214 n = alloc->result_cast();
3215 if (n == NULL) { // No uses except Initialize node
3216 if (alloc->is_Allocate()) {
3217 // Set the scalar_replaceable flag for allocation
3218 // so it could be eliminated if it has no uses.
3219 alloc->as_Allocate()->_is_scalar_replaceable = true;
3220 }
3221 continue;
3222 }
3223 if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
3224 // we could reach here for allocate case if one init is associated with many allocs.
3225 if (alloc->is_Allocate()) {
3226 alloc->as_Allocate()->_is_scalar_replaceable = false;
3227 }
3228 continue;
3229 }
3230
3231 // The inline code for Object.clone() casts the allocation result to
3232 // java.lang.Object and then to the actual type of the allocated
3233 // object. Detect this case and use the second cast.
3234 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
3235 // the allocation result is cast to java.lang.Object and then
3236 // to the actual Array type.
3237 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
3238 && (alloc->is_AllocateArray() ||
3239 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeInstKlassPtr::OBJECT)) {
3240 Node *cast2 = NULL;
3241 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3242 Node *use = n->fast_out(i);
3243 if (use->is_CheckCastPP()) {
3244 cast2 = use;
3245 break;
3246 }
3247 }
3248 if (cast2 != NULL) {
3249 n = cast2;
3250 } else {
3251 // Non-scalar replaceable if the allocation type is unknown statically
3252 // (reflection allocation), the object can't be restored during
3253 // deoptimization without precise type.
3254 continue;
3255 }
3256 }
3257
3258 const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
3259 if (t == NULL) {
3260 continue; // not a TypeOopPtr
3261 }
3262 if (!t->klass_is_exact()) {
3263 continue; // not an unique type
3264 }
3265 if (alloc->is_Allocate()) {
3266 // Set the scalar_replaceable flag for allocation
3267 // so it could be eliminated.
3268 alloc->as_Allocate()->_is_scalar_replaceable = true;
3269 }
3270 set_escape_state(ptnode_adr(n->_idx), es NOT_PRODUCT(COMMA trace_propagate_message(ptn))); // CheckCastPP escape state
3271 // in order for an object to be scalar-replaceable, it must be:
3272 // - a direct allocation (not a call returning an object)
3273 // - non-escaping
3274 // - eligible to be a unique type
3275 // - not determined to be ineligible by escape analysis
3276 set_map(alloc, n);
3277 set_map(n, alloc);
3278 const TypeOopPtr* tinst = t->cast_to_instance_id(ni);
3279 igvn->hash_delete(n);
3280 igvn->set_type(n, tinst);
3281 n->raise_bottom_type(tinst);
3282 igvn->hash_insert(n);
3283 record_for_optimizer(n);
3284 // Allocate an alias index for the header fields. Accesses to
3285 // the header emitted during macro expansion wouldn't have
3286 // correct memory state otherwise.
3287 _compile->get_alias_index(tinst->add_offset(oopDesc::mark_offset_in_bytes()));
3288 _compile->get_alias_index(tinst->add_offset(oopDesc::klass_offset_in_bytes()));
3289 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) {
3290
3291 // First, put on the worklist all Field edges from Connection Graph
3292 // which is more accurate than putting immediate users from Ideal Graph.
3293 for (EdgeIterator e(ptn); e.has_next(); e.next()) {
3294 PointsToNode* tgt = e.get();
3295 if (tgt->is_Arraycopy()) {
3296 continue;
3297 }
3298 Node* use = tgt->ideal_node();
3299 assert(tgt->is_Field() && use->is_AddP(),
3300 "only AddP nodes are Field edges in CG");
3301 if (use->outcnt() > 0) { // Don't process dead nodes
3302 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
3303 if (addp2 != NULL) {
3304 assert(alloc->is_AllocateArray(),"array allocation was expected");
3305 alloc_worklist.append_if_missing(addp2);
3306 }
3307 alloc_worklist.append_if_missing(use);
3308 }
3309 }
3310
3311 // An allocation may have an Initialize which has raw stores. Scan
3312 // the users of the raw allocation result and push AddP users
3313 // on alloc_worklist.
3314 Node *raw_result = alloc->proj_out_or_null(TypeFunc::Parms);
3315 assert (raw_result != NULL, "must have an allocation result");
3316 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
3317 Node *use = raw_result->fast_out(i);
3318 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
3319 Node* addp2 = find_second_addp(use, raw_result);
3320 if (addp2 != NULL) {
3321 assert(alloc->is_AllocateArray(),"array allocation was expected");
3322 alloc_worklist.append_if_missing(addp2);
3323 }
3324 alloc_worklist.append_if_missing(use);
3325 } else if (use->is_MemBar()) {
3326 memnode_worklist.append_if_missing(use);
3327 }
3328 }
3329 }
3330 } else if (n->is_AddP()) {
3331 JavaObjectNode* jobj = unique_java_object(get_addp_base(n));
3332 if (jobj == NULL || jobj == phantom_obj) {
3333 #ifdef ASSERT
3334 ptnode_adr(get_addp_base(n)->_idx)->dump();
3335 ptnode_adr(n->_idx)->dump();
3336 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3337 #endif
3338 _compile->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
3339 return;
3340 }
3341 Node *base = get_map(jobj->idx()); // CheckCastPP node
3342 if (!split_AddP(n, base)) continue; // wrong type from dead path
3343 } else if (n->is_Phi() ||
3344 n->is_CheckCastPP() ||
3345 n->is_EncodeP() ||
3346 n->is_DecodeN() ||
3347 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
3348 if (visited.test_set(n->_idx)) {
3349 assert(n->is_Phi(), "loops only through Phi's");
3350 continue; // already processed
3351 }
3352 JavaObjectNode* jobj = unique_java_object(n);
3353 if (jobj == NULL || jobj == phantom_obj) {
3354 #ifdef ASSERT
3355 ptnode_adr(n->_idx)->dump();
3356 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3357 #endif
3358 _compile->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
3359 return;
3360 } else {
3361 Node *val = get_map(jobj->idx()); // CheckCastPP node
3362 TypeNode *tn = n->as_Type();
3363 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr();
3364 assert(tinst != NULL && tinst->is_known_instance() &&
3365 tinst->instance_id() == jobj->idx() , "instance type expected.");
3366
3367 const Type *tn_type = igvn->type(tn);
3368 const TypeOopPtr *tn_t;
3369 if (tn_type->isa_narrowoop()) {
3370 tn_t = tn_type->make_ptr()->isa_oopptr();
3371 } else {
3372 tn_t = tn_type->isa_oopptr();
3373 }
3374 if (tn_t != NULL && tinst->maybe_java_subtype_of(tn_t)) {
3375 if (tn_type->isa_narrowoop()) {
3376 tn_type = tinst->make_narrowoop();
3377 } else {
3378 tn_type = tinst;
3379 }
3380 igvn->hash_delete(tn);
3381 igvn->set_type(tn, tn_type);
3382 tn->set_type(tn_type);
3383 igvn->hash_insert(tn);
3384 record_for_optimizer(n);
3385 } else {
3386 assert(tn_type == TypePtr::NULL_PTR ||
3387 tn_t != NULL && !tinst->maybe_java_subtype_of(tn_t),
3388 "unexpected type");
3389 continue; // Skip dead path with different type
3390 }
3391 }
3392 } else {
3393 debug_only(n->dump();)
3394 assert(false, "EA: unexpected node");
3395 continue;
3396 }
3397 // push allocation's users on appropriate worklist
3398 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3399 Node *use = n->fast_out(i);
3400 if(use->is_Mem() && use->in(MemNode::Address) == n) {
3401 // Load/store to instance's field
3402 memnode_worklist.append_if_missing(use);
3403 } else if (use->is_MemBar()) {
3404 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3405 memnode_worklist.append_if_missing(use);
3406 }
3407 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
3408 Node* addp2 = find_second_addp(use, n);
3409 if (addp2 != NULL) {
3410 alloc_worklist.append_if_missing(addp2);
3411 }
3412 alloc_worklist.append_if_missing(use);
3413 } else if (use->is_Phi() ||
3414 use->is_CheckCastPP() ||
3415 use->is_EncodeNarrowPtr() ||
3416 use->is_DecodeNarrowPtr() ||
3417 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
3418 alloc_worklist.append_if_missing(use);
3419 #ifdef ASSERT
3420 } else if (use->is_Mem()) {
3421 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
3422 } else if (use->is_MergeMem()) {
3423 assert(mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3424 } else if (use->is_SafePoint()) {
3425 // Look for MergeMem nodes for calls which reference unique allocation
3426 // (through CheckCastPP nodes) even for debug info.
3427 Node* m = use->in(TypeFunc::Memory);
3428 if (m->is_MergeMem()) {
3429 assert(mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3430 }
3431 } else if (use->Opcode() == Op_EncodeISOArray) {
3432 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3433 // EncodeISOArray overwrites destination array
3434 memnode_worklist.append_if_missing(use);
3435 }
3436 } else {
3437 uint op = use->Opcode();
3438 if ((op == Op_StrCompressedCopy || op == Op_StrInflatedCopy) &&
3439 (use->in(MemNode::Memory) == n)) {
3440 // They overwrite memory edge corresponding to destination array,
3441 memnode_worklist.append_if_missing(use);
3442 } else if (!(op == Op_CmpP || op == Op_Conv2B ||
3443 op == Op_CastP2X || op == Op_StoreCM ||
3444 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp ||
3445 op == Op_CountPositives ||
3446 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3447 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar ||
3448 op == Op_SubTypeCheck ||
3449 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use))) {
3450 n->dump();
3451 use->dump();
3452 assert(false, "EA: missing allocation reference path");
3453 }
3454 #endif
3455 }
3456 }
3457
3458 }
3459
3460 // Go over all ArrayCopy nodes and if one of the inputs has a unique
3461 // type, record it in the ArrayCopy node so we know what memory this
3462 // node uses/modified.
3463 for (int next = 0; next < arraycopy_worklist.length(); next++) {
3464 ArrayCopyNode* ac = arraycopy_worklist.at(next);
3465 Node* dest = ac->in(ArrayCopyNode::Dest);
3466 if (dest->is_AddP()) {
3467 dest = get_addp_base(dest);
3468 }
3469 JavaObjectNode* jobj = unique_java_object(dest);
3470 if (jobj != NULL) {
3471 Node *base = get_map(jobj->idx());
3472 if (base != NULL) {
3473 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3474 ac->_dest_type = base_t;
3475 }
3476 }
3477 Node* src = ac->in(ArrayCopyNode::Src);
3478 if (src->is_AddP()) {
3479 src = get_addp_base(src);
3480 }
3481 jobj = unique_java_object(src);
3482 if (jobj != NULL) {
3483 Node* base = get_map(jobj->idx());
3484 if (base != NULL) {
3485 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3486 ac->_src_type = base_t;
3487 }
3488 }
3489 }
3490
3491 // New alias types were created in split_AddP().
3492 uint new_index_end = (uint) _compile->num_alias_types();
3493 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1");
3494
3495 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
3496 // compute new values for Memory inputs (the Memory inputs are not
3497 // actually updated until phase 4.)
3498 if (memnode_worklist.length() == 0)
3499 return; // nothing to do
3500 while (memnode_worklist.length() != 0) {
3501 Node *n = memnode_worklist.pop();
3502 if (visited.test_set(n->_idx)) {
3503 continue;
3504 }
3505 if (n->is_Phi() || n->is_ClearArray()) {
3506 // we don't need to do anything, but the users must be pushed
3507 } else if (n->is_MemBar()) { // Initialize, MemBar nodes
3508 // we don't need to do anything, but the users must be pushed
3509 n = n->as_MemBar()->proj_out_or_null(TypeFunc::Memory);
3510 if (n == NULL) {
3511 continue;
3512 }
3513 } else if (n->Opcode() == Op_StrCompressedCopy ||
3514 n->Opcode() == Op_EncodeISOArray) {
3515 // get the memory projection
3516 n = n->find_out_with(Op_SCMemProj);
3517 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required");
3518 } else {
3519 assert(n->is_Mem(), "memory node required.");
3520 Node *addr = n->in(MemNode::Address);
3521 const Type *addr_t = igvn->type(addr);
3522 if (addr_t == Type::TOP) {
3523 continue;
3524 }
3525 assert (addr_t->isa_ptr() != NULL, "pointer type required.");
3526 int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
3527 assert ((uint)alias_idx < new_index_end, "wrong alias index");
3528 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis);
3529 if (_compile->failing()) {
3530 return;
3531 }
3532 if (mem != n->in(MemNode::Memory)) {
3533 // We delay the memory edge update since we need old one in
3534 // MergeMem code below when instances memory slices are separated.
3535 set_map(n, mem);
3536 }
3537 if (n->is_Load()) {
3538 continue; // don't push users
3539 } else if (n->is_LoadStore()) {
3540 // get the memory projection
3541 n = n->find_out_with(Op_SCMemProj);
3542 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required");
3543 }
3544 }
3545 // push user on appropriate worklist
3546 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3547 Node *use = n->fast_out(i);
3548 if (use->is_Phi() || use->is_ClearArray()) {
3549 memnode_worklist.append_if_missing(use);
3550 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) {
3551 if (use->Opcode() == Op_StoreCM) { // Ignore cardmark stores
3552 continue;
3553 }
3554 memnode_worklist.append_if_missing(use);
3555 } else if (use->is_MemBar()) {
3556 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3557 memnode_worklist.append_if_missing(use);
3558 }
3559 #ifdef ASSERT
3560 } else if(use->is_Mem()) {
3561 assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
3562 } else if (use->is_MergeMem()) {
3563 assert(mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3564 } else if (use->Opcode() == Op_EncodeISOArray) {
3565 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3566 // EncodeISOArray overwrites destination array
3567 memnode_worklist.append_if_missing(use);
3568 }
3569 } else {
3570 uint op = use->Opcode();
3571 if ((use->in(MemNode::Memory) == n) &&
3572 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) {
3573 // They overwrite memory edge corresponding to destination array,
3574 memnode_worklist.append_if_missing(use);
3575 } else if (!(BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use) ||
3576 op == Op_AryEq || op == Op_StrComp || op == Op_CountPositives ||
3577 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3578 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) {
3579 n->dump();
3580 use->dump();
3581 assert(false, "EA: missing memory path");
3582 }
3583 #endif
3584 }
3585 }
3586 }
3587
3588 // Phase 3: Process MergeMem nodes from mergemem_worklist.
3589 // Walk each memory slice moving the first node encountered of each
3590 // instance type to the input corresponding to its alias index.
3591 uint length = mergemem_worklist.length();
3592 for( uint next = 0; next < length; ++next ) {
3593 MergeMemNode* nmm = mergemem_worklist.at(next);
3594 assert(!visited.test_set(nmm->_idx), "should not be visited before");
3595 // Note: we don't want to use MergeMemStream here because we only want to
3596 // scan inputs which exist at the start, not ones we add during processing.
3597 // Note 2: MergeMem may already contains instance memory slices added
3598 // during find_inst_mem() call when memory nodes were processed above.
3599 igvn->hash_delete(nmm);
3600 uint nslices = MIN2(nmm->req(), new_index_start);
3601 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
3602 Node* mem = nmm->in(i);
3603 Node* cur = NULL;
3604 if (mem == NULL || mem->is_top()) {
3605 continue;
3606 }
3607 // First, update mergemem by moving memory nodes to corresponding slices
3608 // if their type became more precise since this mergemem was created.
3609 while (mem->is_Mem()) {
3610 const Type *at = igvn->type(mem->in(MemNode::Address));
3611 if (at != Type::TOP) {
3612 assert (at->isa_ptr() != NULL, "pointer type required.");
3613 uint idx = (uint)_compile->get_alias_index(at->is_ptr());
3614 if (idx == i) {
3615 if (cur == NULL) {
3616 cur = mem;
3617 }
3618 } else {
3619 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
3620 nmm->set_memory_at(idx, mem);
3621 }
3622 }
3623 }
3624 mem = mem->in(MemNode::Memory);
3625 }
3626 nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
3627 // Find any instance of the current type if we haven't encountered
3628 // already a memory slice of the instance along the memory chain.
3629 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3630 if((uint)_compile->get_general_index(ni) == i) {
3631 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
3632 if (nmm->is_empty_memory(m)) {
3633 Node* result = find_inst_mem(mem, ni, orig_phis);
3634 if (_compile->failing()) {
3635 return;
3636 }
3637 nmm->set_memory_at(ni, result);
3638 }
3639 }
3640 }
3641 }
3642 // Find the rest of instances values
3643 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3644 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
3645 Node* result = step_through_mergemem(nmm, ni, tinst);
3646 if (result == nmm->base_memory()) {
3647 // Didn't find instance memory, search through general slice recursively.
3648 result = nmm->memory_at(_compile->get_general_index(ni));
3649 result = find_inst_mem(result, ni, orig_phis);
3650 if (_compile->failing()) {
3651 return;
3652 }
3653 nmm->set_memory_at(ni, result);
3654 }
3655 }
3656 igvn->hash_insert(nmm);
3657 record_for_optimizer(nmm);
3658 }
3659
3660 // Phase 4: Update the inputs of non-instance memory Phis and
3661 // the Memory input of memnodes
3662 // First update the inputs of any non-instance Phi's from
3663 // which we split out an instance Phi. Note we don't have
3664 // to recursively process Phi's encountered on the input memory
3665 // chains as is done in split_memory_phi() since they will
3666 // also be processed here.
3667 for (int j = 0; j < orig_phis.length(); j++) {
3668 PhiNode *phi = orig_phis.at(j);
3669 int alias_idx = _compile->get_alias_index(phi->adr_type());
3670 igvn->hash_delete(phi);
3671 for (uint i = 1; i < phi->req(); i++) {
3672 Node *mem = phi->in(i);
3673 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis);
3674 if (_compile->failing()) {
3675 return;
3676 }
3677 if (mem != new_mem) {
3678 phi->set_req(i, new_mem);
3679 }
3680 }
3681 igvn->hash_insert(phi);
3682 record_for_optimizer(phi);
3683 }
3684
3685 // Update the memory inputs of MemNodes with the value we computed
3686 // in Phase 2 and move stores memory users to corresponding memory slices.
3687 // Disable memory split verification code until the fix for 6984348.
3688 // Currently it produces false negative results since it does not cover all cases.
3689 #if 0 // ifdef ASSERT
3690 visited.Reset();
3691 Node_Stack old_mems(arena, _compile->unique() >> 2);
3692 #endif
3693 for (uint i = 0; i < ideal_nodes.size(); i++) {
3694 Node* n = ideal_nodes.at(i);
3695 Node* nmem = get_map(n->_idx);
3696 assert(nmem != NULL, "sanity");
3697 if (n->is_Mem()) {
3698 #if 0 // ifdef ASSERT
3699 Node* old_mem = n->in(MemNode::Memory);
3700 if (!visited.test_set(old_mem->_idx)) {
3701 old_mems.push(old_mem, old_mem->outcnt());
3702 }
3703 #endif
3704 assert(n->in(MemNode::Memory) != nmem, "sanity");
3705 if (!n->is_Load()) {
3706 // Move memory users of a store first.
3707 move_inst_mem(n, orig_phis);
3708 }
3709 // Now update memory input
3710 igvn->hash_delete(n);
3711 n->set_req(MemNode::Memory, nmem);
3712 igvn->hash_insert(n);
3713 record_for_optimizer(n);
3714 } else {
3715 assert(n->is_Allocate() || n->is_CheckCastPP() ||
3716 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()");
3717 }
3718 }
3719 #if 0 // ifdef ASSERT
3720 // Verify that memory was split correctly
3721 while (old_mems.is_nonempty()) {
3722 Node* old_mem = old_mems.node();
3723 uint old_cnt = old_mems.index();
3724 old_mems.pop();
3725 assert(old_cnt == old_mem->outcnt(), "old mem could be lost");
3726 }
3727 #endif
3728 }
3729
3730 #ifndef PRODUCT
3731 int ConnectionGraph::_no_escape_counter = 0;
3732 int ConnectionGraph::_arg_escape_counter = 0;
3733 int ConnectionGraph::_global_escape_counter = 0;
3734
3735 static const char *node_type_names[] = {
3736 "UnknownType",
3737 "JavaObject",
3738 "LocalVar",
3739 "Field",
3740 "Arraycopy"
3741 };
3742
3743 static const char *esc_names[] = {
3744 "UnknownEscape",
3745 "NoEscape",
3746 "ArgEscape",
3747 "GlobalEscape"
3748 };
3749
3750 void PointsToNode::dump_header(bool print_state, outputStream* out) const {
3751 NodeType nt = node_type();
3752 out->print("%s(%d) ", node_type_names[(int) nt], _pidx);
3753 if (print_state) {
3754 EscapeState es = escape_state();
3755 EscapeState fields_es = fields_escape_state();
3756 out->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]);
3757 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) {
3758 out->print("NSR ");
3759 }
3760 }
3761 }
3762
3763 void PointsToNode::dump(bool print_state, outputStream* out, bool newline) const {
3764 dump_header(print_state, out);
3765 if (is_Field()) {
3766 FieldNode* f = (FieldNode*)this;
3767 if (f->is_oop()) {
3768 out->print("oop ");
3769 }
3770 if (f->offset() > 0) {
3771 out->print("+%d ", f->offset());
3772 }
3773 out->print("(");
3774 for (BaseIterator i(f); i.has_next(); i.next()) {
3775 PointsToNode* b = i.get();
3776 out->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : ""));
3777 }
3778 out->print(" )");
3779 }
3780 out->print("[");
3781 for (EdgeIterator i(this); i.has_next(); i.next()) {
3782 PointsToNode* e = i.get();
3783 out->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : "");
3784 }
3785 out->print(" [");
3786 for (UseIterator i(this); i.has_next(); i.next()) {
3787 PointsToNode* u = i.get();
3788 bool is_base = false;
3789 if (PointsToNode::is_base_use(u)) {
3790 is_base = true;
3791 u = PointsToNode::get_use_node(u)->as_Field();
3792 }
3793 out->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : "");
3794 }
3795 out->print(" ]] ");
3796 if (_node == NULL) {
3797 out->print("<null>%s", newline ? "\n" : "");
3798 } else {
3799 _node->dump(newline ? "\n" : "", false, out);
3800 }
3801 }
3802
3803 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) {
3804 bool first = true;
3805 int ptnodes_length = ptnodes_worklist.length();
3806 for (int i = 0; i < ptnodes_length; i++) {
3807 PointsToNode *ptn = ptnodes_worklist.at(i);
3808 if (ptn == NULL || !ptn->is_JavaObject()) {
3809 continue;
3810 }
3811 PointsToNode::EscapeState es = ptn->escape_state();
3812 if ((es != PointsToNode::NoEscape) && !Verbose) {
3813 continue;
3814 }
3815 Node* n = ptn->ideal_node();
3816 if (n->is_Allocate() || (n->is_CallStaticJava() &&
3817 n->as_CallStaticJava()->is_boxing_method())) {
3818 if (first) {
3819 tty->cr();
3820 tty->print("======== Connection graph for ");
3821 _compile->method()->print_short_name();
3822 tty->cr();
3823 tty->print_cr("invocation #%d: %d iterations and %f sec to build connection graph with %d nodes and worklist size %d",
3824 _invocation, _build_iterations, _build_time, nodes_size(), ptnodes_worklist.length());
3825 tty->cr();
3826 first = false;
3827 }
3828 ptn->dump();
3829 // Print all locals and fields which reference this allocation
3830 for (UseIterator j(ptn); j.has_next(); j.next()) {
3831 PointsToNode* use = j.get();
3832 if (use->is_LocalVar()) {
3833 use->dump(Verbose);
3834 } else if (Verbose) {
3835 use->dump();
3836 }
3837 }
3838 tty->cr();
3839 }
3840 }
3841 }
3842
3843 void ConnectionGraph::print_statistics() {
3844 tty->print_cr("No escape = %d, Arg escape = %d, Global escape = %d", Atomic::load(&_no_escape_counter), Atomic::load(&_arg_escape_counter), Atomic::load(&_global_escape_counter));
3845 }
3846
3847 void ConnectionGraph::escape_state_statistics(GrowableArray<JavaObjectNode*>& java_objects_worklist) {
3848 if (!PrintOptoStatistics || (_invocation > 0)) { // Collect data only for the first invocation
3849 return;
3850 }
3851 for (int next = 0; next < java_objects_worklist.length(); ++next) {
3852 JavaObjectNode* ptn = java_objects_worklist.at(next);
3853 if (ptn->ideal_node()->is_Allocate()) {
3854 if (ptn->escape_state() == PointsToNode::NoEscape) {
3855 Atomic::inc(&ConnectionGraph::_no_escape_counter);
3856 } else if (ptn->escape_state() == PointsToNode::ArgEscape) {
3857 Atomic::inc(&ConnectionGraph::_arg_escape_counter);
3858 } else if (ptn->escape_state() == PointsToNode::GlobalEscape) {
3859 Atomic::inc(&ConnectionGraph::_global_escape_counter);
3860 } else {
3861 assert(false, "Unexpected Escape State");
3862 }
3863 }
3864 }
3865 }
3866
3867 void ConnectionGraph::trace_es_update_helper(PointsToNode* ptn, PointsToNode::EscapeState es, bool fields, const char* reason) const {
3868 if (_compile->directive()->TraceEscapeAnalysisOption) {
3869 assert(ptn != nullptr, "should not be null");
3870 assert(reason != nullptr, "should not be null");
3871 ptn->dump_header(true);
3872 PointsToNode::EscapeState new_es = fields ? ptn->escape_state() : es;
3873 PointsToNode::EscapeState new_fields_es = fields ? es : ptn->fields_escape_state();
3874 tty->print_cr("-> %s(%s) %s", esc_names[(int)new_es], esc_names[(int)new_fields_es], reason);
3875 }
3876 }
3877
3878 const char* ConnectionGraph::trace_propagate_message(PointsToNode* from) const {
3879 if (_compile->directive()->TraceEscapeAnalysisOption) {
3880 stringStream ss;
3881 ss.print("propagated from: ");
3882 from->dump(true, &ss, false);
3883 return ss.as_string();
3884 } else {
3885 return nullptr;
3886 }
3887 }
3888
3889 const char* ConnectionGraph::trace_arg_escape_message(CallNode* call) const {
3890 if (_compile->directive()->TraceEscapeAnalysisOption) {
3891 stringStream ss;
3892 ss.print("escapes as arg to:");
3893 call->dump("", false, &ss);
3894 return ss.as_string();
3895 } else {
3896 return nullptr;
3897 }
3898 }
3899
3900 const char* ConnectionGraph::trace_merged_message(PointsToNode* other) const {
3901 if (_compile->directive()->TraceEscapeAnalysisOption) {
3902 stringStream ss;
3903 ss.print("is merged with other object: ");
3904 other->dump_header(true, &ss);
3905 return ss.as_string();
3906 } else {
3907 return nullptr;
3908 }
3909 }
3910
3911 #endif
3912
3913 void ConnectionGraph::record_for_optimizer(Node *n) {
3914 _igvn->_worklist.push(n);
3915 _igvn->add_users_to_worklist(n);
3916 }