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