1 /*
2 * Copyright (c) 2005, 2026, 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 "ci/bcEscapeAnalyzer.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "gc/shared/barrierSet.hpp"
28 #include "gc/shared/c2/barrierSetC2.hpp"
29 #include "libadt/vectset.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/metaspace.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "opto/arraycopynode.hpp"
34 #include "opto/c2compiler.hpp"
35 #include "opto/callnode.hpp"
36 #include "opto/castnode.hpp"
37 #include "opto/cfgnode.hpp"
38 #include "opto/compile.hpp"
39 #include "opto/escape.hpp"
40 #include "opto/inlinetypenode.hpp"
41 #include "opto/locknode.hpp"
42 #include "opto/macro.hpp"
43 #include "opto/movenode.hpp"
44 #include "opto/narrowptrnode.hpp"
45 #include "opto/phaseX.hpp"
46 #include "opto/rootnode.hpp"
47 #include "utilities/macros.hpp"
48
49 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn, int invocation) :
50 // If ReduceAllocationMerges is enabled we might call split_through_phi during
51 // split_unique_types and that will create additional nodes that need to be
52 // pushed to the ConnectionGraph. The code below bumps the initial capacity of
53 // _nodes by 10% to account for these additional nodes. If capacity is exceeded
54 // the array will be reallocated.
55 _nodes(C->comp_arena(), C->do_reduce_allocation_merges() ? C->unique()*1.10 : C->unique(), C->unique(), nullptr),
56 _in_worklist(C->comp_arena()),
57 _next_pidx(0),
58 _collecting(true),
59 _verify(false),
60 _compile(C),
61 _igvn(igvn),
62 _invocation(invocation),
63 _build_iterations(0),
64 _build_time(0.),
65 _node_map(C->comp_arena()) {
66 // Add unknown java object.
67 add_java_object(C->top(), PointsToNode::GlobalEscape);
68 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject();
69 set_not_scalar_replaceable(phantom_obj NOT_PRODUCT(COMMA "Phantom object"));
70 // Add ConP and ConN null oop nodes
71 Node* oop_null = igvn->zerocon(T_OBJECT);
72 assert(oop_null->_idx < nodes_size(), "should be created already");
73 add_java_object(oop_null, PointsToNode::NoEscape);
74 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject();
75 set_not_scalar_replaceable(null_obj NOT_PRODUCT(COMMA "Null object"));
76 if (UseCompressedOops) {
77 Node* noop_null = igvn->zerocon(T_NARROWOOP);
78 assert(noop_null->_idx < nodes_size(), "should be created already");
79 map_ideal_node(noop_null, null_obj);
80 }
81 }
82
83 bool ConnectionGraph::has_candidates(Compile *C) {
84 // EA brings benefits only when the code has allocations and/or locks which
85 // are represented by ideal Macro nodes.
86 int cnt = C->macro_count();
87 for (int i = 0; i < cnt; i++) {
88 Node *n = C->macro_node(i);
89 if (n->is_Allocate()) {
90 return true;
91 }
92 if (n->is_Lock()) {
93 Node* obj = n->as_Lock()->obj_node()->uncast();
94 if (!(obj->is_Parm() || obj->is_Con())) {
95 return true;
96 }
97 }
98 if (n->is_CallStaticJava() &&
99 n->as_CallStaticJava()->is_boxing_method()) {
100 return true;
101 }
102 }
103 return false;
104 }
105
106 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
107 Compile::TracePhase tp(Phase::_t_escapeAnalysis);
108 ResourceMark rm;
109
110 // Add ConP and ConN null oop nodes before ConnectionGraph construction
111 // to create space for them in ConnectionGraph::_nodes[].
112 Node* oop_null = igvn->zerocon(T_OBJECT);
113 Node* noop_null = igvn->zerocon(T_NARROWOOP);
114 int invocation = 0;
115 if (C->congraph() != nullptr) {
116 invocation = C->congraph()->_invocation + 1;
117 }
118 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn, invocation);
119 NOT_PRODUCT(if (C->should_print_igv(/* Any level */ 1)) C->igv_printer()->set_congraph(congraph);)
120 // Perform escape analysis
121 if (congraph->compute_escape()) {
122 // There are non escaping objects.
123 C->set_congraph(congraph);
124 }
125 NOT_PRODUCT(if (C->should_print_igv(/* Any level */ 1)) C->igv_printer()->set_congraph(nullptr);)
126 // Cleanup.
127 if (oop_null->outcnt() == 0) {
128 igvn->hash_delete(oop_null);
129 }
130 if (noop_null->outcnt() == 0) {
131 igvn->hash_delete(noop_null);
132 }
133
134 C->print_method(PHASE_AFTER_EA, 2);
135 }
136
137 bool ConnectionGraph::compute_escape() {
138 Compile* C = _compile;
139 PhaseGVN* igvn = _igvn;
140
141 // Worklists used by EA.
142 Unique_Node_List delayed_worklist;
143 Unique_Node_List reducible_merges;
144 GrowableArray<Node*> alloc_worklist;
145 GrowableArray<Node*> ptr_cmp_worklist;
146 GrowableArray<MemBarStoreStoreNode*> storestore_worklist;
147 GrowableArray<ArrayCopyNode*> arraycopy_worklist;
148 GrowableArray<PointsToNode*> ptnodes_worklist;
149 GrowableArray<JavaObjectNode*> java_objects_worklist;
150 GrowableArray<JavaObjectNode*> non_escaped_allocs_worklist;
151 GrowableArray<FieldNode*> oop_fields_worklist;
152 GrowableArray<SafePointNode*> sfn_worklist;
153 GrowableArray<MergeMemNode*> mergemem_worklist;
154 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; )
155
156 { Compile::TracePhase tp(Phase::_t_connectionGraph);
157
158 // 1. Populate Connection Graph (CG) with PointsTo nodes.
159 ideal_nodes.map(C->live_nodes(), nullptr); // preallocate space
160 // Initialize worklist
161 if (C->root() != nullptr) {
162 ideal_nodes.push(C->root());
163 }
164 // Processed ideal nodes are unique on ideal_nodes list
165 // but several ideal nodes are mapped to the phantom_obj.
166 // To avoid duplicated entries on the following worklists
167 // add the phantom_obj only once to them.
168 ptnodes_worklist.append(phantom_obj);
169 java_objects_worklist.append(phantom_obj);
170 for( uint next = 0; next < ideal_nodes.size(); ++next ) {
171 Node* n = ideal_nodes.at(next);
172 if ((n->Opcode() == Op_LoadX || n->Opcode() == Op_StoreX) &&
173 !n->in(MemNode::Address)->is_AddP() &&
174 _igvn->type(n->in(MemNode::Address))->isa_oopptr()) {
175 // Load/Store at mark work address is at offset 0 so has no AddP which confuses EA
176 Node* addp = AddPNode::make_with_base(n->in(MemNode::Address), n->in(MemNode::Address), _igvn->MakeConX(0));
177 _igvn->register_new_node_with_optimizer(addp);
178 _igvn->replace_input_of(n, MemNode::Address, addp);
179 ideal_nodes.push(addp);
180 _nodes.at_put_grow(addp->_idx, nullptr, nullptr);
181 }
182 // Create PointsTo nodes and add them to Connection Graph. Called
183 // only once per ideal node since ideal_nodes is Unique_Node list.
184 add_node_to_connection_graph(n, &delayed_worklist);
185 PointsToNode* ptn = ptnode_adr(n->_idx);
186 if (ptn != nullptr && ptn != phantom_obj) {
187 ptnodes_worklist.append(ptn);
188 if (ptn->is_JavaObject()) {
189 java_objects_worklist.append(ptn->as_JavaObject());
190 if ((n->is_Allocate() || n->is_CallStaticJava()) &&
191 (ptn->escape_state() < PointsToNode::GlobalEscape)) {
192 // Only allocations and java static calls results are interesting.
193 non_escaped_allocs_worklist.append(ptn->as_JavaObject());
194 }
195 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) {
196 oop_fields_worklist.append(ptn->as_Field());
197 }
198 }
199 // Collect some interesting nodes for further use.
200 switch (n->Opcode()) {
201 case Op_MergeMem:
202 // Collect all MergeMem nodes to add memory slices for
203 // scalar replaceable objects in split_unique_types().
204 mergemem_worklist.append(n->as_MergeMem());
205 break;
206 case Op_CmpP:
207 case Op_CmpN:
208 // Collect compare pointers nodes.
209 if (OptimizePtrCompare) {
210 ptr_cmp_worklist.append(n);
211 }
212 break;
213 case Op_MemBarStoreStore:
214 // Collect all MemBarStoreStore nodes so that depending on the
215 // escape status of the associated Allocate node some of them
216 // may be eliminated.
217 if (!UseStoreStoreForCtor || n->req() > MemBarNode::Precedent) {
218 storestore_worklist.append(n->as_MemBarStoreStore());
219 }
220 // If MemBarStoreStore has a precedent edge add it to the worklist (like MemBarRelease)
221 case Op_MemBarRelease:
222 if (n->req() > MemBarNode::Precedent) {
223 record_for_optimizer(n);
224 }
225 break;
226 #ifdef ASSERT
227 case Op_AddP:
228 // Collect address nodes for graph verification.
229 addp_worklist.append(n);
230 break;
231 #endif
232 case Op_ArrayCopy:
233 // Keep a list of ArrayCopy nodes so if one of its input is non
234 // escaping, we can record a unique type
235 arraycopy_worklist.append(n->as_ArrayCopy());
236 break;
237 default:
238 // not interested now, ignore...
239 break;
240 }
241 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
242 Node* m = n->fast_out(i); // Get user
243 ideal_nodes.push(m);
244 }
245 if (n->is_SafePoint()) {
246 sfn_worklist.append(n->as_SafePoint());
247 }
248 }
249
250 #ifndef PRODUCT
251 if (_compile->directive()->TraceEscapeAnalysisOption) {
252 tty->print("+++++ Initial worklist for ");
253 _compile->method()->print_name();
254 tty->print_cr(" (ea_inv=%d)", _invocation);
255 for (int i = 0; i < ptnodes_worklist.length(); i++) {
256 PointsToNode* ptn = ptnodes_worklist.at(i);
257 ptn->dump();
258 }
259 tty->print_cr("+++++ Calculating escape states and scalar replaceability");
260 }
261 #endif
262
263 if (non_escaped_allocs_worklist.length() == 0) {
264 _collecting = false;
265 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
266 return false; // Nothing to do.
267 }
268 // Add final simple edges to graph.
269 while(delayed_worklist.size() > 0) {
270 Node* n = delayed_worklist.pop();
271 add_final_edges(n);
272 }
273
274 #ifdef ASSERT
275 if (VerifyConnectionGraph) {
276 // Verify that no new simple edges could be created and all
277 // local vars has edges.
278 _verify = true;
279 int ptnodes_length = ptnodes_worklist.length();
280 for (int next = 0; next < ptnodes_length; ++next) {
281 PointsToNode* ptn = ptnodes_worklist.at(next);
282 add_final_edges(ptn->ideal_node());
283 if (ptn->is_LocalVar() && ptn->edge_count() == 0) {
284 ptn->dump();
285 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity");
286 }
287 }
288 _verify = false;
289 }
290 #endif
291 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes
292 // processing, calls to CI to resolve symbols (types, fields, methods)
293 // referenced in bytecode. During symbol resolution VM may throw
294 // an exception which CI cleans and converts to compilation failure.
295 if (C->failing()) {
296 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
297 return false;
298 }
299
300 _compile->print_method(PHASE_EA_AFTER_INITIAL_CONGRAPH, 4);
301
302 // 2. Finish Graph construction by propagating references to all
303 // java objects through graph.
304 if (!complete_connection_graph(ptnodes_worklist, non_escaped_allocs_worklist,
305 java_objects_worklist, oop_fields_worklist)) {
306 // All objects escaped or hit time or iterations limits.
307 _collecting = false;
308 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
309 return false;
310 }
311
312 _compile->print_method(PHASE_EA_AFTER_COMPLETE_CONGRAPH, 4);
313
314 // 3. Adjust scalar_replaceable state of nonescaping objects and push
315 // scalar replaceable allocations on alloc_worklist for processing
316 // in split_unique_types().
317 GrowableArray<JavaObjectNode*> jobj_worklist;
318 int non_escaped_length = non_escaped_allocs_worklist.length();
319 bool found_nsr_alloc = false;
320 for (int next = 0; next < non_escaped_length; next++) {
321 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
322 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape);
323 Node* n = ptn->ideal_node();
324 if (n->is_Allocate()) {
325 n->as_Allocate()->_is_non_escaping = noescape;
326 }
327 if (noescape && ptn->scalar_replaceable()) {
328 adjust_scalar_replaceable_state(ptn, reducible_merges);
329 if (ptn->scalar_replaceable()) {
330 jobj_worklist.push(ptn);
331 } else {
332 found_nsr_alloc = true;
333 }
334 }
335 _compile->print_method(PHASE_EA_ADJUST_SCALAR_REPLACEABLE_ITER, 6, n);
336 }
337
338 // Propagate NSR (Not Scalar Replaceable) state.
339 if (found_nsr_alloc) {
340 find_scalar_replaceable_allocs(jobj_worklist, reducible_merges);
341 }
342
343 // alloc_worklist will be processed in reverse push order.
344 // Therefore the reducible Phis will be processed for last and that's what we
345 // want because by then the scalarizable inputs of the merge will already have
346 // an unique instance type.
347 for (uint i = 0; i < reducible_merges.size(); i++ ) {
348 Node* n = reducible_merges.at(i);
349 alloc_worklist.append(n);
350 }
351
352 for (int next = 0; next < jobj_worklist.length(); ++next) {
353 JavaObjectNode* jobj = jobj_worklist.at(next);
354 if (jobj->scalar_replaceable()) {
355 alloc_worklist.append(jobj->ideal_node());
356 }
357 }
358
359 #ifdef ASSERT
360 if (VerifyConnectionGraph) {
361 // Verify that graph is complete - no new edges could be added or needed.
362 verify_connection_graph(ptnodes_worklist, non_escaped_allocs_worklist,
363 java_objects_worklist, addp_worklist);
364 }
365 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build");
366 assert(null_obj->escape_state() == PointsToNode::NoEscape &&
367 null_obj->edge_count() == 0 &&
368 !null_obj->arraycopy_src() &&
369 !null_obj->arraycopy_dst(), "sanity");
370 #endif
371
372 _collecting = false;
373
374 _compile->print_method(PHASE_EA_AFTER_PROPAGATE_NSR, 4);
375 } // TracePhase t3("connectionGraph")
376
377 // 4. Optimize ideal graph based on EA information.
378 bool has_non_escaping_obj = (non_escaped_allocs_worklist.length() > 0);
379 if (has_non_escaping_obj) {
380 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist);
381 }
382
383 #ifndef PRODUCT
384 if (PrintEscapeAnalysis) {
385 dump(ptnodes_worklist); // Dump ConnectionGraph
386 }
387 #endif
388
389 #ifdef ASSERT
390 if (VerifyConnectionGraph) {
391 int alloc_length = alloc_worklist.length();
392 for (int next = 0; next < alloc_length; ++next) {
393 Node* n = alloc_worklist.at(next);
394 PointsToNode* ptn = ptnode_adr(n->_idx);
395 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity");
396 }
397 }
398
399 if (VerifyReduceAllocationMerges) {
400 for (uint i = 0; i < reducible_merges.size(); i++ ) {
401 Node* n = reducible_merges.at(i);
402 if (!can_reduce_phi(n->as_Phi())) {
403 TraceReduceAllocationMerges = true;
404 n->dump(2);
405 n->dump(-2);
406 assert(can_reduce_phi(n->as_Phi()), "Sanity: previous reducible Phi is no longer reducible before SUT.");
407 }
408 }
409 }
410 #endif
411
412 _compile->print_method(PHASE_EA_AFTER_GRAPH_OPTIMIZATION, 4);
413
414 // 5. Separate memory graph for scalar replaceable allcations.
415 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0);
416 if (has_scalar_replaceable_candidates && EliminateAllocations) {
417 assert(C->do_aliasing(), "Aliasing should be enabled");
418 // Now use the escape information to create unique types for
419 // scalar replaceable objects.
420 split_unique_types(alloc_worklist, arraycopy_worklist, mergemem_worklist, reducible_merges);
421 if (C->failing()) {
422 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
423 return false;
424 }
425
426 #ifdef ASSERT
427 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
428 tty->print("=== No allocations eliminated for ");
429 C->method()->print_short_name();
430 if (!EliminateAllocations) {
431 tty->print(" since EliminateAllocations is off ===");
432 } else if(!has_scalar_replaceable_candidates) {
433 tty->print(" since there are no scalar replaceable candidates ===");
434 }
435 tty->cr();
436 #endif
437 }
438
439 // 6. Expand flat accesses if the object does not escape. This adds nodes to
440 // the graph, so it has to be after split_unique_types. This expands atomic
441 // mismatched accesses (though encapsulated in LoadFlats and StoreFlats) into
442 // non-mismatched accesses, so it is better before reduce allocation merges.
443 if (has_non_escaping_obj) {
444 optimize_flat_accesses(sfn_worklist);
445 }
446
447 _compile->print_method(PHASE_EA_AFTER_SPLIT_UNIQUE_TYPES, 4);
448
449 // 7. Reduce allocation merges used as debug information. This is done after
450 // split_unique_types because the methods used to create SafePointScalarObject
451 // need to traverse the memory graph to find values for object fields. We also
452 // set to null the scalarized inputs of reducible Phis so that the Allocate
453 // that they point can be later scalar replaced.
454 bool delay = _igvn->delay_transform();
455 _igvn->set_delay_transform(true);
456 for (uint i = 0; i < reducible_merges.size(); i++) {
457 Node* n = reducible_merges.at(i);
458 if (n->outcnt() > 0) {
459 if (!reduce_phi_on_safepoints(n->as_Phi())) {
460 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
461 C->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
462 return false;
463 }
464
465 // Now we set the scalar replaceable inputs of ophi to null, which is
466 // the last piece that would prevent it from being scalar replaceable.
467 reset_scalar_replaceable_entries(n->as_Phi());
468 }
469 }
470 _igvn->set_delay_transform(delay);
471
472 // Annotate at safepoints if they have <= ArgEscape objects in their scope and at
473 // java calls if they pass ArgEscape objects as parameters.
474 if (has_non_escaping_obj &&
475 (C->env()->should_retain_local_variables() ||
476 C->env()->jvmti_can_get_owned_monitor_info() ||
477 C->env()->jvmti_can_walk_any_space() ||
478 DeoptimizeObjectsALot)) {
479 int sfn_length = sfn_worklist.length();
480 for (int next = 0; next < sfn_length; next++) {
481 SafePointNode* sfn = sfn_worklist.at(next);
482 sfn->set_has_ea_local_in_scope(has_ea_local_in_scope(sfn));
483 if (sfn->is_CallJava()) {
484 CallJavaNode* call = sfn->as_CallJava();
485 call->set_arg_escape(has_arg_escape(call));
486 }
487 }
488 }
489
490 _compile->print_method(PHASE_EA_AFTER_REDUCE_PHI_ON_SAFEPOINTS, 4);
491
492 NOT_PRODUCT(escape_state_statistics(java_objects_worklist);)
493 return has_non_escaping_obj;
494 }
495
496 // Check if it's profitable to reduce the Phi passed as parameter. Returns true
497 // if at least one scalar replaceable allocation participates in the merge.
498 bool ConnectionGraph::can_reduce_phi_check_inputs(PhiNode* ophi) const {
499 bool found_sr_allocate = false;
500
501 for (uint i = 1; i < ophi->req(); i++) {
502 JavaObjectNode* ptn = unique_java_object(ophi->in(i));
503 if (ptn != nullptr && ptn->scalar_replaceable()) {
504 AllocateNode* alloc = ptn->ideal_node()->as_Allocate();
505
506 // Don't handle arrays.
507 if (alloc->Opcode() != Op_Allocate) {
508 assert(alloc->Opcode() == Op_AllocateArray, "Unexpected type of allocation.");
509 continue;
510 }
511
512 if (PhaseMacroExpand::can_eliminate_allocation(_igvn, alloc, nullptr)) {
513 found_sr_allocate = true;
514 } else {
515 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("%dth input of Phi %d is SR but can't be eliminated.", i, ophi->_idx);)
516 ptn->set_scalar_replaceable(false);
517 }
518 }
519 }
520
521 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);)
522 return found_sr_allocate;
523 }
524
525 // We can reduce the Cmp if it's a comparison between the Phi and a constant.
526 // I require the 'other' input to be a constant so that I can move the Cmp
527 // around safely.
528 bool ConnectionGraph::can_reduce_cmp(PhiNode* phi, Node* cmp) const {
529 assert(cmp->Opcode() == Op_CmpP || cmp->Opcode() == Op_CmpN, "not expected node: %s", cmp->Name());
530 Node* left = cmp->in(1);
531 Node* right = cmp->in(2);
532
533 return (left == phi || right == phi) &&
534 (left->is_Con() || right->is_Con()) &&
535 cmp->outcnt() == 1;
536 }
537
538 // We are going to check if any of the SafePointScalarMerge entries
539 // in the SafePoint reference the Phi that we are checking.
540 bool ConnectionGraph::has_been_reduced(PhiNode* phi, SafePointNode* sfpt) const {
541 JVMState *jvms = sfpt->jvms();
542
543 for (uint i = jvms->debug_start(); i < jvms->debug_end(); i++) {
544 Node* sfpt_in = sfpt->in(i);
545 if (sfpt_in->is_SafePointScalarMerge()) {
546 SafePointScalarMergeNode* smerge = sfpt_in->as_SafePointScalarMerge();
547 Node* nsr_ptr = sfpt->in(smerge->merge_pointer_idx(jvms));
548 if (nsr_ptr == phi) {
549 return true;
550 }
551 }
552 }
553
554 return false;
555 }
556
557 // Check if we are able to untangle the merge. The following patterns are
558 // supported:
559 // - Phi -> SafePoints
560 // - Phi -> CmpP/N
561 // - Phi -> AddP -> Load
562 // - Phi -> CastPP -> SafePoints
563 // - Phi -> CastPP -> AddP -> Load
564 bool ConnectionGraph::can_reduce_check_users(Node* n, uint nesting) const {
565 assert((n->is_Phi() && nesting == 0) || (n->is_CastPP() && nesting > 0),
566 "invalid node class %s and nesting %d combination", n->Name(), nesting);
567 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
568 Node* use = n->fast_out(i);
569
570 if (use->is_SafePoint()) {
571 if (use->is_Call() && use->as_Call()->has_non_debug_use(n)) {
572 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. Call has non_debug_use().", n->_idx, _invocation);)
573 return false;
574 } else if (has_been_reduced(n->is_Phi() ? n->as_Phi() : n->as_CastPP()->in(1)->as_Phi(), use->as_SafePoint())) {
575 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. It has already been reduced.", n->_idx, _invocation);)
576 return false;
577 }
578 } else if (use->is_AddP()) {
579 Node* addp = use;
580 for (DUIterator_Fast jmax, j = addp->fast_outs(jmax); j < jmax; j++) {
581 Node* use_use = addp->fast_out(j);
582 const Type* load_type = _igvn->type(use_use);
583
584 if (!use_use->is_Load() || !use_use->as_Load()->can_split_through_phi_base(_igvn)) {
585 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. AddP user isn't a [splittable] Load(): %s", n->_idx, _invocation, use_use->Name());)
586 return false;
587 } else if (load_type->isa_narrowklass() || load_type->isa_klassptr()) {
588 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. [Narrow] Klass Load: %s", n->_idx, _invocation, use_use->Name());)
589 return false;
590 }
591 }
592 } else if (nesting > 0) {
593 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. Unsupported user %s at nesting level %d.", n->_idx, _invocation, use->Name(), nesting);)
594 return false;
595 } else if (use->is_CastPP()) {
596 const Type* cast_t = _igvn->type(use);
597 if (cast_t == nullptr || cast_t->make_ptr()->isa_instptr() == nullptr) {
598 #ifndef PRODUCT
599 if (TraceReduceAllocationMerges) {
600 tty->print_cr("Can NOT reduce Phi %d on invocation %d. CastPP is not to an instance.", n->_idx, _invocation);
601 use->dump();
602 }
603 #endif
604 return false;
605 }
606
607 if (!can_reduce_phi_at_castpp(n->as_Phi(), use->as_CastPP())) {
608 #ifdef ASSERT
609 if (TraceReduceAllocationMerges) {
610 tty->print_cr("Can NOT reduce Phi %d on invocation %d. CastPP %d doesn't have simple control.", n->_idx, _invocation, use->_idx);
611 n->dump(5);
612 }
613 #endif
614 return false;
615 }
616
617 if (!can_reduce_check_users(use, nesting+1)) {
618 return false;
619 }
620 } else if (use->Opcode() == Op_CmpP || use->Opcode() == Op_CmpN) {
621 if (!can_reduce_cmp(n->as_Phi(), use)) {
622 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. CmpP/N %d isn't reducible.", n->_idx, _invocation, use->_idx);)
623 return false;
624 }
625 } else {
626 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Can NOT reduce Phi %d on invocation %d. One of the uses is: %d %s", n->_idx, _invocation, use->_idx, use->Name());)
627 return false;
628 }
629 }
630
631 return true;
632 }
633
634 // Returns true if the CastPP's control is simple enough to reduce the Phi:
635 // 1) no control,
636 // 2) control is the same Region as the Phi, or
637 // 3) an IfTrue/IfFalse coming from an CmpP/N between the phi and a constant.
638 bool ConnectionGraph::can_reduce_phi_at_castpp(PhiNode* phi, CastPPNode* castpp) const {
639 if (castpp->in(0) == nullptr || castpp->in(0) == phi->in(0)) {
640 return true;
641 }
642 // If it's not a trivial control then we check if we can reduce the
643 // CmpP/N used by the If controlling the cast.
644 if (!(castpp->in(0)->is_IfTrue() || castpp->in(0)->is_IfFalse())) {
645 return false; // Only If control is considered
646 } else {
647 Node* iff = castpp->in(0)->in(0);
648 // We may have an OpaqueConstantBool node between If and Bool nodes. But we could also have a sub class of IfNode,
649 // for example, an OuterStripMinedLoopEnd or a Parse Predicate. Bail out in all these cases.
650 if (iff->Opcode() == Op_If && iff->in(1)->is_Bool() && iff->in(1)->in(1)->is_Cmp()) {
651 Node* iff_cmp = iff->in(1)->in(1);
652 int opc = iff_cmp->Opcode();
653 if ((opc == Op_CmpP || opc == Op_CmpN) && can_reduce_cmp(phi, iff_cmp)) {
654 return true;
655 }
656 }
657 }
658 return false;
659 }
660
661 // Returns true if: 1) It's profitable to reduce the merge, and 2) The Phi is
662 // only used in some certain code shapes. Check comments in
663 // 'can_reduce_phi_inputs' and 'can_reduce_phi_users' for more
664 // details.
665 bool ConnectionGraph::can_reduce_phi(PhiNode* ophi) const {
666 // If there was an error attempting to reduce allocation merges for this
667 // method we might have disabled the compilation and be retrying with RAM
668 // disabled.
669 if (!_compile->do_reduce_allocation_merges() || ophi->region()->Opcode() != Op_Region) {
670 return false;
671 }
672
673 const Type* phi_t = _igvn->type(ophi);
674 if (phi_t == nullptr ||
675 phi_t->make_ptr() == nullptr ||
676 phi_t->make_ptr()->isa_aryptr() != nullptr) {
677 return false;
678 }
679
680 if (!can_reduce_phi_check_inputs(ophi) || !can_reduce_check_users(ophi, /* nesting: */ 0)) {
681 return false;
682 }
683
684 NOT_PRODUCT(if (TraceReduceAllocationMerges) { tty->print_cr("Can reduce Phi %d during invocation %d: ", ophi->_idx, _invocation); })
685 return true;
686 }
687
688 // This method will return a CmpP/N that we need to use on the If controlling a
689 // CastPP after it was split. This method is only called on bases that are
690 // nullable therefore we always need a controlling if for the splitted CastPP.
691 //
692 // 'curr_ctrl' is the control of the CastPP that we want to split through phi.
693 // If the CastPP currently doesn't have a control then the CmpP/N will be
694 // against the null constant, otherwise it will be against the constant input of
695 // the existing CmpP/N. It's guaranteed that there will be a CmpP/N in the later
696 // case because we have constraints on it and because the CastPP has a control
697 // input.
698 Node* ConnectionGraph::specialize_cmp(Node* base, Node* curr_ctrl) {
699 const Type* t = base->bottom_type();
700 Node* con = nullptr;
701
702 if (curr_ctrl == nullptr || curr_ctrl->is_Region()) {
703 con = _igvn->zerocon(t->basic_type());
704 } else {
705 // can_reduce_check_users() verified graph: true/false -> if -> bool -> cmp
706 assert(curr_ctrl->in(0)->Opcode() == Op_If, "unexpected node %s", curr_ctrl->in(0)->Name());
707 Node* bol = curr_ctrl->in(0)->in(1);
708 assert(bol->is_Bool(), "unexpected node %s", bol->Name());
709 Node* curr_cmp = bol->in(1);
710 assert(curr_cmp->Opcode() == Op_CmpP || curr_cmp->Opcode() == Op_CmpN, "unexpected node %s", curr_cmp->Name());
711 con = curr_cmp->in(1)->is_Con() ? curr_cmp->in(1) : curr_cmp->in(2);
712 }
713
714 return CmpNode::make(base, con, t->basic_type());
715 }
716
717 // This method 'specializes' the CastPP passed as parameter to the base passed
718 // as parameter. Note that the existing CastPP input is a Phi. "Specialize"
719 // means that the CastPP now will be specific for a given base instead of a Phi.
720 // An If-Then-Else-Region block is inserted to control the CastPP. The control
721 // of the CastPP is a copy of the current one (if there is one) or a check
722 // against null.
723 //
724 // Before:
725 //
726 // C1 C2 ... Cn
727 // \ | /
728 // \ | /
729 // \ | /
730 // \ | /
731 // \ | /
732 // \ | /
733 // \|/
734 // Region B1 B2 ... Bn
735 // | \ | /
736 // | \ | /
737 // | \ | /
738 // | \ | /
739 // | \ | /
740 // | \ | /
741 // ---------------> Phi
742 // |
743 // X |
744 // | |
745 // | |
746 // ------> CastPP
747 //
748 // After (only partial illustration; base = B2, current_control = C2):
749 //
750 // C2
751 // |
752 // If
753 // / \
754 // / \
755 // T F
756 // /\ /
757 // / \ /
758 // / \ /
759 // C1 CastPP Reg Cn
760 // | | |
761 // | | |
762 // | | |
763 // -------------- | ----------
764 // | | |
765 // Region
766 //
767 Node* ConnectionGraph::specialize_castpp(Node* castpp, Node* base, Node* current_control) {
768 Node* control_successor = current_control->unique_ctrl_out();
769 Node* cmp = _igvn->transform(specialize_cmp(base, castpp->in(0)));
770 Node* bol = _igvn->transform(new BoolNode(cmp, BoolTest::ne));
771 IfNode* if_ne = _igvn->transform(new IfNode(current_control, bol, PROB_MIN, COUNT_UNKNOWN))->as_If();
772 Node* not_eq_control = _igvn->transform(new IfTrueNode(if_ne));
773 Node* yes_eq_control = _igvn->transform(new IfFalseNode(if_ne));
774 Node* end_region = _igvn->transform(new RegionNode(3));
775
776 // Insert the new if-else-region block into the graph
777 end_region->set_req(1, not_eq_control);
778 end_region->set_req(2, yes_eq_control);
779 control_successor->replace_edge(current_control, end_region, _igvn);
780
781 _igvn->_worklist.push(current_control);
782 _igvn->_worklist.push(control_successor);
783
784 return _igvn->transform(ConstraintCastNode::make_cast_for_type(not_eq_control, base, _igvn->type(castpp), ConstraintCastNode::DependencyType::NonFloatingNonNarrowing, nullptr));
785 }
786
787 Node* ConnectionGraph::split_castpp_load_through_phi(Node* curr_addp, Node* curr_load, Node* region, GrowableArray<Node*>* bases_for_loads, GrowableArray<Node *> &alloc_worklist) {
788 const Type* load_type = _igvn->type(curr_load);
789 Node* nsr_value = _igvn->zerocon(load_type->basic_type());
790 Node* memory = curr_load->in(MemNode::Memory);
791
792 // The data_phi merging the loads needs to be nullable if
793 // we are loading pointers.
794 if (load_type->make_ptr() != nullptr) {
795 if (load_type->isa_narrowoop()) {
796 load_type = load_type->meet(TypeNarrowOop::NULL_PTR);
797 } else if (load_type->isa_ptr()) {
798 load_type = load_type->meet(TypePtr::NULL_PTR);
799 } else {
800 assert(false, "Unexpected load ptr type.");
801 }
802 }
803
804 Node* data_phi = PhiNode::make(region, nsr_value, load_type);
805
806 for (int i = 1; i < bases_for_loads->length(); i++) {
807 Node* base = bases_for_loads->at(i);
808 Node* cmp_region = nullptr;
809 if (base != nullptr) {
810 if (base->is_CFG()) { // means that we added a CastPP as child of this CFG node
811 cmp_region = base->unique_ctrl_out_or_null();
812 assert(cmp_region != nullptr, "There should be.");
813 base = base->find_out_with(Op_CastPP);
814 }
815
816 Node* addr = _igvn->transform(AddPNode::make_with_base(base, curr_addp->in(AddPNode::Offset)));
817 Node* mem = (memory->is_Phi() && (memory->in(0) == region)) ? memory->in(i) : memory;
818 Node* load = curr_load->clone();
819 load->set_req(0, nullptr);
820 load->set_req(1, mem);
821 load->set_req(2, addr);
822
823 if (cmp_region != nullptr) { // see comment on previous if
824 Node* intermediate_phi = PhiNode::make(cmp_region, nsr_value, load_type);
825 intermediate_phi->set_req(1, _igvn->transform(load));
826 load = intermediate_phi;
827 }
828
829 data_phi->set_req(i, _igvn->transform(load));
830 } else {
831 // Just use the default, which is already in phi
832 }
833 }
834
835 // Takes care of updating CG and split_unique_types worklists due
836 // to cloned AddP->Load.
837 updates_after_load_split(data_phi, curr_load, alloc_worklist);
838
839 return _igvn->transform(data_phi);
840 }
841
842 // This method only reduces CastPP fields loads; SafePoints are handled
843 // separately. The idea here is basically to clone the CastPP and place copies
844 // on each input of the Phi, including non-scalar replaceable inputs.
845 // Experimentation shows that the resulting IR graph is simpler that way than if
846 // we just split the cast through scalar-replaceable inputs.
847 //
848 // The reduction process requires that CastPP's control be one of:
849 // 1) no control,
850 // 2) the same region as Ophi, or
851 // 3) an IfTrue/IfFalse coming from an CmpP/N between Ophi and a constant.
852 //
853 // After splitting the CastPP we'll put it under an If-Then-Else-Region control
854 // flow. If the CastPP originally had an IfTrue/False control input then we'll
855 // use a similar CmpP/N to control the new If-Then-Else-Region. Otherwise, we'll
856 // juse use a CmpP/N against the null constant.
857 //
858 // The If-Then-Else-Region isn't always needed. For instance, if input to
859 // splitted cast was not nullable (or if it was the null constant) then we don't
860 // need (shouldn't) use a CastPP at all.
861 //
862 // After the casts are splitted we'll split the AddP->Loads through the Phi and
863 // connect them to the just split CastPPs.
864 //
865 // Before (CastPP control is same as Phi):
866 //
867 // Region Allocate Null Call
868 // | \ | /
869 // | \ | /
870 // | \ | /
871 // | \ | /
872 // | \ | /
873 // | \ | /
874 // ------------------> Phi # Oop Phi
875 // | |
876 // | |
877 // | |
878 // | |
879 // ----------------> CastPP
880 // |
881 // AddP
882 // |
883 // Load
884 //
885 // After (Very much simplified):
886 //
887 // Call Null
888 // \ /
889 // CmpP
890 // |
891 // Bool#NE
892 // |
893 // If
894 // / \
895 // T F
896 // / \ /
897 // / R
898 // CastPP |
899 // | |
900 // AddP |
901 // | |
902 // Load |
903 // \ | 0
904 // Allocate \ | /
905 // \ \ | /
906 // AddP Phi
907 // \ /
908 // Load /
909 // \ 0 /
910 // \ | /
911 // \|/
912 // Phi # "Field" Phi
913 //
914 void ConnectionGraph::reduce_phi_on_castpp_field_load(CastPPNode* curr_castpp, GrowableArray<Node*> &alloc_worklist) {
915 PhiNode* ophi = curr_castpp->in(1)->as_Phi();
916 precond(can_reduce_phi_at_castpp(ophi, curr_castpp));
917
918 // Identify which base should be used for AddP->Load later when spliting the
919 // CastPP->Loads through ophi. Three kind of values may be stored in this
920 // array, depending on the nullability status of the corresponding input in
921 // ophi.
922 //
923 // - nullptr: Meaning that the base is actually the null constant and therefore
924 // we won't try to load from it.
925 //
926 // - CFG Node: Meaning that the base is a CastPP that was specialized for
927 // this input of Ophi. I.e., we added an If->Then->Else-Region
928 // that will 'activate' the CastPp only when the input is not Null.
929 //
930 // - Other Node: Meaning that the base is not nullable and therefore we'll try
931 // to load directly from it.
932 GrowableArray<Node*> bases_for_loads(ophi->req(), ophi->req(), nullptr);
933
934 for (uint i = 1; i < ophi->req(); i++) {
935 Node* base = ophi->in(i);
936 const Type* base_t = _igvn->type(base);
937
938 if (base_t->maybe_null()) {
939 if (base->is_Con()) {
940 // Nothing todo as bases_for_loads[i] is already null
941 } else {
942 Node* new_castpp = specialize_castpp(curr_castpp, base, ophi->in(0)->in(i));
943 bases_for_loads.at_put(i, new_castpp->in(0)); // Use the ctrl of the new node just as a flag
944 }
945 } else {
946 bases_for_loads.at_put(i, base);
947 }
948 }
949
950 // Now let's split the CastPP->Loads through the Phi
951 for (int i = curr_castpp->outcnt()-1; i >= 0;) {
952 Node* use = curr_castpp->raw_out(i);
953 if (use->is_AddP()) {
954 for (int j = use->outcnt()-1; j >= 0;) {
955 Node* use_use = use->raw_out(j);
956 assert(use_use->is_Load(), "Expected this to be a Load node.");
957
958 // We can't make an unconditional load from a nullable input. The
959 // 'split_castpp_load_through_phi` method will add an
960 // 'If-Then-Else-Region` around nullable bases and only load from them
961 // when the input is not null.
962 Node* phi = split_castpp_load_through_phi(use, use_use, ophi->in(0), &bases_for_loads, alloc_worklist);
963 _igvn->replace_node(use_use, phi);
964
965 --j;
966 j = MIN2(j, (int)use->outcnt()-1);
967 }
968
969 _igvn->remove_dead_node(use, PhaseIterGVN::NodeOrigin::Graph);
970 }
971 --i;
972 i = MIN2(i, (int)curr_castpp->outcnt()-1);
973 }
974 }
975
976 // This method split a given CmpP/N through the Phi used in one of its inputs.
977 // As a result we convert a comparison with a pointer to a comparison with an
978 // integer.
979 // The only requirement is that one of the inputs of the CmpP/N must be a Phi
980 // while the other must be a constant.
981 // The splitting process is basically just cloning the CmpP/N above the input
982 // Phi. However, some (most) of the cloned CmpP/Ns won't be requred because we
983 // can prove at compile time the result of the comparison.
984 //
985 // Before:
986 //
987 // in1 in2 ... inN
988 // \ | /
989 // \ | /
990 // \ | /
991 // \ | /
992 // \ | /
993 // \ | /
994 // Phi
995 // | Other
996 // | /
997 // | /
998 // | /
999 // CmpP/N
1000 //
1001 // After:
1002 //
1003 // in1 Other in2 Other inN Other
1004 // | | | | | |
1005 // \ | | | | |
1006 // \ / | / | /
1007 // CmpP/N CmpP/N CmpP/N
1008 // Bool Bool Bool
1009 // \ | /
1010 // \ | /
1011 // \ | /
1012 // \ | /
1013 // \ | /
1014 // \ | /
1015 // \ | /
1016 // \ | /
1017 // Phi
1018 // |
1019 // | Zero
1020 // | /
1021 // | /
1022 // | /
1023 // CmpI
1024 //
1025 //
1026 void ConnectionGraph::reduce_phi_on_cmp(Node* cmp) {
1027 Node* ophi = cmp->in(1)->is_Con() ? cmp->in(2) : cmp->in(1);
1028 assert(ophi->is_Phi(), "Expected this to be a Phi node.");
1029
1030 Node* other = cmp->in(1)->is_Con() ? cmp->in(1) : cmp->in(2);
1031 Node* zero = _igvn->intcon(0);
1032 Node* one = _igvn->intcon(1);
1033 BoolTest::mask mask = cmp->unique_out()->as_Bool()->_test._test;
1034
1035 // This Phi will merge the result of the Cmps split through the Phi
1036 Node* res_phi = PhiNode::make(ophi->in(0), zero, TypeInt::INT);
1037
1038 for (uint i=1; i<ophi->req(); i++) {
1039 Node* ophi_input = ophi->in(i);
1040 Node* res_phi_input = nullptr;
1041
1042 const TypeInt* tcmp = optimize_ptr_compare(ophi_input, other);
1043 if (tcmp->singleton()) {
1044 if ((mask == BoolTest::mask::eq && tcmp == TypeInt::CC_EQ) ||
1045 (mask == BoolTest::mask::ne && tcmp == TypeInt::CC_GT)) {
1046 res_phi_input = one;
1047 } else {
1048 res_phi_input = zero;
1049 }
1050 } else {
1051 Node* ncmp = _igvn->transform(cmp->clone());
1052 ncmp->set_req(1, ophi_input);
1053 ncmp->set_req(2, other);
1054 Node* bol = _igvn->transform(new BoolNode(ncmp, mask));
1055 res_phi_input = bol->as_Bool()->as_int_value(_igvn);
1056 }
1057
1058 res_phi->set_req(i, res_phi_input);
1059 }
1060
1061 // This CMP always compares whether the output of "res_phi" is TRUE as far as the "mask".
1062 Node* new_cmp = _igvn->transform(new CmpINode(_igvn->transform(res_phi), (mask == BoolTest::mask::eq) ? one : zero));
1063 _igvn->replace_node(cmp, new_cmp);
1064 }
1065
1066 // Push the newly created AddP on alloc_worklist and patch
1067 // the connection graph. Note that the changes in the CG below
1068 // won't affect the ES of objects since the new nodes have the
1069 // same status as the old ones.
1070 void ConnectionGraph::updates_after_load_split(Node* data_phi, Node* previous_load, GrowableArray<Node *> &alloc_worklist) {
1071 assert(data_phi != nullptr, "Output of split_through_phi is null.");
1072 assert(data_phi != previous_load, "Output of split_through_phi is same as input.");
1073 assert(data_phi->is_Phi(), "Output of split_through_phi isn't a Phi.");
1074
1075 if (data_phi == nullptr || !data_phi->is_Phi()) {
1076 // Make this a retry?
1077 return ;
1078 }
1079
1080 Node* previous_addp = previous_load->in(MemNode::Address);
1081 FieldNode* fn = ptnode_adr(previous_addp->_idx)->as_Field();
1082 for (uint i = 1; i < data_phi->req(); i++) {
1083 Node* new_load = data_phi->in(i);
1084
1085 if (new_load->is_Phi()) {
1086 // new_load is currently the "intermediate_phi" from an specialized
1087 // CastPP.
1088 new_load = new_load->in(1);
1089 }
1090
1091 // "new_load" might actually be a constant, parameter, etc.
1092 if (new_load->is_Load()) {
1093 Node* new_addp = new_load->in(MemNode::Address);
1094
1095 // If new_load is a Load but not from an AddP, it means that the load is folded into another
1096 // load. And since this load is not from a field, we cannot create a unique type for it.
1097 // For example:
1098 //
1099 // if (b) {
1100 // Holder h1 = new Holder();
1101 // Object o = ...;
1102 // h.o = o.getClass();
1103 // } else {
1104 // Holder h2 = ...;
1105 // }
1106 // Holder h = Phi(h1, h2);
1107 // Object r = h.o;
1108 //
1109 // Then, splitting r through the merge point results in:
1110 //
1111 // if (b) {
1112 // Holder h1 = new Holder();
1113 // Object o = ...;
1114 // h.o = o.getClass();
1115 // Object o1 = h.o;
1116 // } else {
1117 // Holder h2 = ...;
1118 // Object o2 = h2.o;
1119 // }
1120 // Object r = Phi(o1, o2);
1121 //
1122 // In this case, o1 is folded to o.getClass() which is a Load but not from an AddP, but from
1123 // an OopHandle that is loaded from the Klass of o.
1124 if (!new_addp->is_AddP()) {
1125 continue;
1126 }
1127 Node* base = get_addp_base(new_addp);
1128
1129 // The base might not be something that we can create an unique
1130 // type for. If that's the case we are done with that input.
1131 PointsToNode* jobj_ptn = unique_java_object(base);
1132 if (jobj_ptn == nullptr || !jobj_ptn->scalar_replaceable()) {
1133 continue;
1134 }
1135
1136 // Push to alloc_worklist since the base has an unique_type
1137 alloc_worklist.append_if_missing(new_addp);
1138
1139 // Now let's add the node to the connection graph
1140 _nodes.at_grow(new_addp->_idx, nullptr);
1141 add_field(new_addp, fn->escape_state(), fn->offset());
1142 add_base(ptnode_adr(new_addp->_idx)->as_Field(), ptnode_adr(base->_idx));
1143
1144 // If the load doesn't load an object then it won't be
1145 // part of the connection graph
1146 PointsToNode* curr_load_ptn = ptnode_adr(previous_load->_idx);
1147 if (curr_load_ptn != nullptr) {
1148 _nodes.at_grow(new_load->_idx, nullptr);
1149 add_local_var(new_load, curr_load_ptn->escape_state());
1150 add_edge(ptnode_adr(new_load->_idx), ptnode_adr(new_addp->_idx)->as_Field());
1151 }
1152 }
1153 }
1154 }
1155
1156 void ConnectionGraph::reduce_phi_on_field_access(Node* previous_addp, GrowableArray<Node *> &alloc_worklist) {
1157 // We'll pass this to 'split_through_phi' so that it'll do the split even
1158 // though the load doesn't have an unique instance type.
1159 bool ignore_missing_instance_id = true;
1160
1161 // All AddPs are present in the connection graph
1162 FieldNode* fn = ptnode_adr(previous_addp->_idx)->as_Field();
1163
1164 // Iterate over AddP looking for a Load
1165 for (int k = previous_addp->outcnt()-1; k >= 0;) {
1166 Node* previous_load = previous_addp->raw_out(k);
1167 if (previous_load->is_Load()) {
1168 Node* data_phi = previous_load->as_Load()->split_through_phi(_igvn, ignore_missing_instance_id);
1169
1170 // Takes care of updating CG and split_unique_types worklists due to cloned
1171 // AddP->Load.
1172 updates_after_load_split(data_phi, previous_load, alloc_worklist);
1173
1174 _igvn->replace_node(previous_load, data_phi);
1175 }
1176 --k;
1177 k = MIN2(k, (int)previous_addp->outcnt()-1);
1178 }
1179
1180 // Remove the old AddP from the processing list because it's dead now
1181 assert(previous_addp->outcnt() == 0, "AddP should be dead now.");
1182 alloc_worklist.remove_if_existing(previous_addp);
1183 }
1184
1185 // Create a 'selector' Phi based on the inputs of 'ophi'. If index 'i' of the
1186 // selector is:
1187 // -> a '-1' constant, the i'th input of the original Phi is NSR.
1188 // -> a 'x' constant >=0, the i'th input of of original Phi will be SR and
1189 // the info about the scalarized object will be at index x of ObjectMergeValue::possible_objects
1190 PhiNode* ConnectionGraph::create_selector(PhiNode* ophi) const {
1191 Node* minus_one = _igvn->register_new_node_with_optimizer(ConINode::make(-1));
1192 Node* selector = _igvn->register_new_node_with_optimizer(PhiNode::make(ophi->region(), minus_one, TypeInt::INT));
1193 uint number_of_sr_objects = 0;
1194 for (uint i = 1; i < ophi->req(); i++) {
1195 Node* base = ophi->in(i);
1196 JavaObjectNode* ptn = unique_java_object(base);
1197
1198 if (ptn != nullptr && ptn->scalar_replaceable()) {
1199 Node* sr_obj_idx = _igvn->register_new_node_with_optimizer(ConINode::make(number_of_sr_objects));
1200 selector->set_req(i, sr_obj_idx);
1201 number_of_sr_objects++;
1202 }
1203 }
1204
1205 return selector->as_Phi();
1206 }
1207
1208 // Returns true if the AddP node 'n' has at least one base that is a reducible
1209 // merge. If the base is a CastPP/CheckCastPP then the input of the cast is
1210 // checked instead.
1211 bool ConnectionGraph::has_reducible_merge_base(AddPNode* n, Unique_Node_List &reducible_merges) {
1212 PointsToNode* ptn = ptnode_adr(n->_idx);
1213 if (ptn == nullptr || !ptn->is_Field() || ptn->as_Field()->base_count() < 2) {
1214 return false;
1215 }
1216
1217 for (BaseIterator i(ptn->as_Field()); i.has_next(); i.next()) {
1218 Node* base = i.get()->ideal_node();
1219
1220 if (reducible_merges.member(base)) {
1221 return true;
1222 }
1223
1224 if (base->is_CastPP() || base->is_CheckCastPP()) {
1225 base = base->in(1);
1226 if (reducible_merges.member(base)) {
1227 return true;
1228 }
1229 }
1230 }
1231
1232 return false;
1233 }
1234
1235 // This method will call its helper method to reduce SafePoint nodes that use
1236 // 'ophi' or a casted version of 'ophi'. All SafePoint nodes using the same
1237 // "version" of Phi use the same debug information (regarding the Phi).
1238 // Therefore, I collect all safepoints and patch them all at once.
1239 //
1240 // The safepoints using the Phi node have to be processed before safepoints of
1241 // CastPP nodes. The reason is, when reducing a CastPP we add a reference (the
1242 // NSR merge pointer) to the input of the CastPP (i.e., the Phi) in the
1243 // safepoint. If we process CastPP's safepoints before Phi's safepoints the
1244 // algorithm that process Phi's safepoints will think that the added Phi
1245 // reference is a regular reference.
1246 bool ConnectionGraph::reduce_phi_on_safepoints(PhiNode* ophi) {
1247 PhiNode* selector = create_selector(ophi);
1248 Unique_Node_List safepoints;
1249 Unique_Node_List casts;
1250
1251 // Just collect the users of the Phis for later processing
1252 // in the needed order.
1253 for (uint i = 0; i < ophi->outcnt(); i++) {
1254 Node* use = ophi->raw_out(i);
1255 if (use->is_SafePoint()) {
1256 safepoints.push(use);
1257 } else if (use->is_CastPP()) {
1258 casts.push(use);
1259 } else {
1260 assert(use->outcnt() == 0, "Only CastPP & SafePoint users should be left.");
1261 }
1262 }
1263
1264 // Need to process safepoints using the Phi first
1265 if (!reduce_phi_on_safepoints_helper(ophi, nullptr, selector, safepoints)) {
1266 return false;
1267 }
1268
1269 // Now process CastPP->safepoints
1270 for (uint i = 0; i < casts.size(); i++) {
1271 Node* cast = casts.at(i);
1272 Unique_Node_List cast_sfpts;
1273
1274 for (DUIterator_Fast jmax, j = cast->fast_outs(jmax); j < jmax; j++) {
1275 Node* use_use = cast->fast_out(j);
1276 if (use_use->is_SafePoint()) {
1277 cast_sfpts.push(use_use);
1278 } else {
1279 assert(use_use->outcnt() == 0, "Only SafePoint users should be left.");
1280 }
1281 }
1282
1283 if (!reduce_phi_on_safepoints_helper(ophi, cast, selector, cast_sfpts)) {
1284 return false;
1285 }
1286 }
1287
1288 return true;
1289 }
1290
1291 // This method will create a SafePointScalarMERGEnode for each SafePoint in
1292 // 'safepoints'. It then will iterate on the inputs of 'ophi' and create a
1293 // SafePointScalarObjectNode for each scalar replaceable input. Each
1294 // SafePointScalarMergeNode may describe multiple scalar replaced objects -
1295 // check detailed description in SafePointScalarMergeNode class header.
1296 bool ConnectionGraph::reduce_phi_on_safepoints_helper(Node* ophi, Node* cast, Node* selector, Unique_Node_List& safepoints) {
1297 PhaseMacroExpand mexp(*_igvn);
1298 Node* original_sfpt_parent = cast != nullptr ? cast : ophi;
1299 const TypeOopPtr* merge_t = _igvn->type(original_sfpt_parent)->make_oopptr();
1300
1301 Node* nsr_merge_pointer = ophi;
1302 if (cast != nullptr) {
1303 const Type* new_t = merge_t->meet(TypePtr::NULL_PTR);
1304 nsr_merge_pointer = _igvn->transform(ConstraintCastNode::make_cast_for_type(cast->in(0), cast->in(1), new_t, ConstraintCastNode::DependencyType::FloatingNarrowing, nullptr));
1305 }
1306
1307 for (uint spi = 0; spi < safepoints.size(); spi++) {
1308 SafePointNode* sfpt = safepoints.at(spi)->as_SafePoint();
1309
1310 SafePointNode::NodeEdgeTempStorage non_debug_edges_worklist(*_igvn);
1311
1312 // All sfpt inputs are implicitly included into debug info during the scalarization process below.
1313 // Keep non-debug inputs separately, so they stay non-debug.
1314 sfpt->remove_non_debug_edges(non_debug_edges_worklist);
1315
1316 JVMState* jvms = sfpt->jvms();
1317 uint merge_idx = (sfpt->req() - jvms->scloff());
1318 int debug_start = jvms->debug_start();
1319
1320 SafePointScalarMergeNode* smerge = new SafePointScalarMergeNode(merge_t, merge_idx);
1321 smerge->init_req(0, _compile->root());
1322 _igvn->register_new_node_with_optimizer(smerge);
1323
1324 assert(sfpt->jvms()->endoff() == sfpt->req(), "no extra edges past debug info allowed");
1325
1326 // The next two inputs are:
1327 // (1) A copy of the original pointer to NSR objects.
1328 // (2) A selector, used to decide if we need to rematerialize an object
1329 // or use the pointer to a NSR object.
1330 // See more details of these fields in the declaration of SafePointScalarMergeNode.
1331 // It is safe to include them into debug info straight away since create_scalarized_object_description()
1332 // will include all newly added inputs into debug info anyway.
1333 sfpt->add_req(nsr_merge_pointer);
1334 sfpt->add_req(selector);
1335 sfpt->jvms()->set_endoff(sfpt->req());
1336
1337 for (uint i = 1; i < ophi->req(); i++) {
1338 Node* base = ophi->in(i);
1339 JavaObjectNode* ptn = unique_java_object(base);
1340
1341 // If the base is not scalar replaceable we don't need to register information about
1342 // it at this time.
1343 if (ptn == nullptr || !ptn->scalar_replaceable()) {
1344 continue;
1345 }
1346
1347 AllocateNode* alloc = ptn->ideal_node()->as_Allocate();
1348 Unique_Node_List value_worklist;
1349 #ifdef ASSERT
1350 const Type* res_type = alloc->result_cast()->bottom_type();
1351 if (res_type->is_inlinetypeptr() && !Compile::current()->has_circular_inline_type()) {
1352 assert(!ophi->as_Phi()->can_push_inline_types_down(_igvn), "missed earlier scalarization opportunity");
1353 }
1354 #endif
1355 SafePointScalarObjectNode* sobj = mexp.create_scalarized_object_description(alloc, sfpt, &value_worklist);
1356 if (sobj == nullptr) {
1357 _compile->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
1358 sfpt->restore_non_debug_edges(non_debug_edges_worklist);
1359 return false; // non-recoverable failure; recompile
1360 }
1361
1362 // Now make a pass over the debug information replacing any references
1363 // to the allocated object with "sobj"
1364 Node* ccpp = alloc->result_cast();
1365 sfpt->replace_edges_in_range(ccpp, sobj, debug_start, jvms->debug_end(), _igvn);
1366 non_debug_edges_worklist.remove_edge_if_present(ccpp); // drop scalarized input from non-debug info
1367
1368 // Register the scalarized object as a candidate for reallocation
1369 smerge->add_req(sobj);
1370
1371 // Scalarize inline types that were added to the safepoint.
1372 // Don't allow linking a constant oop (if available) for flat array elements
1373 // because Deoptimization::reassign_flat_array_elements needs field values.
1374 const bool allow_oop = !merge_t->is_flat();
1375 for (uint j = 0; j < value_worklist.size(); ++j) {
1376 InlineTypeNode* vt = value_worklist.at(j)->as_InlineType();
1377 vt->make_scalar_in_safepoints(_igvn, allow_oop);
1378 }
1379 }
1380
1381 // Replaces debug information references to "original_sfpt_parent" in "sfpt" with references to "smerge"
1382 sfpt->replace_edges_in_range(original_sfpt_parent, smerge, debug_start, jvms->debug_end(), _igvn);
1383 non_debug_edges_worklist.remove_edge_if_present(original_sfpt_parent); // drop scalarized input from non-debug info
1384
1385 // The call to 'replace_edges_in_range' above might have removed the
1386 // reference to ophi that we need at _merge_pointer_idx. The line below make
1387 // sure the reference is maintained.
1388 sfpt->set_req(smerge->merge_pointer_idx(jvms), nsr_merge_pointer);
1389
1390 sfpt->restore_non_debug_edges(non_debug_edges_worklist);
1391
1392 _igvn->_worklist.push(sfpt);
1393 }
1394
1395 return true;
1396 }
1397
1398 void ConnectionGraph::reduce_phi(PhiNode* ophi, GrowableArray<Node*> &alloc_worklist) {
1399 bool delay = _igvn->delay_transform();
1400 _igvn->set_delay_transform(true);
1401 _igvn->hash_delete(ophi);
1402
1403 // Copying all users first because some will be removed and others won't.
1404 // Ophi also may acquire some new users as part of Cast reduction.
1405 // CastPPs also need to be processed before CmpPs.
1406 Unique_Node_List castpps;
1407 Unique_Node_List others;
1408 for (DUIterator_Fast imax, i = ophi->fast_outs(imax); i < imax; i++) {
1409 Node* use = ophi->fast_out(i);
1410
1411 if (use->is_CastPP()) {
1412 castpps.push(use);
1413 } else if (use->is_AddP() || use->is_Cmp()) {
1414 others.push(use);
1415 } else {
1416 // Safepoints to be processed later; other users aren't expected here
1417 assert(use->is_SafePoint(), "Unexpected user of reducible Phi %d -> %d:%s:%d", ophi->_idx, use->_idx, use->Name(), use->outcnt());
1418 }
1419 }
1420
1421 _compile->print_method(PHASE_EA_BEFORE_PHI_REDUCTION, 5, ophi);
1422
1423 // CastPPs need to be processed before Cmps because during the process of
1424 // splitting CastPPs we make reference to the inputs of the Cmp that is used
1425 // by the If controlling the CastPP.
1426 for (uint i = 0; i < castpps.size(); i++) {
1427 reduce_phi_on_castpp_field_load(castpps.at(i)->as_CastPP(), alloc_worklist);
1428 _compile->print_method(PHASE_EA_AFTER_PHI_CASTPP_REDUCTION, 6, castpps.at(i));
1429 }
1430
1431 for (uint i = 0; i < others.size(); i++) {
1432 Node* use = others.at(i);
1433
1434 if (use->is_AddP()) {
1435 reduce_phi_on_field_access(use, alloc_worklist);
1436 _compile->print_method(PHASE_EA_AFTER_PHI_ADDP_REDUCTION, 6, use);
1437 } else if(use->is_Cmp()) {
1438 reduce_phi_on_cmp(use);
1439 _compile->print_method(PHASE_EA_AFTER_PHI_CMP_REDUCTION, 6, use);
1440 }
1441 }
1442
1443 _igvn->set_delay_transform(delay);
1444 }
1445
1446 void ConnectionGraph::reset_scalar_replaceable_entries(PhiNode* ophi) {
1447 Node* null_ptr = _igvn->makecon(TypePtr::NULL_PTR);
1448 const TypeOopPtr* merge_t = _igvn->type(ophi)->make_oopptr();
1449 const Type* new_t = merge_t->meet(TypePtr::NULL_PTR);
1450 Node* new_phi = _igvn->register_new_node_with_optimizer(PhiNode::make(ophi->region(), null_ptr, new_t));
1451
1452 for (uint i = 1; i < ophi->req(); i++) {
1453 Node* base = ophi->in(i);
1454 JavaObjectNode* ptn = unique_java_object(base);
1455
1456 if (ptn != nullptr && ptn->scalar_replaceable()) {
1457 new_phi->set_req(i, null_ptr);
1458 } else {
1459 new_phi->set_req(i, ophi->in(i));
1460 }
1461 }
1462
1463 for (int i = ophi->outcnt()-1; i >= 0;) {
1464 Node* out = ophi->raw_out(i);
1465
1466 if (out->is_ConstraintCast()) {
1467 const Type* out_t = _igvn->type(out)->make_ptr();
1468 const Type* out_new_t = out_t->meet(TypePtr::NULL_PTR);
1469 bool change = out_new_t != out_t;
1470
1471 for (int j = out->outcnt()-1; change && j >= 0; --j) {
1472 Node* out2 = out->raw_out(j);
1473 if (!out2->is_SafePoint()) {
1474 change = false;
1475 break;
1476 }
1477 }
1478
1479 if (change) {
1480 Node* new_cast = ConstraintCastNode::make_cast_for_type(out->in(0), out->in(1), out_new_t, ConstraintCastNode::DependencyType::NonFloatingNarrowing, nullptr);
1481 _igvn->replace_node(out, new_cast);
1482 _igvn->register_new_node_with_optimizer(new_cast);
1483 }
1484 }
1485
1486 --i;
1487 i = MIN2(i, (int)ophi->outcnt()-1);
1488 }
1489
1490 _igvn->replace_node(ophi, new_phi);
1491 }
1492
1493 void ConnectionGraph::verify_ram_nodes(Compile* C, Node* root) {
1494 if (!C->do_reduce_allocation_merges()) return;
1495
1496 Unique_Node_List ideal_nodes;
1497 ideal_nodes.map(C->live_nodes(), nullptr); // preallocate space
1498 ideal_nodes.push(root);
1499
1500 for (uint next = 0; next < ideal_nodes.size(); ++next) {
1501 Node* n = ideal_nodes.at(next);
1502
1503 if (n->is_SafePointScalarMerge()) {
1504 SafePointScalarMergeNode* merge = n->as_SafePointScalarMerge();
1505
1506 // Validate inputs of merge
1507 for (uint i = 1; i < merge->req(); i++) {
1508 if (merge->in(i) != nullptr && !merge->in(i)->is_top() && !merge->in(i)->is_SafePointScalarObject()) {
1509 assert(false, "SafePointScalarMerge inputs should be null/top or SafePointScalarObject.");
1510 C->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
1511 }
1512 }
1513
1514 // Validate users of merge
1515 for (DUIterator_Fast imax, i = merge->fast_outs(imax); i < imax; i++) {
1516 Node* sfpt = merge->fast_out(i);
1517 if (sfpt->is_SafePoint()) {
1518 int merge_idx = merge->merge_pointer_idx(sfpt->as_SafePoint()->jvms());
1519
1520 if (sfpt->in(merge_idx) != nullptr && sfpt->in(merge_idx)->is_SafePointScalarMerge()) {
1521 assert(false, "SafePointScalarMerge nodes can't be nested.");
1522 C->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
1523 }
1524 } else {
1525 assert(false, "Only safepoints can use SafePointScalarMerge nodes.");
1526 C->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
1527 }
1528 }
1529 }
1530
1531 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1532 Node* m = n->fast_out(i);
1533 ideal_nodes.push(m);
1534 }
1535 }
1536 }
1537
1538 // Returns true if there is an object in the scope of sfn that does not escape globally.
1539 bool ConnectionGraph::has_ea_local_in_scope(SafePointNode* sfn) {
1540 Compile* C = _compile;
1541 for (JVMState* jvms = sfn->jvms(); jvms != nullptr; jvms = jvms->caller()) {
1542 if (C->env()->should_retain_local_variables() || C->env()->jvmti_can_walk_any_space() ||
1543 DeoptimizeObjectsALot) {
1544 // Jvmti agents can access locals. Must provide info about local objects at runtime.
1545 int num_locs = jvms->loc_size();
1546 for (int idx = 0; idx < num_locs; idx++) {
1547 Node* l = sfn->local(jvms, idx);
1548 if (not_global_escape(l)) {
1549 return true;
1550 }
1551 }
1552 }
1553 if (C->env()->jvmti_can_get_owned_monitor_info() ||
1554 C->env()->jvmti_can_walk_any_space() || DeoptimizeObjectsALot) {
1555 // Jvmti agents can read monitors. Must provide info about locked objects at runtime.
1556 int num_mon = jvms->nof_monitors();
1557 for (int idx = 0; idx < num_mon; idx++) {
1558 Node* m = sfn->monitor_obj(jvms, idx);
1559 if (m != nullptr && not_global_escape(m)) {
1560 return true;
1561 }
1562 }
1563 }
1564 }
1565 return false;
1566 }
1567
1568 // Returns true if at least one of the arguments to the call is an object
1569 // that does not escape globally.
1570 bool ConnectionGraph::has_arg_escape(CallJavaNode* call) {
1571 if (call->method() != nullptr) {
1572 uint max_idx = TypeFunc::Parms + call->method()->arg_size();
1573 for (uint idx = TypeFunc::Parms; idx < max_idx; idx++) {
1574 Node* p = call->in(idx);
1575 if (not_global_escape(p)) {
1576 return true;
1577 }
1578 }
1579 } else {
1580 const char* name = call->as_CallStaticJava()->_name;
1581 assert(name != nullptr, "no name");
1582 // no arg escapes through uncommon traps
1583 if (strcmp(name, "uncommon_trap") != 0) {
1584 // process_call_arguments() assumes that all arguments escape globally
1585 const TypeTuple* d = call->tf()->domain_sig();
1586 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1587 const Type* at = d->field_at(i);
1588 if (at->isa_oopptr() != nullptr) {
1589 return true;
1590 }
1591 }
1592 }
1593 }
1594 return false;
1595 }
1596
1597
1598
1599 // Utility function for nodes that load an object
1600 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
1601 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1602 // ThreadLocal has RawPtr type.
1603 const Type* t = _igvn->type(n);
1604 if (t->make_ptr() != nullptr) {
1605 Node* adr = n->in(MemNode::Address);
1606 #ifdef ASSERT
1607 if (!adr->is_AddP()) {
1608 assert(_igvn->type(adr)->isa_rawptr(), "sanity");
1609 } else {
1610 assert((ptnode_adr(adr->_idx) == nullptr ||
1611 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity");
1612 }
1613 #endif
1614 add_local_var_and_edge(n, PointsToNode::NoEscape,
1615 adr, delayed_worklist);
1616 }
1617 }
1618
1619 void ConnectionGraph::add_proj(Node* n, Unique_Node_List* delayed_worklist) {
1620 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() && n->in(0)->as_Call()->returns_pointer()) {
1621 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), delayed_worklist);
1622 } else if (n->in(0)->is_LoadFlat()) {
1623 // Treat LoadFlat outputs similar to a call return value
1624 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), delayed_worklist);
1625 } else if (n->as_Proj()->_con >= TypeFunc::Parms && n->in(0)->is_Call() && n->bottom_type()->isa_ptr()) {
1626 CallNode* call = n->in(0)->as_Call();
1627 assert(call->tf()->returns_inline_type_as_fields(), "");
1628 if (n->as_Proj()->_con == TypeFunc::Parms || !returns_an_argument(call)) {
1629 // either:
1630 // - not an argument returned
1631 // - the returned buffer for a returned scalarized argument
1632 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), delayed_worklist);
1633 } else {
1634 add_local_var(n, PointsToNode::NoEscape);
1635 }
1636 }
1637 }
1638
1639 // Populate Connection Graph with PointsTo nodes and create simple
1640 // connection graph edges.
1641 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
1642 assert(!_verify, "this method should not be called for verification");
1643 PhaseGVN* igvn = _igvn;
1644 uint n_idx = n->_idx;
1645 PointsToNode* n_ptn = ptnode_adr(n_idx);
1646 if (n_ptn != nullptr) {
1647 return; // No need to redefine PointsTo node during first iteration.
1648 }
1649 int opcode = n->Opcode();
1650 bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_to_con_graph(this, igvn, delayed_worklist, n, opcode);
1651 if (gc_handled) {
1652 return; // Ignore node if already handled by GC.
1653 }
1654
1655 if (n->is_Call()) {
1656 // Arguments to allocation and locking don't escape.
1657 if (n->is_AbstractLock()) {
1658 // Put Lock and Unlock nodes on IGVN worklist to process them during
1659 // first IGVN optimization when escape information is still available.
1660 record_for_optimizer(n);
1661 } else if (n->is_Allocate()) {
1662 add_call_node(n->as_Call());
1663 record_for_optimizer(n);
1664 } else {
1665 if (n->is_CallStaticJava()) {
1666 const char* name = n->as_CallStaticJava()->_name;
1667 if (name != nullptr && strcmp(name, "uncommon_trap") == 0) {
1668 return; // Skip uncommon traps
1669 }
1670 }
1671 // Don't mark as processed since call's arguments have to be processed.
1672 delayed_worklist->push(n);
1673 // Check if a call returns an object.
1674 if ((n->as_Call()->returns_pointer() &&
1675 n->as_Call()->proj_out_or_null(TypeFunc::Parms) != nullptr) ||
1676 (n->is_CallStaticJava() &&
1677 n->as_CallStaticJava()->is_boxing_method())) {
1678 add_call_node(n->as_Call());
1679 } else if (n->as_Call()->tf()->returns_inline_type_as_fields()) {
1680 bool returns_oop = false;
1681 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax && !returns_oop; i++) {
1682 ProjNode* pn = n->fast_out(i)->as_Proj();
1683 if (pn->_con >= TypeFunc::Parms && pn->bottom_type()->isa_ptr()) {
1684 returns_oop = true;
1685 }
1686 }
1687 if (returns_oop) {
1688 add_call_node(n->as_Call());
1689 }
1690 }
1691 }
1692 return;
1693 }
1694 // Put this check here to process call arguments since some call nodes
1695 // point to phantom_obj.
1696 if (n_ptn == phantom_obj || n_ptn == null_obj) {
1697 return; // Skip predefined nodes.
1698 }
1699 switch (opcode) {
1700 case Op_AddP: {
1701 Node* base = get_addp_base(n);
1702 PointsToNode* ptn_base = ptnode_adr(base->_idx);
1703 // Field nodes are created for all field types. They are used in
1704 // adjust_scalar_replaceable_state() and split_unique_types().
1705 // Note, non-oop fields will have only base edges in Connection
1706 // Graph because such fields are not used for oop loads and stores.
1707 int offset = address_offset(n, igvn);
1708 add_field(n, PointsToNode::NoEscape, offset);
1709 if (ptn_base == nullptr) {
1710 delayed_worklist->push(n); // Process it later.
1711 } else {
1712 n_ptn = ptnode_adr(n_idx);
1713 add_base(n_ptn->as_Field(), ptn_base);
1714 }
1715 break;
1716 }
1717 case Op_CastX2P:
1718 case Op_CastI2N: {
1719 map_ideal_node(n, phantom_obj);
1720 break;
1721 }
1722 case Op_InlineType:
1723 case Op_CastPP:
1724 case Op_CheckCastPP:
1725 case Op_EncodeP:
1726 case Op_DecodeN:
1727 case Op_EncodePKlass:
1728 case Op_DecodeNKlass: {
1729 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), delayed_worklist);
1730 break;
1731 }
1732 case Op_CMoveP: {
1733 add_local_var(n, PointsToNode::NoEscape);
1734 // Do not add edges during first iteration because some could be
1735 // not defined yet.
1736 delayed_worklist->push(n);
1737 break;
1738 }
1739 case Op_ConP:
1740 case Op_ConN:
1741 case Op_ConNKlass: {
1742 // assume all oop constants globally escape except for null
1743 PointsToNode::EscapeState es;
1744 const Type* t = igvn->type(n);
1745 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) {
1746 es = PointsToNode::NoEscape;
1747 } else {
1748 es = PointsToNode::GlobalEscape;
1749 }
1750 PointsToNode* ptn_con = add_java_object(n, es);
1751 set_not_scalar_replaceable(ptn_con NOT_PRODUCT(COMMA "Constant pointer"));
1752 break;
1753 }
1754 case Op_CreateEx: {
1755 // assume that all exception objects globally escape
1756 map_ideal_node(n, phantom_obj);
1757 break;
1758 }
1759 case Op_LoadKlass:
1760 case Op_LoadNKlass: {
1761 // Unknown class is loaded
1762 map_ideal_node(n, phantom_obj);
1763 break;
1764 }
1765 case Op_LoadP:
1766 case Op_LoadN: {
1767 add_objload_to_connection_graph(n, delayed_worklist);
1768 break;
1769 }
1770 case Op_Parm: {
1771 map_ideal_node(n, phantom_obj);
1772 break;
1773 }
1774 case Op_PartialSubtypeCheck: {
1775 // Produces Null or notNull and is used in only in CmpP so
1776 // phantom_obj could be used.
1777 map_ideal_node(n, phantom_obj); // Result is unknown
1778 break;
1779 }
1780 case Op_Phi: {
1781 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1782 // ThreadLocal has RawPtr type.
1783 const Type* t = n->as_Phi()->type();
1784 if (t->make_ptr() != nullptr) {
1785 add_local_var(n, PointsToNode::NoEscape);
1786 // Do not add edges during first iteration because some could be
1787 // not defined yet.
1788 delayed_worklist->push(n);
1789 }
1790 break;
1791 }
1792 case Op_LoadFlat:
1793 // Treat LoadFlat similar to an unknown call that receives nothing and produces its results
1794 map_ideal_node(n, phantom_obj);
1795 break;
1796 case Op_StoreFlat:
1797 // Treat StoreFlat similar to a call that escapes the stored flattened fields
1798 delayed_worklist->push(n);
1799 break;
1800 case Op_Proj: {
1801 // we are only interested in the oop result projection from a call
1802 add_proj(n, delayed_worklist);
1803 break;
1804 }
1805 case Op_Rethrow: // Exception object escapes
1806 case Op_Return: {
1807 if (n->req() > TypeFunc::Parms &&
1808 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
1809 // Treat Return value as LocalVar with GlobalEscape escape state.
1810 add_local_var_and_edge(n, PointsToNode::GlobalEscape, n->in(TypeFunc::Parms), delayed_worklist);
1811 }
1812 break;
1813 }
1814 case Op_CompareAndExchangeP:
1815 case Op_CompareAndExchangeN:
1816 case Op_GetAndSetP:
1817 case Op_GetAndSetN: {
1818 add_objload_to_connection_graph(n, delayed_worklist);
1819 // fall-through
1820 }
1821 case Op_StoreP:
1822 case Op_StoreN:
1823 case Op_StoreNKlass:
1824 case Op_WeakCompareAndSwapP:
1825 case Op_WeakCompareAndSwapN:
1826 case Op_CompareAndSwapP:
1827 case Op_CompareAndSwapN: {
1828 add_to_congraph_unsafe_access(n, opcode, delayed_worklist);
1829 break;
1830 }
1831 case Op_AryEq:
1832 case Op_CountPositives:
1833 case Op_StrComp:
1834 case Op_StrEquals:
1835 case Op_StrIndexOf:
1836 case Op_StrIndexOfChar:
1837 case Op_StrInflatedCopy:
1838 case Op_StrCompressedCopy:
1839 case Op_VectorizedHashCode:
1840 case Op_EncodeISOArray: {
1841 add_local_var(n, PointsToNode::ArgEscape);
1842 delayed_worklist->push(n); // Process it later.
1843 break;
1844 }
1845 case Op_ThreadLocal: {
1846 PointsToNode* ptn_thr = add_java_object(n, PointsToNode::ArgEscape);
1847 set_not_scalar_replaceable(ptn_thr NOT_PRODUCT(COMMA "Constant pointer"));
1848 break;
1849 }
1850 case Op_Blackhole: {
1851 // All blackhole pointer arguments are globally escaping.
1852 // Only do this if there is at least one pointer argument.
1853 // Do not add edges during first iteration because some could be
1854 // not defined yet, defer to final step.
1855 for (uint i = 0; i < n->req(); i++) {
1856 Node* in = n->in(i);
1857 if (in != nullptr) {
1858 const Type* at = _igvn->type(in);
1859 if (!at->isa_ptr()) continue;
1860
1861 add_local_var(n, PointsToNode::GlobalEscape);
1862 delayed_worklist->push(n);
1863 break;
1864 }
1865 }
1866 break;
1867 }
1868 default:
1869 ; // Do nothing for nodes not related to EA.
1870 }
1871 return;
1872 }
1873
1874 // Add final simple edges to graph.
1875 void ConnectionGraph::add_final_edges(Node *n) {
1876 PointsToNode* n_ptn = ptnode_adr(n->_idx);
1877 #ifdef ASSERT
1878 if (_verify && n_ptn->is_JavaObject())
1879 return; // This method does not change graph for JavaObject.
1880 #endif
1881
1882 if (n->is_Call()) {
1883 process_call_arguments(n->as_Call());
1884 return;
1885 }
1886 assert(n->is_Store() || n->is_LoadStore() || n->is_StoreFlat() ||
1887 ((n_ptn != nullptr) && (n_ptn->ideal_node() != nullptr)),
1888 "node should be registered already");
1889 int opcode = n->Opcode();
1890 bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_final_edges(this, _igvn, n, opcode);
1891 if (gc_handled) {
1892 return; // Ignore node if already handled by GC.
1893 }
1894 switch (opcode) {
1895 case Op_AddP: {
1896 Node* base = get_addp_base(n);
1897 PointsToNode* ptn_base = ptnode_adr(base->_idx);
1898 assert(ptn_base != nullptr, "field's base should be registered");
1899 add_base(n_ptn->as_Field(), ptn_base);
1900 break;
1901 }
1902 case Op_InlineType:
1903 case Op_CastPP:
1904 case Op_CheckCastPP:
1905 case Op_EncodeP:
1906 case Op_DecodeN:
1907 case Op_EncodePKlass:
1908 case Op_DecodeNKlass: {
1909 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), nullptr);
1910 break;
1911 }
1912 case Op_CMoveP: {
1913 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) {
1914 Node* in = n->in(i);
1915 if (in == nullptr) {
1916 continue; // ignore null
1917 }
1918 Node* uncast_in = in->uncast();
1919 if (uncast_in->is_top() || uncast_in == n) {
1920 continue; // ignore top or inputs which go back this node
1921 }
1922 PointsToNode* ptn = ptnode_adr(in->_idx);
1923 assert(ptn != nullptr, "node should be registered");
1924 add_edge(n_ptn, ptn);
1925 }
1926 break;
1927 }
1928 case Op_LoadP:
1929 case Op_LoadN: {
1930 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1931 // ThreadLocal has RawPtr type.
1932 assert(_igvn->type(n)->make_ptr() != nullptr, "Unexpected node type");
1933 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(MemNode::Address), nullptr);
1934 break;
1935 }
1936 case Op_Phi: {
1937 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1938 // ThreadLocal has RawPtr type.
1939 assert(n->as_Phi()->type()->make_ptr() != nullptr, "Unexpected node type");
1940 for (uint i = 1; i < n->req(); i++) {
1941 Node* in = n->in(i);
1942 if (in == nullptr) {
1943 continue; // ignore null
1944 }
1945 Node* uncast_in = in->uncast();
1946 if (uncast_in->is_top() || uncast_in == n) {
1947 continue; // ignore top or inputs which go back this node
1948 }
1949 PointsToNode* ptn = ptnode_adr(in->_idx);
1950 assert(ptn != nullptr, "node should be registered");
1951 add_edge(n_ptn, ptn);
1952 }
1953 break;
1954 }
1955 case Op_StoreFlat: {
1956 // StoreFlat globally escapes its stored flattened fields
1957 InlineTypeNode* value = n->as_StoreFlat()->value();
1958 ciInlineKlass* vk = _igvn->type(value)->inline_klass();
1959 for (int i = 0; i < vk->nof_nonstatic_fields(); i++) {
1960 ciField* field = vk->nonstatic_field_at(i);
1961 if (field->type()->is_primitive_type()) {
1962 continue;
1963 }
1964
1965 Node* field_value = value->field_value_by_offset(field->offset_in_bytes(), true);
1966 PointsToNode* field_value_ptn = ptnode_adr(field_value->_idx);
1967 set_escape_state(field_value_ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA "store into a flat field"));
1968 }
1969 break;
1970 }
1971 case Op_Proj: {
1972 add_proj(n, nullptr);
1973 break;
1974 }
1975 case Op_Rethrow: // Exception object escapes
1976 case Op_Return: {
1977 assert(n->req() > TypeFunc::Parms && _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr(),
1978 "Unexpected node type");
1979 // Treat Return value as LocalVar with GlobalEscape escape state.
1980 add_local_var_and_edge(n, PointsToNode::GlobalEscape, n->in(TypeFunc::Parms), nullptr);
1981 break;
1982 }
1983 case Op_CompareAndExchangeP:
1984 case Op_CompareAndExchangeN:
1985 case Op_GetAndSetP:
1986 case Op_GetAndSetN:{
1987 assert(_igvn->type(n)->make_ptr() != nullptr, "Unexpected node type");
1988 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(MemNode::Address), nullptr);
1989 // fall-through
1990 }
1991 case Op_CompareAndSwapP:
1992 case Op_CompareAndSwapN:
1993 case Op_WeakCompareAndSwapP:
1994 case Op_WeakCompareAndSwapN:
1995 case Op_StoreP:
1996 case Op_StoreN:
1997 case Op_StoreNKlass:{
1998 add_final_edges_unsafe_access(n, opcode);
1999 break;
2000 }
2001 case Op_VectorizedHashCode:
2002 case Op_AryEq:
2003 case Op_CountPositives:
2004 case Op_StrComp:
2005 case Op_StrEquals:
2006 case Op_StrIndexOf:
2007 case Op_StrIndexOfChar:
2008 case Op_StrInflatedCopy:
2009 case Op_StrCompressedCopy:
2010 case Op_EncodeISOArray: {
2011 // char[]/byte[] arrays passed to string intrinsic do not escape but
2012 // they are not scalar replaceable. Adjust escape state for them.
2013 // Start from in(2) edge since in(1) is memory edge.
2014 for (uint i = 2; i < n->req(); i++) {
2015 Node* adr = n->in(i);
2016 const Type* at = _igvn->type(adr);
2017 if (!adr->is_top() && at->isa_ptr()) {
2018 assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
2019 at->isa_ptr() != nullptr, "expecting a pointer");
2020 if (adr->is_AddP()) {
2021 adr = get_addp_base(adr);
2022 }
2023 PointsToNode* ptn = ptnode_adr(adr->_idx);
2024 assert(ptn != nullptr, "node should be registered");
2025 add_edge(n_ptn, ptn);
2026 }
2027 }
2028 break;
2029 }
2030 case Op_Blackhole: {
2031 // All blackhole pointer arguments are globally escaping.
2032 for (uint i = 0; i < n->req(); i++) {
2033 Node* in = n->in(i);
2034 if (in != nullptr) {
2035 const Type* at = _igvn->type(in);
2036 if (!at->isa_ptr()) continue;
2037
2038 if (in->is_AddP()) {
2039 in = get_addp_base(in);
2040 }
2041
2042 PointsToNode* ptn = ptnode_adr(in->_idx);
2043 assert(ptn != nullptr, "should be defined already");
2044 set_escape_state(ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA "blackhole"));
2045 add_edge(n_ptn, ptn);
2046 }
2047 }
2048 break;
2049 }
2050 default: {
2051 // This method should be called only for EA specific nodes which may
2052 // miss some edges when they were created.
2053 #ifdef ASSERT
2054 n->dump(1);
2055 #endif
2056 guarantee(false, "unknown node");
2057 }
2058 }
2059 return;
2060 }
2061
2062 void ConnectionGraph::add_to_congraph_unsafe_access(Node* n, uint opcode, Unique_Node_List* delayed_worklist) {
2063 Node* adr = n->in(MemNode::Address);
2064 const Type* adr_type = _igvn->type(adr);
2065 adr_type = adr_type->make_ptr();
2066 if (adr_type == nullptr) {
2067 return; // skip dead nodes
2068 }
2069 if (adr_type->isa_oopptr()
2070 || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
2071 && adr_type == TypeRawPtr::NOTNULL
2072 && is_captured_store_address(adr))) {
2073 delayed_worklist->push(n); // Process it later.
2074 #ifdef ASSERT
2075 assert (adr->is_AddP(), "expecting an AddP");
2076 if (adr_type == TypeRawPtr::NOTNULL) {
2077 // Verify a raw address for a store captured by Initialize node.
2078 int offs = (int) _igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
2079 assert(offs != Type::OffsetBot, "offset must be a constant");
2080 }
2081 #endif
2082 } else {
2083 // Ignore copy the displaced header to the BoxNode (OSR compilation).
2084 if (adr->is_BoxLock()) {
2085 return;
2086 }
2087 // Stored value escapes in unsafe access.
2088 if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
2089 delayed_worklist->push(n); // Process unsafe access later.
2090 return;
2091 }
2092 #ifdef ASSERT
2093 n->dump(1);
2094 assert(false, "not unsafe");
2095 #endif
2096 }
2097 }
2098
2099 bool ConnectionGraph::add_final_edges_unsafe_access(Node* n, uint opcode) {
2100 Node* adr = n->in(MemNode::Address);
2101 const Type *adr_type = _igvn->type(adr);
2102 adr_type = adr_type->make_ptr();
2103 #ifdef ASSERT
2104 if (adr_type == nullptr) {
2105 n->dump(1);
2106 assert(adr_type != nullptr, "dead node should not be on list");
2107 return true;
2108 }
2109 #endif
2110
2111 if (adr_type->isa_oopptr()
2112 || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
2113 && adr_type == TypeRawPtr::NOTNULL
2114 && is_captured_store_address(adr))) {
2115 // Point Address to Value
2116 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
2117 assert(adr_ptn != nullptr &&
2118 adr_ptn->as_Field()->is_oop(), "node should be registered");
2119 Node* val = n->in(MemNode::ValueIn);
2120 PointsToNode* ptn = ptnode_adr(val->_idx);
2121 assert(ptn != nullptr, "node should be registered");
2122 add_edge(adr_ptn, ptn);
2123 return true;
2124 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
2125 // Stored value escapes in unsafe access.
2126 Node* val = n->in(MemNode::ValueIn);
2127 PointsToNode* ptn = ptnode_adr(val->_idx);
2128 assert(ptn != nullptr, "node should be registered");
2129 set_escape_state(ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA "stored at raw address"));
2130 // Add edge to object for unsafe access with offset.
2131 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
2132 assert(adr_ptn != nullptr, "node should be registered");
2133 if (adr_ptn->is_Field()) {
2134 assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
2135 add_edge(adr_ptn, ptn);
2136 }
2137 return true;
2138 }
2139 #ifdef ASSERT
2140 n->dump(1);
2141 assert(false, "not unsafe");
2142 #endif
2143 return false;
2144 }
2145
2146 // Iterate over the domains for the scalarized and non scalarized calling conventions: Only move to the next element
2147 // in the non scalarized calling convention once all elements of the scalarized calling convention for that parameter
2148 // have been iterated over. So (ignoring hidden arguments such as the null marker) iterating over:
2149 // value class MyValue {
2150 // int f1;
2151 // float f2;
2152 // }
2153 // void m(Object o, MyValue v, int i)
2154 // produces the pairs:
2155 // (Object, Object), (Myvalue, int), (MyValue, float), (int, int)
2156 class DomainIterator : public StackObj {
2157 private:
2158 const TypeTuple* _domain;
2159 const TypeTuple* _domain_cc;
2160 const GrowableArray<SigEntry>* _sig_cc;
2161
2162 uint _i_domain;
2163 uint _i_domain_cc;
2164 int _i_sig_cc;
2165 uint _depth;
2166 uint _first_field_pos;
2167 const bool _is_static;
2168
2169 void next_helper() {
2170 if (_sig_cc == nullptr) {
2171 return;
2172 }
2173 BasicType prev_bt = _i_sig_cc > 0 ? _sig_cc->at(_i_sig_cc-1)._bt : T_ILLEGAL;
2174 BasicType prev_prev_bt = _i_sig_cc > 1 ? _sig_cc->at(_i_sig_cc-2)._bt : T_ILLEGAL;
2175 while (_i_sig_cc < _sig_cc->length()) {
2176 BasicType bt = _sig_cc->at(_i_sig_cc)._bt;
2177 assert(bt != T_VOID || _sig_cc->at(_i_sig_cc-1)._bt == prev_bt, "incorrect prev bt");
2178 if (bt == T_METADATA) {
2179 if (_depth == 0) {
2180 _first_field_pos = _i_domain_cc;
2181 }
2182 _depth++;
2183 } else if (bt == T_VOID && (prev_bt != T_LONG && prev_bt != T_DOUBLE)) {
2184 _depth--;
2185 if (_depth == 0) {
2186 _i_domain++;
2187 }
2188 } else if (bt == T_OBJECT && prev_bt == T_METADATA && (_is_static || _i_domain > 0) && _sig_cc->at(_i_sig_cc)._offset == 0) {
2189 assert(_sig_cc->at(_i_sig_cc)._vt_oop, "buffer expected right after T_METADATA");
2190 assert(_depth == 1, "only root value has buffer");
2191 _i_domain_cc++;
2192 _first_field_pos = _i_domain_cc;
2193 } else if (bt == T_BOOLEAN && prev_prev_bt == T_METADATA && (_is_static || _i_domain > 0) && _sig_cc->at(_i_sig_cc)._offset == -1) {
2194 assert(_sig_cc->at(_i_sig_cc)._null_marker, "null marker expected right after T_METADATA");
2195 assert(_depth == 1, "only root value null marker");
2196 _i_domain_cc++;
2197 _first_field_pos = _i_domain_cc;
2198 } else {
2199 return;
2200 }
2201 prev_prev_bt = prev_bt;
2202 prev_bt = bt;
2203 _i_sig_cc++;
2204 }
2205 }
2206
2207 public:
2208
2209 DomainIterator(CallJavaNode* call) :
2210 _domain(call->tf()->domain_sig()),
2211 _domain_cc(call->tf()->domain_cc()),
2212 _sig_cc(call->method()->get_sig_cc()),
2213 _i_domain(TypeFunc::Parms),
2214 _i_domain_cc(TypeFunc::Parms),
2215 _i_sig_cc(0),
2216 _depth(0),
2217 _first_field_pos(0),
2218 _is_static(call->method()->is_static()) {
2219 next_helper();
2220 }
2221
2222 bool has_next() const {
2223 assert(_sig_cc == nullptr || (_i_sig_cc < _sig_cc->length()) == (_i_domain < _domain->cnt()), "should reach end in sync");
2224 assert((_i_domain < _domain->cnt()) == (_i_domain_cc < _domain_cc->cnt()), "should reach end in sync");
2225 return _i_domain < _domain->cnt();
2226 }
2227
2228 void next() {
2229 assert(_depth != 0 || _domain->field_at(_i_domain) == _domain_cc->field_at(_i_domain_cc), "should produce same non scalarized elements");
2230 _i_sig_cc++;
2231 if (_depth == 0) {
2232 _i_domain++;
2233 }
2234 _i_domain_cc++;
2235 next_helper();
2236 }
2237
2238 uint i_domain() const {
2239 return _i_domain;
2240 }
2241
2242 uint i_domain_cc() const {
2243 return _i_domain_cc;
2244 }
2245
2246 const Type* current_domain() const {
2247 return _domain->field_at(_i_domain);
2248 }
2249
2250 const Type* current_domain_cc() const {
2251 return _domain_cc->field_at(_i_domain_cc);
2252 }
2253
2254 uint first_field_pos() const {
2255 assert(_first_field_pos >= TypeFunc::Parms, "not yet updated?");
2256 return _first_field_pos;
2257 }
2258 };
2259
2260 // Determine whether any arguments are returned.
2261 bool ConnectionGraph::returns_an_argument(CallNode* call) {
2262 ciMethod* meth = call->as_CallJava()->method();
2263 BCEscapeAnalyzer* call_analyzer = meth->get_bcea();
2264 if (call_analyzer == nullptr) {
2265 return false;
2266 }
2267
2268 const TypeTuple* d = call->tf()->domain_sig();
2269 bool ret_arg = false;
2270 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
2271 if (d->field_at(i)->isa_ptr() != nullptr &&
2272 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
2273 if (meth->is_scalarized_arg(i - TypeFunc::Parms) && !compatible_return(call->as_CallJava(), i)) {
2274 return false;
2275 }
2276 if (call->tf()->returns_inline_type_as_fields() != meth->is_scalarized_arg(i - TypeFunc::Parms)) {
2277 return false;
2278 }
2279 ret_arg = true;
2280 }
2281 }
2282 return ret_arg;
2283 }
2284
2285 void ConnectionGraph::add_call_node(CallNode* call) {
2286 assert(call->returns_pointer() || call->tf()->returns_inline_type_as_fields(), "only for call which returns pointer");
2287 uint call_idx = call->_idx;
2288 if (call->is_Allocate()) {
2289 Node* k = call->in(AllocateNode::KlassNode);
2290 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr();
2291 assert(kt != nullptr, "TypeKlassPtr required.");
2292 PointsToNode::EscapeState es = PointsToNode::NoEscape;
2293 bool scalar_replaceable = true;
2294 NOT_PRODUCT(const char* nsr_reason = "");
2295 if (call->is_AllocateArray()) {
2296 if (!kt->isa_aryklassptr()) { // StressReflectiveCode
2297 es = PointsToNode::GlobalEscape;
2298 } else {
2299 int length = call->in(AllocateNode::ALength)->find_int_con(-1);
2300 if (length < 0) {
2301 // Not scalar replaceable if the length is not constant.
2302 scalar_replaceable = false;
2303 NOT_PRODUCT(nsr_reason = "has a non-constant length");
2304 } else if (length > EliminateAllocationArraySizeLimit) {
2305 // Not scalar replaceable if the length is too big.
2306 scalar_replaceable = false;
2307 NOT_PRODUCT(nsr_reason = "has a length that is too big");
2308 }
2309 }
2310 } else { // Allocate instance
2311 if (!kt->isa_instklassptr()) { // StressReflectiveCode
2312 es = PointsToNode::GlobalEscape;
2313 } else {
2314 const TypeInstKlassPtr* ikt = kt->is_instklassptr();
2315 ciInstanceKlass* ik = ikt->klass_is_exact() ? ikt->exact_klass()->as_instance_klass() : ikt->instance_klass();
2316 if (ik->is_subclass_of(_compile->env()->Thread_klass()) ||
2317 ik->is_subclass_of(_compile->env()->Reference_klass()) ||
2318 !ik->can_be_instantiated() ||
2319 ik->has_finalizer()) {
2320 es = PointsToNode::GlobalEscape;
2321 } else {
2322 int nfields = ik->as_instance_klass()->nof_nonstatic_fields();
2323 if (nfields > EliminateAllocationFieldsLimit) {
2324 // Not scalar replaceable if there are too many fields.
2325 scalar_replaceable = false;
2326 NOT_PRODUCT(nsr_reason = "has too many fields");
2327 }
2328 }
2329 }
2330 }
2331 add_java_object(call, es);
2332 PointsToNode* ptn = ptnode_adr(call_idx);
2333 if (!scalar_replaceable && ptn->scalar_replaceable()) {
2334 set_not_scalar_replaceable(ptn NOT_PRODUCT(COMMA nsr_reason));
2335 }
2336 } else if (call->is_CallStaticJava()) {
2337 // Call nodes could be different types:
2338 //
2339 // 1. CallDynamicJavaNode (what happened during call is unknown):
2340 //
2341 // - mapped to GlobalEscape JavaObject node if oop is returned;
2342 //
2343 // - all oop arguments are escaping globally;
2344 //
2345 // 2. CallStaticJavaNode (execute bytecode analysis if possible):
2346 //
2347 // - the same as CallDynamicJavaNode if can't do bytecode analysis;
2348 //
2349 // - mapped to GlobalEscape JavaObject node if unknown oop is returned;
2350 // - mapped to NoEscape JavaObject node if non-escaping object allocated
2351 // during call is returned;
2352 // - mapped to ArgEscape LocalVar node pointed to object arguments
2353 // which are returned and does not escape during call;
2354 //
2355 // - oop arguments escaping status is defined by bytecode analysis;
2356 //
2357 // For a static call, we know exactly what method is being called.
2358 // Use bytecode estimator to record whether the call's return value escapes.
2359 ciMethod* meth = call->as_CallJava()->method();
2360 if (meth == nullptr) {
2361 const char* name = call->as_CallStaticJava()->_name;
2362 assert(call->as_CallStaticJava()->is_call_to_multianewarray_stub() ||
2363 strncmp(name, "load_unknown_inline", 19) == 0 ||
2364 strncmp(name, "store_inline_type_fields_to_buf", 31) == 0, "TODO: add failed case check");
2365 // Returns a newly allocated non-escaped object.
2366 add_java_object(call, PointsToNode::NoEscape);
2367 set_not_scalar_replaceable(ptnode_adr(call_idx) NOT_PRODUCT(COMMA "is result of multinewarray"));
2368 } else if (meth->is_boxing_method()) {
2369 // Returns boxing object
2370 PointsToNode::EscapeState es;
2371 vmIntrinsics::ID intr = meth->intrinsic_id();
2372 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) {
2373 // It does not escape if object is always allocated.
2374 es = PointsToNode::NoEscape;
2375 } else {
2376 // It escapes globally if object could be loaded from cache.
2377 es = PointsToNode::GlobalEscape;
2378 }
2379 add_java_object(call, es);
2380 if (es == PointsToNode::GlobalEscape) {
2381 set_not_scalar_replaceable(ptnode_adr(call->_idx) NOT_PRODUCT(COMMA "object can be loaded from boxing cache"));
2382 }
2383 } else {
2384 BCEscapeAnalyzer* call_analyzer = meth->get_bcea();
2385 call_analyzer->copy_dependencies(_compile->dependencies());
2386 if (call_analyzer->is_return_allocated()) {
2387 // Returns a newly allocated non-escaped object, simply
2388 // update dependency information.
2389 // Mark it as NoEscape so that objects referenced by
2390 // it's fields will be marked as NoEscape at least.
2391 add_java_object(call, PointsToNode::NoEscape);
2392 set_not_scalar_replaceable(ptnode_adr(call_idx) NOT_PRODUCT(COMMA "is result of call"));
2393 } else {
2394 // For non scalarized argument/return: add_proj() adds an edge between the return projection and the call,
2395 // process_call_arguments() adds an edge between the call and the argument
2396 // For scalarized argument/return: process_call_arguments() adds an edge between a call projection for a field
2397 // and the argument input to the call for that field. An edge is added between the projection for the returned
2398 // buffer and the call.
2399 if (returns_an_argument(call) && !call->tf()->returns_inline_type_as_fields()) {
2400 // returns non scalarized argument
2401 add_local_var(call, PointsToNode::ArgEscape);
2402 } else {
2403 // Returns unknown object or scalarized argument being returned
2404 map_ideal_node(call, phantom_obj);
2405 }
2406 }
2407 }
2408 } else {
2409 // An other type of call, assume the worst case:
2410 // returned value is unknown and globally escapes.
2411 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check");
2412 map_ideal_node(call, phantom_obj);
2413 }
2414 }
2415
2416 // Check that the return type is compatible with the type of the argument being returned i.e. that there's no cast that
2417 // fails in the method
2418 bool ConnectionGraph::compatible_return(CallJavaNode* call, uint k) {
2419 return call->tf()->domain_sig()->field_at(k)->is_instptr()->instance_klass() == call->tf()->range_sig()->field_at(TypeFunc::Parms)->is_instptr()->instance_klass();
2420 }
2421
2422 void ConnectionGraph::process_call_arguments(CallNode *call) {
2423 bool is_arraycopy = false;
2424 switch (call->Opcode()) {
2425 #ifdef ASSERT
2426 case Op_Allocate:
2427 case Op_AllocateArray:
2428 case Op_Lock:
2429 case Op_Unlock:
2430 assert(false, "should be done already");
2431 break;
2432 #endif
2433 case Op_ArrayCopy:
2434 case Op_CallLeafNoFP:
2435 // Most array copies are ArrayCopy nodes at this point but there
2436 // are still a few direct calls to the copy subroutines (See
2437 // PhaseStringOpts::copy_string())
2438 is_arraycopy = (call->Opcode() == Op_ArrayCopy) ||
2439 call->as_CallLeaf()->is_call_to_arraycopystub();
2440 // fall through
2441 case Op_CallLeafVector:
2442 case Op_CallLeaf: {
2443 // Stub calls, objects do not escape but they are not scale replaceable.
2444 // Adjust escape state for outgoing arguments.
2445 const TypeTuple * d = call->tf()->domain_sig();
2446 bool src_has_oops = false;
2447 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
2448 const Type* at = d->field_at(i);
2449 Node *arg = call->in(i);
2450 if (arg == nullptr) {
2451 continue;
2452 }
2453 const Type *aat = _igvn->type(arg);
2454 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr()) {
2455 continue;
2456 }
2457 if (arg->is_AddP()) {
2458 //
2459 // The inline_native_clone() case when the arraycopy stub is called
2460 // after the allocation before Initialize and CheckCastPP nodes.
2461 // Or normal arraycopy for object arrays case.
2462 //
2463 // Set AddP's base (Allocate) as not scalar replaceable since
2464 // pointer to the base (with offset) is passed as argument.
2465 //
2466 arg = get_addp_base(arg);
2467 }
2468 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
2469 assert(arg_ptn != nullptr, "should be registered");
2470 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state();
2471 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) {
2472 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
2473 aat->isa_ptr() != nullptr, "expecting an Ptr");
2474 bool arg_has_oops = aat->isa_oopptr() &&
2475 (aat->isa_instptr() ||
2476 (aat->isa_aryptr() && (aat->isa_aryptr()->elem() == Type::BOTTOM || aat->isa_aryptr()->elem()->make_oopptr() != nullptr)) ||
2477 (aat->isa_aryptr() && aat->isa_aryptr()->elem() != nullptr &&
2478 aat->isa_aryptr()->is_flat() &&
2479 aat->isa_aryptr()->elem()->inline_klass()->contains_oops()));
2480 if (i == TypeFunc::Parms) {
2481 src_has_oops = arg_has_oops;
2482 }
2483 //
2484 // src or dst could be j.l.Object when other is basic type array:
2485 //
2486 // arraycopy(char[],0,Object*,0,size);
2487 // arraycopy(Object*,0,char[],0,size);
2488 //
2489 // Don't add edges in such cases.
2490 //
2491 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy &&
2492 arg_has_oops && (i > TypeFunc::Parms);
2493 #ifdef ASSERT
2494 if (!(is_arraycopy ||
2495 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(call) ||
2496 (call->as_CallLeaf()->_name != nullptr &&
2497 (strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 ||
2498 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 ||
2499 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 ||
2500 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 ||
2501 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 ||
2502 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 ||
2503 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 ||
2504 strcmp(call->as_CallLeaf()->_name, "electronicCodeBook_encryptAESCrypt") == 0 ||
2505 strcmp(call->as_CallLeaf()->_name, "electronicCodeBook_decryptAESCrypt") == 0 ||
2506 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 ||
2507 strcmp(call->as_CallLeaf()->_name, "galoisCounterMode_AESCrypt") == 0 ||
2508 strcmp(call->as_CallLeaf()->_name, "poly1305_processBlocks") == 0 ||
2509 strcmp(call->as_CallLeaf()->_name, "intpoly_montgomeryMult_P256") == 0 ||
2510 strcmp(call->as_CallLeaf()->_name, "intpoly_assign") == 0 ||
2511 strcmp(call->as_CallLeaf()->_name, "intpoly_mult_25519") == 0 ||
2512 strcmp(call->as_CallLeaf()->_name, "intpoly_square_25519") == 0 ||
2513 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 ||
2514 strcmp(call->as_CallLeaf()->_name, "chacha20Block") == 0 ||
2515 strcmp(call->as_CallLeaf()->_name, "kyberNtt") == 0 ||
2516 strcmp(call->as_CallLeaf()->_name, "kyberInverseNtt") == 0 ||
2517 strcmp(call->as_CallLeaf()->_name, "kyberNttMult") == 0 ||
2518 strcmp(call->as_CallLeaf()->_name, "kyberAddPoly_2") == 0 ||
2519 strcmp(call->as_CallLeaf()->_name, "kyberAddPoly_3") == 0 ||
2520 strcmp(call->as_CallLeaf()->_name, "kyber12To16") == 0 ||
2521 strcmp(call->as_CallLeaf()->_name, "kyberBarrettReduce") == 0 ||
2522 strcmp(call->as_CallLeaf()->_name, "dilithiumAlmostNtt") == 0 ||
2523 strcmp(call->as_CallLeaf()->_name, "dilithiumAlmostInverseNtt") == 0 ||
2524 strcmp(call->as_CallLeaf()->_name, "dilithiumNttMult") == 0 ||
2525 strcmp(call->as_CallLeaf()->_name, "dilithiumMontMulByConstant") == 0 ||
2526 strcmp(call->as_CallLeaf()->_name, "dilithiumDecomposePoly") == 0 ||
2527 strcmp(call->as_CallLeaf()->_name, "encodeBlock") == 0 ||
2528 strcmp(call->as_CallLeaf()->_name, "decodeBlock") == 0 ||
2529 strcmp(call->as_CallLeaf()->_name, "md5_implCompress") == 0 ||
2530 strcmp(call->as_CallLeaf()->_name, "md5_implCompressMB") == 0 ||
2531 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 ||
2532 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 ||
2533 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 ||
2534 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 ||
2535 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 ||
2536 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 ||
2537 strcmp(call->as_CallLeaf()->_name, "sha3_implCompress") == 0 ||
2538 strcmp(call->as_CallLeaf()->_name, "double_keccak") == 0 ||
2539 strcmp(call->as_CallLeaf()->_name, "quad_keccak") == 0 ||
2540 strcmp(call->as_CallLeaf()->_name, "sha3_implCompressMB") == 0 ||
2541 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 ||
2542 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 ||
2543 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 ||
2544 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 ||
2545 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 ||
2546 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0 ||
2547 strcmp(call->as_CallLeaf()->_name, "load_unknown_inline") == 0 ||
2548 strcmp(call->as_CallLeaf()->_name, "store_unknown_inline") == 0 ||
2549 strcmp(call->as_CallLeaf()->_name, "store_inline_type_fields_to_buf") == 0 ||
2550 strcmp(call->as_CallLeaf()->_name, "bigIntegerRightShiftWorker") == 0 ||
2551 strcmp(call->as_CallLeaf()->_name, "bigIntegerLeftShiftWorker") == 0 ||
2552 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0 ||
2553 strcmp(call->as_CallLeaf()->_name, "stringIndexOf") == 0 ||
2554 strcmp(call->as_CallLeaf()->_name, "arraysort_stub") == 0 ||
2555 strcmp(call->as_CallLeaf()->_name, "array_partition_stub") == 0 ||
2556 strcmp(call->as_CallLeaf()->_name, "get_class_id_intrinsic") == 0 ||
2557 strcmp(call->as_CallLeaf()->_name, "unsafe_setmemory") == 0)
2558 ))) {
2559 call->dump();
2560 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name);
2561 }
2562 #endif
2563 // Always process arraycopy's destination object since
2564 // we need to add all possible edges to references in
2565 // source object.
2566 if (arg_esc >= PointsToNode::ArgEscape &&
2567 !arg_is_arraycopy_dest) {
2568 continue;
2569 }
2570 PointsToNode::EscapeState es = PointsToNode::ArgEscape;
2571 if (call->is_ArrayCopy()) {
2572 ArrayCopyNode* ac = call->as_ArrayCopy();
2573 if (ac->is_clonebasic() ||
2574 ac->is_arraycopy_validated() ||
2575 ac->is_copyof_validated() ||
2576 ac->is_copyofrange_validated()) {
2577 es = PointsToNode::NoEscape;
2578 }
2579 }
2580 set_escape_state(arg_ptn, es NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
2581 if (arg_is_arraycopy_dest) {
2582 Node* src = call->in(TypeFunc::Parms);
2583 if (src->is_AddP()) {
2584 src = get_addp_base(src);
2585 }
2586 PointsToNode* src_ptn = ptnode_adr(src->_idx);
2587 assert(src_ptn != nullptr, "should be registered");
2588 // Special arraycopy edge:
2589 // Only escape state of destination object's fields affects
2590 // escape state of fields in source object.
2591 add_arraycopy(call, es, src_ptn, arg_ptn);
2592 }
2593 }
2594 }
2595 break;
2596 }
2597 case Op_CallStaticJava: {
2598 // For a static call, we know exactly what method is being called.
2599 // Use bytecode estimator to record the call's escape affects
2600 #ifdef ASSERT
2601 const char* name = call->as_CallStaticJava()->_name;
2602 assert((name == nullptr || strcmp(name, "uncommon_trap") != 0), "normal calls only");
2603 #endif
2604 ciMethod* meth = call->as_CallJava()->method();
2605 if ((meth != nullptr) && meth->is_boxing_method()) {
2606 break; // Boxing methods do not modify any oops.
2607 }
2608 BCEscapeAnalyzer* call_analyzer = (meth !=nullptr) ? meth->get_bcea() : nullptr;
2609 // fall-through if not a Java method or no analyzer information
2610 if (call_analyzer != nullptr) {
2611 PointsToNode* call_ptn = ptnode_adr(call->_idx);
2612 bool ret_arg = returns_an_argument(call);
2613 for (DomainIterator di(call->as_CallJava()); di.has_next(); di.next()) {
2614 int k = di.i_domain() - TypeFunc::Parms;
2615 const Type* at = di.current_domain_cc();
2616 Node* arg = call->in(di.i_domain_cc());
2617 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
2618 assert(!call_analyzer->is_arg_returned(k) || !meth->is_scalarized_arg(k) ||
2619 !compatible_return(call->as_CallJava(), di.i_domain()) ||
2620 call->proj_out_or_null(di.i_domain_cc() - di.first_field_pos() + TypeFunc::Parms + 1) == nullptr ||
2621 _igvn->type(call->proj_out_or_null(di.i_domain_cc() - di.first_field_pos() + TypeFunc::Parms + 1)) == at,
2622 "scalarized return and scalarized argument should match");
2623 if (at->isa_ptr() != nullptr && call_analyzer->is_arg_returned(k) && ret_arg) {
2624 // The call returns arguments.
2625 if (meth->is_scalarized_arg(k)) {
2626 ProjNode* res_proj = call->proj_out_or_null(di.i_domain_cc() - di.first_field_pos() + TypeFunc::Parms + 1);
2627 if (res_proj != nullptr) {
2628 assert(_igvn->type(res_proj)->isa_ptr(), "scalarized return and scalarized argument should match");
2629 if (res_proj->_con != TypeFunc::Parms) {
2630 // add an edge between the result projection for a field and the argument projection for the same argument field
2631 PointsToNode* proj_ptn = ptnode_adr(res_proj->_idx);
2632 add_edge(proj_ptn, arg_ptn);
2633 if (!call_analyzer->is_return_local()) {
2634 add_edge(proj_ptn, phantom_obj);
2635 }
2636 }
2637 }
2638 } else if (call_ptn != nullptr) { // Is call's result used?
2639 assert(call_ptn->is_LocalVar(), "node should be registered");
2640 assert(arg_ptn != nullptr, "node should be registered");
2641 add_edge(call_ptn, arg_ptn);
2642 }
2643 }
2644 if (at->isa_oopptr() != nullptr &&
2645 arg_ptn->escape_state() < PointsToNode::GlobalEscape) {
2646 if (!call_analyzer->is_arg_stack(k)) {
2647 // The argument global escapes
2648 set_escape_state(arg_ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
2649 } else {
2650 set_escape_state(arg_ptn, PointsToNode::ArgEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
2651 if (!call_analyzer->is_arg_local(k)) {
2652 // The argument itself doesn't escape, but any fields might
2653 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
2654 }
2655 }
2656 }
2657 }
2658 if (call_ptn != nullptr && call_ptn->is_LocalVar()) {
2659 // The call returns arguments.
2660 assert(call_ptn->edge_count() > 0, "sanity");
2661 if (!call_analyzer->is_return_local()) {
2662 // Returns also unknown object.
2663 add_edge(call_ptn, phantom_obj);
2664 }
2665 }
2666 break;
2667 }
2668 }
2669 default: {
2670 // Fall-through here if not a Java method or no analyzer information
2671 // or some other type of call, assume the worst case: all arguments
2672 // globally escape.
2673 const TypeTuple* d = call->tf()->domain_cc();
2674 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
2675 const Type* at = d->field_at(i);
2676 if (at->isa_oopptr() != nullptr) {
2677 Node* arg = call->in(i);
2678 if (arg->is_AddP()) {
2679 arg = get_addp_base(arg);
2680 }
2681 assert(ptnode_adr(arg->_idx) != nullptr, "should be defined already");
2682 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape NOT_PRODUCT(COMMA trace_arg_escape_message(call)));
2683 }
2684 }
2685 }
2686 }
2687 }
2688
2689
2690 // Finish Graph construction.
2691 bool ConnectionGraph::complete_connection_graph(
2692 GrowableArray<PointsToNode*>& ptnodes_worklist,
2693 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist,
2694 GrowableArray<JavaObjectNode*>& java_objects_worklist,
2695 GrowableArray<FieldNode*>& oop_fields_worklist) {
2696 // Normally only 1-3 passes needed to build Connection Graph depending
2697 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler.
2698 // Set limit to 20 to catch situation when something did go wrong and
2699 // bailout Escape Analysis.
2700 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag.
2701 #define GRAPH_BUILD_ITER_LIMIT 20
2702
2703 // Propagate GlobalEscape and ArgEscape escape states and check that
2704 // we still have non-escaping objects. The method pushs on _worklist
2705 // Field nodes which reference phantom_object.
2706 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist)) {
2707 return false; // Nothing to do.
2708 }
2709 // Now propagate references to all JavaObject nodes.
2710 int java_objects_length = java_objects_worklist.length();
2711 elapsedTimer build_time;
2712 build_time.start();
2713 elapsedTimer time;
2714 bool timeout = false;
2715 int new_edges = 1;
2716 int iterations = 0;
2717 do {
2718 while ((new_edges > 0) &&
2719 (iterations++ < GRAPH_BUILD_ITER_LIMIT)) {
2720 double start_time = time.seconds();
2721 time.start();
2722 new_edges = 0;
2723 // Propagate references to phantom_object for nodes pushed on _worklist
2724 // by find_non_escaped_objects() and find_field_value().
2725 new_edges += add_java_object_edges(phantom_obj, false);
2726 for (int next = 0; next < java_objects_length; ++next) {
2727 JavaObjectNode* ptn = java_objects_worklist.at(next);
2728 new_edges += add_java_object_edges(ptn, true);
2729
2730 #define SAMPLE_SIZE 4
2731 if ((next % SAMPLE_SIZE) == 0) {
2732 // Each 4 iterations calculate how much time it will take
2733 // to complete graph construction.
2734 time.stop();
2735 // Poll for requests from shutdown mechanism to quiesce compiler
2736 // because Connection graph construction may take long time.
2737 CompileBroker::maybe_block();
2738 double stop_time = time.seconds();
2739 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE;
2740 double time_until_end = time_per_iter * (double)(java_objects_length - next);
2741 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) {
2742 timeout = true;
2743 break; // Timeout
2744 }
2745 start_time = stop_time;
2746 time.start();
2747 }
2748 #undef SAMPLE_SIZE
2749
2750 }
2751 if (timeout) break;
2752 if (new_edges > 0) {
2753 // Update escape states on each iteration if graph was updated.
2754 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist)) {
2755 return false; // Nothing to do.
2756 }
2757 }
2758 time.stop();
2759 if (time.seconds() >= EscapeAnalysisTimeout) {
2760 timeout = true;
2761 break;
2762 }
2763 _compile->print_method(PHASE_EA_COMPLETE_CONNECTION_GRAPH_ITER, 5);
2764 }
2765 if ((iterations < GRAPH_BUILD_ITER_LIMIT) && !timeout) {
2766 time.start();
2767 // Find fields which have unknown value.
2768 int fields_length = oop_fields_worklist.length();
2769 for (int next = 0; next < fields_length; next++) {
2770 FieldNode* field = oop_fields_worklist.at(next);
2771 if (field->edge_count() == 0) {
2772 new_edges += find_field_value(field);
2773 // This code may added new edges to phantom_object.
2774 // Need an other cycle to propagate references to phantom_object.
2775 }
2776 }
2777 time.stop();
2778 if (time.seconds() >= EscapeAnalysisTimeout) {
2779 timeout = true;
2780 break;
2781 }
2782 } else {
2783 new_edges = 0; // Bailout
2784 }
2785 } while (new_edges > 0);
2786
2787 build_time.stop();
2788 _build_time = build_time.seconds();
2789 _build_iterations = iterations;
2790
2791 // Bailout if passed limits.
2792 if ((iterations >= GRAPH_BUILD_ITER_LIMIT) || timeout) {
2793 Compile* C = _compile;
2794 if (C->log() != nullptr) {
2795 C->log()->begin_elem("connectionGraph_bailout reason='reached ");
2796 C->log()->text("%s", timeout ? "time" : "iterations");
2797 C->log()->end_elem(" limit'");
2798 }
2799 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build during invocation %d (%f sec, %d iterations) with %d nodes and worklist size %d",
2800 _invocation, _build_time, _build_iterations, nodes_size(), ptnodes_worklist.length());
2801 // Possible infinite build_connection_graph loop,
2802 // bailout (no changes to ideal graph were made).
2803 return false;
2804 }
2805
2806 #undef GRAPH_BUILD_ITER_LIMIT
2807
2808 // Find fields initialized by null for non-escaping Allocations.
2809 int non_escaped_length = non_escaped_allocs_worklist.length();
2810 for (int next = 0; next < non_escaped_length; next++) {
2811 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
2812 PointsToNode::EscapeState es = ptn->escape_state();
2813 assert(es <= PointsToNode::ArgEscape, "sanity");
2814 if (es == PointsToNode::NoEscape) {
2815 if (find_init_values_null(ptn, _igvn) > 0) {
2816 // Adding references to null object does not change escape states
2817 // since it does not escape. Also no fields are added to null object.
2818 add_java_object_edges(null_obj, false);
2819 }
2820 }
2821 Node* n = ptn->ideal_node();
2822 if (n->is_Allocate()) {
2823 // The object allocated by this Allocate node will never be
2824 // seen by an other thread. Mark it so that when it is
2825 // expanded no MemBarStoreStore is added.
2826 InitializeNode* ini = n->as_Allocate()->initialization();
2827 if (ini != nullptr)
2828 ini->set_does_not_escape();
2829 }
2830 }
2831 return true; // Finished graph construction.
2832 }
2833
2834 // Propagate GlobalEscape and ArgEscape escape states to all nodes
2835 // and check that we still have non-escaping java objects.
2836 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist,
2837 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist,
2838 bool print_method) {
2839 GrowableArray<PointsToNode*> escape_worklist;
2840 // First, put all nodes with GlobalEscape and ArgEscape states on worklist.
2841 int ptnodes_length = ptnodes_worklist.length();
2842 for (int next = 0; next < ptnodes_length; ++next) {
2843 PointsToNode* ptn = ptnodes_worklist.at(next);
2844 if (ptn->escape_state() >= PointsToNode::ArgEscape ||
2845 ptn->fields_escape_state() >= PointsToNode::ArgEscape) {
2846 escape_worklist.push(ptn);
2847 }
2848 }
2849 // Set escape states to referenced nodes (edges list).
2850 while (escape_worklist.length() > 0) {
2851 PointsToNode* ptn = escape_worklist.pop();
2852 PointsToNode::EscapeState es = ptn->escape_state();
2853 PointsToNode::EscapeState field_es = ptn->fields_escape_state();
2854 if (ptn->is_Field() && ptn->as_Field()->is_oop() &&
2855 es >= PointsToNode::ArgEscape) {
2856 // GlobalEscape or ArgEscape state of field means it has unknown value.
2857 if (add_edge(ptn, phantom_obj)) {
2858 // New edge was added
2859 add_field_uses_to_worklist(ptn->as_Field());
2860 }
2861 }
2862 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2863 PointsToNode* e = i.get();
2864 if (e->is_Arraycopy()) {
2865 assert(ptn->arraycopy_dst(), "sanity");
2866 // Propagate only fields escape state through arraycopy edge.
2867 if (e->fields_escape_state() < field_es) {
2868 set_fields_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
2869 escape_worklist.push(e);
2870 }
2871 } else if (es >= field_es) {
2872 // fields_escape_state is also set to 'es' if it is less than 'es'.
2873 if (e->escape_state() < es) {
2874 set_escape_state(e, es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
2875 escape_worklist.push(e);
2876 }
2877 } else {
2878 // Propagate field escape state.
2879 bool es_changed = false;
2880 if (e->fields_escape_state() < field_es) {
2881 set_fields_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
2882 es_changed = true;
2883 }
2884 if ((e->escape_state() < field_es) &&
2885 e->is_Field() && ptn->is_JavaObject() &&
2886 e->as_Field()->is_oop()) {
2887 // Change escape state of referenced fields.
2888 set_escape_state(e, field_es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
2889 es_changed = true;
2890 } else if (e->escape_state() < es) {
2891 set_escape_state(e, es NOT_PRODUCT(COMMA trace_propagate_message(ptn)));
2892 es_changed = true;
2893 }
2894 if (es_changed) {
2895 escape_worklist.push(e);
2896 }
2897 }
2898 if (print_method) {
2899 _compile->print_method(PHASE_EA_CONNECTION_GRAPH_PROPAGATE_ITER, 6, e->ideal_node());
2900 }
2901 }
2902 }
2903 // Remove escaped objects from non_escaped list.
2904 for (int next = non_escaped_allocs_worklist.length()-1; next >= 0 ; --next) {
2905 JavaObjectNode* ptn = non_escaped_allocs_worklist.at(next);
2906 if (ptn->escape_state() >= PointsToNode::GlobalEscape) {
2907 non_escaped_allocs_worklist.delete_at(next);
2908 }
2909 if (ptn->escape_state() == PointsToNode::NoEscape) {
2910 // Find fields in non-escaped allocations which have unknown value.
2911 find_init_values_phantom(ptn);
2912 }
2913 }
2914 return (non_escaped_allocs_worklist.length() > 0);
2915 }
2916
2917 // Add all references to JavaObject node by walking over all uses.
2918 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) {
2919 int new_edges = 0;
2920 if (populate_worklist) {
2921 // Populate _worklist by uses of jobj's uses.
2922 for (UseIterator i(jobj); i.has_next(); i.next()) {
2923 PointsToNode* use = i.get();
2924 if (use->is_Arraycopy()) {
2925 continue;
2926 }
2927 add_uses_to_worklist(use);
2928 if (use->is_Field() && use->as_Field()->is_oop()) {
2929 // Put on worklist all field's uses (loads) and
2930 // related field nodes (same base and offset).
2931 add_field_uses_to_worklist(use->as_Field());
2932 }
2933 }
2934 }
2935 for (int l = 0; l < _worklist.length(); l++) {
2936 PointsToNode* use = _worklist.at(l);
2937 if (PointsToNode::is_base_use(use)) {
2938 // Add reference from jobj to field and from field to jobj (field's base).
2939 use = PointsToNode::get_use_node(use)->as_Field();
2940 if (add_base(use->as_Field(), jobj)) {
2941 new_edges++;
2942 }
2943 continue;
2944 }
2945 assert(!use->is_JavaObject(), "sanity");
2946 if (use->is_Arraycopy()) {
2947 if (jobj == null_obj) { // null object does not have field edges
2948 continue;
2949 }
2950 // Added edge from Arraycopy node to arraycopy's source java object
2951 if (add_edge(use, jobj)) {
2952 jobj->set_arraycopy_src();
2953 new_edges++;
2954 }
2955 // and stop here.
2956 continue;
2957 }
2958 if (!add_edge(use, jobj)) {
2959 continue; // No new edge added, there was such edge already.
2960 }
2961 new_edges++;
2962 if (use->is_LocalVar()) {
2963 add_uses_to_worklist(use);
2964 if (use->arraycopy_dst()) {
2965 for (EdgeIterator i(use); i.has_next(); i.next()) {
2966 PointsToNode* e = i.get();
2967 if (e->is_Arraycopy()) {
2968 if (jobj == null_obj) { // null object does not have field edges
2969 continue;
2970 }
2971 // Add edge from arraycopy's destination java object to Arraycopy node.
2972 if (add_edge(jobj, e)) {
2973 new_edges++;
2974 jobj->set_arraycopy_dst();
2975 }
2976 }
2977 }
2978 }
2979 } else {
2980 // Added new edge to stored in field values.
2981 // Put on worklist all field's uses (loads) and
2982 // related field nodes (same base and offset).
2983 add_field_uses_to_worklist(use->as_Field());
2984 }
2985 }
2986 _worklist.clear();
2987 _in_worklist.reset();
2988 return new_edges;
2989 }
2990
2991 // Put on worklist all related field nodes.
2992 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) {
2993 assert(field->is_oop(), "sanity");
2994 int offset = field->offset();
2995 add_uses_to_worklist(field);
2996 // Loop over all bases of this field and push on worklist Field nodes
2997 // with the same offset and base (since they may reference the same field).
2998 for (BaseIterator i(field); i.has_next(); i.next()) {
2999 PointsToNode* base = i.get();
3000 add_fields_to_worklist(field, base);
3001 // Check if the base was source object of arraycopy and go over arraycopy's
3002 // destination objects since values stored to a field of source object are
3003 // accessible by uses (loads) of fields of destination objects.
3004 if (base->arraycopy_src()) {
3005 for (UseIterator j(base); j.has_next(); j.next()) {
3006 PointsToNode* arycp = j.get();
3007 if (arycp->is_Arraycopy()) {
3008 for (UseIterator k(arycp); k.has_next(); k.next()) {
3009 PointsToNode* abase = k.get();
3010 if (abase->arraycopy_dst() && abase != base) {
3011 // Look for the same arraycopy reference.
3012 add_fields_to_worklist(field, abase);
3013 }
3014 }
3015 }
3016 }
3017 }
3018 }
3019 }
3020
3021 // Put on worklist all related field nodes.
3022 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) {
3023 int offset = field->offset();
3024 if (base->is_LocalVar()) {
3025 for (UseIterator j(base); j.has_next(); j.next()) {
3026 PointsToNode* f = j.get();
3027 if (PointsToNode::is_base_use(f)) { // Field
3028 f = PointsToNode::get_use_node(f);
3029 if (f == field || !f->as_Field()->is_oop()) {
3030 continue;
3031 }
3032 int offs = f->as_Field()->offset();
3033 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
3034 add_to_worklist(f);
3035 }
3036 }
3037 }
3038 } else {
3039 assert(base->is_JavaObject(), "sanity");
3040 if (// Skip phantom_object since it is only used to indicate that
3041 // this field's content globally escapes.
3042 (base != phantom_obj) &&
3043 // null object node does not have fields.
3044 (base != null_obj)) {
3045 for (EdgeIterator i(base); i.has_next(); i.next()) {
3046 PointsToNode* f = i.get();
3047 // Skip arraycopy edge since store to destination object field
3048 // does not update value in source object field.
3049 if (f->is_Arraycopy()) {
3050 assert(base->arraycopy_dst(), "sanity");
3051 continue;
3052 }
3053 if (f == field || !f->as_Field()->is_oop()) {
3054 continue;
3055 }
3056 int offs = f->as_Field()->offset();
3057 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
3058 add_to_worklist(f);
3059 }
3060 }
3061 }
3062 }
3063 }
3064
3065 // Find fields which have unknown value.
3066 int ConnectionGraph::find_field_value(FieldNode* field) {
3067 // Escaped fields should have init value already.
3068 assert(field->escape_state() == PointsToNode::NoEscape, "sanity");
3069 int new_edges = 0;
3070 for (BaseIterator i(field); i.has_next(); i.next()) {
3071 PointsToNode* base = i.get();
3072 if (base->is_JavaObject()) {
3073 // Skip Allocate's fields which will be processed later.
3074 if (base->ideal_node()->is_Allocate()) {
3075 return 0;
3076 }
3077 assert(base == null_obj, "only null ptr base expected here");
3078 }
3079 }
3080 if (add_edge(field, phantom_obj)) {
3081 // New edge was added
3082 new_edges++;
3083 add_field_uses_to_worklist(field);
3084 }
3085 return new_edges;
3086 }
3087
3088 // Find fields initializing values for allocations.
3089 int ConnectionGraph::find_init_values_phantom(JavaObjectNode* pta) {
3090 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
3091 PointsToNode* init_val = phantom_obj;
3092 Node* alloc = pta->ideal_node();
3093
3094 // Do nothing for Allocate nodes since its fields values are
3095 // "known" unless they are initialized by arraycopy/clone.
3096 if (alloc->is_Allocate() && !pta->arraycopy_dst()) {
3097 if (alloc->as_Allocate()->in(AllocateNode::InitValue) != nullptr) {
3098 // Null-free inline type arrays are initialized with an init value instead of null
3099 init_val = ptnode_adr(alloc->as_Allocate()->in(AllocateNode::InitValue)->_idx);
3100 assert(init_val != nullptr, "init value should be registered");
3101 } else {
3102 return 0;
3103 }
3104 }
3105 // Non-escaped allocation returned from Java or runtime call has unknown values in fields.
3106 assert(pta->arraycopy_dst() || alloc->is_CallStaticJava() || init_val != phantom_obj, "sanity");
3107 #ifdef ASSERT
3108 if (alloc->is_CallStaticJava() && alloc->as_CallStaticJava()->method() == nullptr) {
3109 const char* name = alloc->as_CallStaticJava()->_name;
3110 assert(alloc->as_CallStaticJava()->is_call_to_multianewarray_stub() ||
3111 strncmp(name, "load_unknown_inline", 19) == 0 ||
3112 strncmp(name, "store_inline_type_fields_to_buf", 31) == 0, "sanity");
3113 }
3114 #endif
3115 // Non-escaped allocation returned from Java or runtime call have unknown values in fields.
3116 int new_edges = 0;
3117 for (EdgeIterator i(pta); i.has_next(); i.next()) {
3118 PointsToNode* field = i.get();
3119 if (field->is_Field() && field->as_Field()->is_oop()) {
3120 if (add_edge(field, init_val)) {
3121 // New edge was added
3122 new_edges++;
3123 add_field_uses_to_worklist(field->as_Field());
3124 }
3125 }
3126 }
3127 return new_edges;
3128 }
3129
3130 // Find fields initializing values for allocations.
3131 int ConnectionGraph::find_init_values_null(JavaObjectNode* pta, PhaseValues* phase) {
3132 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
3133 Node* alloc = pta->ideal_node();
3134 // Do nothing for Call nodes since its fields values are unknown.
3135 if (!alloc->is_Allocate() || alloc->as_Allocate()->in(AllocateNode::InitValue) != nullptr) {
3136 return 0;
3137 }
3138 InitializeNode* ini = alloc->as_Allocate()->initialization();
3139 bool visited_bottom_offset = false;
3140 GrowableArray<int> offsets_worklist;
3141 int new_edges = 0;
3142
3143 // Check if an oop field's initializing value is recorded and add
3144 // a corresponding null if field's value if it is not recorded.
3145 // Connection Graph does not record a default initialization by null
3146 // captured by Initialize node.
3147 //
3148 for (EdgeIterator i(pta); i.has_next(); i.next()) {
3149 PointsToNode* field = i.get(); // Field (AddP)
3150 if (!field->is_Field() || !field->as_Field()->is_oop()) {
3151 continue; // Not oop field
3152 }
3153 int offset = field->as_Field()->offset();
3154 if (offset == Type::OffsetBot) {
3155 if (!visited_bottom_offset) {
3156 // OffsetBot is used to reference array's element,
3157 // always add reference to null to all Field nodes since we don't
3158 // known which element is referenced.
3159 if (add_edge(field, null_obj)) {
3160 // New edge was added
3161 new_edges++;
3162 add_field_uses_to_worklist(field->as_Field());
3163 visited_bottom_offset = true;
3164 }
3165 }
3166 } else {
3167 // Check only oop fields.
3168 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type();
3169 if (adr_type->isa_rawptr()) {
3170 #ifdef ASSERT
3171 // Raw pointers are used for initializing stores so skip it
3172 // since it should be recorded already
3173 Node* base = get_addp_base(field->ideal_node());
3174 assert(adr_type->isa_rawptr() && is_captured_store_address(field->ideal_node()), "unexpected pointer type");
3175 #endif
3176 continue;
3177 }
3178 if (!offsets_worklist.contains(offset)) {
3179 offsets_worklist.append(offset);
3180 Node* value = nullptr;
3181 if (ini != nullptr) {
3182 // StoreP::value_basic_type() == T_ADDRESS
3183 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS;
3184 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase);
3185 // Make sure initializing store has the same type as this AddP.
3186 // This AddP may reference non existing field because it is on a
3187 // dead branch of bimorphic call which is not eliminated yet.
3188 if (store != nullptr && store->is_Store() &&
3189 store->as_Store()->value_basic_type() == ft) {
3190 value = store->in(MemNode::ValueIn);
3191 #ifdef ASSERT
3192 if (VerifyConnectionGraph) {
3193 // Verify that AddP already points to all objects the value points to.
3194 PointsToNode* val = ptnode_adr(value->_idx);
3195 assert((val != nullptr), "should be processed already");
3196 PointsToNode* missed_obj = nullptr;
3197 if (val->is_JavaObject()) {
3198 if (!field->points_to(val->as_JavaObject())) {
3199 missed_obj = val;
3200 }
3201 } else {
3202 if (!val->is_LocalVar() || (val->edge_count() == 0)) {
3203 tty->print_cr("----------init store has invalid value -----");
3204 store->dump();
3205 val->dump();
3206 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already");
3207 }
3208 for (EdgeIterator j(val); j.has_next(); j.next()) {
3209 PointsToNode* obj = j.get();
3210 if (obj->is_JavaObject()) {
3211 if (!field->points_to(obj->as_JavaObject())) {
3212 missed_obj = obj;
3213 break;
3214 }
3215 }
3216 }
3217 }
3218 if (missed_obj != nullptr) {
3219 tty->print_cr("----------field---------------------------------");
3220 field->dump();
3221 tty->print_cr("----------missed reference to object------------");
3222 missed_obj->dump();
3223 tty->print_cr("----------object referenced by init store-------");
3224 store->dump();
3225 val->dump();
3226 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference");
3227 }
3228 }
3229 #endif
3230 } else {
3231 // There could be initializing stores which follow allocation.
3232 // For example, a volatile field store is not collected
3233 // by Initialize node.
3234 //
3235 // Need to check for dependent loads to separate such stores from
3236 // stores which follow loads. For now, add initial value null so
3237 // that compare pointers optimization works correctly.
3238 }
3239 }
3240 if (value == nullptr) {
3241 // A field's initializing value was not recorded. Add null.
3242 if (add_edge(field, null_obj)) {
3243 // New edge was added
3244 new_edges++;
3245 add_field_uses_to_worklist(field->as_Field());
3246 }
3247 }
3248 }
3249 }
3250 }
3251 return new_edges;
3252 }
3253
3254 // Adjust scalar_replaceable state after Connection Graph is built.
3255 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj, Unique_Node_List &reducible_merges) {
3256 // A Phi 'x' is a _candidate_ to be reducible if 'can_reduce_phi(x)'
3257 // returns true. If one of the constraints in this method set 'jobj' to NSR
3258 // then the candidate Phi is discarded. If the Phi has another SR 'jobj' as
3259 // input, 'adjust_scalar_replaceable_state' will eventually be called with
3260 // that other object and the Phi will become a reducible Phi.
3261 // There could be multiple merges involving the same jobj.
3262 Unique_Node_List candidates;
3263
3264 // Search for non-escaping objects which are not scalar replaceable
3265 // and mark them to propagate the state to referenced objects.
3266
3267 for (UseIterator i(jobj); i.has_next(); i.next()) {
3268 PointsToNode* use = i.get();
3269 if (use->is_Arraycopy()) {
3270 continue;
3271 }
3272 if (use->is_Field()) {
3273 FieldNode* field = use->as_Field();
3274 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
3275 // 1. An object is not scalar replaceable if the field into which it is
3276 // stored has unknown offset (stored into unknown element of an array).
3277 if (field->offset() == Type::OffsetBot) {
3278 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored at unknown offset"));
3279 return;
3280 }
3281 for (BaseIterator i(field); i.has_next(); i.next()) {
3282 PointsToNode* base = i.get();
3283 // 2. An object is not scalar replaceable if the field into which it is
3284 // stored has multiple bases one of which is null.
3285 if ((base == null_obj) && (field->base_count() > 1)) {
3286 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with potentially null base"));
3287 return;
3288 }
3289 // 2.5. An object is not scalar replaceable if the field into which it is
3290 // stored has NSR base.
3291 if (!base->scalar_replaceable()) {
3292 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with NSR base"));
3293 return;
3294 }
3295 }
3296 }
3297 assert(use->is_Field() || use->is_LocalVar(), "sanity");
3298 // 3. An object is not scalar replaceable if it is merged with other objects
3299 // and we can't remove the merge
3300 for (EdgeIterator j(use); j.has_next(); j.next()) {
3301 PointsToNode* ptn = j.get();
3302 if (ptn->is_JavaObject() && ptn != jobj) {
3303 Node* use_n = use->ideal_node();
3304
3305 // These other local vars may point to multiple objects through a Phi
3306 // In this case we skip them and see if we can reduce the Phi.
3307 if (use_n->is_CastPP() || use_n->is_CheckCastPP()) {
3308 use_n = use_n->in(1);
3309 }
3310
3311 // If it's already a candidate or confirmed reducible merge we can skip verification
3312 if (candidates.member(use_n) || reducible_merges.member(use_n)) {
3313 continue;
3314 }
3315
3316 if (use_n->is_Phi() && can_reduce_phi(use_n->as_Phi())) {
3317 candidates.push(use_n);
3318 } else {
3319 // Mark all objects as NSR if we can't remove the merge
3320 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA trace_merged_message(ptn)));
3321 set_not_scalar_replaceable(ptn NOT_PRODUCT(COMMA trace_merged_message(jobj)));
3322 }
3323 }
3324 }
3325 if (!jobj->scalar_replaceable()) {
3326 return;
3327 }
3328 }
3329
3330 for (EdgeIterator j(jobj); j.has_next(); j.next()) {
3331 if (j.get()->is_Arraycopy()) {
3332 continue;
3333 }
3334
3335 // Non-escaping object node should point only to field nodes.
3336 FieldNode* field = j.get()->as_Field();
3337 int offset = field->as_Field()->offset();
3338
3339 // 4. An object is not scalar replaceable if it has a field with unknown
3340 // offset (array's element is accessed in loop).
3341 if (offset == Type::OffsetBot) {
3342 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "has field with unknown offset"));
3343 return;
3344 }
3345 // 5. Currently an object is not scalar replaceable if a LoadStore node
3346 // access its field since the field value is unknown after it.
3347 //
3348 Node* n = field->ideal_node();
3349
3350 // Test for an unsafe access that was parsed as maybe off heap
3351 // (with a CheckCastPP to raw memory).
3352 assert(n->is_AddP(), "expect an address computation");
3353 if (n->in(AddPNode::Base)->is_top() &&
3354 n->in(AddPNode::Address)->Opcode() == Op_CheckCastPP) {
3355 assert(n->in(AddPNode::Address)->bottom_type()->isa_rawptr(), "raw address so raw cast expected");
3356 assert(_igvn->type(n->in(AddPNode::Address)->in(1))->isa_oopptr(), "cast pattern at unsafe access expected");
3357 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is used as base of mixed unsafe access"));
3358 return;
3359 }
3360
3361 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3362 Node* u = n->fast_out(i);
3363 if (u->is_LoadStore() || (u->is_Mem() && u->as_Mem()->is_mismatched_access())) {
3364 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is used in LoadStore or mismatched access"));
3365 return;
3366 }
3367 }
3368
3369 // 6. Or the address may point to more then one object. This may produce
3370 // the false positive result (set not scalar replaceable)
3371 // since the flow-insensitive escape analysis can't separate
3372 // the case when stores overwrite the field's value from the case
3373 // when stores happened on different control branches.
3374 //
3375 // Note: it will disable scalar replacement in some cases:
3376 //
3377 // Point p[] = new Point[1];
3378 // p[0] = new Point(); // Will be not scalar replaced
3379 //
3380 // but it will save us from incorrect optimizations in next cases:
3381 //
3382 // Point p[] = new Point[1];
3383 // if ( x ) p[0] = new Point(); // Will be not scalar replaced
3384 //
3385 if (field->base_count() > 1 && candidates.size() == 0) {
3386 if (has_non_reducible_merge(field, reducible_merges)) {
3387 for (BaseIterator i(field); i.has_next(); i.next()) {
3388 PointsToNode* base = i.get();
3389 // Don't take into account LocalVar nodes which
3390 // may point to only one object which should be also
3391 // this field's base by now.
3392 if (base->is_JavaObject() && base != jobj) {
3393 // Mark all bases.
3394 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "may point to more than one object"));
3395 set_not_scalar_replaceable(base NOT_PRODUCT(COMMA "may point to more than one object"));
3396 }
3397 }
3398
3399 if (!jobj->scalar_replaceable()) {
3400 return;
3401 }
3402 }
3403 }
3404 }
3405
3406 // The candidate is truly a reducible merge only if none of the other
3407 // constraints ruled it as NSR. There could be multiple merges involving the
3408 // same jobj.
3409 assert(jobj->scalar_replaceable(), "sanity");
3410 for (uint i = 0; i < candidates.size(); i++ ) {
3411 Node* candidate = candidates.at(i);
3412 reducible_merges.push(candidate);
3413 }
3414 }
3415
3416 bool ConnectionGraph::has_non_reducible_merge(FieldNode* field, Unique_Node_List& reducible_merges) {
3417 for (BaseIterator i(field); i.has_next(); i.next()) {
3418 Node* base = i.get()->ideal_node();
3419 if (base->is_Phi() && !reducible_merges.member(base)) {
3420 return true;
3421 }
3422 }
3423 return false;
3424 }
3425
3426 void ConnectionGraph::revisit_reducible_phi_status(JavaObjectNode* jobj, Unique_Node_List& reducible_merges) {
3427 assert(jobj != nullptr && !jobj->scalar_replaceable(), "jobj should be set as NSR before calling this function.");
3428
3429 // Look for 'phis' that refer to 'jobj' as the last
3430 // remaining scalar replaceable input.
3431 uint reducible_merges_cnt = reducible_merges.size();
3432 for (uint i = 0; i < reducible_merges_cnt; i++) {
3433 Node* phi = reducible_merges.at(i);
3434
3435 // This 'Phi' will be a 'good' if it still points to
3436 // at least one scalar replaceable object. Note that 'obj'
3437 // was/should be marked as NSR before calling this function.
3438 bool good_phi = false;
3439
3440 for (uint j = 1; j < phi->req(); j++) {
3441 JavaObjectNode* phi_in_obj = unique_java_object(phi->in(j));
3442 if (phi_in_obj != nullptr && phi_in_obj->scalar_replaceable()) {
3443 good_phi = true;
3444 break;
3445 }
3446 }
3447
3448 if (!good_phi) {
3449 NOT_PRODUCT(if (TraceReduceAllocationMerges) tty->print_cr("Phi %d became non-reducible after node %d became NSR.", phi->_idx, jobj->ideal_node()->_idx);)
3450 reducible_merges.remove(i);
3451
3452 // Decrement the index because the 'remove' call above actually
3453 // moves the last entry of the list to position 'i'.
3454 i--;
3455
3456 reducible_merges_cnt--;
3457 }
3458 }
3459 }
3460
3461 // Propagate NSR (Not scalar replaceable) state.
3462 void ConnectionGraph::find_scalar_replaceable_allocs(GrowableArray<JavaObjectNode*>& jobj_worklist, Unique_Node_List &reducible_merges) {
3463 int jobj_length = jobj_worklist.length();
3464 bool found_nsr_alloc = true;
3465 while (found_nsr_alloc) {
3466 found_nsr_alloc = false;
3467 for (int next = 0; next < jobj_length; ++next) {
3468 JavaObjectNode* jobj = jobj_worklist.at(next);
3469 for (UseIterator i(jobj); (jobj->scalar_replaceable() && i.has_next()); i.next()) {
3470 PointsToNode* use = i.get();
3471 if (use->is_Field()) {
3472 FieldNode* field = use->as_Field();
3473 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
3474 assert(field->offset() != Type::OffsetBot, "sanity");
3475 for (BaseIterator i(field); i.has_next(); i.next()) {
3476 PointsToNode* base = i.get();
3477 // An object is not scalar replaceable if the field into which
3478 // it is stored has NSR base.
3479 if ((base != null_obj) && !base->scalar_replaceable()) {
3480 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is stored into field with NSR base"));
3481 // Any merge that had only 'jobj' as scalar-replaceable will now be non-reducible,
3482 // because there is no point in reducing a Phi that won't improve the number of SR
3483 // objects.
3484 revisit_reducible_phi_status(jobj, reducible_merges);
3485 found_nsr_alloc = true;
3486 break;
3487 }
3488 }
3489 } else if (use->is_LocalVar()) {
3490 Node* phi = use->ideal_node();
3491 if (phi->Opcode() == Op_Phi && reducible_merges.member(phi) && !can_reduce_phi(phi->as_Phi())) {
3492 set_not_scalar_replaceable(jobj NOT_PRODUCT(COMMA "is merged in a non-reducible phi"));
3493 reducible_merges.yank(phi);
3494 found_nsr_alloc = true;
3495 break;
3496 }
3497 }
3498 _compile->print_method(PHASE_EA_PROPAGATE_NSR_ITER, 5, jobj->ideal_node());
3499 }
3500 }
3501 }
3502 }
3503
3504 #ifdef ASSERT
3505 void ConnectionGraph::verify_connection_graph(
3506 GrowableArray<PointsToNode*>& ptnodes_worklist,
3507 GrowableArray<JavaObjectNode*>& non_escaped_allocs_worklist,
3508 GrowableArray<JavaObjectNode*>& java_objects_worklist,
3509 GrowableArray<Node*>& addp_worklist) {
3510 // Verify that graph is complete - no new edges could be added.
3511 int java_objects_length = java_objects_worklist.length();
3512 int non_escaped_length = non_escaped_allocs_worklist.length();
3513 int new_edges = 0;
3514 for (int next = 0; next < java_objects_length; ++next) {
3515 JavaObjectNode* ptn = java_objects_worklist.at(next);
3516 new_edges += add_java_object_edges(ptn, true);
3517 }
3518 assert(new_edges == 0, "graph was not complete");
3519 // Verify that escape state is final.
3520 int length = non_escaped_allocs_worklist.length();
3521 find_non_escaped_objects(ptnodes_worklist, non_escaped_allocs_worklist, /*print_method=*/ false);
3522 assert((non_escaped_length == non_escaped_allocs_worklist.length()) &&
3523 (non_escaped_length == length) &&
3524 (_worklist.length() == 0), "escape state was not final");
3525
3526 // Verify fields information.
3527 int addp_length = addp_worklist.length();
3528 for (int next = 0; next < addp_length; ++next ) {
3529 Node* n = addp_worklist.at(next);
3530 FieldNode* field = ptnode_adr(n->_idx)->as_Field();
3531 if (field->is_oop()) {
3532 // Verify that field has all bases
3533 Node* base = get_addp_base(n);
3534 PointsToNode* ptn = ptnode_adr(base->_idx);
3535 if (ptn->is_JavaObject()) {
3536 assert(field->has_base(ptn->as_JavaObject()), "sanity");
3537 } else {
3538 assert(ptn->is_LocalVar(), "sanity");
3539 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
3540 PointsToNode* e = i.get();
3541 if (e->is_JavaObject()) {
3542 assert(field->has_base(e->as_JavaObject()), "sanity");
3543 }
3544 }
3545 }
3546 // Verify that all fields have initializing values.
3547 if (field->edge_count() == 0) {
3548 tty->print_cr("----------field does not have references----------");
3549 field->dump();
3550 for (BaseIterator i(field); i.has_next(); i.next()) {
3551 PointsToNode* base = i.get();
3552 tty->print_cr("----------field has next base---------------------");
3553 base->dump();
3554 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) {
3555 tty->print_cr("----------base has fields-------------------------");
3556 for (EdgeIterator j(base); j.has_next(); j.next()) {
3557 j.get()->dump();
3558 }
3559 tty->print_cr("----------base has references---------------------");
3560 for (UseIterator j(base); j.has_next(); j.next()) {
3561 j.get()->dump();
3562 }
3563 }
3564 }
3565 for (UseIterator i(field); i.has_next(); i.next()) {
3566 i.get()->dump();
3567 }
3568 assert(field->edge_count() > 0, "sanity");
3569 }
3570 }
3571 }
3572 }
3573 #endif
3574
3575 // Optimize ideal graph.
3576 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist,
3577 GrowableArray<MemBarStoreStoreNode*>& storestore_worklist) {
3578 Compile* C = _compile;
3579 PhaseIterGVN* igvn = _igvn;
3580 if (EliminateLocks) {
3581 // Mark locks before changing ideal graph.
3582 int cnt = C->macro_count();
3583 for (int i = 0; i < cnt; i++) {
3584 Node *n = C->macro_node(i);
3585 if (n->is_AbstractLock()) { // Lock and Unlock nodes
3586 AbstractLockNode* alock = n->as_AbstractLock();
3587 if (!alock->is_non_esc_obj()) {
3588 const Type* obj_type = igvn->type(alock->obj_node());
3589 if (can_eliminate_lock(alock) && !obj_type->is_inlinetypeptr()) {
3590 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity");
3591 // The lock could be marked eliminated by lock coarsening
3592 // code during first IGVN before EA. Replace coarsened flag
3593 // to eliminate all associated locks/unlocks.
3594 #ifdef ASSERT
3595 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3");
3596 #endif
3597 alock->set_non_esc_obj();
3598 }
3599 }
3600 }
3601 }
3602 }
3603
3604 if (OptimizePtrCompare) {
3605 for (int i = 0; i < ptr_cmp_worklist.length(); i++) {
3606 Node *n = ptr_cmp_worklist.at(i);
3607 assert(n->Opcode() == Op_CmpN || n->Opcode() == Op_CmpP, "must be");
3608 const TypeInt* tcmp = optimize_ptr_compare(n->in(1), n->in(2));
3609 if (tcmp->singleton()) {
3610 Node* cmp = igvn->makecon(tcmp);
3611 #ifndef PRODUCT
3612 if (PrintOptimizePtrCompare) {
3613 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"));
3614 if (Verbose) {
3615 n->dump(1);
3616 }
3617 }
3618 #endif
3619 igvn->replace_node(n, cmp);
3620 }
3621 }
3622 }
3623
3624 // For MemBarStoreStore nodes added in library_call.cpp, check
3625 // escape status of associated AllocateNode and optimize out
3626 // MemBarStoreStore node if the allocated object never escapes.
3627 for (int i = 0; i < storestore_worklist.length(); i++) {
3628 Node* storestore = storestore_worklist.at(i);
3629 Node* alloc = storestore->in(MemBarNode::Precedent)->in(0);
3630 if (alloc->is_Allocate() && not_global_escape(alloc)) {
3631 if (alloc->in(AllocateNode::InlineType) != nullptr) {
3632 // Non-escaping inline type buffer allocations don't require a membar
3633 storestore->as_MemBar()->remove(_igvn);
3634 } else {
3635 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot);
3636 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory));
3637 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control));
3638 igvn->register_new_node_with_optimizer(mb);
3639 igvn->replace_node(storestore, mb);
3640 }
3641 }
3642 }
3643 }
3644
3645 // Atomic flat accesses on non-escaping objects can be optimized to non-atomic accesses
3646 void ConnectionGraph::optimize_flat_accesses(GrowableArray<SafePointNode*>& sfn_worklist) {
3647 PhaseIterGVN& igvn = *_igvn;
3648 bool delay = igvn.delay_transform();
3649 igvn.set_delay_transform(true);
3650 igvn.C->for_each_flat_access([&](Node* n) {
3651 Node* base = n->is_LoadFlat() ? n->as_LoadFlat()->base() : n->as_StoreFlat()->base();
3652 if (!not_global_escape(base)) {
3653 return;
3654 }
3655
3656 bool expanded;
3657 if (n->is_LoadFlat()) {
3658 expanded = n->as_LoadFlat()->expand_non_atomic(igvn);
3659 } else {
3660 expanded = n->as_StoreFlat()->expand_non_atomic(igvn);
3661 }
3662 if (expanded) {
3663 sfn_worklist.remove(n->as_SafePoint());
3664 igvn.C->remove_flat_access(n);
3665 }
3666 });
3667 igvn.set_delay_transform(delay);
3668 }
3669
3670 // Optimize objects compare.
3671 const TypeInt* ConnectionGraph::optimize_ptr_compare(Node* left, Node* right) {
3672 const TypeInt* UNKNOWN = TypeInt::CC; // [-1, 0,1]
3673 if (!OptimizePtrCompare) {
3674 return UNKNOWN;
3675 }
3676 const TypeInt* EQ = TypeInt::CC_EQ; // [0] == ZERO
3677 const TypeInt* NE = TypeInt::CC_GT; // [1] == ONE
3678
3679 PointsToNode* ptn1 = ptnode_adr(left->_idx);
3680 PointsToNode* ptn2 = ptnode_adr(right->_idx);
3681 JavaObjectNode* jobj1 = unique_java_object(left);
3682 JavaObjectNode* jobj2 = unique_java_object(right);
3683
3684 // The use of this method during allocation merge reduction may cause 'left'
3685 // or 'right' be something (e.g., a Phi) that isn't in the connection graph or
3686 // that doesn't reference an unique java object.
3687 if (ptn1 == nullptr || ptn2 == nullptr ||
3688 jobj1 == nullptr || jobj2 == nullptr) {
3689 return UNKNOWN;
3690 }
3691
3692 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity");
3693 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity");
3694
3695 // Check simple cases first.
3696 if (jobj1 != nullptr) {
3697 if (jobj1->escape_state() == PointsToNode::NoEscape) {
3698 if (jobj1 == jobj2) {
3699 // Comparing the same not escaping object.
3700 return EQ;
3701 }
3702 Node* obj = jobj1->ideal_node();
3703 // Comparing not escaping allocation.
3704 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
3705 !ptn2->points_to(jobj1)) {
3706 return NE; // This includes nullness check.
3707 }
3708 }
3709 }
3710 if (jobj2 != nullptr) {
3711 if (jobj2->escape_state() == PointsToNode::NoEscape) {
3712 Node* obj = jobj2->ideal_node();
3713 // Comparing not escaping allocation.
3714 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
3715 !ptn1->points_to(jobj2)) {
3716 return NE; // This includes nullness check.
3717 }
3718 }
3719 }
3720 if (jobj1 != nullptr && jobj1 != phantom_obj &&
3721 jobj2 != nullptr && jobj2 != phantom_obj &&
3722 jobj1->ideal_node()->is_Con() &&
3723 jobj2->ideal_node()->is_Con()) {
3724 // Klass or String constants compare. Need to be careful with
3725 // compressed pointers - compare types of ConN and ConP instead of nodes.
3726 const Type* t1 = jobj1->ideal_node()->get_ptr_type();
3727 const Type* t2 = jobj2->ideal_node()->get_ptr_type();
3728 if (t1->make_ptr() == t2->make_ptr()) {
3729 return EQ;
3730 } else {
3731 return NE;
3732 }
3733 }
3734 if (ptn1->meet(ptn2)) {
3735 return UNKNOWN; // Sets are not disjoint
3736 }
3737
3738 // Sets are disjoint.
3739 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj);
3740 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj);
3741 bool set1_has_null_ptr = ptn1->points_to(null_obj);
3742 bool set2_has_null_ptr = ptn2->points_to(null_obj);
3743 if ((set1_has_unknown_ptr && set2_has_null_ptr) ||
3744 (set2_has_unknown_ptr && set1_has_null_ptr)) {
3745 // Check nullness of unknown object.
3746 return UNKNOWN;
3747 }
3748
3749 // Disjointness by itself is not sufficient since
3750 // alias analysis is not complete for escaped objects.
3751 // Disjoint sets are definitely unrelated only when
3752 // at least one set has only not escaping allocations.
3753 if (!set1_has_unknown_ptr && !set1_has_null_ptr) {
3754 if (ptn1->non_escaping_allocation()) {
3755 return NE;
3756 }
3757 }
3758 if (!set2_has_unknown_ptr && !set2_has_null_ptr) {
3759 if (ptn2->non_escaping_allocation()) {
3760 return NE;
3761 }
3762 }
3763 return UNKNOWN;
3764 }
3765
3766 // Connection Graph construction functions.
3767
3768 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) {
3769 PointsToNode* ptadr = _nodes.at(n->_idx);
3770 if (ptadr != nullptr) {
3771 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity");
3772 return;
3773 }
3774 Compile* C = _compile;
3775 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es);
3776 map_ideal_node(n, ptadr);
3777 }
3778
3779 PointsToNode* ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) {
3780 PointsToNode* ptadr = _nodes.at(n->_idx);
3781 if (ptadr != nullptr) {
3782 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity");
3783 return ptadr;
3784 }
3785 Compile* C = _compile;
3786 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es);
3787 map_ideal_node(n, ptadr);
3788 return ptadr;
3789 }
3790
3791 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) {
3792 PointsToNode* ptadr = _nodes.at(n->_idx);
3793 if (ptadr != nullptr) {
3794 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity");
3795 return;
3796 }
3797 bool unsafe = false;
3798 bool is_oop = is_oop_field(n, offset, &unsafe);
3799 if (unsafe) {
3800 es = PointsToNode::GlobalEscape;
3801 }
3802 Compile* C = _compile;
3803 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop);
3804 map_ideal_node(n, field);
3805 }
3806
3807 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es,
3808 PointsToNode* src, PointsToNode* dst) {
3809 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar");
3810 assert((src != null_obj) && (dst != null_obj), "not for ConP null");
3811 PointsToNode* ptadr = _nodes.at(n->_idx);
3812 if (ptadr != nullptr) {
3813 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity");
3814 return;
3815 }
3816 Compile* C = _compile;
3817 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es);
3818 map_ideal_node(n, ptadr);
3819 // Add edge from arraycopy node to source object.
3820 (void)add_edge(ptadr, src);
3821 src->set_arraycopy_src();
3822 // Add edge from destination object to arraycopy node.
3823 (void)add_edge(dst, ptadr);
3824 dst->set_arraycopy_dst();
3825 }
3826
3827 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) {
3828 const Type* adr_type = n->as_AddP()->bottom_type();
3829 int field_offset = adr_type->isa_aryptr() ? adr_type->isa_aryptr()->field_offset().get() : Type::OffsetBot;
3830 BasicType bt = T_INT;
3831 if (offset == Type::OffsetBot && field_offset == Type::OffsetBot) {
3832 // Check only oop fields.
3833 if (!adr_type->isa_aryptr() ||
3834 adr_type->isa_aryptr()->elem() == Type::BOTTOM ||
3835 adr_type->isa_aryptr()->elem()->make_oopptr() != nullptr) {
3836 // OffsetBot is used to reference array's element. Ignore first AddP.
3837 if (find_second_addp(n, n->in(AddPNode::Base)) == nullptr) {
3838 bt = T_OBJECT;
3839 }
3840 }
3841 } else if (offset != oopDesc::klass_offset_in_bytes()) {
3842 if (adr_type->isa_instptr()) {
3843 ciField* field = _compile->alias_type(adr_type->is_ptr())->field();
3844 if (field != nullptr) {
3845 bt = field->layout_type();
3846 } else {
3847 // Check for unsafe oop field access
3848 if (has_oop_node_outs(n)) {
3849 bt = T_OBJECT;
3850 (*unsafe) = true;
3851 }
3852 }
3853 } else if (adr_type->isa_aryptr()) {
3854 if (offset == arrayOopDesc::length_offset_in_bytes()) {
3855 // Ignore array length load.
3856 } else if (find_second_addp(n, n->in(AddPNode::Base)) != nullptr) {
3857 // Ignore first AddP.
3858 } else {
3859 const Type* elemtype = adr_type->is_aryptr()->elem();
3860 if (adr_type->is_aryptr()->is_flat() && field_offset != Type::OffsetBot) {
3861 ciInlineKlass* vk = elemtype->inline_klass();
3862 field_offset += vk->payload_offset();
3863 ciField* field = vk->get_field_by_offset(field_offset, false);
3864 if (field != nullptr) {
3865 bt = field->layout_type();
3866 } else {
3867 assert(field_offset == vk->payload_offset() + vk->null_marker_offset_in_payload(), "no field or null marker of %s at offset %d", vk->name()->as_utf8(), field_offset);
3868 bt = T_BOOLEAN;
3869 }
3870 } else {
3871 bt = elemtype->array_element_basic_type();
3872 }
3873 }
3874 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) {
3875 // Allocation initialization, ThreadLocal field access, unsafe access
3876 if (has_oop_node_outs(n)) {
3877 bt = T_OBJECT;
3878 }
3879 }
3880 }
3881 // Note: T_NARROWOOP is not classed as a real reference type
3882 bool res = (is_reference_type(bt) || bt == T_NARROWOOP);
3883 assert(!has_oop_node_outs(n) || res, "sanity: AddP has oop outs, needs to be treated as oop field");
3884 return res;
3885 }
3886
3887 bool ConnectionGraph::has_oop_node_outs(Node* n) {
3888 return n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
3889 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
3890 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN) ||
3891 BarrierSet::barrier_set()->barrier_set_c2()->escape_has_out_with_unsafe_object(n);
3892 }
3893
3894 // Returns unique pointed java object or null.
3895 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) const {
3896 // If the node was created after the escape computation we can't answer.
3897 uint idx = n->_idx;
3898 if (idx >= nodes_size()) {
3899 return nullptr;
3900 }
3901 PointsToNode* ptn = ptnode_adr(idx);
3902 if (ptn == nullptr) {
3903 return nullptr;
3904 }
3905 if (ptn->is_JavaObject()) {
3906 return ptn->as_JavaObject();
3907 }
3908 assert(ptn->is_LocalVar(), "sanity");
3909 // Check all java objects it points to.
3910 JavaObjectNode* jobj = nullptr;
3911 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
3912 PointsToNode* e = i.get();
3913 if (e->is_JavaObject()) {
3914 if (jobj == nullptr) {
3915 jobj = e->as_JavaObject();
3916 } else if (jobj != e) {
3917 return nullptr;
3918 }
3919 }
3920 }
3921 return jobj;
3922 }
3923
3924 // Return true if this node points only to non-escaping allocations.
3925 bool PointsToNode::non_escaping_allocation() {
3926 if (is_JavaObject()) {
3927 Node* n = ideal_node();
3928 if (n->is_Allocate() || n->is_CallStaticJava()) {
3929 return (escape_state() == PointsToNode::NoEscape);
3930 } else {
3931 return false;
3932 }
3933 }
3934 assert(is_LocalVar(), "sanity");
3935 // Check all java objects it points to.
3936 for (EdgeIterator i(this); i.has_next(); i.next()) {
3937 PointsToNode* e = i.get();
3938 if (e->is_JavaObject()) {
3939 Node* n = e->ideal_node();
3940 if ((e->escape_state() != PointsToNode::NoEscape) ||
3941 !(n->is_Allocate() || n->is_CallStaticJava())) {
3942 return false;
3943 }
3944 }
3945 }
3946 return true;
3947 }
3948
3949 // Return true if we know the node does not escape globally.
3950 bool ConnectionGraph::not_global_escape(Node *n) {
3951 assert(!_collecting, "should not call during graph construction");
3952 // If the node was created after the escape computation we can't answer.
3953 uint idx = n->_idx;
3954 if (idx >= nodes_size()) {
3955 return false;
3956 }
3957 PointsToNode* ptn = ptnode_adr(idx);
3958 if (ptn == nullptr) {
3959 return false; // not in congraph (e.g. ConI)
3960 }
3961 PointsToNode::EscapeState es = ptn->escape_state();
3962 // If we have already computed a value, return it.
3963 if (es >= PointsToNode::GlobalEscape) {
3964 return false;
3965 }
3966 if (ptn->is_JavaObject()) {
3967 return true; // (es < PointsToNode::GlobalEscape);
3968 }
3969 assert(ptn->is_LocalVar(), "sanity");
3970 // Check all java objects it points to.
3971 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
3972 if (i.get()->escape_state() >= PointsToNode::GlobalEscape) {
3973 return false;
3974 }
3975 }
3976 return true;
3977 }
3978
3979 // Return true if locked object does not escape globally
3980 // and locked code region (identified by BoxLockNode) is balanced:
3981 // all compiled code paths have corresponding Lock/Unlock pairs.
3982 bool ConnectionGraph::can_eliminate_lock(AbstractLockNode* alock) {
3983 if (alock->is_balanced() && not_global_escape(alock->obj_node())) {
3984 if (EliminateNestedLocks) {
3985 // We can mark whole locking region as Local only when only
3986 // one object is used for locking.
3987 alock->box_node()->as_BoxLock()->set_local();
3988 }
3989 return true;
3990 }
3991 return false;
3992 }
3993
3994 // Helper functions
3995
3996 // Return true if this node points to specified node or nodes it points to.
3997 bool PointsToNode::points_to(JavaObjectNode* ptn) const {
3998 if (is_JavaObject()) {
3999 return (this == ptn);
4000 }
4001 assert(is_LocalVar() || is_Field(), "sanity");
4002 for (EdgeIterator i(this); i.has_next(); i.next()) {
4003 if (i.get() == ptn) {
4004 return true;
4005 }
4006 }
4007 return false;
4008 }
4009
4010 // Return true if one node points to an other.
4011 bool PointsToNode::meet(PointsToNode* ptn) {
4012 if (this == ptn) {
4013 return true;
4014 } else if (ptn->is_JavaObject()) {
4015 return this->points_to(ptn->as_JavaObject());
4016 } else if (this->is_JavaObject()) {
4017 return ptn->points_to(this->as_JavaObject());
4018 }
4019 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity");
4020 int ptn_count = ptn->edge_count();
4021 for (EdgeIterator i(this); i.has_next(); i.next()) {
4022 PointsToNode* this_e = i.get();
4023 for (int j = 0; j < ptn_count; j++) {
4024 if (this_e == ptn->edge(j)) {
4025 return true;
4026 }
4027 }
4028 }
4029 return false;
4030 }
4031
4032 #ifdef ASSERT
4033 // Return true if bases point to this java object.
4034 bool FieldNode::has_base(JavaObjectNode* jobj) const {
4035 for (BaseIterator i(this); i.has_next(); i.next()) {
4036 if (i.get() == jobj) {
4037 return true;
4038 }
4039 }
4040 return false;
4041 }
4042 #endif
4043
4044 bool ConnectionGraph::is_captured_store_address(Node* addp) {
4045 // Handle simple case first.
4046 assert(_igvn->type(addp)->isa_oopptr() == nullptr, "should be raw access");
4047 if (addp->in(AddPNode::Address)->is_Proj() && addp->in(AddPNode::Address)->in(0)->is_Allocate()) {
4048 return true;
4049 } else if (addp->in(AddPNode::Address)->is_Phi()) {
4050 for (DUIterator_Fast imax, i = addp->fast_outs(imax); i < imax; i++) {
4051 Node* addp_use = addp->fast_out(i);
4052 if (addp_use->is_Store()) {
4053 for (DUIterator_Fast jmax, j = addp_use->fast_outs(jmax); j < jmax; j++) {
4054 if (addp_use->fast_out(j)->is_Initialize()) {
4055 return true;
4056 }
4057 }
4058 }
4059 }
4060 }
4061 return false;
4062 }
4063
4064 int ConnectionGraph::address_offset(Node* adr, PhaseValues* phase) {
4065 const Type *adr_type = phase->type(adr);
4066 if (adr->is_AddP() && adr_type->isa_oopptr() == nullptr && is_captured_store_address(adr)) {
4067 // We are computing a raw address for a store captured by an Initialize
4068 // compute an appropriate address type. AddP cases #3 and #5 (see below).
4069 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
4070 assert(offs != Type::OffsetBot ||
4071 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
4072 "offset must be a constant or it is initialization of array");
4073 return offs;
4074 }
4075 return adr_type->is_ptr()->flat_offset();
4076 }
4077
4078 Node* ConnectionGraph::get_addp_base(Node *addp) {
4079 assert(addp->is_AddP(), "must be AddP");
4080 //
4081 // AddP cases for Base and Address inputs:
4082 // case #1. Direct object's field reference:
4083 // Allocate
4084 // |
4085 // Proj #5 ( oop result )
4086 // |
4087 // CheckCastPP (cast to instance type)
4088 // | |
4089 // AddP ( base == address )
4090 //
4091 // case #2. Indirect object's field reference:
4092 // Phi
4093 // |
4094 // CastPP (cast to instance type)
4095 // | |
4096 // AddP ( base == address )
4097 //
4098 // case #3. Raw object's field reference for Initialize node.
4099 // Could have an additional Phi merging multiple allocations.
4100 // Allocate
4101 // |
4102 // Proj #5 ( oop result )
4103 // top |
4104 // \ |
4105 // AddP ( base == top )
4106 //
4107 // case #4. Array's element reference:
4108 // {CheckCastPP | CastPP}
4109 // | | |
4110 // | AddP ( array's element offset )
4111 // | |
4112 // AddP ( array's offset )
4113 //
4114 // case #5. Raw object's field reference for arraycopy stub call:
4115 // The inline_native_clone() case when the arraycopy stub is called
4116 // after the allocation before Initialize and CheckCastPP nodes.
4117 // Allocate
4118 // |
4119 // Proj #5 ( oop result )
4120 // | |
4121 // AddP ( base == address )
4122 //
4123 // case #6. Constant Pool, ThreadLocal, CastX2P, Klass, OSR buffer buf or
4124 // Raw object's field reference:
4125 // {ConP, ThreadLocal, CastX2P, raw Load, Parm0}
4126 // top |
4127 // \ |
4128 // AddP ( base == top )
4129 //
4130 // case #7. Klass's field reference.
4131 // LoadKlass
4132 // | |
4133 // AddP ( base == address )
4134 //
4135 // case #8. narrow Klass's field reference.
4136 // LoadNKlass
4137 // |
4138 // DecodeN
4139 // | |
4140 // AddP ( base == address )
4141 //
4142 // case #9. Mixed unsafe access
4143 // {instance}
4144 // |
4145 // CheckCastPP (raw)
4146 // top |
4147 // \ |
4148 // AddP ( base == top )
4149 //
4150 // case #10. Klass fetched with
4151 // LibraryCallKit::load_*_refined_array_klass()
4152 // which has en extra Phi.
4153 // LoadKlass LoadKlass
4154 // | |
4155 // CastPP CastPP
4156 // \ /
4157 // Phi
4158 // top |
4159 // \ |
4160 // AddP ( base == top )
4161 //
4162 Node *base = addp->in(AddPNode::Base);
4163 if (base->uncast()->is_top()) { // The AddP case #3, #6, #9, and #10.
4164 base = addp->in(AddPNode::Address);
4165 while (base->is_AddP()) {
4166 // Case #6 (unsafe access) may have several chained AddP nodes.
4167 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only");
4168 base = base->in(AddPNode::Address);
4169 }
4170 if (base->Opcode() == Op_CheckCastPP &&
4171 base->bottom_type()->isa_rawptr() &&
4172 _igvn->type(base->in(1))->isa_oopptr()) {
4173 base = base->in(1); // Case #9
4174 } else {
4175 // Case #3, #6, and #10
4176 Node* uncast_base = base->uncast();
4177 int opcode = uncast_base->Opcode();
4178 assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
4179 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
4180 (_igvn->C->is_osr_compilation() && uncast_base->is_Parm() && uncast_base->as_Parm()->_con == TypeFunc::Parms)||
4181 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != nullptr)) ||
4182 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_klassptr() != nullptr)) ||
4183 is_captured_store_address(addp) ||
4184 is_load_array_klass_related(uncast_base), "sanity");
4185 }
4186 }
4187 return base;
4188 }
4189
4190 #ifdef ASSERT
4191 // Case #10
4192 bool ConnectionGraph::is_load_array_klass_related(const Node* uncast_base) {
4193 if (!uncast_base->is_Phi() || uncast_base->req() != 3) {
4194 return false;
4195 }
4196 Node* in1 = uncast_base->in(1);
4197 Node* in2 = uncast_base->in(2);
4198 return in1->uncast()->Opcode() == Op_LoadKlass &&
4199 in2->uncast()->Opcode() == Op_LoadKlass;
4200 }
4201 #endif
4202
4203 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) {
4204 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
4205 Node* addp2 = addp->raw_out(0);
4206 if (addp->outcnt() == 1 && addp2->is_AddP() &&
4207 addp2->in(AddPNode::Base) == n &&
4208 addp2->in(AddPNode::Address) == addp) {
4209 assert(addp->in(AddPNode::Base) == n, "expecting the same base");
4210 //
4211 // Find array's offset to push it on worklist first and
4212 // as result process an array's element offset first (pushed second)
4213 // to avoid CastPP for the array's offset.
4214 // Otherwise the inserted CastPP (LocalVar) will point to what
4215 // the AddP (Field) points to. Which would be wrong since
4216 // the algorithm expects the CastPP has the same point as
4217 // as AddP's base CheckCastPP (LocalVar).
4218 //
4219 // ArrayAllocation
4220 // |
4221 // CheckCastPP
4222 // |
4223 // memProj (from ArrayAllocation CheckCastPP)
4224 // | ||
4225 // | || Int (element index)
4226 // | || | ConI (log(element size))
4227 // | || | /
4228 // | || LShift
4229 // | || /
4230 // | AddP (array's element offset)
4231 // | |
4232 // | | ConI (array's offset: #12(32-bits) or #24(64-bits))
4233 // | / /
4234 // AddP (array's offset)
4235 // |
4236 // Load/Store (memory operation on array's element)
4237 //
4238 return addp2;
4239 }
4240 return nullptr;
4241 }
4242
4243 //
4244 // Adjust the type and inputs of an AddP which computes the
4245 // address of a field of an instance
4246 //
4247 bool ConnectionGraph::split_AddP(Node *addp, Node *base) {
4248 PhaseGVN* igvn = _igvn;
4249 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
4250 assert(base_t != nullptr && base_t->is_known_instance(), "expecting instance oopptr");
4251 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
4252 if (t == nullptr) {
4253 // We are computing a raw address for a store captured by an Initialize
4254 // compute an appropriate address type (cases #3 and #5).
4255 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
4256 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
4257 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
4258 assert(offs != Type::OffsetBot, "offset must be a constant");
4259 if (base_t->isa_aryptr() != nullptr) {
4260 // In the case of a flat inline type array, each field has its
4261 // own slice so we need to extract the field being accessed from
4262 // the address computation
4263 t = base_t->isa_aryptr()->add_field_offset_and_offset(offs)->is_oopptr();
4264 } else {
4265 t = base_t->add_offset(offs)->is_oopptr();
4266 }
4267 }
4268 int inst_id = base_t->instance_id();
4269 assert(!t->is_known_instance() || t->instance_id() == inst_id,
4270 "old type must be non-instance or match new type");
4271
4272 // The type 't' could be subclass of 'base_t'.
4273 // As result t->offset() could be large then base_t's size and it will
4274 // cause the failure in add_offset() with narrow oops since TypeOopPtr()
4275 // constructor verifies correctness of the offset.
4276 //
4277 // It could happened on subclass's branch (from the type profiling
4278 // inlining) which was not eliminated during parsing since the exactness
4279 // of the allocation type was not propagated to the subclass type check.
4280 //
4281 // Or the type 't' could be not related to 'base_t' at all.
4282 // It could happen when CHA type is different from MDO type on a dead path
4283 // (for example, from instanceof check) which is not collapsed during parsing.
4284 //
4285 // Do nothing for such AddP node and don't process its users since
4286 // this code branch will go away.
4287 //
4288 if (!t->is_known_instance() &&
4289 !base_t->maybe_java_subtype_of(t)) {
4290 return false; // bail out
4291 }
4292 const TypePtr* tinst = base_t->add_offset(t->offset());
4293 if (tinst->isa_aryptr() && t->isa_aryptr()) {
4294 // In the case of a flat inline type array, each field has its
4295 // own slice so we need to keep track of the field being accessed.
4296 tinst = tinst->is_aryptr()->with_field_offset(t->is_aryptr()->field_offset().get());
4297 // Keep array properties (not flat/null-free)
4298 tinst = tinst->is_aryptr()->update_properties(t->is_aryptr());
4299 if (tinst == nullptr) {
4300 return false; // Skip dead path with inconsistent properties
4301 }
4302 }
4303
4304 // Do NOT remove the next line: ensure a new alias index is allocated
4305 // for the instance type. Note: C++ will not remove it since the call
4306 // has side effect.
4307 int alias_idx = _compile->get_alias_index(tinst);
4308 igvn->set_type(addp, tinst);
4309 // record the allocation in the node map
4310 set_map(addp, get_map(base->_idx));
4311 // Set addp's Base and Address to 'base'.
4312 Node *abase = addp->in(AddPNode::Base);
4313 Node *adr = addp->in(AddPNode::Address);
4314 if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
4315 adr->in(0)->_idx == (uint)inst_id) {
4316 // Skip AddP cases #3 and #5.
4317 } else {
4318 assert(!abase->is_top(), "sanity"); // AddP case #3
4319 if (abase != base) {
4320 igvn->hash_delete(addp);
4321 addp->set_req(AddPNode::Base, base);
4322 if (abase == adr) {
4323 addp->set_req(AddPNode::Address, base);
4324 } else {
4325 // AddP case #4 (adr is array's element offset AddP node)
4326 #ifdef ASSERT
4327 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
4328 assert(adr->is_AddP() && atype != nullptr &&
4329 atype->instance_id() == inst_id, "array's element offset should be processed first");
4330 #endif
4331 }
4332 igvn->hash_insert(addp);
4333 }
4334 }
4335 // Put on IGVN worklist since at least addp's type was changed above.
4336 record_for_optimizer(addp);
4337 return true;
4338 }
4339
4340 //
4341 // Create a new version of orig_phi if necessary. Returns either the newly
4342 // created phi or an existing phi. Sets create_new to indicate whether a new
4343 // phi was created. Cache the last newly created phi in the node map.
4344 //
4345 PhiNode* ConnectionGraph::create_split_phi(PhiNode* orig_phi, int alias_idx, Unique_Node_List& orig_phi_worklist, bool& new_created) {
4346 Compile *C = _compile;
4347 PhaseGVN* igvn = _igvn;
4348 new_created = false;
4349 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
4350 // nothing to do if orig_phi is bottom memory or matches alias_idx
4351 if (phi_alias_idx == alias_idx) {
4352 return orig_phi;
4353 }
4354 // Have we recently created a Phi for this alias index?
4355 PhiNode *result = get_map_phi(orig_phi->_idx);
4356 if (result != nullptr && C->get_alias_index(result->adr_type()) == alias_idx) {
4357 return result;
4358 }
4359 // Previous check may fail when the same wide memory Phi was split into Phis
4360 // for different memory slices. Search all Phis for this region.
4361 if (result != nullptr) {
4362 Node* region = orig_phi->in(0);
4363 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
4364 Node* phi = region->fast_out(i);
4365 if (phi->is_Phi() &&
4366 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
4367 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
4368 return phi->as_Phi();
4369 }
4370 }
4371 }
4372 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) {
4373 if (C->do_escape_analysis() == true && !C->failing()) {
4374 // Retry compilation without escape analysis.
4375 // If this is the first failure, the sentinel string will "stick"
4376 // to the Compile object, and the C2Compiler will see it and retry.
4377 C->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
4378 }
4379 return nullptr;
4380 }
4381 orig_phi_worklist.push(orig_phi);
4382 const TypePtr *atype = C->get_adr_type(alias_idx);
4383 result = PhiNode::make(orig_phi->in(0), nullptr, Type::MEMORY, atype);
4384 C->copy_node_notes_to(result, orig_phi);
4385 igvn->set_type(result, result->bottom_type());
4386 record_for_optimizer(result);
4387 set_map(orig_phi, result);
4388 new_created = true;
4389 return result;
4390 }
4391
4392 //
4393 // Return a new version of Memory Phi "orig_phi" with the inputs having the
4394 // specified alias index.
4395 //
4396 PhiNode* ConnectionGraph::split_memory_phi(PhiNode* orig_phi, int alias_idx, Unique_Node_List& orig_phi_worklist, uint rec_depth) {
4397 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
4398 Compile *C = _compile;
4399 PhaseGVN* igvn = _igvn;
4400 bool new_phi_created;
4401 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created);
4402 if (!new_phi_created) {
4403 return result;
4404 }
4405 Unique_Node_List phi_list;
4406 GrowableArray<uint> cur_input;
4407 PhiNode *phi = orig_phi;
4408 uint idx = 1;
4409 bool finished = false;
4410 while(!finished) {
4411 while (idx < phi->req()) {
4412 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, rec_depth + 1);
4413 if (mem != nullptr && mem->is_Phi()) {
4414 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created);
4415 if (new_phi_created) {
4416 // found an phi for which we created a new split, push current one on worklist and begin
4417 // processing new one
4418 phi_list.push(phi);
4419 cur_input.push(idx);
4420 phi = mem->as_Phi();
4421 result = newphi;
4422 idx = 1;
4423 continue;
4424 } else {
4425 mem = newphi;
4426 }
4427 }
4428 if (C->failing()) {
4429 return nullptr;
4430 }
4431 result->set_req(idx++, mem);
4432 }
4433 #ifdef ASSERT
4434 // verify that the new Phi has an input for each input of the original
4435 assert( phi->req() == result->req(), "must have same number of inputs.");
4436 assert( result->in(0) != nullptr && result->in(0) == phi->in(0), "regions must match");
4437 #endif
4438 // Check if all new phi's inputs have specified alias index.
4439 // Otherwise use old phi.
4440 for (uint i = 1; i < phi->req(); i++) {
4441 Node* in = result->in(i);
4442 assert((phi->in(i) == nullptr) == (in == nullptr), "inputs must correspond.");
4443 }
4444 // we have finished processing a Phi, see if there are any more to do
4445 finished = (phi_list.size() == 0);
4446 if (!finished) {
4447 phi = phi_list.pop()->as_Phi();
4448 idx = cur_input.pop();
4449 PhiNode *prev_result = get_map_phi(phi->_idx);
4450 prev_result->set_req(idx++, result);
4451 result = prev_result;
4452 }
4453 }
4454 return result;
4455 }
4456
4457 //
4458 // The next methods are derived from methods in MemNode.
4459 //
4460 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
4461 Node *mem = mmem;
4462 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
4463 // means an array I have not precisely typed yet. Do not do any
4464 // alias stuff with it any time soon.
4465 if (toop->base() != Type::AnyPtr &&
4466 !(toop->isa_instptr() &&
4467 toop->is_instptr()->instance_klass()->is_java_lang_Object() &&
4468 toop->offset() == Type::OffsetBot)) {
4469 mem = mmem->memory_at(alias_idx);
4470 // Update input if it is progress over what we have now
4471 }
4472 return mem;
4473 }
4474
4475 //
4476 // Move memory users to their memory slices.
4477 //
4478 void ConnectionGraph::move_inst_mem(Node* n, Unique_Node_List& orig_phis) {
4479 Compile* C = _compile;
4480 PhaseGVN* igvn = _igvn;
4481 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
4482 assert(tp != nullptr, "ptr type");
4483 int alias_idx = C->get_alias_index(tp);
4484 int general_idx = C->get_general_index(alias_idx);
4485
4486 // Move users first
4487 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
4488 Node* use = n->fast_out(i);
4489 if (use->is_MergeMem()) {
4490 MergeMemNode* mmem = use->as_MergeMem();
4491 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
4492 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
4493 continue; // Nothing to do
4494 }
4495 // Replace previous general reference to mem node.
4496 uint orig_uniq = C->unique();
4497 Node* m = find_inst_mem(n, general_idx, orig_phis);
4498 assert(orig_uniq == C->unique(), "no new nodes");
4499 mmem->set_memory_at(general_idx, m);
4500 --imax;
4501 --i;
4502 } else if (use->is_MemBar()) {
4503 assert(!use->is_Initialize(), "initializing stores should not be moved");
4504 if (use->req() > MemBarNode::Precedent &&
4505 use->in(MemBarNode::Precedent) == n) {
4506 // Don't move related membars.
4507 record_for_optimizer(use);
4508 continue;
4509 }
4510 tp = use->as_MemBar()->adr_type()->isa_ptr();
4511 if ((tp != nullptr && C->get_alias_index(tp) == alias_idx) ||
4512 alias_idx == general_idx) {
4513 continue; // Nothing to do
4514 }
4515 // Move to general memory slice.
4516 uint orig_uniq = C->unique();
4517 Node* m = find_inst_mem(n, general_idx, orig_phis);
4518 assert(orig_uniq == C->unique(), "no new nodes");
4519 igvn->hash_delete(use);
4520 imax -= use->replace_edge(n, m, igvn);
4521 igvn->hash_insert(use);
4522 record_for_optimizer(use);
4523 --i;
4524 #ifdef ASSERT
4525 } else if (use->is_Mem()) {
4526 // Memory nodes should have new memory input.
4527 tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
4528 assert(tp != nullptr, "ptr type");
4529 int idx = C->get_alias_index(tp);
4530 assert(get_map(use->_idx) != nullptr || idx == alias_idx,
4531 "Following memory nodes should have new memory input or be on the same memory slice");
4532 } else if (use->is_Phi()) {
4533 // Phi nodes should be split and moved already.
4534 tp = use->as_Phi()->adr_type()->isa_ptr();
4535 assert(tp != nullptr, "ptr type");
4536 int idx = C->get_alias_index(tp);
4537 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
4538 } else {
4539 use->dump();
4540 assert(false, "should not be here");
4541 #endif
4542 }
4543 }
4544 }
4545
4546 //
4547 // Search memory chain of "mem" to find a MemNode whose address
4548 // is the specified alias index.
4549 //
4550 #define FIND_INST_MEM_RECURSION_DEPTH_LIMIT 1000
4551 Node* ConnectionGraph::find_inst_mem(Node* orig_mem, int alias_idx, Unique_Node_List& orig_phis, uint rec_depth) {
4552 if (rec_depth > FIND_INST_MEM_RECURSION_DEPTH_LIMIT) {
4553 _compile->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
4554 return nullptr;
4555 }
4556 if (orig_mem == nullptr) {
4557 return orig_mem;
4558 }
4559 Compile* C = _compile;
4560 PhaseGVN* igvn = _igvn;
4561 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
4562 bool is_instance = (toop != nullptr) && toop->is_known_instance();
4563 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
4564 Node *prev = nullptr;
4565 Node *result = orig_mem;
4566 while (prev != result) {
4567 prev = result;
4568 if (result == start_mem) {
4569 break; // hit one of our sentinels
4570 }
4571 if (result->is_Mem()) {
4572 const Type *at = igvn->type(result->in(MemNode::Address));
4573 if (at == Type::TOP) {
4574 break; // Dead
4575 }
4576 assert (at->isa_ptr() != nullptr, "pointer type required.");
4577 int idx = C->get_alias_index(at->is_ptr());
4578 if (idx == alias_idx) {
4579 break; // Found
4580 }
4581 if (!is_instance && (at->isa_oopptr() == nullptr ||
4582 !at->is_oopptr()->is_known_instance())) {
4583 break; // Do not skip store to general memory slice.
4584 }
4585 result = result->in(MemNode::Memory);
4586 }
4587 if (!is_instance) {
4588 continue; // don't search further for non-instance types
4589 }
4590 // skip over a call which does not affect this memory slice
4591 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
4592 Node *proj_in = result->in(0);
4593 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
4594 break; // hit one of our sentinels
4595 } else if (proj_in->is_Call()) {
4596 // ArrayCopy node processed here as well
4597 CallNode *call = proj_in->as_Call();
4598 if (!call->may_modify(toop, igvn)) {
4599 result = call->in(TypeFunc::Memory);
4600 }
4601 } else if (proj_in->is_Initialize()) {
4602 AllocateNode* alloc = proj_in->as_Initialize()->allocation();
4603 // Stop if this is the initialization for the object instance which
4604 // which contains this memory slice, otherwise skip over it.
4605 if (alloc == nullptr || alloc->_idx != (uint)toop->instance_id()) {
4606 result = proj_in->in(TypeFunc::Memory);
4607 } else if (C->get_alias_index(result->adr_type()) != alias_idx) {
4608 assert(C->get_general_index(alias_idx) == C->get_alias_index(result->adr_type()), "should be projection for the same field/array element");
4609 result = get_map(result->_idx);
4610 assert(result != nullptr, "new projection should have been allocated");
4611 break;
4612 }
4613 } else if (proj_in->is_MemBar()) {
4614 // Check if there is an array copy for a clone
4615 // Step over GC barrier when ReduceInitialCardMarks is disabled
4616 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
4617 Node* control_proj_ac = bs->step_over_gc_barrier(proj_in->in(0));
4618
4619 if (control_proj_ac->is_Proj() && control_proj_ac->in(0)->is_ArrayCopy()) {
4620 // Stop if it is a clone
4621 ArrayCopyNode* ac = control_proj_ac->in(0)->as_ArrayCopy();
4622 if (ac->may_modify(toop, igvn)) {
4623 break;
4624 }
4625 }
4626 result = proj_in->in(TypeFunc::Memory);
4627 } else if (proj_in->is_LoadFlat()) {
4628 result = proj_in->in(TypeFunc::Memory);
4629 }
4630 } else if (result->is_MergeMem()) {
4631 MergeMemNode *mmem = result->as_MergeMem();
4632 result = step_through_mergemem(mmem, alias_idx, toop);
4633 if (result == mmem->base_memory()) {
4634 // Didn't find instance memory, search through general slice recursively.
4635 result = mmem->memory_at(C->get_general_index(alias_idx));
4636 result = find_inst_mem(result, alias_idx, orig_phis, rec_depth + 1);
4637 if (C->failing()) {
4638 return nullptr;
4639 }
4640 mmem->set_memory_at(alias_idx, result);
4641 }
4642 } else if (result->is_Phi() &&
4643 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
4644 Node *un = result->as_Phi()->unique_input(igvn);
4645 if (un != nullptr) {
4646 orig_phis.push(result);
4647 result = un;
4648 } else {
4649 break;
4650 }
4651 } else if (result->is_ClearArray()) {
4652 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) {
4653 // Can not bypass initialization of the instance
4654 // we are looking for.
4655 break;
4656 }
4657 // Otherwise skip it (the call updated 'result' value).
4658 } else if (result->Opcode() == Op_SCMemProj) {
4659 Node* mem = result->in(0);
4660 Node* adr = nullptr;
4661 if (mem->is_LoadStore()) {
4662 adr = mem->in(MemNode::Address);
4663 } else {
4664 assert(mem->Opcode() == Op_EncodeISOArray ||
4665 mem->Opcode() == Op_StrCompressedCopy, "sanity");
4666 adr = mem->in(3); // Memory edge corresponds to destination array
4667 }
4668 const Type *at = igvn->type(adr);
4669 if (at != Type::TOP) {
4670 assert(at->isa_ptr() != nullptr, "pointer type required.");
4671 int idx = C->get_alias_index(at->is_ptr());
4672 if (idx == alias_idx) {
4673 // Assert in debug mode
4674 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
4675 break; // In product mode return SCMemProj node
4676 }
4677 }
4678 result = mem->in(MemNode::Memory);
4679 } else if (result->Opcode() == Op_StrInflatedCopy) {
4680 Node* adr = result->in(3); // Memory edge corresponds to destination array
4681 const Type *at = igvn->type(adr);
4682 if (at != Type::TOP) {
4683 assert(at->isa_ptr() != nullptr, "pointer type required.");
4684 int idx = C->get_alias_index(at->is_ptr());
4685 if (idx == alias_idx) {
4686 // Assert in debug mode
4687 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
4688 break; // In product mode return SCMemProj node
4689 }
4690 }
4691 result = result->in(MemNode::Memory);
4692 }
4693 }
4694 if (result->is_Phi()) {
4695 PhiNode *mphi = result->as_Phi();
4696 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
4697 const TypePtr *t = mphi->adr_type();
4698 if (!is_instance) {
4699 // Push all non-instance Phis on the orig_phis worklist to update inputs
4700 // during Phase 4 if needed.
4701 orig_phis.push(mphi);
4702 } else if (C->get_alias_index(t) != alias_idx) {
4703 // Create a new Phi with the specified alias index type.
4704 result = split_memory_phi(mphi, alias_idx, orig_phis, rec_depth + 1);
4705 }
4706 }
4707 // the result is either MemNode, PhiNode, InitializeNode.
4708 return result;
4709 }
4710
4711 //
4712 // Convert the types of non-escaped object to instance types where possible,
4713 // propagate the new type information through the graph, and update memory
4714 // edges and MergeMem inputs to reflect the new type.
4715 //
4716 // We start with allocations (and calls which may be allocations) on alloc_worklist.
4717 // The processing is done in 4 phases:
4718 //
4719 // Phase 1: Process possible allocations from alloc_worklist. Create instance
4720 // types for the CheckCastPP for allocations where possible.
4721 // Propagate the new types through users as follows:
4722 // casts and Phi: push users on alloc_worklist
4723 // AddP: cast Base and Address inputs to the instance type
4724 // push any AddP users on alloc_worklist and push any memnode
4725 // users onto memnode_worklist.
4726 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
4727 // search the Memory chain for a store with the appropriate type
4728 // address type. If a Phi is found, create a new version with
4729 // the appropriate memory slices from each of the Phi inputs.
4730 // For stores, process the users as follows:
4731 // MemNode: push on memnode_worklist
4732 // MergeMem: push on mergemem_worklist
4733 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
4734 // moving the first node encountered of each instance type to the
4735 // the input corresponding to its alias index.
4736 // appropriate memory slice.
4737 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
4738 //
4739 // In the following example, the CheckCastPP nodes are the cast of allocation
4740 // results and the allocation of node 29 is non-escaped and eligible to be an
4741 // instance type.
4742 //
4743 // We start with:
4744 //
4745 // 7 Parm #memory
4746 // 10 ConI "12"
4747 // 19 CheckCastPP "Foo"
4748 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
4749 // 29 CheckCastPP "Foo"
4750 // 30 AddP _ 29 29 10 Foo+12 alias_index=4
4751 //
4752 // 40 StoreP 25 7 20 ... alias_index=4
4753 // 50 StoreP 35 40 30 ... alias_index=4
4754 // 60 StoreP 45 50 20 ... alias_index=4
4755 // 70 LoadP _ 60 30 ... alias_index=4
4756 // 80 Phi 75 50 60 Memory alias_index=4
4757 // 90 LoadP _ 80 30 ... alias_index=4
4758 // 100 LoadP _ 80 20 ... alias_index=4
4759 //
4760 //
4761 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
4762 // and creating a new alias index for node 30. This gives:
4763 //
4764 // 7 Parm #memory
4765 // 10 ConI "12"
4766 // 19 CheckCastPP "Foo"
4767 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
4768 // 29 CheckCastPP "Foo" iid=24
4769 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
4770 //
4771 // 40 StoreP 25 7 20 ... alias_index=4
4772 // 50 StoreP 35 40 30 ... alias_index=6
4773 // 60 StoreP 45 50 20 ... alias_index=4
4774 // 70 LoadP _ 60 30 ... alias_index=6
4775 // 80 Phi 75 50 60 Memory alias_index=4
4776 // 90 LoadP _ 80 30 ... alias_index=6
4777 // 100 LoadP _ 80 20 ... alias_index=4
4778 //
4779 // In phase 2, new memory inputs are computed for the loads and stores,
4780 // And a new version of the phi is created. In phase 4, the inputs to
4781 // node 80 are updated and then the memory nodes are updated with the
4782 // values computed in phase 2. This results in:
4783 //
4784 // 7 Parm #memory
4785 // 10 ConI "12"
4786 // 19 CheckCastPP "Foo"
4787 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
4788 // 29 CheckCastPP "Foo" iid=24
4789 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
4790 //
4791 // 40 StoreP 25 7 20 ... alias_index=4
4792 // 50 StoreP 35 7 30 ... alias_index=6
4793 // 60 StoreP 45 40 20 ... alias_index=4
4794 // 70 LoadP _ 50 30 ... alias_index=6
4795 // 80 Phi 75 40 60 Memory alias_index=4
4796 // 120 Phi 75 50 50 Memory alias_index=6
4797 // 90 LoadP _ 120 30 ... alias_index=6
4798 // 100 LoadP _ 80 20 ... alias_index=4
4799 //
4800 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist,
4801 GrowableArray<ArrayCopyNode*> &arraycopy_worklist,
4802 GrowableArray<MergeMemNode*> &mergemem_worklist,
4803 Unique_Node_List &reducible_merges) {
4804 DEBUG_ONLY(Unique_Node_List reduced_merges;)
4805 Unique_Node_List memnode_worklist;
4806 Unique_Node_List orig_phis;
4807 PhaseIterGVN *igvn = _igvn;
4808 uint new_index_start = (uint) _compile->num_alias_types();
4809 VectorSet visited;
4810 ideal_nodes.clear(); // Reset for use with set_map/get_map.
4811
4812 // Phase 1: Process possible allocations from alloc_worklist.
4813 // Create instance types for the CheckCastPP for allocations where possible.
4814 //
4815 // (Note: don't forget to change the order of the second AddP node on
4816 // the alloc_worklist if the order of the worklist processing is changed,
4817 // see the comment in find_second_addp().)
4818 //
4819 while (alloc_worklist.length() != 0) {
4820 Node *n = alloc_worklist.pop();
4821 uint ni = n->_idx;
4822 if (n->is_Call()) {
4823 CallNode *alloc = n->as_Call();
4824 // copy escape information to call node
4825 PointsToNode* ptn = ptnode_adr(alloc->_idx);
4826 PointsToNode::EscapeState es = ptn->escape_state();
4827 // We have an allocation or call which returns a Java object,
4828 // see if it is non-escaped.
4829 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable()) {
4830 continue;
4831 }
4832 // Find CheckCastPP for the allocate or for the return value of a call
4833 n = alloc->result_cast();
4834 if (n == nullptr) { // No uses except Initialize node
4835 if (alloc->is_Allocate()) {
4836 // Set the scalar_replaceable flag for allocation
4837 // so it could be eliminated if it has no uses.
4838 alloc->as_Allocate()->_is_scalar_replaceable = true;
4839 }
4840 continue;
4841 }
4842 if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
4843 // we could reach here for allocate case if one init is associated with many allocs.
4844 if (alloc->is_Allocate()) {
4845 alloc->as_Allocate()->_is_scalar_replaceable = false;
4846 }
4847 continue;
4848 }
4849
4850 // The inline code for Object.clone() casts the allocation result to
4851 // java.lang.Object and then to the actual type of the allocated
4852 // object. Detect this case and use the second cast.
4853 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
4854 // the allocation result is cast to java.lang.Object and then
4855 // to the actual Array type.
4856 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
4857 && (alloc->is_AllocateArray() ||
4858 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeInstKlassPtr::OBJECT)) {
4859 Node *cast2 = nullptr;
4860 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
4861 Node *use = n->fast_out(i);
4862 if (use->is_CheckCastPP()) {
4863 cast2 = use;
4864 break;
4865 }
4866 }
4867 if (cast2 != nullptr) {
4868 n = cast2;
4869 } else {
4870 // Non-scalar replaceable if the allocation type is unknown statically
4871 // (reflection allocation), the object can't be restored during
4872 // deoptimization without precise type.
4873 continue;
4874 }
4875 }
4876
4877 const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
4878 if (t == nullptr) {
4879 continue; // not a TypeOopPtr
4880 }
4881 if (!t->klass_is_exact()) {
4882 continue; // not an unique type
4883 }
4884 if (alloc->is_Allocate()) {
4885 // Set the scalar_replaceable flag for allocation
4886 // so it could be eliminated.
4887 alloc->as_Allocate()->_is_scalar_replaceable = true;
4888 }
4889 set_escape_state(ptnode_adr(n->_idx), es NOT_PRODUCT(COMMA trace_propagate_message(ptn))); // CheckCastPP escape state
4890 // in order for an object to be scalar-replaceable, it must be:
4891 // - a direct allocation (not a call returning an object)
4892 // - non-escaping
4893 // - eligible to be a unique type
4894 // - not determined to be ineligible by escape analysis
4895 set_map(alloc, n);
4896 set_map(n, alloc);
4897 const TypeOopPtr* tinst = t->cast_to_instance_id(ni);
4898 igvn->hash_delete(n);
4899 igvn->set_type(n, tinst);
4900 n->raise_bottom_type(tinst);
4901 igvn->hash_insert(n);
4902 record_for_optimizer(n);
4903 // Allocate an alias index for the header fields. Accesses to
4904 // the header emitted during macro expansion wouldn't have
4905 // correct memory state otherwise.
4906 _compile->get_alias_index(tinst->add_offset(oopDesc::mark_offset_in_bytes()));
4907 _compile->get_alias_index(tinst->add_offset(oopDesc::klass_offset_in_bytes()));
4908 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) {
4909 // Add a new NarrowMem projection for each existing NarrowMem projection with new adr type
4910 InitializeNode* init = alloc->as_Allocate()->initialization();
4911 assert(init != nullptr, "can't find Initialization node for this Allocate node");
4912 auto process_narrow_proj = [&](NarrowMemProjNode* proj) {
4913 const TypePtr* adr_type = proj->adr_type();
4914 const TypePtr* new_adr_type = tinst->with_offset(adr_type->offset());
4915 if (adr_type->isa_aryptr()) {
4916 // In the case of a flat inline type array, each field has its own slice so we need a
4917 // NarrowMemProj for each field of the flat array elements
4918 new_adr_type = new_adr_type->is_aryptr()->with_field_offset(adr_type->is_aryptr()->field_offset().get());
4919 }
4920 if (adr_type != new_adr_type && !init->already_has_narrow_mem_proj_with_adr_type(new_adr_type)) {
4921 // Do NOT remove the next line: ensure a new alias index is allocated for the instance type.
4922 uint alias_idx = _compile->get_alias_index(new_adr_type);
4923 assert(_compile->get_general_index(alias_idx) == _compile->get_alias_index(adr_type), "new adr type should be narrowed down from existing adr type");
4924 NarrowMemProjNode* new_proj = new NarrowMemProjNode(init, new_adr_type);
4925 igvn->set_type(new_proj, new_proj->bottom_type());
4926 record_for_optimizer(new_proj);
4927 set_map(proj, new_proj); // record it so ConnectionGraph::find_inst_mem() can find it
4928 }
4929 };
4930 init->for_each_narrow_mem_proj_with_new_uses(process_narrow_proj);
4931
4932 // First, put on the worklist all Field edges from Connection Graph
4933 // which is more accurate than putting immediate users from Ideal Graph.
4934 for (EdgeIterator e(ptn); e.has_next(); e.next()) {
4935 PointsToNode* tgt = e.get();
4936 if (tgt->is_Arraycopy()) {
4937 continue;
4938 }
4939 Node* use = tgt->ideal_node();
4940 assert(tgt->is_Field() && use->is_AddP(),
4941 "only AddP nodes are Field edges in CG");
4942 if (use->outcnt() > 0) { // Don't process dead nodes
4943 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
4944 if (addp2 != nullptr) {
4945 assert(alloc->is_AllocateArray(),"array allocation was expected");
4946 alloc_worklist.append_if_missing(addp2);
4947 }
4948 alloc_worklist.append_if_missing(use);
4949 }
4950 }
4951
4952 // An allocation may have an Initialize which has raw stores. Scan
4953 // the users of the raw allocation result and push AddP users
4954 // on alloc_worklist.
4955 Node *raw_result = alloc->proj_out_or_null(TypeFunc::Parms);
4956 assert (raw_result != nullptr, "must have an allocation result");
4957 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
4958 Node *use = raw_result->fast_out(i);
4959 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
4960 Node* addp2 = find_second_addp(use, raw_result);
4961 if (addp2 != nullptr) {
4962 assert(alloc->is_AllocateArray(),"array allocation was expected");
4963 alloc_worklist.append_if_missing(addp2);
4964 }
4965 alloc_worklist.append_if_missing(use);
4966 } else if (use->is_MemBar()) {
4967 memnode_worklist.push(use);
4968 }
4969 }
4970 }
4971 } else if (n->is_AddP()) {
4972 if (has_reducible_merge_base(n->as_AddP(), reducible_merges)) {
4973 // This AddP will go away when we reduce the Phi
4974 continue;
4975 }
4976 Node* addp_base = get_addp_base(n);
4977 JavaObjectNode* jobj = unique_java_object(addp_base);
4978 if (jobj == nullptr || jobj == phantom_obj) {
4979 #ifdef ASSERT
4980 ptnode_adr(get_addp_base(n)->_idx)->dump();
4981 ptnode_adr(n->_idx)->dump();
4982 assert(jobj != nullptr && jobj != phantom_obj, "escaped allocation");
4983 #endif
4984 _compile->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
4985 return;
4986 }
4987 Node *base = get_map(jobj->idx()); // CheckCastPP node
4988 if (!split_AddP(n, base)) continue; // wrong type from dead path
4989 } else if (n->is_Phi() ||
4990 n->is_CheckCastPP() ||
4991 n->is_EncodeP() ||
4992 n->is_DecodeN() ||
4993 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
4994 if (visited.test_set(n->_idx)) {
4995 assert(n->is_Phi(), "loops only through Phi's");
4996 continue; // already processed
4997 }
4998 // Reducible Phi's will be removed from the graph after split_unique_types
4999 // finishes. For now we just try to split out the SR inputs of the merge.
5000 Node* parent = n->in(1);
5001 if (reducible_merges.member(n)) {
5002 reduce_phi(n->as_Phi(), alloc_worklist);
5003 #ifdef ASSERT
5004 if (VerifyReduceAllocationMerges) {
5005 reduced_merges.push(n);
5006 }
5007 #endif
5008 continue;
5009 } else if (reducible_merges.member(parent)) {
5010 // 'n' is an user of a reducible merge (a Phi). It will be simplified as
5011 // part of reduce_merge.
5012 continue;
5013 }
5014 JavaObjectNode* jobj = unique_java_object(n);
5015 if (jobj == nullptr || jobj == phantom_obj) {
5016 #ifdef ASSERT
5017 ptnode_adr(n->_idx)->dump();
5018 assert(jobj != nullptr && jobj != phantom_obj, "escaped allocation");
5019 #endif
5020 _compile->record_failure(_invocation > 0 ? C2Compiler::retry_no_iterative_escape_analysis() : C2Compiler::retry_no_escape_analysis());
5021 return;
5022 } else {
5023 Node *val = get_map(jobj->idx()); // CheckCastPP node
5024 TypeNode *tn = n->as_Type();
5025 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr();
5026 assert(tinst != nullptr && tinst->is_known_instance() &&
5027 tinst->instance_id() == jobj->idx() , "instance type expected.");
5028
5029 const Type *tn_type = igvn->type(tn);
5030 const TypeOopPtr *tn_t;
5031 if (tn_type->isa_narrowoop()) {
5032 tn_t = tn_type->make_ptr()->isa_oopptr();
5033 } else {
5034 tn_t = tn_type->isa_oopptr();
5035 }
5036 if (tn_t != nullptr && tinst->maybe_java_subtype_of(tn_t)) {
5037 if (tn_t->isa_aryptr()) {
5038 // Keep array properties (not flat/null-free)
5039 tinst = tinst->is_aryptr()->update_properties(tn_t->is_aryptr());
5040 if (tinst == nullptr) {
5041 continue; // Skip dead path with inconsistent properties
5042 }
5043 }
5044 if (tn_type->isa_narrowoop()) {
5045 tn_type = tinst->make_narrowoop();
5046 } else {
5047 tn_type = tinst;
5048 }
5049 igvn->hash_delete(tn);
5050 igvn->set_type(tn, tn_type);
5051 tn->set_type(tn_type);
5052 igvn->hash_insert(tn);
5053 record_for_optimizer(n);
5054 } else {
5055 assert(tn_type == TypePtr::NULL_PTR ||
5056 (tn_t != nullptr && !tinst->maybe_java_subtype_of(tn_t)),
5057 "unexpected type");
5058 continue; // Skip dead path with different type
5059 }
5060 }
5061 } else {
5062 DEBUG_ONLY(n->dump();)
5063 assert(false, "EA: unexpected node");
5064 continue;
5065 }
5066 // push allocation's users on appropriate worklist
5067 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
5068 Node *use = n->fast_out(i);
5069 if (use->is_Mem() && use->in(MemNode::Address) == n) {
5070 // Load/store to instance's field
5071 memnode_worklist.push(use);
5072 } else if (use->is_MemBar()) {
5073 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
5074 memnode_worklist.push(use);
5075 }
5076 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
5077 Node* addp2 = find_second_addp(use, n);
5078 if (addp2 != nullptr) {
5079 alloc_worklist.append_if_missing(addp2);
5080 }
5081 alloc_worklist.append_if_missing(use);
5082 } else if (use->is_Phi() ||
5083 use->is_CheckCastPP() ||
5084 use->is_EncodeNarrowPtr() ||
5085 use->is_DecodeNarrowPtr() ||
5086 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
5087 alloc_worklist.append_if_missing(use);
5088 #ifdef ASSERT
5089 } else if (use->is_Mem()) {
5090 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
5091 } else if (use->is_MergeMem()) {
5092 assert(mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
5093 } else if (use->is_SafePoint()) {
5094 // Look for MergeMem nodes for calls which reference unique allocation
5095 // (through CheckCastPP nodes) even for debug info.
5096 Node* m = use->in(TypeFunc::Memory);
5097 if (m->is_MergeMem()) {
5098 assert(mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
5099 }
5100 } else if (use->Opcode() == Op_EncodeISOArray) {
5101 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
5102 // EncodeISOArray overwrites destination array
5103 memnode_worklist.push(use);
5104 }
5105 } else if (use->Opcode() == Op_Return) {
5106 // Allocation is referenced by field of returned inline type
5107 assert(_compile->tf()->returns_inline_type_as_fields(), "EA: unexpected reference by ReturnNode");
5108 } else {
5109 uint op = use->Opcode();
5110 if ((op == Op_StrCompressedCopy || op == Op_StrInflatedCopy) &&
5111 (use->in(MemNode::Memory) == n)) {
5112 // They overwrite memory edge corresponding to destination array,
5113 memnode_worklist.push(use);
5114 } else if (!(op == Op_CmpP || op == Op_Conv2B ||
5115 op == Op_CastP2X ||
5116 op == Op_FastLock || op == Op_AryEq ||
5117 op == Op_StrComp || op == Op_CountPositives ||
5118 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
5119 op == Op_StrEquals || op == Op_VectorizedHashCode ||
5120 op == Op_StrIndexOf || op == Op_StrIndexOfChar ||
5121 op == Op_SubTypeCheck || op == Op_InlineType || op == Op_FlatArrayCheck ||
5122 op == Op_ReinterpretS2HF ||
5123 op == Op_ReachabilityFence ||
5124 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use))) {
5125 n->dump();
5126 use->dump();
5127 assert(false, "EA: missing allocation reference path");
5128 }
5129 #endif
5130 }
5131 }
5132
5133 }
5134
5135 #ifdef ASSERT
5136 if (VerifyReduceAllocationMerges) {
5137 for (uint i = 0; i < reducible_merges.size(); i++) {
5138 Node* phi = reducible_merges.at(i);
5139
5140 if (!reduced_merges.member(phi)) {
5141 phi->dump(2);
5142 phi->dump(-2);
5143 assert(false, "This reducible merge wasn't reduced.");
5144 }
5145
5146 // At this point reducible Phis shouldn't have AddP users anymore; only SafePoints or Casts.
5147 for (DUIterator_Fast jmax, j = phi->fast_outs(jmax); j < jmax; j++) {
5148 Node* use = phi->fast_out(j);
5149 if (!use->is_SafePoint() && !use->is_CastPP()) {
5150 phi->dump(2);
5151 phi->dump(-2);
5152 assert(false, "Unexpected user of reducible Phi -> %d:%s:%d", use->_idx, use->Name(), use->outcnt());
5153 }
5154 }
5155 }
5156 }
5157 #endif
5158
5159 // Go over all ArrayCopy nodes and if one of the inputs has a unique
5160 // type, record it in the ArrayCopy node so we know what memory this
5161 // node uses/modified.
5162 for (int next = 0; next < arraycopy_worklist.length(); next++) {
5163 ArrayCopyNode* ac = arraycopy_worklist.at(next);
5164 Node* dest = ac->in(ArrayCopyNode::Dest);
5165 if (dest->is_AddP()) {
5166 dest = get_addp_base(dest);
5167 }
5168 JavaObjectNode* jobj = unique_java_object(dest);
5169 if (jobj != nullptr) {
5170 Node *base = get_map(jobj->idx());
5171 if (base != nullptr) {
5172 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
5173 ac->_dest_type = base_t;
5174 }
5175 }
5176 Node* src = ac->in(ArrayCopyNode::Src);
5177 if (src->is_AddP()) {
5178 src = get_addp_base(src);
5179 }
5180 jobj = unique_java_object(src);
5181 if (jobj != nullptr) {
5182 Node* base = get_map(jobj->idx());
5183 if (base != nullptr) {
5184 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
5185 ac->_src_type = base_t;
5186 }
5187 }
5188 }
5189
5190 // New alias types were created in split_AddP().
5191 uint new_index_end = (uint) _compile->num_alias_types();
5192
5193 _compile->print_method(PHASE_EA_AFTER_SPLIT_UNIQUE_TYPES_1, 5);
5194
5195 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
5196 // compute new values for Memory inputs (the Memory inputs are not
5197 // actually updated until phase 4.)
5198 if (memnode_worklist.size() == 0) {
5199 return; // nothing to do
5200 }
5201 while (memnode_worklist.size() != 0) {
5202 Node *n = memnode_worklist.pop();
5203 if (visited.test_set(n->_idx)) {
5204 continue;
5205 }
5206 if (n->is_Phi()) {
5207 if ((uint) _compile->get_alias_index(n->adr_type()) < new_index_start) {
5208 // Push memory phis on the orig_phis worklist to update
5209 // during Phase 4 if needed.
5210 orig_phis.push(n);
5211 }
5212 } else if (n->is_ClearArray()) {
5213 // we don't need to do anything, but the users must be pushed
5214 } else if (n->is_MemBar()) { // MemBar nodes
5215 if (!n->is_Initialize()) { // memory projections for Initialize pushed below (so we get to all their uses)
5216 // we don't need to do anything, but the users must be pushed
5217 n = n->as_MemBar()->proj_out_or_null(TypeFunc::Memory);
5218 if (n == nullptr) {
5219 continue;
5220 }
5221 }
5222 } else if (n->is_CallLeaf()) {
5223 // Runtime calls with narrow memory input (no MergeMem node)
5224 // get the memory projection
5225 n = n->as_Call()->proj_out_or_null(TypeFunc::Memory);
5226 if (n == nullptr) {
5227 continue;
5228 }
5229 } else if (n->Opcode() == Op_StrInflatedCopy) {
5230 // Check direct uses of StrInflatedCopy.
5231 // It is memory type Node - no special SCMemProj node.
5232 } else if (n->Opcode() == Op_StrCompressedCopy ||
5233 n->Opcode() == Op_EncodeISOArray) {
5234 // get the memory projection
5235 n = n->find_out_with(Op_SCMemProj);
5236 assert(n != nullptr && n->Opcode() == Op_SCMemProj, "memory projection required");
5237 } else if (n->is_CallLeaf() && n->as_CallLeaf()->_name != nullptr &&
5238 strcmp(n->as_CallLeaf()->_name, "store_unknown_inline") == 0) {
5239 n = n->as_CallLeaf()->proj_out(TypeFunc::Memory);
5240 } else if (n->is_Proj()) {
5241 assert(n->in(0)->is_Initialize(), "we only push memory projections for Initialize");
5242 } else {
5243 #ifdef ASSERT
5244 if (!n->is_Mem()) {
5245 n->dump();
5246 }
5247 assert(n->is_Mem(), "memory node required.");
5248 #endif
5249 Node *addr = n->in(MemNode::Address);
5250 const Type *addr_t = igvn->type(addr);
5251 if (addr_t == Type::TOP) {
5252 continue;
5253 }
5254 assert (addr_t->isa_ptr() != nullptr, "pointer type required.");
5255 int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
5256 assert ((uint)alias_idx < new_index_end, "wrong alias index");
5257 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis);
5258 if (_compile->failing()) {
5259 return;
5260 }
5261 if (mem != n->in(MemNode::Memory)) {
5262 // We delay the memory edge update since we need old one in
5263 // MergeMem code below when instances memory slices are separated.
5264 set_map(n, mem);
5265 }
5266 if (n->is_Load()) {
5267 continue; // don't push users
5268 } else if (n->is_LoadStore()) {
5269 // get the memory projection
5270 n = n->find_out_with(Op_SCMemProj);
5271 assert(n != nullptr && n->Opcode() == Op_SCMemProj, "memory projection required");
5272 }
5273 }
5274 // push user on appropriate worklist
5275 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
5276 Node *use = n->fast_out(i);
5277 if (use->is_Phi() || use->is_ClearArray()) {
5278 memnode_worklist.push(use);
5279 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) {
5280 memnode_worklist.push(use);
5281 } else if (use->is_MemBar() || use->is_CallLeaf()) {
5282 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
5283 memnode_worklist.push(use);
5284 }
5285 } else if (use->is_Proj()) {
5286 assert(n->is_Initialize(), "We only push projections of Initialize");
5287 if (use->as_Proj()->_con == TypeFunc::Memory) { // Ignore precedent edge
5288 memnode_worklist.push(use);
5289 }
5290 #ifdef ASSERT
5291 } else if (use->is_Mem()) {
5292 assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
5293 } else if (use->is_MergeMem()) {
5294 assert(mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
5295 } else if (use->Opcode() == Op_EncodeISOArray) {
5296 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
5297 // EncodeISOArray overwrites destination array
5298 memnode_worklist.push(use);
5299 }
5300 } else if (use->is_CallLeaf() && use->as_CallLeaf()->_name != nullptr &&
5301 strcmp(use->as_CallLeaf()->_name, "store_unknown_inline") == 0) {
5302 // store_unknown_inline overwrites destination array
5303 memnode_worklist.push(use);
5304 } else {
5305 uint op = use->Opcode();
5306 if ((use->in(MemNode::Memory) == n) &&
5307 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) {
5308 // They overwrite memory edge corresponding to destination array,
5309 memnode_worklist.push(use);
5310 } else if (!(BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use) ||
5311 op == Op_AryEq || op == Op_StrComp || op == Op_CountPositives ||
5312 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy || op == Op_VectorizedHashCode ||
5313 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar || op == Op_FlatArrayCheck)) {
5314 n->dump();
5315 use->dump();
5316 assert(false, "EA: missing memory path");
5317 }
5318 #endif
5319 }
5320 }
5321 }
5322
5323 // Phase 3: Process MergeMem nodes from mergemem_worklist.
5324 // Walk each memory slice moving the first node encountered of each
5325 // instance type to the input corresponding to its alias index.
5326 uint length = mergemem_worklist.length();
5327 for( uint next = 0; next < length; ++next ) {
5328 MergeMemNode* nmm = mergemem_worklist.at(next);
5329 assert(!visited.test_set(nmm->_idx), "should not be visited before");
5330 // Note: we don't want to use MergeMemStream here because we only want to
5331 // scan inputs which exist at the start, not ones we add during processing.
5332 // Note 2: MergeMem may already contains instance memory slices added
5333 // during find_inst_mem() call when memory nodes were processed above.
5334 igvn->hash_delete(nmm);
5335 uint nslices = MIN2(nmm->req(), new_index_start);
5336 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
5337 Node* mem = nmm->in(i);
5338 Node* cur = nullptr;
5339 if (mem == nullptr || mem->is_top()) {
5340 continue;
5341 }
5342 // First, update mergemem by moving memory nodes to corresponding slices
5343 // if their type became more precise since this mergemem was created.
5344 while (mem->is_Mem()) {
5345 const Type* at = igvn->type(mem->in(MemNode::Address));
5346 if (at != Type::TOP) {
5347 assert (at->isa_ptr() != nullptr, "pointer type required.");
5348 uint idx = (uint)_compile->get_alias_index(at->is_ptr());
5349 if (idx == i) {
5350 if (cur == nullptr) {
5351 cur = mem;
5352 }
5353 } else {
5354 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
5355 nmm->set_memory_at(idx, mem);
5356 }
5357 }
5358 }
5359 mem = mem->in(MemNode::Memory);
5360 }
5361 nmm->set_memory_at(i, (cur != nullptr) ? cur : mem);
5362 // Find any instance of the current type if we haven't encountered
5363 // already a memory slice of the instance along the memory chain.
5364 for (uint ni = new_index_start; ni < new_index_end; ni++) {
5365 if((uint)_compile->get_general_index(ni) == i) {
5366 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
5367 if (nmm->is_empty_memory(m)) {
5368 Node* result = find_inst_mem(mem, ni, orig_phis);
5369 if (_compile->failing()) {
5370 return;
5371 }
5372 nmm->set_memory_at(ni, result);
5373 }
5374 }
5375 }
5376 }
5377 // Find the rest of instances values
5378 for (uint ni = new_index_start; ni < new_index_end; ni++) {
5379 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
5380 Node* result = step_through_mergemem(nmm, ni, tinst);
5381 if (result == nmm->base_memory()) {
5382 // Didn't find instance memory, search through general slice recursively.
5383 result = nmm->memory_at(_compile->get_general_index(ni));
5384 result = find_inst_mem(result, ni, orig_phis);
5385 if (_compile->failing()) {
5386 return;
5387 }
5388 nmm->set_memory_at(ni, result);
5389 }
5390 }
5391
5392 // If we have crossed the 3/4 point of max node limit it's too risky
5393 // to continue with EA/SR because we might hit the max node limit.
5394 if (_compile->live_nodes() >= _compile->max_node_limit() * 0.75) {
5395 if (_compile->do_reduce_allocation_merges()) {
5396 _compile->record_failure(C2Compiler::retry_no_reduce_allocation_merges());
5397 } else if (_invocation > 0) {
5398 _compile->record_failure(C2Compiler::retry_no_iterative_escape_analysis());
5399 } else {
5400 _compile->record_failure(C2Compiler::retry_no_escape_analysis());
5401 }
5402 return;
5403 }
5404
5405 igvn->hash_insert(nmm);
5406 record_for_optimizer(nmm);
5407 }
5408
5409 _compile->print_method(PHASE_EA_AFTER_SPLIT_UNIQUE_TYPES_3, 5);
5410
5411 // Phase 4: Update the inputs of non-instance memory Phis and
5412 // the Memory input of memnodes
5413 // First update the inputs of any non-instance Phi's from
5414 // which we split out an instance Phi. Note we don't have
5415 // to recursively process Phi's encountered on the input memory
5416 // chains as is done in split_memory_phi() since they will
5417 // also be processed here.
5418 for (uint j = 0; j < orig_phis.size(); j++) {
5419 PhiNode* phi = orig_phis.at(j)->as_Phi();
5420 int alias_idx = _compile->get_alias_index(phi->adr_type());
5421 igvn->hash_delete(phi);
5422 for (uint i = 1; i < phi->req(); i++) {
5423 Node *mem = phi->in(i);
5424 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis);
5425 if (_compile->failing()) {
5426 return;
5427 }
5428 if (mem != new_mem) {
5429 phi->set_req(i, new_mem);
5430 }
5431 }
5432 igvn->hash_insert(phi);
5433 record_for_optimizer(phi);
5434 }
5435
5436 // Update the memory inputs of MemNodes with the value we computed
5437 // in Phase 2 and move stores memory users to corresponding memory slices.
5438 // Disable memory split verification code until the fix for 6984348.
5439 // Currently it produces false negative results since it does not cover all cases.
5440 #if 0 // ifdef ASSERT
5441 visited.Reset();
5442 Node_Stack old_mems(arena, _compile->unique() >> 2);
5443 #endif
5444 for (uint i = 0; i < ideal_nodes.size(); i++) {
5445 Node* n = ideal_nodes.at(i);
5446 Node* nmem = get_map(n->_idx);
5447 assert(nmem != nullptr, "sanity");
5448 if (n->is_Mem()) {
5449 #if 0 // ifdef ASSERT
5450 Node* old_mem = n->in(MemNode::Memory);
5451 if (!visited.test_set(old_mem->_idx)) {
5452 old_mems.push(old_mem, old_mem->outcnt());
5453 }
5454 #endif
5455 assert(n->in(MemNode::Memory) != nmem, "sanity");
5456 if (!n->is_Load()) {
5457 // Move memory users of a store first.
5458 move_inst_mem(n, orig_phis);
5459 }
5460 // Now update memory input
5461 igvn->hash_delete(n);
5462 n->set_req(MemNode::Memory, nmem);
5463 igvn->hash_insert(n);
5464 record_for_optimizer(n);
5465 } else {
5466 assert(n->is_Allocate() || n->is_CheckCastPP() ||
5467 n->is_AddP() || n->is_Phi() || n->is_NarrowMemProj(), "unknown node used for set_map()");
5468 }
5469 }
5470 #if 0 // ifdef ASSERT
5471 // Verify that memory was split correctly
5472 while (old_mems.is_nonempty()) {
5473 Node* old_mem = old_mems.node();
5474 uint old_cnt = old_mems.index();
5475 old_mems.pop();
5476 assert(old_cnt == old_mem->outcnt(), "old mem could be lost");
5477 }
5478 #endif
5479 _compile->print_method(PHASE_EA_AFTER_SPLIT_UNIQUE_TYPES_4, 5);
5480 }
5481
5482 #ifndef PRODUCT
5483 int ConnectionGraph::_no_escape_counter = 0;
5484 int ConnectionGraph::_arg_escape_counter = 0;
5485 int ConnectionGraph::_global_escape_counter = 0;
5486
5487 static const char *node_type_names[] = {
5488 "UnknownType",
5489 "JavaObject",
5490 "LocalVar",
5491 "Field",
5492 "Arraycopy"
5493 };
5494
5495 static const char *esc_names[] = {
5496 "UnknownEscape",
5497 "NoEscape",
5498 "ArgEscape",
5499 "GlobalEscape"
5500 };
5501
5502 const char* PointsToNode::esc_name() const {
5503 return esc_names[(int)escape_state()];
5504 }
5505
5506 void PointsToNode::dump_header(bool print_state, outputStream* out) const {
5507 NodeType nt = node_type();
5508 out->print("%s(%d) ", node_type_names[(int) nt], _pidx);
5509 if (print_state) {
5510 EscapeState es = escape_state();
5511 EscapeState fields_es = fields_escape_state();
5512 out->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]);
5513 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable()) {
5514 out->print("NSR ");
5515 }
5516 }
5517 }
5518
5519 void PointsToNode::dump(bool print_state, outputStream* out, bool newline) const {
5520 dump_header(print_state, out);
5521 if (is_Field()) {
5522 FieldNode* f = (FieldNode*)this;
5523 if (f->is_oop()) {
5524 out->print("oop ");
5525 }
5526 if (f->offset() > 0) {
5527 out->print("+%d ", f->offset());
5528 }
5529 out->print("(");
5530 for (BaseIterator i(f); i.has_next(); i.next()) {
5531 PointsToNode* b = i.get();
5532 out->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : ""));
5533 }
5534 out->print(" )");
5535 }
5536 out->print("[");
5537 for (EdgeIterator i(this); i.has_next(); i.next()) {
5538 PointsToNode* e = i.get();
5539 out->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : "");
5540 }
5541 out->print(" [");
5542 for (UseIterator i(this); i.has_next(); i.next()) {
5543 PointsToNode* u = i.get();
5544 bool is_base = false;
5545 if (PointsToNode::is_base_use(u)) {
5546 is_base = true;
5547 u = PointsToNode::get_use_node(u)->as_Field();
5548 }
5549 out->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : "");
5550 }
5551 out->print(" ]] ");
5552 if (_node == nullptr) {
5553 out->print("<null>%s", newline ? "\n" : "");
5554 } else {
5555 _node->dump(newline ? "\n" : "", false, out);
5556 }
5557 }
5558
5559 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) {
5560 bool first = true;
5561 int ptnodes_length = ptnodes_worklist.length();
5562 for (int i = 0; i < ptnodes_length; i++) {
5563 PointsToNode *ptn = ptnodes_worklist.at(i);
5564 if (ptn == nullptr || !ptn->is_JavaObject()) {
5565 continue;
5566 }
5567 PointsToNode::EscapeState es = ptn->escape_state();
5568 if ((es != PointsToNode::NoEscape) && !Verbose) {
5569 continue;
5570 }
5571 Node* n = ptn->ideal_node();
5572 if (n->is_Allocate() || (n->is_CallStaticJava() &&
5573 n->as_CallStaticJava()->is_boxing_method())) {
5574 if (first) {
5575 tty->cr();
5576 tty->print("======== Connection graph for ");
5577 _compile->method()->print_short_name();
5578 tty->cr();
5579 tty->print_cr("invocation #%d: %d iterations and %f sec to build connection graph with %d nodes and worklist size %d",
5580 _invocation, _build_iterations, _build_time, nodes_size(), ptnodes_worklist.length());
5581 tty->cr();
5582 first = false;
5583 }
5584 ptn->dump();
5585 // Print all locals and fields which reference this allocation
5586 for (UseIterator j(ptn); j.has_next(); j.next()) {
5587 PointsToNode* use = j.get();
5588 if (use->is_LocalVar()) {
5589 use->dump(Verbose);
5590 } else if (Verbose) {
5591 use->dump();
5592 }
5593 }
5594 tty->cr();
5595 }
5596 }
5597 }
5598
5599 void ConnectionGraph::print_statistics() {
5600 tty->print_cr("No escape = %d, Arg escape = %d, Global escape = %d", AtomicAccess::load(&_no_escape_counter), AtomicAccess::load(&_arg_escape_counter), AtomicAccess::load(&_global_escape_counter));
5601 }
5602
5603 void ConnectionGraph::escape_state_statistics(GrowableArray<JavaObjectNode*>& java_objects_worklist) {
5604 if (!PrintOptoStatistics || (_invocation > 0)) { // Collect data only for the first invocation
5605 return;
5606 }
5607 for (int next = 0; next < java_objects_worklist.length(); ++next) {
5608 JavaObjectNode* ptn = java_objects_worklist.at(next);
5609 if (ptn->ideal_node()->is_Allocate()) {
5610 if (ptn->escape_state() == PointsToNode::NoEscape) {
5611 AtomicAccess::inc(&ConnectionGraph::_no_escape_counter);
5612 } else if (ptn->escape_state() == PointsToNode::ArgEscape) {
5613 AtomicAccess::inc(&ConnectionGraph::_arg_escape_counter);
5614 } else if (ptn->escape_state() == PointsToNode::GlobalEscape) {
5615 AtomicAccess::inc(&ConnectionGraph::_global_escape_counter);
5616 } else {
5617 assert(false, "Unexpected Escape State");
5618 }
5619 }
5620 }
5621 }
5622
5623 void ConnectionGraph::trace_es_update_helper(PointsToNode* ptn, PointsToNode::EscapeState es, bool fields, const char* reason) const {
5624 if (_compile->directive()->TraceEscapeAnalysisOption) {
5625 assert(ptn != nullptr, "should not be null");
5626 assert(reason != nullptr, "should not be null");
5627 ptn->dump_header(true);
5628 PointsToNode::EscapeState new_es = fields ? ptn->escape_state() : es;
5629 PointsToNode::EscapeState new_fields_es = fields ? es : ptn->fields_escape_state();
5630 tty->print_cr("-> %s(%s) %s", esc_names[(int)new_es], esc_names[(int)new_fields_es], reason);
5631 }
5632 }
5633
5634 const char* ConnectionGraph::trace_propagate_message(PointsToNode* from) const {
5635 if (_compile->directive()->TraceEscapeAnalysisOption) {
5636 stringStream ss;
5637 ss.print("propagated from: ");
5638 from->dump(true, &ss, false);
5639 return ss.as_string();
5640 } else {
5641 return nullptr;
5642 }
5643 }
5644
5645 const char* ConnectionGraph::trace_arg_escape_message(CallNode* call) const {
5646 if (_compile->directive()->TraceEscapeAnalysisOption) {
5647 stringStream ss;
5648 ss.print("escapes as arg to:");
5649 call->dump("", false, &ss);
5650 return ss.as_string();
5651 } else {
5652 return nullptr;
5653 }
5654 }
5655
5656 const char* ConnectionGraph::trace_merged_message(PointsToNode* other) const {
5657 if (_compile->directive()->TraceEscapeAnalysisOption) {
5658 stringStream ss;
5659 ss.print("is merged with other object: ");
5660 other->dump_header(true, &ss);
5661 return ss.as_string();
5662 } else {
5663 return nullptr;
5664 }
5665 }
5666
5667 #endif
5668
5669 void ConnectionGraph::record_for_optimizer(Node *n) {
5670 _igvn->_worklist.push(n);
5671 _igvn->add_users_to_worklist(n);
5672 }