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