1 /*
2 * Copyright (c) 2005, 2023, 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/macro.hpp"
40 #include "opto/phaseX.hpp"
41 #include "opto/movenode.hpp"
42 #include "opto/rootnode.hpp"
43 #include "utilities/macros.hpp"
44
45 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn, int invocation) :
46 // If ReduceAllocationMerges is enabled we might call split_through_phi during
47 // split_unique_types and that will create additional nodes that need to be
48 // pushed to the ConnectionGraph. The code below bumps the initial capacity of
49 // _nodes by 10% to account for these additional nodes. If capacity is exceeded
50 // the array will be reallocated.
51 _nodes(C->comp_arena(), C->do_reduce_allocation_merges() ? C->unique()*1.10 : C->unique(), C->unique(), nullptr),
52 _in_worklist(C->comp_arena()),
53 _next_pidx(0),
54 _collecting(true),
55 _verify(false),
56 _compile(C),
57 _igvn(igvn),
58 _invocation(invocation),
59 _build_iterations(0),
60 _build_time(0.),
61 _node_map(C->comp_arena()) {
62 // Add unknown java object.
63 add_java_object(C->top(), PointsToNode::GlobalEscape);
64 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject();
65 set_not_scalar_replaceable(phantom_obj NOT_PRODUCT(COMMA "Phantom object"));
66 // Add ConP and ConN null oop nodes
67 Node* oop_null = igvn->zerocon(T_OBJECT);
68 assert(oop_null->_idx < nodes_size(), "should be created already");
69 add_java_object(oop_null, PointsToNode::NoEscape);
70 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject();
71 set_not_scalar_replaceable(null_obj NOT_PRODUCT(COMMA "Null object"));
72 if (UseCompressedOops) {
73 Node* noop_null = igvn->zerocon(T_NARROWOOP);
74 assert(noop_null->_idx < nodes_size(), "should be created already");
75 map_ideal_node(noop_null, null_obj);
76 }
77 }
78
79 bool ConnectionGraph::has_candidates(Compile *C) {
80 // EA brings benefits only when the code has allocations and/or locks which
81 // are represented by ideal Macro nodes.
82 int cnt = C->macro_count();
83 for (int i = 0; i < cnt; i++) {
84 Node *n = C->macro_node(i);
85 if (n->is_Allocate()) {
86 return true;
87 }
88 if (n->is_Lock()) {
89 Node* obj = n->as_Lock()->obj_node()->uncast();
90 if (!(obj->is_Parm() || obj->is_Con())) {
91 return true;
92 }
93 }
94 if (n->is_CallStaticJava() &&
95 n->as_CallStaticJava()->is_boxing_method()) {
96 return true;
97 }
98 }
99 return false;
100 }
101
102 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
103 Compile::TracePhase tp("escapeAnalysis", &Phase::timers[Phase::_t_escapeAnalysis]);
104 ResourceMark rm;
105
106 // Add ConP and ConN null oop nodes before ConnectionGraph construction
107 // to create space for them in ConnectionGraph::_nodes[].
108 Node* oop_null = igvn->zerocon(T_OBJECT);
109 Node* noop_null = igvn->zerocon(T_NARROWOOP);
110 int invocation = 0;
111 if (C->congraph() != nullptr) {
112 invocation = C->congraph()->_invocation + 1;
113 }
114 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn, invocation);
115 // Perform escape analysis
116 if (congraph->compute_escape()) {
117 // There are non escaping objects.
118 C->set_congraph(congraph);
119 }
120 // Cleanup.
121 if (oop_null->outcnt() == 0) {
122 igvn->hash_delete(oop_null);
123 }
124 if (noop_null->outcnt() == 0) {
125 igvn->hash_delete(noop_null);
126 }
127 }
128
129 bool ConnectionGraph::compute_escape() {
130 Compile* C = _compile;
131 PhaseGVN* igvn = _igvn;
132
133 // Worklists used by EA.
134 Unique_Node_List delayed_worklist;
135 Unique_Node_List reducible_merges;
136 GrowableArray<Node*> alloc_worklist;
137 GrowableArray<Node*> ptr_cmp_worklist;
138 GrowableArray<MemBarStoreStoreNode*> storestore_worklist;
139 GrowableArray<ArrayCopyNode*> arraycopy_worklist;
140 GrowableArray<PointsToNode*> ptnodes_worklist;
141 GrowableArray<JavaObjectNode*> java_objects_worklist;
142 GrowableArray<JavaObjectNode*> non_escaped_allocs_worklist;
143 GrowableArray<FieldNode*> oop_fields_worklist;
144 GrowableArray<SafePointNode*> sfn_worklist;
145 GrowableArray<MergeMemNode*> mergemem_worklist;
146 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; )
147
148 { Compile::TracePhase tp("connectionGraph", &Phase::timers[Phase::_t_connectionGraph]);
149
150 // 1. Populate Connection Graph (CG) with PointsTo nodes.
151 ideal_nodes.map(C->live_nodes(), nullptr); // preallocate space
152 // Initialize worklist
153 if (C->root() != nullptr) {
154 ideal_nodes.push(C->root());
155 }
156 // Processed ideal nodes are unique on ideal_nodes list
157 // but several ideal nodes are mapped to the phantom_obj.
158 // To avoid duplicated entries on the following worklists
159 // add the phantom_obj only once to them.
160 ptnodes_worklist.append(phantom_obj);
161 java_objects_worklist.append(phantom_obj);
162 for( uint next = 0; next < ideal_nodes.size(); ++next ) {
163 Node* n = ideal_nodes.at(next);
164 // Create PointsTo nodes and add them to Connection Graph. Called
165 // only once per ideal node since ideal_nodes is Unique_Node list.
166 add_node_to_connection_graph(n, &delayed_worklist);
167 PointsToNode* ptn = ptnode_adr(n->_idx);
168 if (ptn != nullptr && ptn != phantom_obj) {
169 ptnodes_worklist.append(ptn);
170 if (ptn->is_JavaObject()) {
171 java_objects_worklist.append(ptn->as_JavaObject());
172 if ((n->is_Allocate() || n->is_CallStaticJava()) &&
173 (ptn->escape_state() < PointsToNode::GlobalEscape)) {
174 // Only allocations and java static calls results are interesting.
175 non_escaped_allocs_worklist.append(ptn->as_JavaObject());
176 }
177 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) {
178 oop_fields_worklist.append(ptn->as_Field());
179 }
180 }
181 // Collect some interesting nodes for further use.
182 switch (n->Opcode()) {
183 case Op_MergeMem:
184 // Collect all MergeMem nodes to add memory slices for
185 // scalar replaceable objects in split_unique_types().
186 mergemem_worklist.append(n->as_MergeMem());
187 break;
188 case Op_CmpP:
189 case Op_CmpN:
190 // Collect compare pointers nodes.
191 if (OptimizePtrCompare) {
192 ptr_cmp_worklist.append(n);
193 }
194 break;
195 case Op_MemBarStoreStore:
196 // Collect all MemBarStoreStore nodes so that depending on the
197 // escape status of the associated Allocate node some of them
198 // may be eliminated.
199 storestore_worklist.append(n->as_MemBarStoreStore());
200 break;
201 case Op_MemBarRelease:
202 if (n->req() > MemBarNode::Precedent) {
203 record_for_optimizer(n);
204 }
205 break;
206 #ifdef ASSERT
207 case Op_AddP:
208 // Collect address nodes for graph verification.
209 addp_worklist.append(n);
210 break;
211 #endif
212 case Op_ArrayCopy:
213 // Keep a list of ArrayCopy nodes so if one of its input is non
214 // escaping, we can record a unique type
215 arraycopy_worklist.append(n->as_ArrayCopy());
216 break;
217 default:
218 // not interested now, ignore...
219 break;
220 }
221 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
222 Node* m = n->fast_out(i); // Get user
223 ideal_nodes.push(m);
224 }
225 if (n->is_SafePoint()) {
226 sfn_worklist.append(n->as_SafePoint());
227 }
228 }
229
230 #ifndef PRODUCT
231 if (_compile->directive()->TraceEscapeAnalysisOption) {
232 tty->print("+++++ Initial worklist for ");
233 _compile->method()->print_name();
234 tty->print_cr(" (ea_inv=%d)", _invocation);
235 for (int i = 0; i < ptnodes_worklist.length(); i++) {
236 PointsToNode* ptn = ptnodes_worklist.at(i);
237 ptn->dump();
238 }
239 tty->print_cr("+++++ Calculating escape states and scalar replaceability");
240 }
241 #endif
242
243 if (non_escaped_allocs_worklist.length() == 0) {
244 _collecting = false;
245 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
246 return false; // Nothing to do.
247 }
248 // Add final simple edges to graph.
249 while(delayed_worklist.size() > 0) {
250 Node* n = delayed_worklist.pop();
251 add_final_edges(n);
252 }
253
254 #ifdef ASSERT
255 if (VerifyConnectionGraph) {
256 // Verify that no new simple edges could be created and all
257 // local vars has edges.
258 _verify = true;
259 int ptnodes_length = ptnodes_worklist.length();
260 for (int next = 0; next < ptnodes_length; ++next) {
261 PointsToNode* ptn = ptnodes_worklist.at(next);
262 add_final_edges(ptn->ideal_node());
263 if (ptn->is_LocalVar() && ptn->edge_count() == 0) {
264 ptn->dump();
265 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity");
266 }
267 }
268 _verify = false;
269 }
270 #endif
271 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes
272 // processing, calls to CI to resolve symbols (types, fields, methods)
273 // referenced in bytecode. During symbol resolution VM may throw
274 // an exception which CI cleans and converts to compilation failure.
275 if (C->failing()) {
276 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
277 return false;
278 }
279
280 // 2. Finish Graph construction by propagating references to all
281 // java objects through graph.
282 if (!complete_connection_graph(ptnodes_worklist, non_escaped_allocs_worklist,
283 java_objects_worklist, oop_fields_worklist)) {
284 // All objects escaped or hit time or iterations limits.
285 _collecting = false;
286 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
287 return false;
288 }
289
290 // 3. Adjust scalar_replaceable state of nonescaping objects and push
291 // scalar replaceable allocations on alloc_worklist for processing
292 // in split_unique_types().
293 GrowableArray<JavaObjectNode*> jobj_worklist;
294 int non_escaped_length = non_escaped_allocs_worklist.length();
295 bool found_nsr_alloc = false;
296 for (int next = 0; next < non_escaped_length; next++) {
297 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
298 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape);
299 Node* n = ptn->ideal_node();
300 if (n->is_Allocate()) {
301 n->as_Allocate()->_is_non_escaping = noescape;
302 }
303 if (noescape && ptn->scalar_replaceable()) {
304 adjust_scalar_replaceable_state(ptn, reducible_merges);
305 if (ptn->scalar_replaceable()) {
306 jobj_worklist.push(ptn);
307 } else {
308 found_nsr_alloc = true;
309 }
310 }
311 }
312
313 // Propagate NSR (Not Scalar Replaceable) state.
314 if (found_nsr_alloc) {
315 find_scalar_replaceable_allocs(jobj_worklist);
316 }
317
318 // alloc_worklist will be processed in reverse push order.
319 // Therefore the reducible Phis will be processed for last and that's what we
320 // want because by then the scalarizable inputs of the merge will already have
321 // an unique instance type.
322 for (uint i = 0; i < reducible_merges.size(); i++ ) {
323 Node* n = reducible_merges.at(i);
324 alloc_worklist.append(n);
325 }
326
327 for (int next = 0; next < jobj_worklist.length(); ++next) {
328 JavaObjectNode* jobj = jobj_worklist.at(next);
329 if (jobj->scalar_replaceable()) {
330 alloc_worklist.append(jobj->ideal_node());
331 }
332 }
333
334 #ifdef ASSERT
335 if (VerifyConnectionGraph) {
336 // Verify that graph is complete - no new edges could be added or needed.
337 verify_connection_graph(ptnodes_worklist, non_escaped_allocs_worklist,
338 java_objects_worklist, addp_worklist);
339 }
340 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build");
341 assert(null_obj->escape_state() == PointsToNode::NoEscape &&
342 null_obj->edge_count() == 0 &&
343 !null_obj->arraycopy_src() &&
344 !null_obj->arraycopy_dst(), "sanity");
345 #endif
346
347 _collecting = false;
348
349 } // TracePhase t3("connectionGraph")
350
351 // 4. Optimize ideal graph based on EA information.
352 bool has_non_escaping_obj = (non_escaped_allocs_worklist.length() > 0);
353 if (has_non_escaping_obj) {
354 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist);
355 }
356
357 #ifndef PRODUCT
358 if (PrintEscapeAnalysis) {
359 dump(ptnodes_worklist); // Dump ConnectionGraph
360 }
361 #endif
362
363 #ifdef ASSERT
364 if (VerifyConnectionGraph) {
365 int alloc_length = alloc_worklist.length();
366 for (int next = 0; next < alloc_length; ++next) {
367 Node* n = alloc_worklist.at(next);
368 PointsToNode* ptn = ptnode_adr(n->_idx);
369 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity");
370 }
371 }
372
373 if (VerifyReduceAllocationMerges) {
374 for (uint i = 0; i < reducible_merges.size(); i++ ) {
375 Node* n = reducible_merges.at(i);
376 if (!can_reduce_phi(n->as_Phi())) {
377 TraceReduceAllocationMerges = true;
378 n->dump(2);
379 n->dump(-2);
380 assert(can_reduce_phi(n->as_Phi()), "Sanity: previous reducible Phi is no longer reducible before SUT.");
381 }
382 }
383 }
384 #endif
385
386 // 5. Separate memory graph for scalar replaceable allcations.
387 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0);
388 if (has_scalar_replaceable_candidates && EliminateAllocations) {
389 assert(C->do_aliasing(), "Aliasing should be enabled");
390 // Now use the escape information to create unique types for
391 // scalar replaceable objects.
392 split_unique_types(alloc_worklist, arraycopy_worklist, mergemem_worklist, reducible_merges);
393 if (C->failing()) {
394 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
395 return false;
396 }
397 C->print_method(PHASE_AFTER_EA, 2);
398
399 #ifdef ASSERT
400 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
401 tty->print("=== No allocations eliminated for ");
402 C->method()->print_short_name();
403 if (!EliminateAllocations) {
404 tty->print(" since EliminateAllocations is off ===");
405 } else if(!has_scalar_replaceable_candidates) {
406 tty->print(" since there are no scalar replaceable candidates ===");
407 }
408 tty->cr();
409 #endif
410 }
411
412 // 6. Remove reducible allocation merges from ideal graph
413 if (reducible_merges.size() > 0) {
414 bool delay = _igvn->delay_transform();
415 _igvn->set_delay_transform(true);
416 for (uint i = 0; i < reducible_merges.size(); i++ ) {
417 Node* n = reducible_merges.at(i);
418 reduce_phi(n->as_Phi());
419 if (C->failing()) {
420 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
421 return false;
422 }
423 }
424 _igvn->set_delay_transform(delay);
425 }
426
427 // Annotate at safepoints if they have <= ArgEscape objects in their scope and at
428 // java calls if they pass ArgEscape objects as parameters.
429 if (has_non_escaping_obj &&
430 (C->env()->should_retain_local_variables() ||
431 C->env()->jvmti_can_get_owned_monitor_info() ||
432 C->env()->jvmti_can_walk_any_space() ||
433 DeoptimizeObjectsALot)) {
434 int sfn_length = sfn_worklist.length();
435 for (int next = 0; next < sfn_length; next++) {
436 SafePointNode* sfn = sfn_worklist.at(next);
437 sfn->set_has_ea_local_in_scope(has_ea_local_in_scope(sfn));
438 if (sfn->is_CallJava()) {
439 CallJavaNode* call = sfn->as_CallJava();
440 call->set_arg_escape(has_arg_escape(call));
441 }
442 }
443 }
444
445 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
446 return has_non_escaping_obj;
447 }
448
449 // Check if it's profitable to reduce the Phi passed as parameter. Returns true
450 // if at least one scalar replaceable allocation participates in the merge and
451 // no input to the Phi is nullable.
452 bool ConnectionGraph::can_reduce_phi_check_inputs(PhiNode* ophi) const {
453 // Check if there is a scalar replaceable allocate in the Phi
454 bool found_sr_allocate = false;
455
456 for (uint i = 1; i < ophi->req(); i++) {
457 // Right now we can't restore a "null" pointer during deoptimization
458 const Type* inp_t = _igvn->type(ophi->in(i));
459 if (inp_t == nullptr || inp_t->make_oopptr() == nullptr || inp_t->make_oopptr()->maybe_null()) {
460 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. Input %d is nullable.", ophi->_idx, _invocation, i);)
461 return false;
462 }
463
464 // We are looking for at least one SR object in the merge
465 JavaObjectNode* ptn = unique_java_object(ophi->in(i));
466 if (ptn != nullptr && ptn->scalar_replaceable()) {
467 assert(ptn->ideal_node() != nullptr && ptn->ideal_node()->is_Allocate(), "sanity");
468 AllocateNode* alloc = ptn->ideal_node()->as_Allocate();
469
470 if (PhaseMacroExpand::can_eliminate_allocation(_igvn, alloc, nullptr)) {
471 found_sr_allocate = true;
472 } else {
473 ptn->set_scalar_replaceable(false);
474 }
475 }
476 }
477
478 NOT_PRODUCT(if (TraceReduceAllocationMerges && !found_sr_allocate) tty->print_cr("Can NOT reduce Phi %d on invocation %d. No SR Allocate as input.", ophi->_idx, _invocation);)
479 return found_sr_allocate;
480 }
481
482 // Check if we are able to untangle the merge. Right now we only reduce Phis
483 // which are only used as debug information.
484 bool ConnectionGraph::can_reduce_phi_check_users(PhiNode* ophi) const {
485 for (DUIterator_Fast imax, i = ophi->fast_outs(imax); i < imax; i++) {
486 Node* use = ophi->fast_out(i);
487
488 if (use->is_SafePoint()) {
489 if (use->is_Call() && use->as_Call()->has_non_debug_use(ophi)) {
490 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. Call has non_debug_use().", ophi->_idx, _invocation);)
491 return false;
492 }
493 } else if (use->is_AddP()) {
494 Node* addp = use;
495 for (DUIterator_Fast jmax, j = addp->fast_outs(jmax); j < jmax; j++) {
496 Node* use_use = addp->fast_out(j);
497 if (!use_use->is_Load() || !use_use->as_Load()->can_split_through_phi_base(_igvn)) {
498 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. AddP user isn't a [splittable] Load(): %s", ophi->_idx, _invocation, use_use->Name());)
499 return false;
500 }
501 }
502 } else {
503 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. One of the uses is: %d %s", ophi->_idx, _invocation, use->_idx, use->Name());)
504 return false;
505 }
506 }
507
508 return true;
509 }
510
511 // Returns true if: 1) It's profitable to reduce the merge, and 2) The Phi is
512 // only used in some certain code shapes. Check comments in
513 // 'can_reduce_phi_inputs' and 'can_reduce_phi_users' for more
514 // details.
515 bool ConnectionGraph::can_reduce_phi(PhiNode* ophi) const {
516 // If there was an error attempting to reduce allocation merges for this
517 // method we might have disabled the compilation and be retrying with RAM
518 // disabled.
519 // If EliminateAllocations is False, there is no point in reducing merges.
520 if (!_compile->do_reduce_allocation_merges()) {
521 return false;
522 }
523
524 const Type* phi_t = _igvn->type(ophi);
525 if (phi_t == nullptr || phi_t->make_ptr() == nullptr ||
526 phi_t->make_ptr()->isa_instptr() == nullptr ||
527 !phi_t->make_ptr()->isa_instptr()->klass_is_exact()) {
528 NOT_PRODUCT(if (TraceReduceAllocationMerges) { tty->print_cr("Can NOT reduce Phi %d during invocation %d because it's nullable.", ophi->_idx, _invocation); })
529 return false;
530 }
531
532 if (!can_reduce_phi_check_inputs(ophi) || !can_reduce_phi_check_users(ophi)) {
533 return false;
534 }
535
536 NOT_PRODUCT(if (TraceReduceAllocationMerges) { tty->print_cr("Can reduce Phi %d during invocation %d: ", ophi->_idx, _invocation); })
537 return true;
538 }
539
540 void ConnectionGraph::reduce_phi_on_field_access(PhiNode* ophi, GrowableArray<Node *> &alloc_worklist) {
541 // We'll pass this to 'split_through_phi' so that it'll do the split even
542 // though the load doesn't have an unique instance type.
543 bool ignore_missing_instance_id = true;
544
545 #ifdef ASSERT
546 if (VerifyReduceAllocationMerges && !can_reduce_phi(ophi)) {
547 TraceReduceAllocationMerges = true;
548 ophi->dump(2);
549 ophi->dump(-2);
550 assert(can_reduce_phi(ophi), "Sanity: previous reducible Phi is no longer reducible inside reduce_phi_on_field_access.");
551 }
552 #endif
553
554 // Iterate over Phi outputs looking for an AddP
555 for (int j = ophi->outcnt()-1; j >= 0;) {
556 Node* previous_addp = ophi->raw_out(j);
557 if (previous_addp->is_AddP()) {
558 // All AddPs are present in the connection graph
559 FieldNode* fn = ptnode_adr(previous_addp->_idx)->as_Field();
560
561 // Iterate over AddP looking for a Load
562 for (int k = previous_addp->outcnt()-1; k >= 0;) {
563 Node* previous_load = previous_addp->raw_out(k);
564 if (previous_load->is_Load()) {
565 Node* data_phi = previous_load->as_Load()->split_through_phi(_igvn, ignore_missing_instance_id);
566 _igvn->replace_node(previous_load, data_phi);
567 assert(data_phi != nullptr, "Output of split_through_phi is null.");
568 assert(data_phi != previous_load, "Output of split_through_phi is same as input.");
569 assert(data_phi->is_Phi(), "Return of split_through_phi should be a Phi.");
570
571 // Push the newly created AddP on alloc_worklist and patch
572 // the connection graph. Note that the changes in the CG below
573 // won't affect the ES of objects since the new nodes have the
574 // same status as the old ones.
575 for (uint i = 1; i < data_phi->req(); i++) {
576 Node* new_load = data_phi->in(i);
577 if (new_load->is_Load()) {
578 Node* new_addp = new_load->in(MemNode::Address);
579 Node* base = get_addp_base(new_addp);
580
581 // The base might not be something that we can create an unique
582 // type for. If that's the case we are done with that input.
583 PointsToNode* jobj_ptn = unique_java_object(base);
584 if (jobj_ptn == nullptr || !jobj_ptn->scalar_replaceable()) {
585 continue;
586 }
587
588 // Push to alloc_worklist since the base has an unique_type
589 alloc_worklist.append_if_missing(new_addp);
590
591 // Now let's add the node to the connection graph
592 _nodes.at_grow(new_addp->_idx, nullptr);
593 add_field(new_addp, fn->escape_state(), fn->offset());
594 add_base(ptnode_adr(new_addp->_idx)->as_Field(), ptnode_adr(base->_idx));
595
596 // If the load doesn't load an object then it won't be
597 // part of the connection graph
598 PointsToNode* curr_load_ptn = ptnode_adr(previous_load->_idx);
599 if (curr_load_ptn != nullptr) {
600 _nodes.at_grow(new_load->_idx, nullptr);
601 add_local_var(new_load, curr_load_ptn->escape_state());
602 add_edge(ptnode_adr(new_load->_idx), ptnode_adr(new_addp->_idx)->as_Field());
603 }
604 }
605 }
606 }
607 k = MIN2(--k, (int)previous_addp->outcnt()-1);
608 }
609
610 // Remove the old AddP from the processing list because it's dead now
611 alloc_worklist.remove_if_existing(previous_addp);
612 _igvn->remove_globally_dead_node(previous_addp);
613 }
614 j = MIN2(--j, (int)ophi->outcnt()-1);
615 }
616
617 #ifdef ASSERT
618 if (VerifyReduceAllocationMerges) {
619 for (uint j = 0; j < ophi->outcnt(); j++) {
620 Node* use = ophi->raw_out(j);
621 if (!use->is_SafePoint()) {
622 ophi->dump(2);
623 ophi->dump(-2);
624 assert(false, "Should be a SafePoint.");
625 }
626 }
627 }
628 #endif
629 }
630
631 // This method will create a SafePointScalarObjectNode for each combination of
632 // scalar replaceable allocation in 'ophi' and SafePoint node in 'safepoints'.
633 // The method will create a SafePointScalarMERGEnode for each combination of
634 // 'ophi' and SafePoint node in 'safepoints'.
635 // Each SafePointScalarMergeNode created here may describe multiple scalar
636 // replaced objects - check detailed description in SafePointScalarMergeNode
637 // class header.
638 //
639 // This method will set entries in the Phi that are scalar replaceable to 'null'.
640 void ConnectionGraph::reduce_phi_on_safepoints(PhiNode* ophi, Unique_Node_List* safepoints) {
641 Node* minus_one = _igvn->register_new_node_with_optimizer(ConINode::make(-1));
642 Node* selector = _igvn->register_new_node_with_optimizer(PhiNode::make(ophi->region(), minus_one, TypeInt::INT));
643 Node* null_ptr = _igvn->makecon(TypePtr::NULL_PTR);
644 const TypeOopPtr* merge_t = _igvn->type(ophi)->make_oopptr();
645 uint number_of_sr_objects = 0;
646 PhaseMacroExpand mexp(*_igvn);
647
648 _igvn->hash_delete(ophi);
649
650 // Fill in the 'selector' Phi. If index 'i' of the selector is:
651 // -> a '-1' constant, the i'th input of the original Phi is NSR.
652 // -> a 'x' constant >=0, the i'th input of of original Phi will be SR and the
653 // info about the scalarized object will be at index x of
654 // ObjectMergeValue::possible_objects
655 for (uint i = 1; i < ophi->req(); i++) {
656 Node* base = ophi->in(i);
657 JavaObjectNode* ptn = unique_java_object(base);
658
659 if (ptn != nullptr && ptn->scalar_replaceable()) {
660 Node* sr_obj_idx = _igvn->register_new_node_with_optimizer(ConINode::make(number_of_sr_objects));
661 selector->set_req(i, sr_obj_idx);
662 number_of_sr_objects++;
663 }
664 }
665
666 // Update the debug information of all safepoints in turn
667 for (uint spi = 0; spi < safepoints->size(); spi++) {
668 SafePointNode* sfpt = safepoints->at(spi)->as_SafePoint();
669 JVMState *jvms = sfpt->jvms();
670 uint merge_idx = (sfpt->req() - jvms->scloff());
671 int debug_start = jvms->debug_start();
672
673 SafePointScalarMergeNode* smerge = new SafePointScalarMergeNode(merge_t, merge_idx);
674 smerge->init_req(0, _compile->root());
675 _igvn->register_new_node_with_optimizer(smerge);
676
677 // The next two inputs are:
678 // (1) A copy of the original pointer to NSR objects.
679 // (2) A selector, used to decide if we need to rematerialize an object
680 // or use the pointer to a NSR object.
681 // See more details of these fields in the declaration of SafePointScalarMergeNode
682 sfpt->add_req(ophi);
683 sfpt->add_req(selector);
684
685 for (uint i = 1; i < ophi->req(); i++) {
686 Node* base = ophi->in(i);
687 JavaObjectNode* ptn = unique_java_object(base);
688
689 // If the base is not scalar replaceable we don't need to register information about
690 // it at this time.
691 if (ptn == nullptr || !ptn->scalar_replaceable()) {
692 continue;
693 }
694
695 AllocateNode* alloc = ptn->ideal_node()->as_Allocate();
696 SafePointScalarObjectNode* sobj = mexp.create_scalarized_object_description(alloc, sfpt);
697 if (sobj == nullptr) {
698 _compile->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
699 return;
700 }
701
702 // Now make a pass over the debug information replacing any references
703 // to the allocated object with "sobj"
704 Node* ccpp = alloc->result_cast();
705 sfpt->replace_edges_in_range(ccpp, sobj, debug_start, jvms->debug_end(), _igvn);
706
707 // Register the scalarized object as a candidate for reallocation
708 smerge->add_req(sobj);
709 }
710
711 // Replaces debug information references to "ophi" in "sfpt" with references to "smerge"
712 sfpt->replace_edges_in_range(ophi, smerge, debug_start, jvms->debug_end(), _igvn);
713
714 // The call to 'replace_edges_in_range' above might have removed the
715 // reference to ophi that we need at _merge_pointer_idx. The line below make
716 // sure the reference is maintained.
717 sfpt->set_req(smerge->merge_pointer_idx(jvms), ophi);
718 _igvn->_worklist.push(sfpt);
719 }
720
721 // Now we can change ophi since we don't need to know the types
722 // of the input allocations anymore.
723 const Type* new_t = merge_t->meet(TypePtr::NULL_PTR);
724 Node* new_phi = _igvn->register_new_node_with_optimizer(PhiNode::make(ophi->region(), null_ptr, new_t));
725 for (uint i = 1; i < ophi->req(); i++) {
726 Node* base = ophi->in(i);
727 JavaObjectNode* ptn = unique_java_object(base);
728
729 if (ptn != nullptr && ptn->scalar_replaceable()) {
730 new_phi->set_req(i, null_ptr);
731 } else {
732 new_phi->set_req(i, ophi->in(i));
733 }
734 }
735
736 _igvn->replace_node(ophi, new_phi);
737 _igvn->hash_insert(ophi);
738 _igvn->_worklist.push(ophi);
739 }
740
741 void ConnectionGraph::reduce_phi(PhiNode* ophi) {
742 Unique_Node_List safepoints;
743
744 for (uint i = 0; i < ophi->outcnt(); i++) {
745 Node* use = ophi->raw_out(i);
746
747 // All SafePoint nodes using the same Phi node use the same debug
748 // information (regarding the Phi). Furthermore, reducing the Phi used by a
749 // SafePoint requires changing the Phi. Therefore, I collect all safepoints
750 // and patch them all at once later.
751 if (use->is_SafePoint()) {
752 safepoints.push(use->as_SafePoint());
753 } else {
754 #ifdef ASSERT
755 ophi->dump(-3);
756 assert(false, "Unexpected user of reducible Phi %d -> %d:%s", ophi->_idx, use->_idx, use->Name());
757 #endif
758 _compile->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
759 return;
760 }
761 }
762
763 if (safepoints.size() > 0) {
764 reduce_phi_on_safepoints(ophi, &safepoints);
765 }
766 }
767
768 void ConnectionGraph::verify_ram_nodes(Compile* C, Node* root) {
769 if (!C->do_reduce_allocation_merges()) return;
770
771 Unique_Node_List ideal_nodes;
772 ideal_nodes.map(C->live_nodes(), nullptr); // preallocate space
773 ideal_nodes.push(root);
774
775 for (uint next = 0; next < ideal_nodes.size(); ++next) {
776 Node* n = ideal_nodes.at(next);
777
778 if (n->is_SafePointScalarMerge()) {
779 SafePointScalarMergeNode* merge = n->as_SafePointScalarMerge();
780
781 // Validate inputs of merge
782 for (uint i = 1; i < merge->req(); i++) {
783 if (merge->in(i) != nullptr && !merge->in(i)->is_top() && !merge->in(i)->is_SafePointScalarObject()) {
784 assert(false, "SafePointScalarMerge inputs should be null/top or SafePointScalarObject.");
785 C->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
786 }
787 }
788
789 // Validate users of merge
790 for (DUIterator_Fast imax, i = merge->fast_outs(imax); i < imax; i++) {
791 Node* sfpt = merge->fast_out(i);
792 if (sfpt->is_SafePoint()) {
793 int merge_idx = merge->merge_pointer_idx(sfpt->as_SafePoint()->jvms());
794
795 if (sfpt->in(merge_idx) != nullptr && sfpt->in(merge_idx)->is_SafePointScalarMerge()) {
796 assert(false, "SafePointScalarMerge nodes can't be nested.");
797 C->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
798 }
799 } else {
800 assert(false, "Only safepoints can use SafePointScalarMerge nodes.");
801 C->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
802 }
803 }
804 }
805
806 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
807 Node* m = n->fast_out(i);
808 ideal_nodes.push(m);
809 }
810 }
811 }
812
813 // Returns true if there is an object in the scope of sfn that does not escape globally.
814 bool ConnectionGraph::has_ea_local_in_scope(SafePointNode* sfn) {
815 Compile* C = _compile;
816 for (JVMState* jvms = sfn->jvms(); jvms != nullptr; jvms = jvms->caller()) {
817 if (C->env()->should_retain_local_variables() || C->env()->jvmti_can_walk_any_space() ||
818 DeoptimizeObjectsALot) {
819 // Jvmti agents can access locals. Must provide info about local objects at runtime.
820 int num_locs = jvms->loc_size();
821 for (int idx = 0; idx < num_locs; idx++) {
822 Node* l = sfn->local(jvms, idx);
823 if (not_global_escape(l)) {
824 return true;
825 }
826 }
827 }
828 if (C->env()->jvmti_can_get_owned_monitor_info() ||
829 C->env()->jvmti_can_walk_any_space() || DeoptimizeObjectsALot) {
830 // Jvmti agents can read monitors. Must provide info about locked objects at runtime.
831 int num_mon = jvms->nof_monitors();
832 for (int idx = 0; idx < num_mon; idx++) {
833 Node* m = sfn->monitor_obj(jvms, idx);
834 if (m != nullptr && not_global_escape(m)) {
835 return true;
836 }
837 }
838 }
839 }
840 return false;
841 }
842
843 // Returns true if at least one of the arguments to the call is an object
844 // that does not escape globally.
845 bool ConnectionGraph::has_arg_escape(CallJavaNode* call) {
846 if (call->method() != nullptr) {
847 uint max_idx = TypeFunc::Parms + call->method()->arg_size();
848 for (uint idx = TypeFunc::Parms; idx < max_idx; idx++) {
849 Node* p = call->in(idx);
850 if (not_global_escape(p)) {
851 return true;
852 }
853 }
854 } else {
855 const char* name = call->as_CallStaticJava()->_name;
856 assert(name != nullptr, "no name");
857 // no arg escapes through uncommon traps
858 if (strcmp(name, "uncommon_trap") != 0) {
859 // process_call_arguments() assumes that all arguments escape globally
860 const TypeTuple* d = call->tf()->domain();
861 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
862 const Type* at = d->field_at(i);
863 if (at->isa_oopptr() != nullptr) {
864 return true;
865 }
866 }
867 }
868 }
869 return false;
870 }
871
872
873
874 // Utility function for nodes that load an object
875 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
876 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
877 // ThreadLocal has RawPtr type.
878 const Type* t = _igvn->type(n);
879 if (t->make_ptr() != nullptr) {
880 Node* adr = n->in(MemNode::Address);
881 #ifdef ASSERT
882 if (!adr->is_AddP()) {
883 assert(_igvn->type(adr)->isa_rawptr(), "sanity");
884 } else {
885 assert((ptnode_adr(adr->_idx) == nullptr ||
886 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity");
887 }
888 #endif
889 add_local_var_and_edge(n, PointsToNode::NoEscape,
890 adr, delayed_worklist);
891 }
892 }
893
894 // Populate Connection Graph with PointsTo nodes and create simple
895 // connection graph edges.
896 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
897 assert(!_verify, "this method should not be called for verification");
898 PhaseGVN* igvn = _igvn;
899 uint n_idx = n->_idx;
900 PointsToNode* n_ptn = ptnode_adr(n_idx);
901 if (n_ptn != nullptr) {
902 return; // No need to redefine PointsTo node during first iteration.
903 }
904 int opcode = n->Opcode();
905 bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_to_con_graph(this, igvn, delayed_worklist, n, opcode);
906 if (gc_handled) {
907 return; // Ignore node if already handled by GC.
908 }
909
910 if (n->is_Call()) {
911 // Arguments to allocation and locking don't escape.
912 if (n->is_AbstractLock()) {
913 // Put Lock and Unlock nodes on IGVN worklist to process them during
914 // first IGVN optimization when escape information is still available.
915 record_for_optimizer(n);
916 } else if (n->is_Allocate()) {
917 add_call_node(n->as_Call());
918 record_for_optimizer(n);
919 } else {
920 if (n->is_CallStaticJava()) {
921 const char* name = n->as_CallStaticJava()->_name;
922 if (name != nullptr && strcmp(name, "uncommon_trap") == 0) {
923 return; // Skip uncommon traps
924 }
925 }
926 // Don't mark as processed since call's arguments have to be processed.
927 delayed_worklist->push(n);
928 // Check if a call returns an object.
929 if ((n->as_Call()->returns_pointer() &&
930 n->as_Call()->proj_out_or_null(TypeFunc::Parms) != nullptr) ||
931 (n->is_CallStaticJava() &&
932 n->as_CallStaticJava()->is_boxing_method())) {
933 add_call_node(n->as_Call());
934 }
935 }
936 return;
937 }
938 // Put this check here to process call arguments since some call nodes
939 // point to phantom_obj.
940 if (n_ptn == phantom_obj || n_ptn == null_obj) {
941 return; // Skip predefined nodes.
942 }
943 switch (opcode) {
944 case Op_AddP: {
945 Node* base = get_addp_base(n);
946 PointsToNode* ptn_base = ptnode_adr(base->_idx);
947 // Field nodes are created for all field types. They are used in
948 // adjust_scalar_replaceable_state() and split_unique_types().
949 // Note, non-oop fields will have only base edges in Connection
950 // Graph because such fields are not used for oop loads and stores.
951 int offset = address_offset(n, igvn);
952 add_field(n, PointsToNode::NoEscape, offset);
953 if (ptn_base == nullptr) {
954 delayed_worklist->push(n); // Process it later.
955 } else {
956 n_ptn = ptnode_adr(n_idx);
957 add_base(n_ptn->as_Field(), ptn_base);
958 }
959 break;
960 }
961 case Op_CastX2P: {
962 map_ideal_node(n, phantom_obj);
963 break;
964 }
965 case Op_CastPP:
966 case Op_CheckCastPP:
967 case Op_EncodeP:
968 case Op_DecodeN:
969 case Op_EncodePKlass:
970 case Op_DecodeNKlass: {
971 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), delayed_worklist);
972 break;
973 }
974 case Op_CMoveP: {
975 add_local_var(n, PointsToNode::NoEscape);
976 // Do not add edges during first iteration because some could be
977 // not defined yet.
978 delayed_worklist->push(n);
979 break;
980 }
981 case Op_ConP:
982 case Op_ConN:
983 case Op_ConNKlass: {
984 // assume all oop constants globally escape except for null
985 PointsToNode::EscapeState es;
986 const Type* t = igvn->type(n);
987 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) {
988 es = PointsToNode::NoEscape;
989 } else {
990 es = PointsToNode::GlobalEscape;
991 }
992 PointsToNode* ptn_con = add_java_object(n, es);
993 set_not_scalar_replaceable(ptn_con NOT_PRODUCT(COMMA "Constant pointer"));
994 break;
995 }
996 case Op_CreateEx: {
997 // assume that all exception objects globally escape
998 map_ideal_node(n, phantom_obj);
999 break;
1000 }
1001 case Op_LoadKlass:
1002 case Op_LoadNKlass: {
1003 // Unknown class is loaded
1004 map_ideal_node(n, phantom_obj);
1005 break;
1006 }
1007 case Op_LoadP:
1008 case Op_LoadN: {
1009 add_objload_to_connection_graph(n, delayed_worklist);
1010 break;
1011 }
1012 case Op_Parm: {
1013 map_ideal_node(n, phantom_obj);
1014 break;
1015 }
1016 case Op_PartialSubtypeCheck: {
1017 // Produces Null or notNull and is used in only in CmpP so
1018 // phantom_obj could be used.
1019 map_ideal_node(n, phantom_obj); // Result is unknown
1020 break;
1021 }
1022 case Op_Phi: {
1023 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1024 // ThreadLocal has RawPtr type.
1025 const Type* t = n->as_Phi()->type();
1026 if (t->make_ptr() != nullptr) {
1027 add_local_var(n, PointsToNode::NoEscape);
1028 // Do not add edges during first iteration because some could be
1029 // not defined yet.
1030 delayed_worklist->push(n);
1031 }
1032 break;
1033 }
1034 case Op_Proj: {
1035 // we are only interested in the oop result projection from a call
1036 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
1037 n->in(0)->as_Call()->returns_pointer()) {
1038 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), delayed_worklist);
1039 }
1040 break;
1041 }
1042 case Op_Rethrow: // Exception object escapes
1043 case Op_Return: {
1044 if (n->req() > TypeFunc::Parms &&
1045 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
1046 // Treat Return value as LocalVar with GlobalEscape escape state.
1047 add_local_var_and_edge(n, PointsToNode::GlobalEscape, n->in(TypeFunc::Parms), delayed_worklist);
1048 }
1049 break;
1050 }
1051 case Op_CompareAndExchangeP:
1052 case Op_CompareAndExchangeN:
1053 case Op_GetAndSetP:
1054 case Op_GetAndSetN: {
1055 add_objload_to_connection_graph(n, delayed_worklist);
1056 // fall-through
1057 }
1058 case Op_StoreP:
1059 case Op_StoreN:
1060 case Op_StoreNKlass:
1061 case Op_WeakCompareAndSwapP:
1062 case Op_WeakCompareAndSwapN:
1063 case Op_CompareAndSwapP:
1064 case Op_CompareAndSwapN: {
1065 add_to_congraph_unsafe_access(n, opcode, delayed_worklist);
1066 break;
1067 }
1068 case Op_AryEq:
1069 case Op_CountPositives:
1070 case Op_StrComp:
1071 case Op_StrEquals:
1072 case Op_StrIndexOf:
1073 case Op_StrIndexOfChar:
1074 case Op_StrInflatedCopy:
1075 case Op_StrCompressedCopy:
1076 case Op_VectorizedHashCode:
1077 case Op_EncodeISOArray: {
1078 add_local_var(n, PointsToNode::ArgEscape);
1079 delayed_worklist->push(n); // Process it later.
1080 break;
1081 }
1082 case Op_ThreadLocal: {
1083 PointsToNode* ptn_thr = add_java_object(n, PointsToNode::ArgEscape);
1084 set_not_scalar_replaceable(ptn_thr NOT_PRODUCT(COMMA "Constant pointer"));
1085 break;
1086 }
1087 case Op_Blackhole: {
1088 // All blackhole pointer arguments are globally escaping.
1089 // Only do this if there is at least one pointer argument.
1090 // Do not add edges during first iteration because some could be
1091 // not defined yet, defer to final step.
1092 for (uint i = 0; i < n->req(); i++) {
1093 Node* in = n->in(i);
1094 if (in != nullptr) {
1095 const Type* at = _igvn->type(in);
1096 if (!at->isa_ptr()) continue;
1097
1098 add_local_var(n, PointsToNode::GlobalEscape);
1099 delayed_worklist->push(n);
1100 break;
1101 }
1102 }
1103 break;
1104 }
1105 default:
1106 ; // Do nothing for nodes not related to EA.
1107 }
1108 return;
1109 }
1110
1111 // Add final simple edges to graph.
1112 void ConnectionGraph::add_final_edges(Node *n) {
1113 PointsToNode* n_ptn = ptnode_adr(n->_idx);
1114 #ifdef ASSERT
1115 if (_verify && n_ptn->is_JavaObject())
1116 return; // This method does not change graph for JavaObject.
1117 #endif
1118
1119 if (n->is_Call()) {
1120 process_call_arguments(n->as_Call());
1121 return;
1122 }
1123 assert(n->is_Store() || n->is_LoadStore() ||
1124 (n_ptn != nullptr) && (n_ptn->ideal_node() != nullptr),
1125 "node should be registered already");
1126 int opcode = n->Opcode();
1127 bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_final_edges(this, _igvn, n, opcode);
1128 if (gc_handled) {
1129 return; // Ignore node if already handled by GC.
1130 }
1131 switch (opcode) {
1132 case Op_AddP: {
1133 Node* base = get_addp_base(n);
1134 PointsToNode* ptn_base = ptnode_adr(base->_idx);
1135 assert(ptn_base != nullptr, "field's base should be registered");
1136 add_base(n_ptn->as_Field(), ptn_base);
1137 break;
1138 }
1139 case Op_CastPP:
1140 case Op_CheckCastPP:
1141 case Op_EncodeP:
1142 case Op_DecodeN:
1143 case Op_EncodePKlass:
1144 case Op_DecodeNKlass: {
1145 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), nullptr);
1146 break;
1147 }
1148 case Op_CMoveP: {
1149 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) {
1150 Node* in = n->in(i);
1151 if (in == nullptr) {
1152 continue; // ignore null
1153 }
1154 Node* uncast_in = in->uncast();
1155 if (uncast_in->is_top() || uncast_in == n) {
1156 continue; // ignore top or inputs which go back this node
1157 }
1158 PointsToNode* ptn = ptnode_adr(in->_idx);
1159 assert(ptn != nullptr, "node should be registered");
1160 add_edge(n_ptn, ptn);
1161 }
1162 break;
1163 }
1164 case Op_LoadP:
1165 case Op_LoadN: {
1166 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1167 // ThreadLocal has RawPtr type.
1168 assert(_igvn->type(n)->make_ptr() != nullptr, "Unexpected node type");
1169 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(MemNode::Address), nullptr);
1170 break;
1171 }
1172 case Op_Phi: {
1173 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1174 // ThreadLocal has RawPtr type.
1175 assert(n->as_Phi()->type()->make_ptr() != nullptr, "Unexpected node type");
1176 for (uint i = 1; i < n->req(); i++) {
1177 Node* in = n->in(i);
1178 if (in == nullptr) {
1179 continue; // ignore null
1180 }
1181 Node* uncast_in = in->uncast();
1182 if (uncast_in->is_top() || uncast_in == n) {
1183 continue; // ignore top or inputs which go back this node
1184 }
1185 PointsToNode* ptn = ptnode_adr(in->_idx);
1186 assert(ptn != nullptr, "node should be registered");
1187 add_edge(n_ptn, ptn);
1188 }
1189 break;
1190 }
1191 case Op_Proj: {
1192 // we are only interested in the oop result projection from a call
1193 assert(n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
1194 n->in(0)->as_Call()->returns_pointer(), "Unexpected node type");
1195 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), nullptr);
1196 break;
1197 }
1198 case Op_Rethrow: // Exception object escapes
1199 case Op_Return: {
1200 assert(n->req() > TypeFunc::Parms && _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr(),
1201 "Unexpected node type");
1202 // Treat Return value as LocalVar with GlobalEscape escape state.
1203 add_local_var_and_edge(n, PointsToNode::GlobalEscape, n->in(TypeFunc::Parms), nullptr);
1204 break;
1205 }
1206 case Op_CompareAndExchangeP:
1207 case Op_CompareAndExchangeN:
1208 case Op_GetAndSetP:
1209 case Op_GetAndSetN:{
1210 assert(_igvn->type(n)->make_ptr() != nullptr, "Unexpected node type");
1211 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(MemNode::Address), nullptr);
1212 // fall-through
1213 }
1214 case Op_CompareAndSwapP:
1215 case Op_CompareAndSwapN:
1216 case Op_WeakCompareAndSwapP:
1217 case Op_WeakCompareAndSwapN:
1218 case Op_StoreP:
1219 case Op_StoreN:
1220 case Op_StoreNKlass:{
1221 add_final_edges_unsafe_access(n, opcode);
1222 break;
1223 }
1224 case Op_VectorizedHashCode:
1225 case Op_AryEq:
1226 case Op_CountPositives:
1227 case Op_StrComp:
1228 case Op_StrEquals:
1229 case Op_StrIndexOf:
1230 case Op_StrIndexOfChar:
1231 case Op_StrInflatedCopy:
1232 case Op_StrCompressedCopy:
1233 case Op_EncodeISOArray: {
1234 // char[]/byte[] arrays passed to string intrinsic do not escape but
1235 // they are not scalar replaceable. Adjust escape state for them.
1236 // Start from in(2) edge since in(1) is memory edge.
1237 for (uint i = 2; i < n->req(); i++) {
1238 Node* adr = n->in(i);
1239 const Type* at = _igvn->type(adr);
1240 if (!adr->is_top() && at->isa_ptr()) {
1241 assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
1242 at->isa_ptr() != nullptr, "expecting a pointer");
1243 if (adr->is_AddP()) {
1244 adr = get_addp_base(adr);
1245 }
1246 PointsToNode* ptn = ptnode_adr(adr->_idx);
1247 assert(ptn != nullptr, "node should be registered");
1248 add_edge(n_ptn, ptn);
1249 }
1250 }
1251 break;
1252 }
1253 case Op_Blackhole: {
1254 // All blackhole pointer arguments are globally escaping.
1255 for (uint i = 0; i < n->req(); i++) {
1256 Node* in = n->in(i);
1257 if (in != nullptr) {
1258 const Type* at = _igvn->type(in);
1259 if (!at->isa_ptr()) continue;
1260
1261 if (in->is_AddP()) {
1262 in = get_addp_base(in);
1263 }
1264
1265 PointsToNode* ptn = ptnode_adr(in->_idx);
1266 assert(ptn != nullptr, "should be defined already");
1267 set_escape_state(ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA "blackhole"));
1268 add_edge(n_ptn, ptn);
1269 }
1270 }
1271 break;
1272 }
1273 default: {
1274 // This method should be called only for EA specific nodes which may
1275 // miss some edges when they were created.
1276 #ifdef ASSERT
1277 n->dump(1);
1278 #endif
1279 guarantee(false, "unknown node");
1280 }
1281 }
1282 return;
1283 }
1284
1285 void ConnectionGraph::add_to_congraph_unsafe_access(Node* n, uint opcode, Unique_Node_List* delayed_worklist) {
1286 Node* adr = n->in(MemNode::Address);
1287 const Type* adr_type = _igvn->type(adr);
1288 adr_type = adr_type->make_ptr();
1289 if (adr_type == nullptr) {
1290 return; // skip dead nodes
1291 }
1292 if (adr_type->isa_oopptr()
1293 || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
1294 && adr_type == TypeRawPtr::NOTNULL
1295 && is_captured_store_address(adr))) {
1296 delayed_worklist->push(n); // Process it later.
1297 #ifdef ASSERT
1298 assert (adr->is_AddP(), "expecting an AddP");
1299 if (adr_type == TypeRawPtr::NOTNULL) {
1300 // Verify a raw address for a store captured by Initialize node.
1301 int offs = (int) _igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
1302 assert(offs != Type::OffsetBot, "offset must be a constant");
1303 }
1304 #endif
1305 } else {
1306 // Ignore copy the displaced header to the BoxNode (OSR compilation).
1307 if (adr->is_BoxLock()) {
1308 return;
1309 }
1310 // Stored value escapes in unsafe access.
1311 if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
1312 delayed_worklist->push(n); // Process unsafe access later.
1313 return;
1314 }
1315 #ifdef ASSERT
1316 n->dump(1);
1317 assert(false, "not unsafe");
1318 #endif
1319 }
1320 }
1321
1322 bool ConnectionGraph::add_final_edges_unsafe_access(Node* n, uint opcode) {
1323 Node* adr = n->in(MemNode::Address);
1324 const Type *adr_type = _igvn->type(adr);
1325 adr_type = adr_type->make_ptr();
1326 #ifdef ASSERT
1327 if (adr_type == nullptr) {
1328 n->dump(1);
1329 assert(adr_type != nullptr, "dead node should not be on list");
1330 return true;
1331 }
1332 #endif
1333
1334 if (adr_type->isa_oopptr()
1335 || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
1336 && adr_type == TypeRawPtr::NOTNULL
1337 && is_captured_store_address(adr))) {
1338 // Point Address to Value
1339 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
1340 assert(adr_ptn != nullptr &&
1341 adr_ptn->as_Field()->is_oop(), "node should be registered");
1342 Node* val = n->in(MemNode::ValueIn);
1343 PointsToNode* ptn = ptnode_adr(val->_idx);
1344 assert(ptn != nullptr, "node should be registered");
1345 add_edge(adr_ptn, ptn);
1346 return true;
1347 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
1348 // Stored value escapes in unsafe access.
1349 Node* val = n->in(MemNode::ValueIn);
1350 PointsToNode* ptn = ptnode_adr(val->_idx);
1351 assert(ptn != nullptr, "node should be registered");
1352 set_escape_state(ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA "stored at raw address"));
1353 // Add edge to object for unsafe access with offset.
1354 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
1355 assert(adr_ptn != nullptr, "node should be registered");
1356 if (adr_ptn->is_Field()) {
1357 assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
1358 add_edge(adr_ptn, ptn);
1359 }
1360 return true;
1361 }
1362 #ifdef ASSERT
1363 n->dump(1);
1364 assert(false, "not unsafe");
1365 #endif
1366 return false;
1367 }
1368
1369 void ConnectionGraph::add_call_node(CallNode* call) {
1370 assert(call->returns_pointer(), "only for call which returns pointer");
1371 uint call_idx = call->_idx;
1372 if (call->is_Allocate()) {
1373 Node* k = call->in(AllocateNode::KlassNode);
1374 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr();
1375 assert(kt != nullptr, "TypeKlassPtr required.");
1376 PointsToNode::EscapeState es = PointsToNode::NoEscape;
1377 bool scalar_replaceable = true;
1378 NOT_PRODUCT(const char* nsr_reason = "");
1379 if (call->is_AllocateArray()) {
1380 if (!kt->isa_aryklassptr()) { // StressReflectiveCode
1381 es = PointsToNode::GlobalEscape;
1382 } else {
1383 int length = call->in(AllocateNode::ALength)->find_int_con(-1);
1384 if (length < 0) {
1385 // Not scalar replaceable if the length is not constant.
1386 scalar_replaceable = false;
1387 NOT_PRODUCT(nsr_reason = "has a non-constant length");
1388 } else if (length > EliminateAllocationArraySizeLimit) {
1389 // Not scalar replaceable if the length is too big.
1390 scalar_replaceable = false;
1391 NOT_PRODUCT(nsr_reason = "has a length that is too big");
1392 }
1393 }
1394 } else { // Allocate instance
1395 if (!kt->isa_instklassptr()) { // StressReflectiveCode
1396 es = PointsToNode::GlobalEscape;
1397 } else {
1398 const TypeInstKlassPtr* ikt = kt->is_instklassptr();
1399 ciInstanceKlass* ik = ikt->klass_is_exact() ? ikt->exact_klass()->as_instance_klass() : ikt->instance_klass();
1400 if (ik->is_subclass_of(_compile->env()->Thread_klass()) ||
1401 ik->is_subclass_of(_compile->env()->Reference_klass()) ||
1402 !ik->can_be_instantiated() ||
1403 ik->has_finalizer()) {
1404 es = PointsToNode::GlobalEscape;
1405 } else {
1406 int nfields = ik->as_instance_klass()->nof_nonstatic_fields();
1407 if (nfields > EliminateAllocationFieldsLimit) {
1408 // Not scalar replaceable if there are too many fields.
1409 scalar_replaceable = false;
1410 NOT_PRODUCT(nsr_reason = "has too many fields");
1411 }
1412 }
1413 }
1414 }
1415 add_java_object(call, es);
1416 PointsToNode* ptn = ptnode_adr(call_idx);
1417 if (!scalar_replaceable && ptn->scalar_replaceable()) {
1418 set_not_scalar_replaceable(ptn NOT_PRODUCT(COMMA nsr_reason));
1419 }
1420 } else if (call->is_CallStaticJava()) {
1421 // Call nodes could be different types:
1422 //
1423 // 1. CallDynamicJavaNode (what happened during call is unknown):
1424 //
1425 // - mapped to GlobalEscape JavaObject node if oop is returned;
1426 //
1427 // - all oop arguments are escaping globally;
1428 //
1429 // 2. CallStaticJavaNode (execute bytecode analysis if possible):
1430 //
1431 // - the same as CallDynamicJavaNode if can't do bytecode analysis;
1432 //
1433 // - mapped to GlobalEscape JavaObject node if unknown oop is returned;
1434 // - mapped to NoEscape JavaObject node if non-escaping object allocated
1435 // during call is returned;
1436 // - mapped to ArgEscape LocalVar node pointed to object arguments
1437 // which are returned and does not escape during call;
1438 //
1439 // - oop arguments escaping status is defined by bytecode analysis;
1440 //
1441 // For a static call, we know exactly what method is being called.
1442 // Use bytecode estimator to record whether the call's return value escapes.
1443 ciMethod* meth = call->as_CallJava()->method();
1444 if (meth == nullptr) {
1445 const char* name = call->as_CallStaticJava()->_name;
1446 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check");
1447 // Returns a newly allocated non-escaped object.
1448 add_java_object(call, PointsToNode::NoEscape);
1449 set_not_scalar_replaceable(ptnode_adr(call_idx) NOT_PRODUCT(COMMA "is result of multinewarray"));
1450 } else if (meth->is_boxing_method()) {
1451 // Returns boxing object
1452 PointsToNode::EscapeState es;
1453 vmIntrinsics::ID intr = meth->intrinsic_id();
1454 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) {
1455 // It does not escape if object is always allocated.
1456 es = PointsToNode::NoEscape;
1457 } else {
1458 // It escapes globally if object could be loaded from cache.
1459 es = PointsToNode::GlobalEscape;
1460 }
1461 add_java_object(call, es);
1462 if (es == PointsToNode::GlobalEscape) {
1463 set_not_scalar_replaceable(ptnode_adr(call->_idx) NOT_PRODUCT(COMMA "object can be loaded from boxing cache"));
1464 }
1465 } else {
1466 BCEscapeAnalyzer* call_analyzer = meth->get_bcea();
1467 call_analyzer->copy_dependencies(_compile->dependencies());
1468 if (call_analyzer->is_return_allocated()) {
1469 // Returns a newly allocated non-escaped object, simply
1470 // update dependency information.
1471 // Mark it as NoEscape so that objects referenced by
1472 // it's fields will be marked as NoEscape at least.
1473 add_java_object(call, PointsToNode::NoEscape);
1474 set_not_scalar_replaceable(ptnode_adr(call_idx) NOT_PRODUCT(COMMA "is result of call"));
1475 } else {
1476 // Determine whether any arguments are returned.
1477 const TypeTuple* d = call->tf()->domain();
1478 bool ret_arg = false;
1479 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1480 if (d->field_at(i)->isa_ptr() != nullptr &&
1481 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
1482 ret_arg = true;
1483 break;
1484 }
1485 }
1486 if (ret_arg) {
1487 add_local_var(call, PointsToNode::ArgEscape);
1488 } else {
1489 // Returns unknown object.
1490 map_ideal_node(call, phantom_obj);
1491 }
1492 }
1493 }
1494 } else {
1495 // An other type of call, assume the worst case:
1496 // returned value is unknown and globally escapes.
1497 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check");
1498 map_ideal_node(call, phantom_obj);
1499 }
1500 }
1501
1502 void ConnectionGraph::process_call_arguments(CallNode *call) {
1503 bool is_arraycopy = false;
1504 switch (call->Opcode()) {
1505 #ifdef ASSERT
1506 case Op_Allocate:
1507 case Op_AllocateArray:
1508 case Op_Lock:
1509 case Op_Unlock:
1510 assert(false, "should be done already");
1511 break;
1512 #endif
1513 case Op_ArrayCopy:
1514 case Op_CallLeafNoFP:
1515 // Most array copies are ArrayCopy nodes at this point but there
1516 // are still a few direct calls to the copy subroutines (See
1517 // PhaseStringOpts::copy_string())
1518 is_arraycopy = (call->Opcode() == Op_ArrayCopy) ||
1519 call->as_CallLeaf()->is_call_to_arraycopystub();
1520 // fall through
1521 case Op_CallLeafVector:
1522 case Op_CallLeaf: {
1523 // Stub calls, objects do not escape but they are not scale replaceable.
1524 // Adjust escape state for outgoing arguments.
1525 const TypeTuple * d = call->tf()->domain();
1526 bool src_has_oops = false;
1527 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1528 const Type* at = d->field_at(i);
1529 Node *arg = call->in(i);
1530 if (arg == nullptr) {
1531 continue;
1532 }
1533 const Type *aat = _igvn->type(arg);
1534 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) {
1535 continue;
1536 }
1537 if (arg->is_AddP()) {
1538 //
1539 // The inline_native_clone() case when the arraycopy stub is called
1540 // after the allocation before Initialize and CheckCastPP nodes.
1541 // Or normal arraycopy for object arrays case.
1542 //
1543 // Set AddP's base (Allocate) as not scalar replaceable since
1544 // pointer to the base (with offset) is passed as argument.
1545 //
1546 arg = get_addp_base(arg);
1547 }
1548 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1549 assert(arg_ptn != nullptr, "should be registered");
1550 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state();
1551 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) {
1552 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
1553 aat->isa_ptr() != nullptr, "expecting an Ptr");
1554 bool arg_has_oops = aat->isa_oopptr() &&
1555 (aat->isa_instptr() ||
1556 (aat->isa_aryptr() && (aat->isa_aryptr()->elem() == Type::BOTTOM || aat->isa_aryptr()->elem()->make_oopptr() != nullptr)));
1557 if (i == TypeFunc::Parms) {
1558 src_has_oops = arg_has_oops;
1559 }
1560 //
1561 // src or dst could be j.l.Object when other is basic type array:
1562 //
1563 // arraycopy(char[],0,Object*,0,size);
1564 // arraycopy(Object*,0,char[],0,size);
1565 //
1566 // Don't add edges in such cases.
1567 //
1568 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy &&
1569 arg_has_oops && (i > TypeFunc::Parms);
1570 #ifdef ASSERT
1571 if (!(is_arraycopy ||
1572 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(call) ||
1573 (call->as_CallLeaf()->_name != nullptr &&
1574 (strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 ||
1575 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 ||
1576 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 ||
1577 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 ||
1578 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 ||
1579 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 ||
1580 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 ||
1581 strcmp(call->as_CallLeaf()->_name, "electronicCodeBook_encryptAESCrypt") == 0 ||
1582 strcmp(call->as_CallLeaf()->_name, "electronicCodeBook_decryptAESCrypt") == 0 ||
1583 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 ||
1584 strcmp(call->as_CallLeaf()->_name, "galoisCounterMode_AESCrypt") == 0 ||
1585 strcmp(call->as_CallLeaf()->_name, "poly1305_processBlocks") == 0 ||
1586 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 ||
1587 strcmp(call->as_CallLeaf()->_name, "chacha20Block") == 0 ||
1588 strcmp(call->as_CallLeaf()->_name, "encodeBlock") == 0 ||
1589 strcmp(call->as_CallLeaf()->_name, "decodeBlock") == 0 ||
1590 strcmp(call->as_CallLeaf()->_name, "md5_implCompress") == 0 ||
1591 strcmp(call->as_CallLeaf()->_name, "md5_implCompressMB") == 0 ||
1592 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 ||
1593 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 ||
1594 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 ||
1595 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 ||
1596 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 ||
1597 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 ||
1598 strcmp(call->as_CallLeaf()->_name, "sha3_implCompress") == 0 ||
1599 strcmp(call->as_CallLeaf()->_name, "sha3_implCompressMB") == 0 ||
1600 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 ||
1601 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 ||
1602 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 ||
1603 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 ||
1604 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 ||
1605 strcmp(call->as_CallLeaf()->_name, "bigIntegerRightShiftWorker") == 0 ||
1606 strcmp(call->as_CallLeaf()->_name, "bigIntegerLeftShiftWorker") == 0 ||
1607 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0 ||
1608 strcmp(call->as_CallLeaf()->_name, "arraysort_stub") == 0 ||
1609 strcmp(call->as_CallLeaf()->_name, "array_partition_stub") == 0 ||
1610 strcmp(call->as_CallLeaf()->_name, "get_class_id_intrinsic") == 0)
1611 ))) {
1612 call->dump();
1613 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name);
1614 }
1615 #endif
1616 // Always process arraycopy's destination object since
1617 // we need to add all possible edges to references in
1618 // source object.
1619 if (arg_esc >= PointsToNode::ArgEscape &&
1620 !arg_is_arraycopy_dest) {
1621 continue;
1622 }
1623 PointsToNode::EscapeState es = PointsToNode::ArgEscape;
1624 if (call->is_ArrayCopy()) {
1625 ArrayCopyNode* ac = call->as_ArrayCopy();
1626 if (ac->is_clonebasic() ||
1627 ac->is_arraycopy_validated() ||
1628 ac->is_copyof_validated() ||
1629 ac->is_copyofrange_validated()) {
1630 es = PointsToNode::NoEscape;
1631 }
1632 }
1633 set_escape_state(arg_ptn, es NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1634 if (arg_is_arraycopy_dest) {
1635 Node* src = call->in(TypeFunc::Parms);
1636 if (src->is_AddP()) {
1637 src = get_addp_base(src);
1638 }
1639 PointsToNode* src_ptn = ptnode_adr(src->_idx);
1640 assert(src_ptn != nullptr, "should be registered");
1641 if (arg_ptn != src_ptn) {
1642 // Special arraycopy edge:
1643 // A destination object's field can't have the source object
1644 // as base since objects escape states are not related.
1645 // Only escape state of destination object's fields affects
1646 // escape state of fields in source object.
1647 add_arraycopy(call, es, src_ptn, arg_ptn);
1648 }
1649 }
1650 }
1651 }
1652 break;
1653 }
1654 case Op_CallStaticJava: {
1655 // For a static call, we know exactly what method is being called.
1656 // Use bytecode estimator to record the call's escape affects
1657 #ifdef ASSERT
1658 const char* name = call->as_CallStaticJava()->_name;
1659 assert((name == nullptr || strcmp(name, "uncommon_trap") != 0), "normal calls only");
1660 #endif
1661 ciMethod* meth = call->as_CallJava()->method();
1662 if ((meth != nullptr) && meth->is_boxing_method()) {
1663 break; // Boxing methods do not modify any oops.
1664 }
1665 BCEscapeAnalyzer* call_analyzer = (meth !=nullptr) ? meth->get_bcea() : nullptr;
1666 // fall-through if not a Java method or no analyzer information
1667 if (call_analyzer != nullptr) {
1668 PointsToNode* call_ptn = ptnode_adr(call->_idx);
1669 const TypeTuple* d = call->tf()->domain();
1670 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1671 const Type* at = d->field_at(i);
1672 int k = i - TypeFunc::Parms;
1673 Node* arg = call->in(i);
1674 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1675 if (at->isa_ptr() != nullptr &&
1676 call_analyzer->is_arg_returned(k)) {
1677 // The call returns arguments.
1678 if (call_ptn != nullptr) { // Is call's result used?
1679 assert(call_ptn->is_LocalVar(), "node should be registered");
1680 assert(arg_ptn != nullptr, "node should be registered");
1681 add_edge(call_ptn, arg_ptn);
1682 }
1683 }
1684 if (at->isa_oopptr() != nullptr &&
1685 arg_ptn->escape_state() < PointsToNode::GlobalEscape) {
1686 if (!call_analyzer->is_arg_stack(k)) {
1687 // The argument global escapes
1688 set_escape_state(arg_ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1689 } else {
1690 set_escape_state(arg_ptn, PointsToNode::ArgEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1691 if (!call_analyzer->is_arg_local(k)) {
1692 // The argument itself doesn't escape, but any fields might
1693 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1694 }
1695 }
1696 }
1697 }
1698 if (call_ptn != nullptr && call_ptn->is_LocalVar()) {
1699 // The call returns arguments.
1700 assert(call_ptn->edge_count() > 0, "sanity");
1701 if (!call_analyzer->is_return_local()) {
1702 // Returns also unknown object.
1703 add_edge(call_ptn, phantom_obj);
1704 }
1705 }
1706 break;
1707 }
1708 }
1709 default: {
1710 // Fall-through here if not a Java method or no analyzer information
1711 // or some other type of call, assume the worst case: all arguments
1712 // globally escape.
1713 const TypeTuple* d = call->tf()->domain();
1714 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1715 const Type* at = d->field_at(i);
1716 if (at->isa_oopptr() != nullptr) {
1717 Node* arg = call->in(i);
1718 if (arg->is_AddP()) {
1719 arg = get_addp_base(arg);
1720 }
1721 assert(ptnode_adr(arg->_idx) != nullptr, "should be defined already");
1722 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
1723 }
1724 }
1725 }
1726 }
1727 }
1728
1729
1730 // Finish Graph construction.
1731 bool ConnectionGraph::complete_connection_graph(
1732 GrowableArray<PointsToNode*>& ptnodes_worklist,
1733 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist,
1734 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1735 GrowableArray<FieldNode*>& oop_fields_worklist) {
1736 // Normally only 1-3 passes needed to build Connection Graph depending
1737 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler.
1738 // Set limit to 20 to catch situation when something did go wrong and
1739 // bailout Escape Analysis.
1740 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag.
1741 #define GRAPH_BUILD_ITER_LIMIT 20
1742
1743 // Propagate GlobalEscape and ArgEscape escape states and check that
1744 // we still have non-escaping objects. The method pushs on _worklist
1745 // Field nodes which reference phantom_object.
1746 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist)) {
1747 return false; // Nothing to do.
1748 }
1749 // Now propagate references to all JavaObject nodes.
1750 int java_objects_length = java_objects_worklist.length();
1751 elapsedTimer build_time;
1752 build_time.start();
1753 elapsedTimer time;
1754 bool timeout = false;
1755 int new_edges = 1;
1756 int iterations = 0;
1757 do {
1758 while ((new_edges > 0) &&
1759 (iterations++ < GRAPH_BUILD_ITER_LIMIT)) {
1760 double start_time = time.seconds();
1761 time.start();
1762 new_edges = 0;
1763 // Propagate references to phantom_object for nodes pushed on _worklist
1764 // by find_non_escaped_objects() and find_field_value().
1765 new_edges += add_java_object_edges(phantom_obj, false);
1766 for (int next = 0; next < java_objects_length; ++next) {
1767 JavaObjectNode* ptn = java_objects_worklist.at(next);
1768 new_edges += add_java_object_edges(ptn, true);
1769
1770 #define SAMPLE_SIZE 4
1771 if ((next % SAMPLE_SIZE) == 0) {
1772 // Each 4 iterations calculate how much time it will take
1773 // to complete graph construction.
1774 time.stop();
1775 // Poll for requests from shutdown mechanism to quiesce compiler
1776 // because Connection graph construction may take long time.
1777 CompileBroker::maybe_block();
1778 double stop_time = time.seconds();
1779 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE;
1780 double time_until_end = time_per_iter * (double)(java_objects_length - next);
1781 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) {
1782 timeout = true;
1783 break; // Timeout
1784 }
1785 start_time = stop_time;
1786 time.start();
1787 }
1788 #undef SAMPLE_SIZE
1789
1790 }
1791 if (timeout) break;
1792 if (new_edges > 0) {
1793 // Update escape states on each iteration if graph was updated.
1794 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist)) {
1795 return false; // Nothing to do.
1796 }
1797 }
1798 time.stop();
1799 if (time.seconds() >= EscapeAnalysisTimeout) {
1800 timeout = true;
1801 break;
1802 }
1803 }
1804 if ((iterations < GRAPH_BUILD_ITER_LIMIT) && !timeout) {
1805 time.start();
1806 // Find fields which have unknown value.
1807 int fields_length = oop_fields_worklist.length();
1808 for (int next = 0; next < fields_length; next++) {
1809 FieldNode* field = oop_fields_worklist.at(next);
1810 if (field->edge_count() == 0) {
1811 new_edges += find_field_value(field);
1812 // This code may added new edges to phantom_object.
1813 // Need an other cycle to propagate references to phantom_object.
1814 }
1815 }
1816 time.stop();
1817 if (time.seconds() >= EscapeAnalysisTimeout) {
1818 timeout = true;
1819 break;
1820 }
1821 } else {
1822 new_edges = 0; // Bailout
1823 }
1824 } while (new_edges > 0);
1825
1826 build_time.stop();
1827 _build_time = build_time.seconds();
1828 _build_iterations = iterations;
1829
1830 // Bailout if passed limits.
1831 if ((iterations >= GRAPH_BUILD_ITER_LIMIT) || timeout) {
1832 Compile* C = _compile;
1833 if (C->log() != nullptr) {
1834 C->log()->begin_elem("connectionGraph_bailout reason='reached ");
1835 C->log()->text("%s", timeout ? "time" : "iterations");
1836 C->log()->end_elem(" limit'");
1837 }
1838 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build during invocation %d (%f sec, %d iterations) with %d nodes and worklist size %d",
1839 _invocation, _build_time, _build_iterations, nodes_size(), ptnodes_worklist.length());
1840 // Possible infinite build_connection_graph loop,
1841 // bailout (no changes to ideal graph were made).
1842 return false;
1843 }
1844
1845 #undef GRAPH_BUILD_ITER_LIMIT
1846
1847 // Find fields initialized by null for non-escaping Allocations.
1848 int non_escaped_length = non_escaped_allocs_worklist.length();
1849 for (int next = 0; next < non_escaped_length; next++) {
1850 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
1851 PointsToNode::EscapeState es = ptn->escape_state();
1852 assert(es <= PointsToNode::ArgEscape, "sanity");
1853 if (es == PointsToNode::NoEscape) {
1854 if (find_init_values_null(ptn, _igvn) > 0) {
1855 // Adding references to null object does not change escape states
1856 // since it does not escape. Also no fields are added to null object.
1857 add_java_object_edges(null_obj, false);
1858 }
1859 }
1860 Node* n = ptn->ideal_node();
1861 if (n->is_Allocate()) {
1862 // The object allocated by this Allocate node will never be
1863 // seen by an other thread. Mark it so that when it is
1864 // expanded no MemBarStoreStore is added.
1865 InitializeNode* ini = n->as_Allocate()->initialization();
1866 if (ini != nullptr)
1867 ini->set_does_not_escape();
1868 }
1869 }
1870 return true; // Finished graph construction.
1871 }
1872
1873 // Propagate GlobalEscape and ArgEscape escape states to all nodes
1874 // and check that we still have non-escaping java objects.
1875 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist,
1876 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist) {
1877 GrowableArray<PointsToNode*> escape_worklist;
1878 // First, put all nodes with GlobalEscape and ArgEscape states on worklist.
1879 int ptnodes_length = ptnodes_worklist.length();
1880 for (int next = 0; next < ptnodes_length; ++next) {
1881 PointsToNode* ptn = ptnodes_worklist.at(next);
1882 if (ptn->escape_state() >= PointsToNode::ArgEscape ||
1883 ptn->fields_escape_state() >= PointsToNode::ArgEscape) {
1884 escape_worklist.push(ptn);
1885 }
1886 }
1887 // Set escape states to referenced nodes (edges list).
1888 while (escape_worklist.length() > 0) {
1889 PointsToNode* ptn = escape_worklist.pop();
1890 PointsToNode::EscapeState es = ptn->escape_state();
1891 PointsToNode::EscapeState field_es = ptn->fields_escape_state();
1892 if (ptn->is_Field() && ptn->as_Field()->is_oop() &&
1893 es >= PointsToNode::ArgEscape) {
1894 // GlobalEscape or ArgEscape state of field means it has unknown value.
1895 if (add_edge(ptn, phantom_obj)) {
1896 // New edge was added
1897 add_field_uses_to_worklist(ptn->as_Field());
1898 }
1899 }
1900 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1901 PointsToNode* e = i.get();
1902 if (e->is_Arraycopy()) {
1903 assert(ptn->arraycopy_dst(), "sanity");
1904 // Propagate only fields escape state through arraycopy edge.
1905 if (e->fields_escape_state() < field_es) {
1906 set_fields_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1907 escape_worklist.push(e);
1908 }
1909 } else if (es >= field_es) {
1910 // fields_escape_state is also set to 'es' if it is less than 'es'.
1911 if (e->escape_state() < es) {
1912 set_escape_state(e, es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1913 escape_worklist.push(e);
1914 }
1915 } else {
1916 // Propagate field escape state.
1917 bool es_changed = false;
1918 if (e->fields_escape_state() < field_es) {
1919 set_fields_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1920 es_changed = true;
1921 }
1922 if ((e->escape_state() < field_es) &&
1923 e->is_Field() && ptn->is_JavaObject() &&
1924 e->as_Field()->is_oop()) {
1925 // Change escape state of referenced fields.
1926 set_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1927 es_changed = true;
1928 } else if (e->escape_state() < es) {
1929 set_escape_state(e, es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
1930 es_changed = true;
1931 }
1932 if (es_changed) {
1933 escape_worklist.push(e);
1934 }
1935 }
1936 }
1937 }
1938 // Remove escaped objects from non_escaped list.
1939 for (int next = non_escaped_allocs_worklist.length()-1; next >= 0 ; --next) {
1940 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
1941 if (ptn->escape_state() >= PointsToNode::GlobalEscape) {
1942 non_escaped_allocs_worklist.delete_at(next);
1943 }
1944 if (ptn->escape_state() == PointsToNode::NoEscape) {
1945 // Find fields in non-escaped allocations which have unknown value.
1946 find_init_values_phantom(ptn);
1947 }
1948 }
1949 return (non_escaped_allocs_worklist.length() > 0);
1950 }
1951
1952 // Add all references to JavaObject node by walking over all uses.
1953 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) {
1954 int new_edges = 0;
1955 if (populate_worklist) {
1956 // Populate _worklist by uses of jobj's uses.
1957 for (UseIterator i(jobj); i.has_next(); i.next()) {
1958 PointsToNode* use = i.get();
1959 if (use->is_Arraycopy()) {
1960 continue;
1961 }
1962 add_uses_to_worklist(use);
1963 if (use->is_Field() && use->as_Field()->is_oop()) {
1964 // Put on worklist all field's uses (loads) and
1965 // related field nodes (same base and offset).
1966 add_field_uses_to_worklist(use->as_Field());
1967 }
1968 }
1969 }
1970 for (int l = 0; l < _worklist.length(); l++) {
1971 PointsToNode* use = _worklist.at(l);
1972 if (PointsToNode::is_base_use(use)) {
1973 // Add reference from jobj to field and from field to jobj (field's base).
1974 use = PointsToNode::get_use_node(use)->as_Field();
1975 if (add_base(use->as_Field(), jobj)) {
1976 new_edges++;
1977 }
1978 continue;
1979 }
1980 assert(!use->is_JavaObject(), "sanity");
1981 if (use->is_Arraycopy()) {
1982 if (jobj == null_obj) { // null object does not have field edges
1983 continue;
1984 }
1985 // Added edge from Arraycopy node to arraycopy's source java object
1986 if (add_edge(use, jobj)) {
1987 jobj->set_arraycopy_src();
1988 new_edges++;
1989 }
1990 // and stop here.
1991 continue;
1992 }
1993 if (!add_edge(use, jobj)) {
1994 continue; // No new edge added, there was such edge already.
1995 }
1996 new_edges++;
1997 if (use->is_LocalVar()) {
1998 add_uses_to_worklist(use);
1999 if (use->arraycopy_dst()) {
2000 for (EdgeIterator i(use); i.has_next(); i.next()) {
2001 PointsToNode* e = i.get();
2002 if (e->is_Arraycopy()) {
2003 if (jobj == null_obj) { // null object does not have field edges
2004 continue;
2005 }
2006 // Add edge from arraycopy's destination java object to Arraycopy node.
2007 if (add_edge(jobj, e)) {
2008 new_edges++;
2009 jobj->set_arraycopy_dst();
2010 }
2011 }
2012 }
2013 }
2014 } else {
2015 // Added new edge to stored in field values.
2016 // Put on worklist all field's uses (loads) and
2017 // related field nodes (same base and offset).
2018 add_field_uses_to_worklist(use->as_Field());
2019 }
2020 }
2021 _worklist.clear();
2022 _in_worklist.reset();
2023 return new_edges;
2024 }
2025
2026 // Put on worklist all related field nodes.
2027 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) {
2028 assert(field->is_oop(), "sanity");
2029 int offset = field->offset();
2030 add_uses_to_worklist(field);
2031 // Loop over all bases of this field and push on worklist Field nodes
2032 // with the same offset and base (since they may reference the same field).
2033 for (BaseIterator i(field); i.has_next(); i.next()) {
2034 PointsToNode* base = i.get();
2035 add_fields_to_worklist(field, base);
2036 // Check if the base was source object of arraycopy and go over arraycopy's
2037 // destination objects since values stored to a field of source object are
2038 // accessible by uses (loads) of fields of destination objects.
2039 if (base->arraycopy_src()) {
2040 for (UseIterator j(base); j.has_next(); j.next()) {
2041 PointsToNode* arycp = j.get();
2042 if (arycp->is_Arraycopy()) {
2043 for (UseIterator k(arycp); k.has_next(); k.next()) {
2044 PointsToNode* abase = k.get();
2045 if (abase->arraycopy_dst() && abase != base) {
2046 // Look for the same arraycopy reference.
2047 add_fields_to_worklist(field, abase);
2048 }
2049 }
2050 }
2051 }
2052 }
2053 }
2054 }
2055
2056 // Put on worklist all related field nodes.
2057 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) {
2058 int offset = field->offset();
2059 if (base->is_LocalVar()) {
2060 for (UseIterator j(base); j.has_next(); j.next()) {
2061 PointsToNode* f = j.get();
2062 if (PointsToNode::is_base_use(f)) { // Field
2063 f = PointsToNode::get_use_node(f);
2064 if (f == field || !f->as_Field()->is_oop()) {
2065 continue;
2066 }
2067 int offs = f->as_Field()->offset();
2068 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
2069 add_to_worklist(f);
2070 }
2071 }
2072 }
2073 } else {
2074 assert(base->is_JavaObject(), "sanity");
2075 if (// Skip phantom_object since it is only used to indicate that
2076 // this field's content globally escapes.
2077 (base != phantom_obj) &&
2078 // null object node does not have fields.
2079 (base != null_obj)) {
2080 for (EdgeIterator i(base); i.has_next(); i.next()) {
2081 PointsToNode* f = i.get();
2082 // Skip arraycopy edge since store to destination object field
2083 // does not update value in source object field.
2084 if (f->is_Arraycopy()) {
2085 assert(base->arraycopy_dst(), "sanity");
2086 continue;
2087 }
2088 if (f == field || !f->as_Field()->is_oop()) {
2089 continue;
2090 }
2091 int offs = f->as_Field()->offset();
2092 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
2093 add_to_worklist(f);
2094 }
2095 }
2096 }
2097 }
2098 }
2099
2100 // Find fields which have unknown value.
2101 int ConnectionGraph::find_field_value(FieldNode* field) {
2102 // Escaped fields should have init value already.
2103 assert(field->escape_state() == PointsToNode::NoEscape, "sanity");
2104 int new_edges = 0;
2105 for (BaseIterator i(field); i.has_next(); i.next()) {
2106 PointsToNode* base = i.get();
2107 if (base->is_JavaObject()) {
2108 // Skip Allocate's fields which will be processed later.
2109 if (base->ideal_node()->is_Allocate()) {
2110 return 0;
2111 }
2112 assert(base == null_obj, "only null ptr base expected here");
2113 }
2114 }
2115 if (add_edge(field, phantom_obj)) {
2116 // New edge was added
2117 new_edges++;
2118 add_field_uses_to_worklist(field);
2119 }
2120 return new_edges;
2121 }
2122
2123 // Find fields initializing values for allocations.
2124 int ConnectionGraph::find_init_values_phantom(JavaObjectNode* pta) {
2125 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
2126 Node* alloc = pta->ideal_node();
2127
2128 // Do nothing for Allocate nodes since its fields values are
2129 // "known" unless they are initialized by arraycopy/clone.
2130 if (alloc->is_Allocate() && !pta->arraycopy_dst()) {
2131 return 0;
2132 }
2133 assert(pta->arraycopy_dst() || alloc->as_CallStaticJava(), "sanity");
2134 #ifdef ASSERT
2135 if (!pta->arraycopy_dst() && alloc->as_CallStaticJava()->method() == nullptr) {
2136 const char* name = alloc->as_CallStaticJava()->_name;
2137 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity");
2138 }
2139 #endif
2140 // Non-escaped allocation returned from Java or runtime call have unknown values in fields.
2141 int new_edges = 0;
2142 for (EdgeIterator i(pta); i.has_next(); i.next()) {
2143 PointsToNode* field = i.get();
2144 if (field->is_Field() && field->as_Field()->is_oop()) {
2145 if (add_edge(field, phantom_obj)) {
2146 // New edge was added
2147 new_edges++;
2148 add_field_uses_to_worklist(field->as_Field());
2149 }
2150 }
2151 }
2152 return new_edges;
2153 }
2154
2155 // Find fields initializing values for allocations.
2156 int ConnectionGraph::find_init_values_null(JavaObjectNode* pta, PhaseValues* phase) {
2157 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
2158 Node* alloc = pta->ideal_node();
2159 // Do nothing for Call nodes since its fields values are unknown.
2160 if (!alloc->is_Allocate()) {
2161 return 0;
2162 }
2163 InitializeNode* ini = alloc->as_Allocate()->initialization();
2164 bool visited_bottom_offset = false;
2165 GrowableArray<int> offsets_worklist;
2166 int new_edges = 0;
2167
2168 // Check if an oop field's initializing value is recorded and add
2169 // a corresponding null if field's value if it is not recorded.
2170 // Connection Graph does not record a default initialization by null
2171 // captured by Initialize node.
2172 //
2173 for (EdgeIterator i(pta); i.has_next(); i.next()) {
2174 PointsToNode* field = i.get(); // Field (AddP)
2175 if (!field->is_Field() || !field->as_Field()->is_oop()) {
2176 continue; // Not oop field
2177 }
2178 int offset = field->as_Field()->offset();
2179 if (offset == Type::OffsetBot) {
2180 if (!visited_bottom_offset) {
2181 // OffsetBot is used to reference array's element,
2182 // always add reference to null to all Field nodes since we don't
2183 // known which element is referenced.
2184 if (add_edge(field, null_obj)) {
2185 // New edge was added
2186 new_edges++;
2187 add_field_uses_to_worklist(field->as_Field());
2188 visited_bottom_offset = true;
2189 }
2190 }
2191 } else {
2192 // Check only oop fields.
2193 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type();
2194 if (adr_type->isa_rawptr()) {
2195 #ifdef ASSERT
2196 // Raw pointers are used for initializing stores so skip it
2197 // since it should be recorded already
2198 Node* base = get_addp_base(field->ideal_node());
2199 assert(adr_type->isa_rawptr() && is_captured_store_address(field->ideal_node()), "unexpected pointer type");
2200 #endif
2201 continue;
2202 }
2203 if (!offsets_worklist.contains(offset)) {
2204 offsets_worklist.append(offset);
2205 Node* value = nullptr;
2206 if (ini != nullptr) {
2207 // StoreP::memory_type() == T_ADDRESS
2208 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS;
2209 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase);
2210 // Make sure initializing store has the same type as this AddP.
2211 // This AddP may reference non existing field because it is on a
2212 // dead branch of bimorphic call which is not eliminated yet.
2213 if (store != nullptr && store->is_Store() &&
2214 store->as_Store()->memory_type() == ft) {
2215 value = store->in(MemNode::ValueIn);
2216 #ifdef ASSERT
2217 if (VerifyConnectionGraph) {
2218 // Verify that AddP already points to all objects the value points to.
2219 PointsToNode* val = ptnode_adr(value->_idx);
2220 assert((val != nullptr), "should be processed already");
2221 PointsToNode* missed_obj = nullptr;
2222 if (val->is_JavaObject()) {
2223 if (!field->points_to(val->as_JavaObject())) {
2224 missed_obj = val;
2225 }
2226 } else {
2227 if (!val->is_LocalVar() || (val->edge_count() == 0)) {
2228 tty->print_cr("----------init store has invalid value -----");
2229 store->dump();
2230 val->dump();
2231 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already");
2232 }
2233 for (EdgeIterator j(val); j.has_next(); j.next()) {
2234 PointsToNode* obj = j.get();
2235 if (obj->is_JavaObject()) {
2236 if (!field->points_to(obj->as_JavaObject())) {
2237 missed_obj = obj;
2238 break;
2239 }
2240 }
2241 }
2242 }
2243 if (missed_obj != nullptr) {
2244 tty->print_cr("----------field---------------------------------");
2245 field->dump();
2246 tty->print_cr("----------missed referernce to object-----------");
2247 missed_obj->dump();
2248 tty->print_cr("----------object referernced by init store -----");
2249 store->dump();
2250 val->dump();
2251 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference");
2252 }
2253 }
2254 #endif
2255 } else {
2256 // There could be initializing stores which follow allocation.
2257 // For example, a volatile field store is not collected
2258 // by Initialize node.
2259 //
2260 // Need to check for dependent loads to separate such stores from
2261 // stores which follow loads. For now, add initial value null so
2262 // that compare pointers optimization works correctly.
2263 }
2264 }
2265 if (value == nullptr) {
2266 // A field's initializing value was not recorded. Add null.
2267 if (add_edge(field, null_obj)) {
2268 // New edge was added
2269 new_edges++;
2270 add_field_uses_to_worklist(field->as_Field());
2271 }
2272 }
2273 }
2274 }
2275 }
2276 return new_edges;
2277 }
2278
2279 // Adjust scalar_replaceable state after Connection Graph is built.
2280 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj, Unique_Node_List &reducible_merges) {
2281 // A Phi 'x' is a _candidate_ to be reducible if 'can_reduce_phi(x)'
2282 // returns true. If one of the constraints in this method set 'jobj' to NSR
2283 // then the candidate Phi is discarded. If the Phi has another SR 'jobj' as
2284 // input, 'adjust_scalar_replaceable_state' will eventually be called with
2285 // that other object and the Phi will become a reducible Phi.
2286 // There could be multiple merges involving the same jobj.
2287 Unique_Node_List candidates;
2288
2289 // Search for non-escaping objects which are not scalar replaceable
2290 // and mark them to propagate the state to referenced objects.
2291
2292 for (UseIterator i(jobj); i.has_next(); i.next()) {
2293 PointsToNode* use = i.get();
2294 if (use->is_Arraycopy()) {
2295 continue;
2296 }
2297 if (use->is_Field()) {
2298 FieldNode* field = use->as_Field();
2299 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
2300 // 1. An object is not scalar replaceable if the field into which it is
2301 // stored has unknown offset (stored into unknown element of an array).
2302 if (field->offset() == Type::OffsetBot) {
2303 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored at unknown offset"));
2304 return;
2305 }
2306 for (BaseIterator i(field); i.has_next(); i.next()) {
2307 PointsToNode* base = i.get();
2308 // 2. An object is not scalar replaceable if the field into which it is
2309 // stored has multiple bases one of which is null.
2310 if ((base == null_obj) && (field->base_count() > 1)) {
2311 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with potentially null base"));
2312 return;
2313 }
2314 // 2.5. An object is not scalar replaceable if the field into which it is
2315 // stored has NSR base.
2316 if (!base->scalar_replaceable()) {
2317 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with NSR base"));
2318 return;
2319 }
2320 }
2321 }
2322 assert(use->is_Field() || use->is_LocalVar(), "sanity");
2323 // 3. An object is not scalar replaceable if it is merged with other objects
2324 // and we can't remove the merge
2325 for (EdgeIterator j(use); j.has_next(); j.next()) {
2326 PointsToNode* ptn = j.get();
2327 if (ptn->is_JavaObject() && ptn != jobj) {
2328 Node* use_n = use->ideal_node();
2329
2330 // If it's already a candidate or confirmed reducible merge we can skip verification
2331 if (candidates.member(use_n)) {
2332 continue;
2333 } else if (reducible_merges.member(use_n)) {
2334 candidates.push(use_n);
2335 continue;
2336 }
2337
2338 if (use_n->is_Phi() && can_reduce_phi(use_n->as_Phi())) {
2339 candidates.push(use_n);
2340 } else {
2341 // Mark all objects as NSR if we can't remove the merge
2342 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA trace_merged_message(ptn)));
2343 set_not_scalar_replaceable(ptn NOT_PRODUCT(COMMA trace_merged_message(jobj)));
2344 }
2345 }
2346 }
2347 if (!jobj->scalar_replaceable()) {
2348 return;
2349 }
2350 }
2351
2352 for (EdgeIterator j(jobj); j.has_next(); j.next()) {
2353 if (j.get()->is_Arraycopy()) {
2354 continue;
2355 }
2356
2357 // Non-escaping object node should point only to field nodes.
2358 FieldNode* field = j.get()->as_Field();
2359 int offset = field->as_Field()->offset();
2360
2361 // 4. An object is not scalar replaceable if it has a field with unknown
2362 // offset (array's element is accessed in loop).
2363 if (offset == Type::OffsetBot) {
2364 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "has field with unknown offset"));
2365 return;
2366 }
2367 // 5. Currently an object is not scalar replaceable if a LoadStore node
2368 // access its field since the field value is unknown after it.
2369 //
2370 Node* n = field->ideal_node();
2371
2372 // Test for an unsafe access that was parsed as maybe off heap
2373 // (with a CheckCastPP to raw memory).
2374 assert(n->is_AddP(), "expect an address computation");
2375 if (n->in(AddPNode::Base)->is_top() &&
2376 n->in(AddPNode::Address)->Opcode() == Op_CheckCastPP) {
2377 assert(n->in(AddPNode::Address)->bottom_type()->isa_rawptr(), "raw address so raw cast expected");
2378 assert(_igvn->type(n->in(AddPNode::Address)->in(1))->isa_oopptr(), "cast pattern at unsafe access expected");
2379 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is used as base of mixed unsafe access"));
2380 return;
2381 }
2382
2383 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2384 Node* u = n->fast_out(i);
2385 if (u->is_LoadStore() || (u->is_Mem() && u->as_Mem()->is_mismatched_access())) {
2386 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is used in LoadStore or mismatched access"));
2387 return;
2388 }
2389 }
2390
2391 // 6. Or the address may point to more then one object. This may produce
2392 // the false positive result (set not scalar replaceable)
2393 // since the flow-insensitive escape analysis can't separate
2394 // the case when stores overwrite the field's value from the case
2395 // when stores happened on different control branches.
2396 //
2397 // Note: it will disable scalar replacement in some cases:
2398 //
2399 // Point p[] = new Point[1];
2400 // p[0] = new Point(); // Will be not scalar replaced
2401 //
2402 // but it will save us from incorrect optimizations in next cases:
2403 //
2404 // Point p[] = new Point[1];
2405 // if ( x ) p[0] = new Point(); // Will be not scalar replaced
2406 //
2407 if (field->base_count() > 1 && candidates.size() == 0) {
2408 for (BaseIterator i(field); i.has_next(); i.next()) {
2409 PointsToNode* base = i.get();
2410 // Don't take into account LocalVar nodes which
2411 // may point to only one object which should be also
2412 // this field's base by now.
2413 if (base->is_JavaObject() && base != jobj) {
2414 // Mark all bases.
2415 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "may point to more than one object"));
2416 set_not_scalar_replaceable(base NOT_PRODUCT(COMMA "may point to more than one object"));
2417 }
2418 }
2419
2420 if (!jobj->scalar_replaceable()) {
2421 return;
2422 }
2423 }
2424 }
2425
2426 // The candidate is truly a reducible merge only if none of the other
2427 // constraints ruled it as NSR. There could be multiple merges involving the
2428 // same jobj.
2429 assert(jobj->scalar_replaceable(), "sanity");
2430 for (uint i = 0; i < candidates.size(); i++ ) {
2431 Node* candidate = candidates.at(i);
2432 reducible_merges.push(candidate);
2433 }
2434 }
2435
2436 // Propagate NSR (Not scalar replaceable) state.
2437 void ConnectionGraph::find_scalar_replaceable_allocs(GrowableArray<JavaObjectNode*>& jobj_worklist) {
2438 int jobj_length = jobj_worklist.length();
2439 bool found_nsr_alloc = true;
2440 while (found_nsr_alloc) {
2441 found_nsr_alloc = false;
2442 for (int next = 0; next < jobj_length; ++next) {
2443 JavaObjectNode* jobj = jobj_worklist.at(next);
2444 for (UseIterator i(jobj); (jobj->scalar_replaceable() && i.has_next()); i.next()) {
2445 PointsToNode* use = i.get();
2446 if (use->is_Field()) {
2447 FieldNode* field = use->as_Field();
2448 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
2449 assert(field->offset() != Type::OffsetBot, "sanity");
2450 for (BaseIterator i(field); i.has_next(); i.next()) {
2451 PointsToNode* base = i.get();
2452 // An object is not scalar replaceable if the field into which
2453 // it is stored has NSR base.
2454 if ((base != null_obj) && !base->scalar_replaceable()) {
2455 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with NSR base"));
2456 found_nsr_alloc = true;
2457 break;
2458 }
2459 }
2460 }
2461 }
2462 }
2463 }
2464 }
2465
2466 #ifdef ASSERT
2467 void ConnectionGraph::verify_connection_graph(
2468 GrowableArray<PointsToNode*>& ptnodes_worklist,
2469 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist,
2470 GrowableArray<JavaObjectNode*>& java_objects_worklist,
2471 GrowableArray<Node*>& addp_worklist) {
2472 // Verify that graph is complete - no new edges could be added.
2473 int java_objects_length = java_objects_worklist.length();
2474 int non_escaped_length = non_escaped_allocs_worklist.length();
2475 int new_edges = 0;
2476 for (int next = 0; next < java_objects_length; ++next) {
2477 JavaObjectNode* ptn = java_objects_worklist.at(next);
2478 new_edges += add_java_object_edges(ptn, true);
2479 }
2480 assert(new_edges == 0, "graph was not complete");
2481 // Verify that escape state is final.
2482 int length = non_escaped_allocs_worklist.length();
2483 find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist);
2484 assert((non_escaped_length == non_escaped_allocs_worklist.length()) &&
2485 (non_escaped_length == length) &&
2486 (_worklist.length() == 0), "escape state was not final");
2487
2488 // Verify fields information.
2489 int addp_length = addp_worklist.length();
2490 for (int next = 0; next < addp_length; ++next ) {
2491 Node* n = addp_worklist.at(next);
2492 FieldNode* field = ptnode_adr(n->_idx)->as_Field();
2493 if (field->is_oop()) {
2494 // Verify that field has all bases
2495 Node* base = get_addp_base(n);
2496 PointsToNode* ptn = ptnode_adr(base->_idx);
2497 if (ptn->is_JavaObject()) {
2498 assert(field->has_base(ptn->as_JavaObject()), "sanity");
2499 } else {
2500 assert(ptn->is_LocalVar(), "sanity");
2501 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2502 PointsToNode* e = i.get();
2503 if (e->is_JavaObject()) {
2504 assert(field->has_base(e->as_JavaObject()), "sanity");
2505 }
2506 }
2507 }
2508 // Verify that all fields have initializing values.
2509 if (field->edge_count() == 0) {
2510 tty->print_cr("----------field does not have references----------");
2511 field->dump();
2512 for (BaseIterator i(field); i.has_next(); i.next()) {
2513 PointsToNode* base = i.get();
2514 tty->print_cr("----------field has next base---------------------");
2515 base->dump();
2516 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) {
2517 tty->print_cr("----------base has fields-------------------------");
2518 for (EdgeIterator j(base); j.has_next(); j.next()) {
2519 j.get()->dump();
2520 }
2521 tty->print_cr("----------base has references---------------------");
2522 for (UseIterator j(base); j.has_next(); j.next()) {
2523 j.get()->dump();
2524 }
2525 }
2526 }
2527 for (UseIterator i(field); i.has_next(); i.next()) {
2528 i.get()->dump();
2529 }
2530 assert(field->edge_count() > 0, "sanity");
2531 }
2532 }
2533 }
2534 }
2535 #endif
2536
2537 // Optimize ideal graph.
2538 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist,
2539 GrowableArray<MemBarStoreStoreNode*>& storestore_worklist) {
2540 Compile* C = _compile;
2541 PhaseIterGVN* igvn = _igvn;
2542 if (EliminateLocks) {
2543 // Mark locks before changing ideal graph.
2544 int cnt = C->macro_count();
2545 for (int i = 0; i < cnt; i++) {
2546 Node *n = C->macro_node(i);
2547 if (n->is_AbstractLock()) { // Lock and Unlock nodes
2548 AbstractLockNode* alock = n->as_AbstractLock();
2549 if (!alock->is_non_esc_obj()) {
2550 if (not_global_escape(alock->obj_node())) {
2551 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity");
2552 // The lock could be marked eliminated by lock coarsening
2553 // code during first IGVN before EA. Replace coarsened flag
2554 // to eliminate all associated locks/unlocks.
2555 #ifdef ASSERT
2556 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3");
2557 #endif
2558 alock->set_non_esc_obj();
2559 }
2560 }
2561 }
2562 }
2563 }
2564
2565 if (OptimizePtrCompare) {
2566 for (int i = 0; i < ptr_cmp_worklist.length(); i++) {
2567 Node *n = ptr_cmp_worklist.at(i);
2568 const TypeInt* tcmp = optimize_ptr_compare(n);
2569 if (tcmp->singleton()) {
2570 Node* cmp = igvn->makecon(tcmp);
2571 #ifndef PRODUCT
2572 if (PrintOptimizePtrCompare) {
2573 tty->print_cr("++++ Replaced: %d %s(%d,%d) --> %s", n->_idx, (n->Opcode() == Op_CmpP ? "CmpP" : "CmpN"), n->in(1)->_idx, n->in(2)->_idx, (tcmp == TypeInt::CC_EQ ? "EQ" : "NotEQ"));
2574 if (Verbose) {
2575 n->dump(1);
2576 }
2577 }
2578 #endif
2579 igvn->replace_node(n, cmp);
2580 }
2581 }
2582 }
2583
2584 // For MemBarStoreStore nodes added in library_call.cpp, check
2585 // escape status of associated AllocateNode and optimize out
2586 // MemBarStoreStore node if the allocated object never escapes.
2587 for (int i = 0; i < storestore_worklist.length(); i++) {
2588 Node* storestore = storestore_worklist.at(i);
2589 Node* alloc = storestore->in(MemBarNode::Precedent)->in(0);
2590 if (alloc->is_Allocate() && not_global_escape(alloc)) {
2591 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot);
2592 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory));
2593 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control));
2594 igvn->register_new_node_with_optimizer(mb);
2595 igvn->replace_node(storestore, mb);
2596 }
2597 }
2598 }
2599
2600 // Optimize objects compare.
2601 const TypeInt* ConnectionGraph::optimize_ptr_compare(Node* n) {
2602 assert(OptimizePtrCompare, "sanity");
2603 assert(n->Opcode() == Op_CmpN || n->Opcode() == Op_CmpP, "must be");
2604 const TypeInt* EQ = TypeInt::CC_EQ; // [0] == ZERO
2605 const TypeInt* NE = TypeInt::CC_GT; // [1] == ONE
2606 const TypeInt* UNKNOWN = TypeInt::CC; // [-1, 0,1]
2607
2608 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx);
2609 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx);
2610 JavaObjectNode* jobj1 = unique_java_object(n->in(1));
2611 JavaObjectNode* jobj2 = unique_java_object(n->in(2));
2612 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity");
2613 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity");
2614
2615 // Check simple cases first.
2616 if (jobj1 != nullptr) {
2617 if (jobj1->escape_state() == PointsToNode::NoEscape) {
2618 if (jobj1 == jobj2) {
2619 // Comparing the same not escaping object.
2620 return EQ;
2621 }
2622 Node* obj = jobj1->ideal_node();
2623 // Comparing not escaping allocation.
2624 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
2625 !ptn2->points_to(jobj1)) {
2626 return NE; // This includes nullness check.
2627 }
2628 }
2629 }
2630 if (jobj2 != nullptr) {
2631 if (jobj2->escape_state() == PointsToNode::NoEscape) {
2632 Node* obj = jobj2->ideal_node();
2633 // Comparing not escaping allocation.
2634 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
2635 !ptn1->points_to(jobj2)) {
2636 return NE; // This includes nullness check.
2637 }
2638 }
2639 }
2640 if (jobj1 != nullptr && jobj1 != phantom_obj &&
2641 jobj2 != nullptr && jobj2 != phantom_obj &&
2642 jobj1->ideal_node()->is_Con() &&
2643 jobj2->ideal_node()->is_Con()) {
2644 // Klass or String constants compare. Need to be careful with
2645 // compressed pointers - compare types of ConN and ConP instead of nodes.
2646 const Type* t1 = jobj1->ideal_node()->get_ptr_type();
2647 const Type* t2 = jobj2->ideal_node()->get_ptr_type();
2648 if (t1->make_ptr() == t2->make_ptr()) {
2649 return EQ;
2650 } else {
2651 return NE;
2652 }
2653 }
2654 if (ptn1->meet(ptn2)) {
2655 return UNKNOWN; // Sets are not disjoint
2656 }
2657
2658 // Sets are disjoint.
2659 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj);
2660 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj);
2661 bool set1_has_null_ptr = ptn1->points_to(null_obj);
2662 bool set2_has_null_ptr = ptn2->points_to(null_obj);
2663 if ((set1_has_unknown_ptr && set2_has_null_ptr) ||
2664 (set2_has_unknown_ptr && set1_has_null_ptr)) {
2665 // Check nullness of unknown object.
2666 return UNKNOWN;
2667 }
2668
2669 // Disjointness by itself is not sufficient since
2670 // alias analysis is not complete for escaped objects.
2671 // Disjoint sets are definitely unrelated only when
2672 // at least one set has only not escaping allocations.
2673 if (!set1_has_unknown_ptr && !set1_has_null_ptr) {
2674 if (ptn1->non_escaping_allocation()) {
2675 return NE;
2676 }
2677 }
2678 if (!set2_has_unknown_ptr && !set2_has_null_ptr) {
2679 if (ptn2->non_escaping_allocation()) {
2680 return NE;
2681 }
2682 }
2683 return UNKNOWN;
2684 }
2685
2686 // Connection Graph construction functions.
2687
2688 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) {
2689 PointsToNode* ptadr = _nodes.at(n->_idx);
2690 if (ptadr != nullptr) {
2691 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity");
2692 return;
2693 }
2694 Compile* C = _compile;
2695 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es);
2696 map_ideal_node(n, ptadr);
2697 }
2698
2699 PointsToNode* ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) {
2700 PointsToNode* ptadr = _nodes.at(n->_idx);
2701 if (ptadr != nullptr) {
2702 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity");
2703 return ptadr;
2704 }
2705 Compile* C = _compile;
2706 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es);
2707 map_ideal_node(n, ptadr);
2708 return ptadr;
2709 }
2710
2711 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) {
2712 PointsToNode* ptadr = _nodes.at(n->_idx);
2713 if (ptadr != nullptr) {
2714 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity");
2715 return;
2716 }
2717 bool unsafe = false;
2718 bool is_oop = is_oop_field(n, offset, &unsafe);
2719 if (unsafe) {
2720 es = PointsToNode::GlobalEscape;
2721 }
2722 Compile* C = _compile;
2723 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop);
2724 map_ideal_node(n, field);
2725 }
2726
2727 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es,
2728 PointsToNode* src, PointsToNode* dst) {
2729 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar");
2730 assert((src != null_obj) && (dst != null_obj), "not for ConP null");
2731 PointsToNode* ptadr = _nodes.at(n->_idx);
2732 if (ptadr != nullptr) {
2733 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity");
2734 return;
2735 }
2736 Compile* C = _compile;
2737 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es);
2738 map_ideal_node(n, ptadr);
2739 // Add edge from arraycopy node to source object.
2740 (void)add_edge(ptadr, src);
2741 src->set_arraycopy_src();
2742 // Add edge from destination object to arraycopy node.
2743 (void)add_edge(dst, ptadr);
2744 dst->set_arraycopy_dst();
2745 }
2746
2747 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) {
2748 const Type* adr_type = n->as_AddP()->bottom_type();
2749 BasicType bt = T_INT;
2750 if (offset == Type::OffsetBot) {
2751 // Check only oop fields.
2752 if (!adr_type->isa_aryptr() ||
2753 adr_type->isa_aryptr()->elem() == Type::BOTTOM ||
2754 adr_type->isa_aryptr()->elem()->make_oopptr() != nullptr) {
2755 // OffsetBot is used to reference array's element. Ignore first AddP.
2756 if (find_second_addp(n, n->in(AddPNode::Base)) == nullptr) {
2757 bt = T_OBJECT;
2758 }
2759 }
2760 } else if (offset != oopDesc::klass_offset_in_bytes()) {
2761 if (adr_type->isa_instptr()) {
2762 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field();
2763 if (field != nullptr) {
2764 bt = field->layout_type();
2765 } else {
2766 // Check for unsafe oop field access
2767 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2768 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2769 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN) ||
2770 BarrierSet::barrier_set()->barrier_set_c2()->escape_has_out_with_unsafe_object(n)) {
2771 bt = T_OBJECT;
2772 (*unsafe) = true;
2773 }
2774 }
2775 } else if (adr_type->isa_aryptr()) {
2776 if (offset == arrayOopDesc::length_offset_in_bytes()) {
2777 // Ignore array length load.
2778 } else if (find_second_addp(n, n->in(AddPNode::Base)) != nullptr) {
2779 // Ignore first AddP.
2780 } else {
2781 const Type* elemtype = adr_type->isa_aryptr()->elem();
2782 bt = elemtype->array_element_basic_type();
2783 }
2784 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) {
2785 // Allocation initialization, ThreadLocal field access, unsafe access
2786 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2787 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2788 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN) ||
2789 BarrierSet::barrier_set()->barrier_set_c2()->escape_has_out_with_unsafe_object(n)) {
2790 bt = T_OBJECT;
2791 }
2792 }
2793 }
2794 // Note: T_NARROWOOP is not classed as a real reference type
2795 return (is_reference_type(bt) || bt == T_NARROWOOP);
2796 }
2797
2798 // Returns unique pointed java object or null.
2799 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) const {
2800 // If the node was created after the escape computation we can't answer.
2801 uint idx = n->_idx;
2802 if (idx >= nodes_size()) {
2803 return nullptr;
2804 }
2805 PointsToNode* ptn = ptnode_adr(idx);
2806 if (ptn == nullptr) {
2807 return nullptr;
2808 }
2809 if (ptn->is_JavaObject()) {
2810 return ptn->as_JavaObject();
2811 }
2812 assert(ptn->is_LocalVar(), "sanity");
2813 // Check all java objects it points to.
2814 JavaObjectNode* jobj = nullptr;
2815 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2816 PointsToNode* e = i.get();
2817 if (e->is_JavaObject()) {
2818 if (jobj == nullptr) {
2819 jobj = e->as_JavaObject();
2820 } else if (jobj != e) {
2821 return nullptr;
2822 }
2823 }
2824 }
2825 return jobj;
2826 }
2827
2828 // Return true if this node points only to non-escaping allocations.
2829 bool PointsToNode::non_escaping_allocation() {
2830 if (is_JavaObject()) {
2831 Node* n = ideal_node();
2832 if (n->is_Allocate() || n->is_CallStaticJava()) {
2833 return (escape_state() == PointsToNode::NoEscape);
2834 } else {
2835 return false;
2836 }
2837 }
2838 assert(is_LocalVar(), "sanity");
2839 // Check all java objects it points to.
2840 for (EdgeIterator i(this); i.has_next(); i.next()) {
2841 PointsToNode* e = i.get();
2842 if (e->is_JavaObject()) {
2843 Node* n = e->ideal_node();
2844 if ((e->escape_state() != PointsToNode::NoEscape) ||
2845 !(n->is_Allocate() || n->is_CallStaticJava())) {
2846 return false;
2847 }
2848 }
2849 }
2850 return true;
2851 }
2852
2853 // Return true if we know the node does not escape globally.
2854 bool ConnectionGraph::not_global_escape(Node *n) {
2855 assert(!_collecting, "should not call during graph construction");
2856 // If the node was created after the escape computation we can't answer.
2857 uint idx = n->_idx;
2858 if (idx >= nodes_size()) {
2859 return false;
2860 }
2861 PointsToNode* ptn = ptnode_adr(idx);
2862 if (ptn == nullptr) {
2863 return false; // not in congraph (e.g. ConI)
2864 }
2865 PointsToNode::EscapeState es = ptn->escape_state();
2866 // If we have already computed a value, return it.
2867 if (es >= PointsToNode::GlobalEscape) {
2868 return false;
2869 }
2870 if (ptn->is_JavaObject()) {
2871 return true; // (es < PointsToNode::GlobalEscape);
2872 }
2873 assert(ptn->is_LocalVar(), "sanity");
2874 // Check all java objects it points to.
2875 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2876 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) {
2877 return false;
2878 }
2879 }
2880 return true;
2881 }
2882
2883
2884 // Helper functions
2885
2886 // Return true if this node points to specified node or nodes it points to.
2887 bool PointsToNode::points_to(JavaObjectNode* ptn) const {
2888 if (is_JavaObject()) {
2889 return (this == ptn);
2890 }
2891 assert(is_LocalVar() || is_Field(), "sanity");
2892 for (EdgeIterator i(this); i.has_next(); i.next()) {
2893 if (i.get() == ptn) {
2894 return true;
2895 }
2896 }
2897 return false;
2898 }
2899
2900 // Return true if one node points to an other.
2901 bool PointsToNode::meet(PointsToNode* ptn) {
2902 if (this == ptn) {
2903 return true;
2904 } else if (ptn->is_JavaObject()) {
2905 return this->points_to(ptn->as_JavaObject());
2906 } else if (this->is_JavaObject()) {
2907 return ptn->points_to(this->as_JavaObject());
2908 }
2909 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity");
2910 int ptn_count = ptn->edge_count();
2911 for (EdgeIterator i(this); i.has_next(); i.next()) {
2912 PointsToNode* this_e = i.get();
2913 for (int j = 0; j < ptn_count; j++) {
2914 if (this_e == ptn->edge(j)) {
2915 return true;
2916 }
2917 }
2918 }
2919 return false;
2920 }
2921
2922 #ifdef ASSERT
2923 // Return true if bases point to this java object.
2924 bool FieldNode::has_base(JavaObjectNode* jobj) const {
2925 for (BaseIterator i(this); i.has_next(); i.next()) {
2926 if (i.get() == jobj) {
2927 return true;
2928 }
2929 }
2930 return false;
2931 }
2932 #endif
2933
2934 bool ConnectionGraph::is_captured_store_address(Node* addp) {
2935 // Handle simple case first.
2936 assert(_igvn->type(addp)->isa_oopptr() == nullptr, "should be raw access");
2937 if (addp->in(AddPNode::Address)->is_Proj() && addp->in(AddPNode::Address)->in(0)->is_Allocate()) {
2938 return true;
2939 } else if (addp->in(AddPNode::Address)->is_Phi()) {
2940 for (DUIterator_Fast imax, i = addp->fast_outs(imax); i < imax; i++) {
2941 Node* addp_use = addp->fast_out(i);
2942 if (addp_use->is_Store()) {
2943 for (DUIterator_Fast jmax, j = addp_use->fast_outs(jmax); j < jmax; j++) {
2944 if (addp_use->fast_out(j)->is_Initialize()) {
2945 return true;
2946 }
2947 }
2948 }
2949 }
2950 }
2951 return false;
2952 }
2953
2954 int ConnectionGraph::address_offset(Node* adr, PhaseValues* phase) {
2955 const Type *adr_type = phase->type(adr);
2956 if (adr->is_AddP() && adr_type->isa_oopptr() == nullptr && is_captured_store_address(adr)) {
2957 // We are computing a raw address for a store captured by an Initialize
2958 // compute an appropriate address type. AddP cases #3 and #5 (see below).
2959 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
2960 assert(offs != Type::OffsetBot ||
2961 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
2962 "offset must be a constant or it is initialization of array");
2963 return offs;
2964 }
2965 const TypePtr *t_ptr = adr_type->isa_ptr();
2966 assert(t_ptr != nullptr, "must be a pointer type");
2967 return t_ptr->offset();
2968 }
2969
2970 Node* ConnectionGraph::get_addp_base(Node *addp) {
2971 assert(addp->is_AddP(), "must be AddP");
2972 //
2973 // AddP cases for Base and Address inputs:
2974 // case #1. Direct object's field reference:
2975 // Allocate
2976 // |
2977 // Proj #5 ( oop result )
2978 // |
2979 // CheckCastPP (cast to instance type)
2980 // | |
2981 // AddP ( base == address )
2982 //
2983 // case #2. Indirect object's field reference:
2984 // Phi
2985 // |
2986 // CastPP (cast to instance type)
2987 // | |
2988 // AddP ( base == address )
2989 //
2990 // case #3. Raw object's field reference for Initialize node:
2991 // Allocate
2992 // |
2993 // Proj #5 ( oop result )
2994 // top |
2995 // \ |
2996 // AddP ( base == top )
2997 //
2998 // case #4. Array's element reference:
2999 // {CheckCastPP | CastPP}
3000 // | | |
3001 // | AddP ( array's element offset )
3002 // | |
3003 // AddP ( array's offset )
3004 //
3005 // case #5. Raw object's field reference for arraycopy stub call:
3006 // The inline_native_clone() case when the arraycopy stub is called
3007 // after the allocation before Initialize and CheckCastPP nodes.
3008 // Allocate
3009 // |
3010 // Proj #5 ( oop result )
3011 // | |
3012 // AddP ( base == address )
3013 //
3014 // case #6. Constant Pool, ThreadLocal, CastX2P or
3015 // Raw object's field reference:
3016 // {ConP, ThreadLocal, CastX2P, raw Load}
3017 // top |
3018 // \ |
3019 // AddP ( base == top )
3020 //
3021 // case #7. Klass's field reference.
3022 // LoadKlass
3023 // | |
3024 // AddP ( base == address )
3025 //
3026 // case #8. narrow Klass's field reference.
3027 // LoadNKlass
3028 // |
3029 // DecodeN
3030 // | |
3031 // AddP ( base == address )
3032 //
3033 // case #9. Mixed unsafe access
3034 // {instance}
3035 // |
3036 // CheckCastPP (raw)
3037 // top |
3038 // \ |
3039 // AddP ( base == top )
3040 //
3041 Node *base = addp->in(AddPNode::Base);
3042 if (base->uncast()->is_top()) { // The AddP case #3 and #6 and #9.
3043 base = addp->in(AddPNode::Address);
3044 while (base->is_AddP()) {
3045 // Case #6 (unsafe access) may have several chained AddP nodes.
3046 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only");
3047 base = base->in(AddPNode::Address);
3048 }
3049 if (base->Opcode() == Op_CheckCastPP &&
3050 base->bottom_type()->isa_rawptr() &&
3051 _igvn->type(base->in(1))->isa_oopptr()) {
3052 base = base->in(1); // Case #9
3053 } else {
3054 Node* uncast_base = base->uncast();
3055 int opcode = uncast_base->Opcode();
3056 assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
3057 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
3058 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != nullptr)) ||
3059 is_captured_store_address(addp), "sanity");
3060 }
3061 }
3062 return base;
3063 }
3064
3065 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) {
3066 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
3067 Node* addp2 = addp->raw_out(0);
3068 if (addp->outcnt() == 1 && addp2->is_AddP() &&
3069 addp2->in(AddPNode::Base) == n &&
3070 addp2->in(AddPNode::Address) == addp) {
3071 assert(addp->in(AddPNode::Base) == n, "expecting the same base");
3072 //
3073 // Find array's offset to push it on worklist first and
3074 // as result process an array's element offset first (pushed second)
3075 // to avoid CastPP for the array's offset.
3076 // Otherwise the inserted CastPP (LocalVar) will point to what
3077 // the AddP (Field) points to. Which would be wrong since
3078 // the algorithm expects the CastPP has the same point as
3079 // as AddP's base CheckCastPP (LocalVar).
3080 //
3081 // ArrayAllocation
3082 // |
3083 // CheckCastPP
3084 // |
3085 // memProj (from ArrayAllocation CheckCastPP)
3086 // | ||
3087 // | || Int (element index)
3088 // | || | ConI (log(element size))
3089 // | || | /
3090 // | || LShift
3091 // | || /
3092 // | AddP (array's element offset)
3093 // | |
3094 // | | ConI (array's offset: #12(32-bits) or #24(64-bits))
3095 // | / /
3096 // AddP (array's offset)
3097 // |
3098 // Load/Store (memory operation on array's element)
3099 //
3100 return addp2;
3101 }
3102 return nullptr;
3103 }
3104
3105 //
3106 // Adjust the type and inputs of an AddP which computes the
3107 // address of a field of an instance
3108 //
3109 bool ConnectionGraph::split_AddP(Node *addp, Node *base) {
3110 PhaseGVN* igvn = _igvn;
3111 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
3112 assert(base_t != nullptr && base_t->is_known_instance(), "expecting instance oopptr");
3113 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
3114 if (t == nullptr) {
3115 // We are computing a raw address for a store captured by an Initialize
3116 // compute an appropriate address type (cases #3 and #5).
3117 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
3118 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
3119 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
3120 assert(offs != Type::OffsetBot, "offset must be a constant");
3121 t = base_t->add_offset(offs)->is_oopptr();
3122 }
3123 int inst_id = base_t->instance_id();
3124 assert(!t->is_known_instance() || t->instance_id() == inst_id,
3125 "old type must be non-instance or match new type");
3126
3127 // The type 't' could be subclass of 'base_t'.
3128 // As result t->offset() could be large then base_t's size and it will
3129 // cause the failure in add_offset() with narrow oops since TypeOopPtr()
3130 // constructor verifies correctness of the offset.
3131 //
3132 // It could happened on subclass's branch (from the type profiling
3133 // inlining) which was not eliminated during parsing since the exactness
3134 // of the allocation type was not propagated to the subclass type check.
3135 //
3136 // Or the type 't' could be not related to 'base_t' at all.
3137 // It could happened when CHA type is different from MDO type on a dead path
3138 // (for example, from instanceof check) which is not collapsed during parsing.
3139 //
3140 // Do nothing for such AddP node and don't process its users since
3141 // this code branch will go away.
3142 //
3143 if (!t->is_known_instance() &&
3144 !base_t->maybe_java_subtype_of(t)) {
3145 return false; // bail out
3146 }
3147 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
3148 // Do NOT remove the next line: ensure a new alias index is allocated
3149 // for the instance type. Note: C++ will not remove it since the call
3150 // has side effect.
3151 int alias_idx = _compile->get_alias_index(tinst);
3152 igvn->set_type(addp, tinst);
3153 // record the allocation in the node map
3154 set_map(addp, get_map(base->_idx));
3155 // Set addp's Base and Address to 'base'.
3156 Node *abase = addp->in(AddPNode::Base);
3157 Node *adr = addp->in(AddPNode::Address);
3158 if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
3159 adr->in(0)->_idx == (uint)inst_id) {
3160 // Skip AddP cases #3 and #5.
3161 } else {
3162 assert(!abase->is_top(), "sanity"); // AddP case #3
3163 if (abase != base) {
3164 igvn->hash_delete(addp);
3165 addp->set_req(AddPNode::Base, base);
3166 if (abase == adr) {
3167 addp->set_req(AddPNode::Address, base);
3168 } else {
3169 // AddP case #4 (adr is array's element offset AddP node)
3170 #ifdef ASSERT
3171 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
3172 assert(adr->is_AddP() && atype != nullptr &&
3173 atype->instance_id() == inst_id, "array's element offset should be processed first");
3174 #endif
3175 }
3176 igvn->hash_insert(addp);
3177 }
3178 }
3179 // Put on IGVN worklist since at least addp's type was changed above.
3180 record_for_optimizer(addp);
3181 return true;
3182 }
3183
3184 //
3185 // Create a new version of orig_phi if necessary. Returns either the newly
3186 // created phi or an existing phi. Sets create_new to indicate whether a new
3187 // phi was created. Cache the last newly created phi in the node map.
3188 //
3189 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) {
3190 Compile *C = _compile;
3191 PhaseGVN* igvn = _igvn;
3192 new_created = false;
3193 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
3194 // nothing to do if orig_phi is bottom memory or matches alias_idx
3195 if (phi_alias_idx == alias_idx) {
3196 return orig_phi;
3197 }
3198 // Have we recently created a Phi for this alias index?
3199 PhiNode *result = get_map_phi(orig_phi->_idx);
3200 if (result != nullptr && C->get_alias_index(result->adr_type()) == alias_idx) {
3201 return result;
3202 }
3203 // Previous check may fail when the same wide memory Phi was split into Phis
3204 // for different memory slices. Search all Phis for this region.
3205 if (result != nullptr) {
3206 Node* region = orig_phi->in(0);
3207 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
3208 Node* phi = region->fast_out(i);
3209 if (phi->is_Phi() &&
3210 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
3211 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
3212 return phi->as_Phi();
3213 }
3214 }
3215 }
3216 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) {
3217 if (C->do_escape_analysis() == true && !C->failing()) {
3218 // Retry compilation without escape analysis.
3219 // If this is the first failure, the sentinel string will "stick"
3220 // to the Compile object, and the C2Compiler will see it and retry.
3221 C->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
3222 }
3223 return nullptr;
3224 }
3225 orig_phi_worklist.append_if_missing(orig_phi);
3226 const TypePtr *atype = C->get_adr_type(alias_idx);
3227 result = PhiNode::make(orig_phi->in(0), nullptr, Type::MEMORY, atype);
3228 C->copy_node_notes_to(result, orig_phi);
3229 igvn->set_type(result, result->bottom_type());
3230 record_for_optimizer(result);
3231 set_map(orig_phi, result);
3232 new_created = true;
3233 return result;
3234 }
3235
3236 //
3237 // Return a new version of Memory Phi "orig_phi" with the inputs having the
3238 // specified alias index.
3239 //
3240 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) {
3241 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
3242 Compile *C = _compile;
3243 PhaseGVN* igvn = _igvn;
3244 bool new_phi_created;
3245 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created);
3246 if (!new_phi_created) {
3247 return result;
3248 }
3249 GrowableArray<PhiNode *> phi_list;
3250 GrowableArray<uint> cur_input;
3251 PhiNode *phi = orig_phi;
3252 uint idx = 1;
3253 bool finished = false;
3254 while(!finished) {
3255 while (idx < phi->req()) {
3256 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist);
3257 if (mem != nullptr && mem->is_Phi()) {
3258 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created);
3259 if (new_phi_created) {
3260 // found an phi for which we created a new split, push current one on worklist and begin
3261 // processing new one
3262 phi_list.push(phi);
3263 cur_input.push(idx);
3264 phi = mem->as_Phi();
3265 result = newphi;
3266 idx = 1;
3267 continue;
3268 } else {
3269 mem = newphi;
3270 }
3271 }
3272 if (C->failing()) {
3273 return nullptr;
3274 }
3275 result->set_req(idx++, mem);
3276 }
3277 #ifdef ASSERT
3278 // verify that the new Phi has an input for each input of the original
3279 assert( phi->req() == result->req(), "must have same number of inputs.");
3280 assert( result->in(0) != nullptr && result->in(0) == phi->in(0), "regions must match");
3281 #endif
3282 // Check if all new phi's inputs have specified alias index.
3283 // Otherwise use old phi.
3284 for (uint i = 1; i < phi->req(); i++) {
3285 Node* in = result->in(i);
3286 assert((phi->in(i) == nullptr) == (in == nullptr), "inputs must correspond.");
3287 }
3288 // we have finished processing a Phi, see if there are any more to do
3289 finished = (phi_list.length() == 0 );
3290 if (!finished) {
3291 phi = phi_list.pop();
3292 idx = cur_input.pop();
3293 PhiNode *prev_result = get_map_phi(phi->_idx);
3294 prev_result->set_req(idx++, result);
3295 result = prev_result;
3296 }
3297 }
3298 return result;
3299 }
3300
3301 //
3302 // The next methods are derived from methods in MemNode.
3303 //
3304 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
3305 Node *mem = mmem;
3306 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
3307 // means an array I have not precisely typed yet. Do not do any
3308 // alias stuff with it any time soon.
3309 if (toop->base() != Type::AnyPtr &&
3310 !(toop->isa_instptr() &&
3311 toop->is_instptr()->instance_klass()->is_java_lang_Object() &&
3312 toop->offset() == Type::OffsetBot)) {
3313 mem = mmem->memory_at(alias_idx);
3314 // Update input if it is progress over what we have now
3315 }
3316 return mem;
3317 }
3318
3319 //
3320 // Move memory users to their memory slices.
3321 //
3322 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) {
3323 Compile* C = _compile;
3324 PhaseGVN* igvn = _igvn;
3325 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
3326 assert(tp != nullptr, "ptr type");
3327 int alias_idx = C->get_alias_index(tp);
3328 int general_idx = C->get_general_index(alias_idx);
3329
3330 // Move users first
3331 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3332 Node* use = n->fast_out(i);
3333 if (use->is_MergeMem()) {
3334 MergeMemNode* mmem = use->as_MergeMem();
3335 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
3336 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
3337 continue; // Nothing to do
3338 }
3339 // Replace previous general reference to mem node.
3340 uint orig_uniq = C->unique();
3341 Node* m = find_inst_mem(n, general_idx, orig_phis);
3342 assert(orig_uniq == C->unique(), "no new nodes");
3343 mmem->set_memory_at(general_idx, m);
3344 --imax;
3345 --i;
3346 } else if (use->is_MemBar()) {
3347 assert(!use->is_Initialize(), "initializing stores should not be moved");
3348 if (use->req() > MemBarNode::Precedent &&
3349 use->in(MemBarNode::Precedent) == n) {
3350 // Don't move related membars.
3351 record_for_optimizer(use);
3352 continue;
3353 }
3354 tp = use->as_MemBar()->adr_type()->isa_ptr();
3355 if ((tp != nullptr && C->get_alias_index(tp) == alias_idx) ||
3356 alias_idx == general_idx) {
3357 continue; // Nothing to do
3358 }
3359 // Move to general memory slice.
3360 uint orig_uniq = C->unique();
3361 Node* m = find_inst_mem(n, general_idx, orig_phis);
3362 assert(orig_uniq == C->unique(), "no new nodes");
3363 igvn->hash_delete(use);
3364 imax -= use->replace_edge(n, m, igvn);
3365 igvn->hash_insert(use);
3366 record_for_optimizer(use);
3367 --i;
3368 #ifdef ASSERT
3369 } else if (use->is_Mem()) {
3370 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) {
3371 // Don't move related cardmark.
3372 continue;
3373 }
3374 // Memory nodes should have new memory input.
3375 tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
3376 assert(tp != nullptr, "ptr type");
3377 int idx = C->get_alias_index(tp);
3378 assert(get_map(use->_idx) != nullptr || idx == alias_idx,
3379 "Following memory nodes should have new memory input or be on the same memory slice");
3380 } else if (use->is_Phi()) {
3381 // Phi nodes should be split and moved already.
3382 tp = use->as_Phi()->adr_type()->isa_ptr();
3383 assert(tp != nullptr, "ptr type");
3384 int idx = C->get_alias_index(tp);
3385 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
3386 } else {
3387 use->dump();
3388 assert(false, "should not be here");
3389 #endif
3390 }
3391 }
3392 }
3393
3394 //
3395 // Search memory chain of "mem" to find a MemNode whose address
3396 // is the specified alias index.
3397 //
3398 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) {
3399 if (orig_mem == nullptr) {
3400 return orig_mem;
3401 }
3402 Compile* C = _compile;
3403 PhaseGVN* igvn = _igvn;
3404 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
3405 bool is_instance = (toop != nullptr) && toop->is_known_instance();
3406 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
3407 Node *prev = nullptr;
3408 Node *result = orig_mem;
3409 while (prev != result) {
3410 prev = result;
3411 if (result == start_mem) {
3412 break; // hit one of our sentinels
3413 }
3414 if (result->is_Mem()) {
3415 const Type *at = igvn->type(result->in(MemNode::Address));
3416 if (at == Type::TOP) {
3417 break; // Dead
3418 }
3419 assert (at->isa_ptr() != nullptr, "pointer type required.");
3420 int idx = C->get_alias_index(at->is_ptr());
3421 if (idx == alias_idx) {
3422 break; // Found
3423 }
3424 if (!is_instance && (at->isa_oopptr() == nullptr ||
3425 !at->is_oopptr()->is_known_instance())) {
3426 break; // Do not skip store to general memory slice.
3427 }
3428 result = result->in(MemNode::Memory);
3429 }
3430 if (!is_instance) {
3431 continue; // don't search further for non-instance types
3432 }
3433 // skip over a call which does not affect this memory slice
3434 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
3435 Node *proj_in = result->in(0);
3436 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
3437 break; // hit one of our sentinels
3438 } else if (proj_in->is_Call()) {
3439 // ArrayCopy node processed here as well
3440 CallNode *call = proj_in->as_Call();
3441 if (!call->may_modify(toop, igvn)) {
3442 result = call->in(TypeFunc::Memory);
3443 }
3444 } else if (proj_in->is_Initialize()) {
3445 AllocateNode* alloc = proj_in->as_Initialize()->allocation();
3446 // Stop if this is the initialization for the object instance which
3447 // which contains this memory slice, otherwise skip over it.
3448 if (alloc == nullptr || alloc->_idx != (uint)toop->instance_id()) {
3449 result = proj_in->in(TypeFunc::Memory);
3450 }
3451 } else if (proj_in->is_MemBar()) {
3452 // Check if there is an array copy for a clone
3453 // Step over GC barrier when ReduceInitialCardMarks is disabled
3454 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
3455 Node* control_proj_ac = bs->step_over_gc_barrier(proj_in->in(0));
3456
3457 if (control_proj_ac->is_Proj() && control_proj_ac->in(0)->is_ArrayCopy()) {
3458 // Stop if it is a clone
3459 ArrayCopyNode* ac = control_proj_ac->in(0)->as_ArrayCopy();
3460 if (ac->may_modify(toop, igvn)) {
3461 break;
3462 }
3463 }
3464 result = proj_in->in(TypeFunc::Memory);
3465 }
3466 } else if (result->is_MergeMem()) {
3467 MergeMemNode *mmem = result->as_MergeMem();
3468 result = step_through_mergemem(mmem, alias_idx, toop);
3469 if (result == mmem->base_memory()) {
3470 // Didn't find instance memory, search through general slice recursively.
3471 result = mmem->memory_at(C->get_general_index(alias_idx));
3472 result = find_inst_mem(result, alias_idx, orig_phis);
3473 if (C->failing()) {
3474 return nullptr;
3475 }
3476 mmem->set_memory_at(alias_idx, result);
3477 }
3478 } else if (result->is_Phi() &&
3479 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
3480 Node *un = result->as_Phi()->unique_input(igvn);
3481 if (un != nullptr) {
3482 orig_phis.append_if_missing(result->as_Phi());
3483 result = un;
3484 } else {
3485 break;
3486 }
3487 } else if (result->is_ClearArray()) {
3488 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) {
3489 // Can not bypass initialization of the instance
3490 // we are looking for.
3491 break;
3492 }
3493 // Otherwise skip it (the call updated 'result' value).
3494 } else if (result->Opcode() == Op_SCMemProj) {
3495 Node* mem = result->in(0);
3496 Node* adr = nullptr;
3497 if (mem->is_LoadStore()) {
3498 adr = mem->in(MemNode::Address);
3499 } else {
3500 assert(mem->Opcode() == Op_EncodeISOArray ||
3501 mem->Opcode() == Op_StrCompressedCopy, "sanity");
3502 adr = mem->in(3); // Memory edge corresponds to destination array
3503 }
3504 const Type *at = igvn->type(adr);
3505 if (at != Type::TOP) {
3506 assert(at->isa_ptr() != nullptr, "pointer type required.");
3507 int idx = C->get_alias_index(at->is_ptr());
3508 if (idx == alias_idx) {
3509 // Assert in debug mode
3510 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
3511 break; // In product mode return SCMemProj node
3512 }
3513 }
3514 result = mem->in(MemNode::Memory);
3515 } else if (result->Opcode() == Op_StrInflatedCopy) {
3516 Node* adr = result->in(3); // Memory edge corresponds to destination array
3517 const Type *at = igvn->type(adr);
3518 if (at != Type::TOP) {
3519 assert(at->isa_ptr() != nullptr, "pointer type required.");
3520 int idx = C->get_alias_index(at->is_ptr());
3521 if (idx == alias_idx) {
3522 // Assert in debug mode
3523 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
3524 break; // In product mode return SCMemProj node
3525 }
3526 }
3527 result = result->in(MemNode::Memory);
3528 }
3529 }
3530 if (result->is_Phi()) {
3531 PhiNode *mphi = result->as_Phi();
3532 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
3533 const TypePtr *t = mphi->adr_type();
3534 if (!is_instance) {
3535 // Push all non-instance Phis on the orig_phis worklist to update inputs
3536 // during Phase 4 if needed.
3537 orig_phis.append_if_missing(mphi);
3538 } else if (C->get_alias_index(t) != alias_idx) {
3539 // Create a new Phi with the specified alias index type.
3540 result = split_memory_phi(mphi, alias_idx, orig_phis);
3541 }
3542 }
3543 // the result is either MemNode, PhiNode, InitializeNode.
3544 return result;
3545 }
3546
3547 //
3548 // Convert the types of non-escaped object to instance types where possible,
3549 // propagate the new type information through the graph, and update memory
3550 // edges and MergeMem inputs to reflect the new type.
3551 //
3552 // We start with allocations (and calls which may be allocations) on alloc_worklist.
3553 // The processing is done in 4 phases:
3554 //
3555 // Phase 1: Process possible allocations from alloc_worklist. Create instance
3556 // types for the CheckCastPP for allocations where possible.
3557 // Propagate the new types through users as follows:
3558 // casts and Phi: push users on alloc_worklist
3559 // AddP: cast Base and Address inputs to the instance type
3560 // push any AddP users on alloc_worklist and push any memnode
3561 // users onto memnode_worklist.
3562 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
3563 // search the Memory chain for a store with the appropriate type
3564 // address type. If a Phi is found, create a new version with
3565 // the appropriate memory slices from each of the Phi inputs.
3566 // For stores, process the users as follows:
3567 // MemNode: push on memnode_worklist
3568 // MergeMem: push on mergemem_worklist
3569 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
3570 // moving the first node encountered of each instance type to the
3571 // the input corresponding to its alias index.
3572 // appropriate memory slice.
3573 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
3574 //
3575 // In the following example, the CheckCastPP nodes are the cast of allocation
3576 // results and the allocation of node 29 is non-escaped and eligible to be an
3577 // instance type.
3578 //
3579 // We start with:
3580 //
3581 // 7 Parm #memory
3582 // 10 ConI "12"
3583 // 19 CheckCastPP "Foo"
3584 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
3585 // 29 CheckCastPP "Foo"
3586 // 30 AddP _ 29 29 10 Foo+12 alias_index=4
3587 //
3588 // 40 StoreP 25 7 20 ... alias_index=4
3589 // 50 StoreP 35 40 30 ... alias_index=4
3590 // 60 StoreP 45 50 20 ... alias_index=4
3591 // 70 LoadP _ 60 30 ... alias_index=4
3592 // 80 Phi 75 50 60 Memory alias_index=4
3593 // 90 LoadP _ 80 30 ... alias_index=4
3594 // 100 LoadP _ 80 20 ... alias_index=4
3595 //
3596 //
3597 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
3598 // and creating a new alias index for node 30. This gives:
3599 //
3600 // 7 Parm #memory
3601 // 10 ConI "12"
3602 // 19 CheckCastPP "Foo"
3603 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
3604 // 29 CheckCastPP "Foo" iid=24
3605 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
3606 //
3607 // 40 StoreP 25 7 20 ... alias_index=4
3608 // 50 StoreP 35 40 30 ... alias_index=6
3609 // 60 StoreP 45 50 20 ... alias_index=4
3610 // 70 LoadP _ 60 30 ... alias_index=6
3611 // 80 Phi 75 50 60 Memory alias_index=4
3612 // 90 LoadP _ 80 30 ... alias_index=6
3613 // 100 LoadP _ 80 20 ... alias_index=4
3614 //
3615 // In phase 2, new memory inputs are computed for the loads and stores,
3616 // And a new version of the phi is created. In phase 4, the inputs to
3617 // node 80 are updated and then the memory nodes are updated with the
3618 // values computed in phase 2. This results in:
3619 //
3620 // 7 Parm #memory
3621 // 10 ConI "12"
3622 // 19 CheckCastPP "Foo"
3623 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
3624 // 29 CheckCastPP "Foo" iid=24
3625 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
3626 //
3627 // 40 StoreP 25 7 20 ... alias_index=4
3628 // 50 StoreP 35 7 30 ... alias_index=6
3629 // 60 StoreP 45 40 20 ... alias_index=4
3630 // 70 LoadP _ 50 30 ... alias_index=6
3631 // 80 Phi 75 40 60 Memory alias_index=4
3632 // 120 Phi 75 50 50 Memory alias_index=6
3633 // 90 LoadP _ 120 30 ... alias_index=6
3634 // 100 LoadP _ 80 20 ... alias_index=4
3635 //
3636 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist,
3637 GrowableArray<ArrayCopyNode*> &arraycopy_worklist,
3638 GrowableArray<MergeMemNode*> &mergemem_worklist,
3639 Unique_Node_List &reducible_merges) {
3640 DEBUG_ONLY(Unique_Node_List reduced_merges;)
3641 GrowableArray<Node *> memnode_worklist;
3642 GrowableArray<PhiNode *> orig_phis;
3643 PhaseIterGVN *igvn = _igvn;
3644 uint new_index_start = (uint) _compile->num_alias_types();
3645 VectorSet visited;
3646 ideal_nodes.clear(); // Reset for use with set_map/get_map.
3647 uint unique_old = _compile->unique();
3648
3649 // Phase 1: Process possible allocations from alloc_worklist.
3650 // Create instance types for the CheckCastPP for allocations where possible.
3651 //
3652 // (Note: don't forget to change the order of the second AddP node on
3653 // the alloc_worklist if the order of the worklist processing is changed,
3654 // see the comment in find_second_addp().)
3655 //
3656 while (alloc_worklist.length() != 0) {
3657 Node *n = alloc_worklist.pop();
3658 uint ni = n->_idx;
3659 if (n->is_Call()) {
3660 CallNode *alloc = n->as_Call();
3661 // copy escape information to call node
3662 PointsToNode* ptn = ptnode_adr(alloc->_idx);
3663 PointsToNode::EscapeState es = ptn->escape_state();
3664 // We have an allocation or call which returns a Java object,
3665 // see if it is non-escaped.
3666 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) {
3667 continue;
3668 }
3669 // Find CheckCastPP for the allocate or for the return value of a call
3670 n = alloc->result_cast();
3671 if (n == nullptr) { // No uses except Initialize node
3672 if (alloc->is_Allocate()) {
3673 // Set the scalar_replaceable flag for allocation
3674 // so it could be eliminated if it has no uses.
3675 alloc->as_Allocate()->_is_scalar_replaceable = true;
3676 }
3677 continue;
3678 }
3679 if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
3680 // we could reach here for allocate case if one init is associated with many allocs.
3681 if (alloc->is_Allocate()) {
3682 alloc->as_Allocate()->_is_scalar_replaceable = false;
3683 }
3684 continue;
3685 }
3686
3687 // The inline code for Object.clone() casts the allocation result to
3688 // java.lang.Object and then to the actual type of the allocated
3689 // object. Detect this case and use the second cast.
3690 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
3691 // the allocation result is cast to java.lang.Object and then
3692 // to the actual Array type.
3693 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
3694 && (alloc->is_AllocateArray() ||
3695 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeInstKlassPtr::OBJECT)) {
3696 Node *cast2 = nullptr;
3697 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3698 Node *use = n->fast_out(i);
3699 if (use->is_CheckCastPP()) {
3700 cast2 = use;
3701 break;
3702 }
3703 }
3704 if (cast2 != nullptr) {
3705 n = cast2;
3706 } else {
3707 // Non-scalar replaceable if the allocation type is unknown statically
3708 // (reflection allocation), the object can't be restored during
3709 // deoptimization without precise type.
3710 continue;
3711 }
3712 }
3713
3714 const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
3715 if (t == nullptr) {
3716 continue; // not a TypeOopPtr
3717 }
3718 if (!t->klass_is_exact()) {
3719 continue; // not an unique type
3720 }
3721 if (alloc->is_Allocate()) {
3722 // Set the scalar_replaceable flag for allocation
3723 // so it could be eliminated.
3724 alloc->as_Allocate()->_is_scalar_replaceable = true;
3725 }
3726 set_escape_state(ptnode_adr(n->_idx), es NOT_PRODUCT(COMMA trace_propagate_message(ptn))); // CheckCastPP escape state
3727 // in order for an object to be scalar-replaceable, it must be:
3728 // - a direct allocation (not a call returning an object)
3729 // - non-escaping
3730 // - eligible to be a unique type
3731 // - not determined to be ineligible by escape analysis
3732 set_map(alloc, n);
3733 set_map(n, alloc);
3734 const TypeOopPtr* tinst = t->cast_to_instance_id(ni);
3735 igvn->hash_delete(n);
3736 igvn->set_type(n, tinst);
3737 n->raise_bottom_type(tinst);
3738 igvn->hash_insert(n);
3739 record_for_optimizer(n);
3740 // Allocate an alias index for the header fields. Accesses to
3741 // the header emitted during macro expansion wouldn't have
3742 // correct memory state otherwise.
3743 _compile->get_alias_index(tinst->add_offset(oopDesc::mark_offset_in_bytes()));
3744 _compile->get_alias_index(tinst->add_offset(oopDesc::klass_offset_in_bytes()));
3745 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) {
3746
3747 // First, put on the worklist all Field edges from Connection Graph
3748 // which is more accurate than putting immediate users from Ideal Graph.
3749 for (EdgeIterator e(ptn); e.has_next(); e.next()) {
3750 PointsToNode* tgt = e.get();
3751 if (tgt->is_Arraycopy()) {
3752 continue;
3753 }
3754 Node* use = tgt->ideal_node();
3755 assert(tgt->is_Field() && use->is_AddP(),
3756 "only AddP nodes are Field edges in CG");
3757 if (use->outcnt() > 0) { // Don't process dead nodes
3758 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
3759 if (addp2 != nullptr) {
3760 assert(alloc->is_AllocateArray(),"array allocation was expected");
3761 alloc_worklist.append_if_missing(addp2);
3762 }
3763 alloc_worklist.append_if_missing(use);
3764 }
3765 }
3766
3767 // An allocation may have an Initialize which has raw stores. Scan
3768 // the users of the raw allocation result and push AddP users
3769 // on alloc_worklist.
3770 Node *raw_result = alloc->proj_out_or_null(TypeFunc::Parms);
3771 assert (raw_result != nullptr, "must have an allocation result");
3772 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
3773 Node *use = raw_result->fast_out(i);
3774 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
3775 Node* addp2 = find_second_addp(use, raw_result);
3776 if (addp2 != nullptr) {
3777 assert(alloc->is_AllocateArray(),"array allocation was expected");
3778 alloc_worklist.append_if_missing(addp2);
3779 }
3780 alloc_worklist.append_if_missing(use);
3781 } else if (use->is_MemBar()) {
3782 memnode_worklist.append_if_missing(use);
3783 }
3784 }
3785 }
3786 } else if (n->is_AddP()) {
3787 Node* addp_base = get_addp_base(n);
3788 if (addp_base != nullptr && reducible_merges.member(addp_base)) {
3789 // This AddP will go away when we reduce the the Phi
3790 continue;
3791 }
3792 JavaObjectNode* jobj = unique_java_object(addp_base);
3793 if (jobj == nullptr || jobj == phantom_obj) {
3794 #ifdef ASSERT
3795 ptnode_adr(get_addp_base(n)->_idx)->dump();
3796 ptnode_adr(n->_idx)->dump();
3797 assert(jobj != nullptr && jobj != phantom_obj, "escaped allocation");
3798 #endif
3799 _compile->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
3800 return;
3801 }
3802 Node *base = get_map(jobj->idx()); // CheckCastPP node
3803 if (!split_AddP(n, base)) continue; // wrong type from dead path
3804 } else if (n->is_Phi() ||
3805 n->is_CheckCastPP() ||
3806 n->is_EncodeP() ||
3807 n->is_DecodeN() ||
3808 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
3809 if (visited.test_set(n->_idx)) {
3810 assert(n->is_Phi(), "loops only through Phi's");
3811 continue; // already processed
3812 }
3813 // Reducible Phi's will be removed from the graph after split_unique_types finishes
3814 if (reducible_merges.member(n)) {
3815 // Split loads through phi
3816 reduce_phi_on_field_access(n->as_Phi(), alloc_worklist);
3817 #ifdef ASSERT
3818 if (VerifyReduceAllocationMerges) {
3819 reduced_merges.push(n);
3820 }
3821 #endif
3822 continue;
3823 }
3824 JavaObjectNode* jobj = unique_java_object(n);
3825 if (jobj == nullptr || jobj == phantom_obj) {
3826 #ifdef ASSERT
3827 ptnode_adr(n->_idx)->dump();
3828 assert(jobj != nullptr && jobj != phantom_obj, "escaped allocation");
3829 #endif
3830 _compile->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
3831 return;
3832 } else {
3833 Node *val = get_map(jobj->idx()); // CheckCastPP node
3834 TypeNode *tn = n->as_Type();
3835 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr();
3836 assert(tinst != nullptr && tinst->is_known_instance() &&
3837 tinst->instance_id() == jobj->idx() , "instance type expected.");
3838
3839 const Type *tn_type = igvn->type(tn);
3840 const TypeOopPtr *tn_t;
3841 if (tn_type->isa_narrowoop()) {
3842 tn_t = tn_type->make_ptr()->isa_oopptr();
3843 } else {
3844 tn_t = tn_type->isa_oopptr();
3845 }
3846 if (tn_t != nullptr && tinst->maybe_java_subtype_of(tn_t)) {
3847 if (tn_type->isa_narrowoop()) {
3848 tn_type = tinst->make_narrowoop();
3849 } else {
3850 tn_type = tinst;
3851 }
3852 igvn->hash_delete(tn);
3853 igvn->set_type(tn, tn_type);
3854 tn->set_type(tn_type);
3855 igvn->hash_insert(tn);
3856 record_for_optimizer(n);
3857 } else {
3858 assert(tn_type == TypePtr::NULL_PTR ||
3859 tn_t != nullptr && !tinst->maybe_java_subtype_of(tn_t),
3860 "unexpected type");
3861 continue; // Skip dead path with different type
3862 }
3863 }
3864 } else {
3865 debug_only(n->dump();)
3866 assert(false, "EA: unexpected node");
3867 continue;
3868 }
3869 // push allocation's users on appropriate worklist
3870 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3871 Node *use = n->fast_out(i);
3872 if(use->is_Mem() && use->in(MemNode::Address) == n) {
3873 // Load/store to instance's field
3874 memnode_worklist.append_if_missing(use);
3875 } else if (use->is_MemBar()) {
3876 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3877 memnode_worklist.append_if_missing(use);
3878 }
3879 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
3880 Node* addp2 = find_second_addp(use, n);
3881 if (addp2 != nullptr) {
3882 alloc_worklist.append_if_missing(addp2);
3883 }
3884 alloc_worklist.append_if_missing(use);
3885 } else if (use->is_Phi() ||
3886 use->is_CheckCastPP() ||
3887 use->is_EncodeNarrowPtr() ||
3888 use->is_DecodeNarrowPtr() ||
3889 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
3890 alloc_worklist.append_if_missing(use);
3891 #ifdef ASSERT
3892 } else if (use->is_Mem()) {
3893 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
3894 } else if (use->is_MergeMem()) {
3895 assert(mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3896 } else if (use->is_SafePoint()) {
3897 // Look for MergeMem nodes for calls which reference unique allocation
3898 // (through CheckCastPP nodes) even for debug info.
3899 Node* m = use->in(TypeFunc::Memory);
3900 if (m->is_MergeMem()) {
3901 assert(mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3902 }
3903 } else if (use->Opcode() == Op_EncodeISOArray) {
3904 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3905 // EncodeISOArray overwrites destination array
3906 memnode_worklist.append_if_missing(use);
3907 }
3908 } else {
3909 uint op = use->Opcode();
3910 if ((op == Op_StrCompressedCopy || op == Op_StrInflatedCopy) &&
3911 (use->in(MemNode::Memory) == n)) {
3912 // They overwrite memory edge corresponding to destination array,
3913 memnode_worklist.append_if_missing(use);
3914 } else if (!(op == Op_CmpP || op == Op_Conv2B ||
3915 op == Op_CastP2X || op == Op_StoreCM ||
3916 op == Op_FastLock || op == Op_AryEq ||
3917 op == Op_StrComp || op == Op_CountPositives ||
3918 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3919 op == Op_StrEquals || op == Op_VectorizedHashCode ||
3920 op == Op_StrIndexOf || op == Op_StrIndexOfChar ||
3921 op == Op_SubTypeCheck ||
3922 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use))) {
3923 n->dump();
3924 use->dump();
3925 assert(false, "EA: missing allocation reference path");
3926 }
3927 #endif
3928 }
3929 }
3930
3931 }
3932
3933 #ifdef ASSERT
3934 if (VerifyReduceAllocationMerges) {
3935 // At this point reducible Phis shouldn't have AddP users anymore; only SafePoints.
3936 for (uint i = 0; i < reducible_merges.size(); i++) {
3937 Node* phi = reducible_merges.at(i);
3938
3939 if (!reduced_merges.member(phi)) {
3940 phi->dump(2);
3941 phi->dump(-2);
3942 assert(false, "This reducible merge wasn't reduced.");
3943 }
3944
3945 for (DUIterator_Fast jmax, j = phi->fast_outs(jmax); j < jmax; j++) {
3946 Node* use = phi->fast_out(j);
3947 if (!use->is_SafePoint()) {
3948 phi->dump(2);
3949 phi->dump(-2);
3950 assert(false, "Unexpected user of reducible Phi -> %d:%s:%d", use->_idx, use->Name(), use->outcnt());
3951 }
3952 }
3953 }
3954 }
3955 #endif
3956
3957 // Go over all ArrayCopy nodes and if one of the inputs has a unique
3958 // type, record it in the ArrayCopy node so we know what memory this
3959 // node uses/modified.
3960 for (int next = 0; next < arraycopy_worklist.length(); next++) {
3961 ArrayCopyNode* ac = arraycopy_worklist.at(next);
3962 Node* dest = ac->in(ArrayCopyNode::Dest);
3963 if (dest->is_AddP()) {
3964 dest = get_addp_base(dest);
3965 }
3966 JavaObjectNode* jobj = unique_java_object(dest);
3967 if (jobj != nullptr) {
3968 Node *base = get_map(jobj->idx());
3969 if (base != nullptr) {
3970 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3971 ac->_dest_type = base_t;
3972 }
3973 }
3974 Node* src = ac->in(ArrayCopyNode::Src);
3975 if (src->is_AddP()) {
3976 src = get_addp_base(src);
3977 }
3978 jobj = unique_java_object(src);
3979 if (jobj != nullptr) {
3980 Node* base = get_map(jobj->idx());
3981 if (base != nullptr) {
3982 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3983 ac->_src_type = base_t;
3984 }
3985 }
3986 }
3987
3988 // New alias types were created in split_AddP().
3989 uint new_index_end = (uint) _compile->num_alias_types();
3990
3991 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
3992 // compute new values for Memory inputs (the Memory inputs are not
3993 // actually updated until phase 4.)
3994 if (memnode_worklist.length() == 0)
3995 return; // nothing to do
3996 while (memnode_worklist.length() != 0) {
3997 Node *n = memnode_worklist.pop();
3998 if (visited.test_set(n->_idx)) {
3999 continue;
4000 }
4001 if (n->is_Phi() || n->is_ClearArray()) {
4002 // we don't need to do anything, but the users must be pushed
4003 } else if (n->is_MemBar()) { // Initialize, MemBar nodes
4004 // we don't need to do anything, but the users must be pushed
4005 n = n->as_MemBar()->proj_out_or_null(TypeFunc::Memory);
4006 if (n == nullptr) {
4007 continue;
4008 }
4009 } else if (n->Opcode() == Op_StrCompressedCopy ||
4010 n->Opcode() == Op_EncodeISOArray) {
4011 // get the memory projection
4012 n = n->find_out_with(Op_SCMemProj);
4013 assert(n != nullptr && n->Opcode() == Op_SCMemProj, "memory projection required");
4014 } else {
4015 assert(n->is_Mem(), "memory node required.");
4016 Node *addr = n->in(MemNode::Address);
4017 const Type *addr_t = igvn->type(addr);
4018 if (addr_t == Type::TOP) {
4019 continue;
4020 }
4021 assert (addr_t->isa_ptr() != nullptr, "pointer type required.");
4022 int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
4023 assert ((uint)alias_idx < new_index_end, "wrong alias index");
4024 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis);
4025 if (_compile->failing()) {
4026 return;
4027 }
4028 if (mem != n->in(MemNode::Memory)) {
4029 // We delay the memory edge update since we need old one in
4030 // MergeMem code below when instances memory slices are separated.
4031 set_map(n, mem);
4032 }
4033 if (n->is_Load()) {
4034 continue; // don't push users
4035 } else if (n->is_LoadStore()) {
4036 // get the memory projection
4037 n = n->find_out_with(Op_SCMemProj);
4038 assert(n != nullptr && n->Opcode() == Op_SCMemProj, "memory projection required");
4039 }
4040 }
4041 // push user on appropriate worklist
4042 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
4043 Node *use = n->fast_out(i);
4044 if (use->is_Phi() || use->is_ClearArray()) {
4045 memnode_worklist.append_if_missing(use);
4046 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) {
4047 if (use->Opcode() == Op_StoreCM) { // Ignore cardmark stores
4048 continue;
4049 }
4050 memnode_worklist.append_if_missing(use);
4051 } else if (use->is_MemBar()) {
4052 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
4053 memnode_worklist.append_if_missing(use);
4054 }
4055 #ifdef ASSERT
4056 } else if(use->is_Mem()) {
4057 assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
4058 } else if (use->is_MergeMem()) {
4059 assert(mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
4060 } else if (use->Opcode() == Op_EncodeISOArray) {
4061 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
4062 // EncodeISOArray overwrites destination array
4063 memnode_worklist.append_if_missing(use);
4064 }
4065 } else {
4066 uint op = use->Opcode();
4067 if ((use->in(MemNode::Memory) == n) &&
4068 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) {
4069 // They overwrite memory edge corresponding to destination array,
4070 memnode_worklist.append_if_missing(use);
4071 } else if (!(BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use) ||
4072 op == Op_AryEq || op == Op_StrComp || op == Op_CountPositives ||
4073 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy || op == Op_VectorizedHashCode ||
4074 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) {
4075 n->dump();
4076 use->dump();
4077 assert(false, "EA: missing memory path");
4078 }
4079 #endif
4080 }
4081 }
4082 }
4083
4084 // Phase 3: Process MergeMem nodes from mergemem_worklist.
4085 // Walk each memory slice moving the first node encountered of each
4086 // instance type to the input corresponding to its alias index.
4087 uint length = mergemem_worklist.length();
4088 for( uint next = 0; next < length; ++next ) {
4089 MergeMemNode* nmm = mergemem_worklist.at(next);
4090 assert(!visited.test_set(nmm->_idx), "should not be visited before");
4091 // Note: we don't want to use MergeMemStream here because we only want to
4092 // scan inputs which exist at the start, not ones we add during processing.
4093 // Note 2: MergeMem may already contains instance memory slices added
4094 // during find_inst_mem() call when memory nodes were processed above.
4095 igvn->hash_delete(nmm);
4096 uint nslices = MIN2(nmm->req(), new_index_start);
4097 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
4098 Node* mem = nmm->in(i);
4099 Node* cur = nullptr;
4100 if (mem == nullptr || mem->is_top()) {
4101 continue;
4102 }
4103 // First, update mergemem by moving memory nodes to corresponding slices
4104 // if their type became more precise since this mergemem was created.
4105 while (mem->is_Mem()) {
4106 const Type *at = igvn->type(mem->in(MemNode::Address));
4107 if (at != Type::TOP) {
4108 assert (at->isa_ptr() != nullptr, "pointer type required.");
4109 uint idx = (uint)_compile->get_alias_index(at->is_ptr());
4110 if (idx == i) {
4111 if (cur == nullptr) {
4112 cur = mem;
4113 }
4114 } else {
4115 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
4116 nmm->set_memory_at(idx, mem);
4117 }
4118 }
4119 }
4120 mem = mem->in(MemNode::Memory);
4121 }
4122 nmm->set_memory_at(i, (cur != nullptr) ? cur : mem);
4123 // Find any instance of the current type if we haven't encountered
4124 // already a memory slice of the instance along the memory chain.
4125 for (uint ni = new_index_start; ni < new_index_end; ni++) {
4126 if((uint)_compile->get_general_index(ni) == i) {
4127 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
4128 if (nmm->is_empty_memory(m)) {
4129 Node* result = find_inst_mem(mem, ni, orig_phis);
4130 if (_compile->failing()) {
4131 return;
4132 }
4133 nmm->set_memory_at(ni, result);
4134 }
4135 }
4136 }
4137 }
4138 // Find the rest of instances values
4139 for (uint ni = new_index_start; ni < new_index_end; ni++) {
4140 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
4141 Node* result = step_through_mergemem(nmm, ni, tinst);
4142 if (result == nmm->base_memory()) {
4143 // Didn't find instance memory, search through general slice recursively.
4144 result = nmm->memory_at(_compile->get_general_index(ni));
4145 result = find_inst_mem(result, ni, orig_phis);
4146 if (_compile->failing()) {
4147 return;
4148 }
4149 nmm->set_memory_at(ni, result);
4150 }
4151 }
4152 igvn->hash_insert(nmm);
4153 record_for_optimizer(nmm);
4154 }
4155
4156 // Phase 4: Update the inputs of non-instance memory Phis and
4157 // the Memory input of memnodes
4158 // First update the inputs of any non-instance Phi's from
4159 // which we split out an instance Phi. Note we don't have
4160 // to recursively process Phi's encountered on the input memory
4161 // chains as is done in split_memory_phi() since they will
4162 // also be processed here.
4163 for (int j = 0; j < orig_phis.length(); j++) {
4164 PhiNode *phi = orig_phis.at(j);
4165 int alias_idx = _compile->get_alias_index(phi->adr_type());
4166 igvn->hash_delete(phi);
4167 for (uint i = 1; i < phi->req(); i++) {
4168 Node *mem = phi->in(i);
4169 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis);
4170 if (_compile->failing()) {
4171 return;
4172 }
4173 if (mem != new_mem) {
4174 phi->set_req(i, new_mem);
4175 }
4176 }
4177 igvn->hash_insert(phi);
4178 record_for_optimizer(phi);
4179 }
4180
4181 // Update the memory inputs of MemNodes with the value we computed
4182 // in Phase 2 and move stores memory users to corresponding memory slices.
4183 // Disable memory split verification code until the fix for 6984348.
4184 // Currently it produces false negative results since it does not cover all cases.
4185 #if 0 // ifdef ASSERT
4186 visited.Reset();
4187 Node_Stack old_mems(arena, _compile->unique() >> 2);
4188 #endif
4189 for (uint i = 0; i < ideal_nodes.size(); i++) {
4190 Node* n = ideal_nodes.at(i);
4191 Node* nmem = get_map(n->_idx);
4192 assert(nmem != nullptr, "sanity");
4193 if (n->is_Mem()) {
4194 #if 0 // ifdef ASSERT
4195 Node* old_mem = n->in(MemNode::Memory);
4196 if (!visited.test_set(old_mem->_idx)) {
4197 old_mems.push(old_mem, old_mem->outcnt());
4198 }
4199 #endif
4200 assert(n->in(MemNode::Memory) != nmem, "sanity");
4201 if (!n->is_Load()) {
4202 // Move memory users of a store first.
4203 move_inst_mem(n, orig_phis);
4204 }
4205 // Now update memory input
4206 igvn->hash_delete(n);
4207 n->set_req(MemNode::Memory, nmem);
4208 igvn->hash_insert(n);
4209 record_for_optimizer(n);
4210 } else {
4211 assert(n->is_Allocate() || n->is_CheckCastPP() ||
4212 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()");
4213 }
4214 }
4215 #if 0 // ifdef ASSERT
4216 // Verify that memory was split correctly
4217 while (old_mems.is_nonempty()) {
4218 Node* old_mem = old_mems.node();
4219 uint old_cnt = old_mems.index();
4220 old_mems.pop();
4221 assert(old_cnt == old_mem->outcnt(), "old mem could be lost");
4222 }
4223 #endif
4224 }
4225
4226 #ifndef PRODUCT
4227 int ConnectionGraph::_no_escape_counter = 0;
4228 int ConnectionGraph::_arg_escape_counter = 0;
4229 int ConnectionGraph::_global_escape_counter = 0;
4230
4231 static const char *node_type_names[] = {
4232 "UnknownType",
4233 "JavaObject",
4234 "LocalVar",
4235 "Field",
4236 "Arraycopy"
4237 };
4238
4239 static const char *esc_names[] = {
4240 "UnknownEscape",
4241 "NoEscape",
4242 "ArgEscape",
4243 "GlobalEscape"
4244 };
4245
4246 void PointsToNode::dump_header(bool print_state, outputStream* out) const {
4247 NodeType nt = node_type();
4248 out->print("%s(%d) ", node_type_names[(int) nt], _pidx);
4249 if (print_state) {
4250 EscapeState es = escape_state();
4251 EscapeState fields_es = fields_escape_state();
4252 out->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]);
4253 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) {
4254 out->print("NSR ");
4255 }
4256 }
4257 }
4258
4259 void PointsToNode::dump(bool print_state, outputStream* out, bool newline) const {
4260 dump_header(print_state, out);
4261 if (is_Field()) {
4262 FieldNode* f = (FieldNode*)this;
4263 if (f->is_oop()) {
4264 out->print("oop ");
4265 }
4266 if (f->offset() > 0) {
4267 out->print("+%d ", f->offset());
4268 }
4269 out->print("(");
4270 for (BaseIterator i(f); i.has_next(); i.next()) {
4271 PointsToNode* b = i.get();
4272 out->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : ""));
4273 }
4274 out->print(" )");
4275 }
4276 out->print("[");
4277 for (EdgeIterator i(this); i.has_next(); i.next()) {
4278 PointsToNode* e = i.get();
4279 out->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : "");
4280 }
4281 out->print(" [");
4282 for (UseIterator i(this); i.has_next(); i.next()) {
4283 PointsToNode* u = i.get();
4284 bool is_base = false;
4285 if (PointsToNode::is_base_use(u)) {
4286 is_base = true;
4287 u = PointsToNode::get_use_node(u)->as_Field();
4288 }
4289 out->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : "");
4290 }
4291 out->print(" ]] ");
4292 if (_node == nullptr) {
4293 out->print("<null>%s", newline ? "\n" : "");
4294 } else {
4295 _node->dump(newline ? "\n" : "", false, out);
4296 }
4297 }
4298
4299 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) {
4300 bool first = true;
4301 int ptnodes_length = ptnodes_worklist.length();
4302 for (int i = 0; i < ptnodes_length; i++) {
4303 PointsToNode *ptn = ptnodes_worklist.at(i);
4304 if (ptn == nullptr || !ptn->is_JavaObject()) {
4305 continue;
4306 }
4307 PointsToNode::EscapeState es = ptn->escape_state();
4308 if ((es != PointsToNode::NoEscape) && !Verbose) {
4309 continue;
4310 }
4311 Node* n = ptn->ideal_node();
4312 if (n->is_Allocate() || (n->is_CallStaticJava() &&
4313 n->as_CallStaticJava()->is_boxing_method())) {
4314 if (first) {
4315 tty->cr();
4316 tty->print("======== Connection graph for ");
4317 _compile->method()->print_short_name();
4318 tty->cr();
4319 tty->print_cr("invocation #%d: %d iterations and %f sec to build connection graph with %d nodes and worklist size %d",
4320 _invocation, _build_iterations, _build_time, nodes_size(), ptnodes_worklist.length());
4321 tty->cr();
4322 first = false;
4323 }
4324 ptn->dump();
4325 // Print all locals and fields which reference this allocation
4326 for (UseIterator j(ptn); j.has_next(); j.next()) {
4327 PointsToNode* use = j.get();
4328 if (use->is_LocalVar()) {
4329 use->dump(Verbose);
4330 } else if (Verbose) {
4331 use->dump();
4332 }
4333 }
4334 tty->cr();
4335 }
4336 }
4337 }
4338
4339 void ConnectionGraph::print_statistics() {
4340 tty->print_cr("No escape = %d, Arg escape = %d, Global escape = %d", Atomic::load(&_no_escape_counter), Atomic::load(&_arg_escape_counter), Atomic::load(&_global_escape_counter));
4341 }
4342
4343 void ConnectionGraph::escape_state_statistics(GrowableArray<JavaObjectNode*>& java_objects_worklist) {
4344 if (!PrintOptoStatistics || (_invocation > 0)) { // Collect data only for the first invocation
4345 return;
4346 }
4347 for (int next = 0; next < java_objects_worklist.length(); ++next) {
4348 JavaObjectNode* ptn = java_objects_worklist.at(next);
4349 if (ptn->ideal_node()->is_Allocate()) {
4350 if (ptn->escape_state() == PointsToNode::NoEscape) {
4351 Atomic::inc(&ConnectionGraph::_no_escape_counter);
4352 } else if (ptn->escape_state() == PointsToNode::ArgEscape) {
4353 Atomic::inc(&ConnectionGraph::_arg_escape_counter);
4354 } else if (ptn->escape_state() == PointsToNode::GlobalEscape) {
4355 Atomic::inc(&ConnectionGraph::_global_escape_counter);
4356 } else {
4357 assert(false, "Unexpected Escape State");
4358 }
4359 }
4360 }
4361 }
4362
4363 void ConnectionGraph::trace_es_update_helper(PointsToNode* ptn, PointsToNode::EscapeState es, bool fields, const char* reason) const {
4364 if (_compile->directive()->TraceEscapeAnalysisOption) {
4365 assert(ptn != nullptr, "should not be null");
4366 assert(reason != nullptr, "should not be null");
4367 ptn->dump_header(true);
4368 PointsToNode::EscapeState new_es = fields ? ptn->escape_state() : es;
4369 PointsToNode::EscapeState new_fields_es = fields ? es : ptn->fields_escape_state();
4370 tty->print_cr("-> %s(%s) %s", esc_names[(int)new_es], esc_names[(int)new_fields_es], reason);
4371 }
4372 }
4373
4374 const char* ConnectionGraph::trace_propagate_message(PointsToNode* from) const {
4375 if (_compile->directive()->TraceEscapeAnalysisOption) {
4376 stringStream ss;
4377 ss.print("propagated from: ");
4378 from->dump(true, &ss, false);
4379 return ss.as_string();
4380 } else {
4381 return nullptr;
4382 }
4383 }
4384
4385 const char* ConnectionGraph::trace_arg_escape_message(CallNode* call) const {
4386 if (_compile->directive()->TraceEscapeAnalysisOption) {
4387 stringStream ss;
4388 ss.print("escapes as arg to:");
4389 call->dump("", false, &ss);
4390 return ss.as_string();
4391 } else {
4392 return nullptr;
4393 }
4394 }
4395
4396 const char* ConnectionGraph::trace_merged_message(PointsToNode* other) const {
4397 if (_compile->directive()->TraceEscapeAnalysisOption) {
4398 stringStream ss;
4399 ss.print("is merged with other object: ");
4400 other->dump_header(true, &ss);
4401 return ss.as_string();
4402 } else {
4403 return nullptr;
4404 }
4405 }
4406
4407 #endif
4408
4409 void ConnectionGraph::record_for_optimizer(Node *n) {
4410 _igvn->_worklist.push(n);
4411 _igvn->add_users_to_worklist(n);
4412 }