1 /*
2 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "ci/bcEscapeAnalyzer.hpp"
27 #include "compiler/compileLog.hpp"
28 #include "gc/shared/c2/barrierSetC2.hpp"
29 #include "libadt/vectset.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/resourceArea.hpp"
32 #include "opto/c2compiler.hpp"
33 #include "opto/arraycopynode.hpp"
34 #include "opto/callnode.hpp"
35 #include "opto/cfgnode.hpp"
36 #include "opto/compile.hpp"
37 #include "opto/escape.hpp"
38 #include "opto/phaseX.hpp"
39 #include "opto/movenode.hpp"
40 #include "opto/rootnode.hpp"
41 #include "utilities/macros.hpp"
42 #if INCLUDE_G1GC
43 #include "gc/g1/g1ThreadLocalData.hpp"
44 #endif // INCLUDE_G1GC
45 #if INCLUDE_ZGC
46 #include "gc/z/c2/zBarrierSetC2.hpp"
47 #endif
48 #if INCLUDE_SHENANDOAHGC
49 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
50 #endif
51
52 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) :
53 _nodes(C->comp_arena(), C->unique(), C->unique(), NULL),
54 _in_worklist(C->comp_arena()),
55 _next_pidx(0),
56 _collecting(true),
57 _verify(false),
58 _compile(C),
59 _igvn(igvn),
60 _node_map(C->comp_arena()) {
61 // Add unknown java object.
62 add_java_object(C->top(), PointsToNode::GlobalEscape);
63 phantom_obj = ptnode_adr(C->top()->_idx)->as_JavaObject();
64 // Add ConP(#NULL) and ConN(#NULL) nodes.
65 Node* oop_null = igvn->zerocon(T_OBJECT);
66 assert(oop_null->_idx < nodes_size(), "should be created already");
67 add_java_object(oop_null, PointsToNode::NoEscape);
68 null_obj = ptnode_adr(oop_null->_idx)->as_JavaObject();
69 if (UseCompressedOops) {
70 Node* noop_null = igvn->zerocon(T_NARROWOOP);
71 assert(noop_null->_idx < nodes_size(), "should be created already");
72 map_ideal_node(noop_null, null_obj);
73 }
74 _pcmp_neq = NULL; // Should be initialized
75 _pcmp_eq = NULL;
76 }
77
78 bool ConnectionGraph::has_candidates(Compile *C) {
79 // EA brings benefits only when the code has allocations and/or locks which
80 // are represented by ideal Macro nodes.
81 int cnt = C->macro_count();
82 for (int i = 0; i < cnt; i++) {
83 Node *n = C->macro_node(i);
84 if (n->is_Allocate())
85 return true;
86 if (n->is_Lock()) {
87 Node* obj = n->as_Lock()->obj_node()->uncast();
88 if (!(obj->is_Parm() || obj->is_Con()))
89 return true;
90 }
91 if (n->is_CallStaticJava() &&
92 n->as_CallStaticJava()->is_boxing_method()) {
93 return true;
94 }
95 }
96 return false;
97 }
98
99 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
100 Compile::TracePhase tp("escapeAnalysis", &Phase::timers[Phase::_t_escapeAnalysis]);
101 ResourceMark rm;
102
103 // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction
104 // to create space for them in ConnectionGraph::_nodes[].
105 Node* oop_null = igvn->zerocon(T_OBJECT);
106 Node* noop_null = igvn->zerocon(T_NARROWOOP);
107 ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn);
108 // Perform escape analysis
109 if (congraph->compute_escape()) {
110 // There are non escaping objects.
111 C->set_congraph(congraph);
112 }
113 // Cleanup.
114 if (oop_null->outcnt() == 0)
115 igvn->hash_delete(oop_null);
116 if (noop_null->outcnt() == 0)
117 igvn->hash_delete(noop_null);
118 }
119
120 bool ConnectionGraph::compute_escape() {
121 Compile* C = _compile;
122 PhaseGVN* igvn = _igvn;
123
124 // Worklists used by EA.
125 Unique_Node_List delayed_worklist;
126 GrowableArray<Node*> alloc_worklist;
127 GrowableArray<Node*> ptr_cmp_worklist;
128 GrowableArray<Node*> storestore_worklist;
129 GrowableArray<ArrayCopyNode*> arraycopy_worklist;
130 GrowableArray<PointsToNode*> ptnodes_worklist;
131 GrowableArray<JavaObjectNode*> java_objects_worklist;
132 GrowableArray<JavaObjectNode*> non_escaped_worklist;
133 GrowableArray<FieldNode*> oop_fields_worklist;
134 DEBUG_ONLY( GrowableArray<Node*> addp_worklist; )
135
136 { Compile::TracePhase tp("connectionGraph", &Phase::timers[Phase::_t_connectionGraph]);
137
138 // 1. Populate Connection Graph (CG) with PointsTo nodes.
139 ideal_nodes.map(C->live_nodes(), NULL); // preallocate space
140 // Initialize worklist
141 if (C->root() != NULL) {
142 ideal_nodes.push(C->root());
143 }
144 // Processed ideal nodes are unique on ideal_nodes list
145 // but several ideal nodes are mapped to the phantom_obj.
146 // To avoid duplicated entries on the following worklists
147 // add the phantom_obj only once to them.
148 ptnodes_worklist.append(phantom_obj);
149 java_objects_worklist.append(phantom_obj);
150 for( uint next = 0; next < ideal_nodes.size(); ++next ) {
151 Node* n = ideal_nodes.at(next);
152 // Create PointsTo nodes and add them to Connection Graph. Called
153 // only once per ideal node since ideal_nodes is Unique_Node list.
154 add_node_to_connection_graph(n, &delayed_worklist);
155 PointsToNode* ptn = ptnode_adr(n->_idx);
156 if (ptn != NULL && ptn != phantom_obj) {
157 ptnodes_worklist.append(ptn);
158 if (ptn->is_JavaObject()) {
159 java_objects_worklist.append(ptn->as_JavaObject());
160 if ((n->is_Allocate() || n->is_CallStaticJava()) &&
161 (ptn->escape_state() < PointsToNode::GlobalEscape)) {
162 // Only allocations and java static calls results are interesting.
163 non_escaped_worklist.append(ptn->as_JavaObject());
164 }
165 } else if (ptn->is_Field() && ptn->as_Field()->is_oop()) {
166 oop_fields_worklist.append(ptn->as_Field());
167 }
168 }
169 if (n->is_MergeMem()) {
170 // Collect all MergeMem nodes to add memory slices for
171 // scalar replaceable objects in split_unique_types().
172 _mergemem_worklist.append(n->as_MergeMem());
173 } else if (OptimizePtrCompare && n->is_Cmp() &&
174 (n->Opcode() == Op_CmpP || n->Opcode() == Op_CmpN)) {
175 // Collect compare pointers nodes.
176 ptr_cmp_worklist.append(n);
177 } else if (n->is_MemBarStoreStore()) {
178 // Collect all MemBarStoreStore nodes so that depending on the
179 // escape status of the associated Allocate node some of them
180 // may be eliminated.
181 storestore_worklist.append(n);
182 } else if (n->is_MemBar() && (n->Opcode() == Op_MemBarRelease) &&
183 (n->req() > MemBarNode::Precedent)) {
184 record_for_optimizer(n);
185 #ifdef ASSERT
186 } else if (n->is_AddP()) {
187 // Collect address nodes for graph verification.
188 addp_worklist.append(n);
189 #endif
190 } else if (n->is_ArrayCopy()) {
191 // Keep a list of ArrayCopy nodes so if one of its input is non
192 // escaping, we can record a unique type
193 arraycopy_worklist.append(n->as_ArrayCopy());
194 }
195 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
196 Node* m = n->fast_out(i); // Get user
197 ideal_nodes.push(m);
198 }
199 }
200 if (non_escaped_worklist.length() == 0) {
201 _collecting = false;
202 return false; // Nothing to do.
203 }
204 // Add final simple edges to graph.
205 while(delayed_worklist.size() > 0) {
206 Node* n = delayed_worklist.pop();
207 add_final_edges(n);
208 }
209 int ptnodes_length = ptnodes_worklist.length();
210
211 #ifdef ASSERT
212 if (VerifyConnectionGraph) {
213 // Verify that no new simple edges could be created and all
214 // local vars has edges.
215 _verify = true;
216 for (int next = 0; next < ptnodes_length; ++next) {
217 PointsToNode* ptn = ptnodes_worklist.at(next);
218 add_final_edges(ptn->ideal_node());
219 if (ptn->is_LocalVar() && ptn->edge_count() == 0) {
220 ptn->dump();
221 assert(ptn->as_LocalVar()->edge_count() > 0, "sanity");
222 }
223 }
224 _verify = false;
225 }
226 #endif
227 // Bytecode analyzer BCEscapeAnalyzer, used for Call nodes
228 // processing, calls to CI to resolve symbols (types, fields, methods)
229 // referenced in bytecode. During symbol resolution VM may throw
230 // an exception which CI cleans and converts to compilation failure.
231 if (C->failing()) return false;
232
233 // 2. Finish Graph construction by propagating references to all
234 // java objects through graph.
235 if (!complete_connection_graph(ptnodes_worklist, non_escaped_worklist,
236 java_objects_worklist, oop_fields_worklist)) {
237 // All objects escaped or hit time or iterations limits.
238 _collecting = false;
239 return false;
240 }
241
242 // 3. Adjust scalar_replaceable state of nonescaping objects and push
243 // scalar replaceable allocations on alloc_worklist for processing
244 // in split_unique_types().
245 int non_escaped_length = non_escaped_worklist.length();
246 for (int next = 0; next < non_escaped_length; next++) {
247 JavaObjectNode* ptn = non_escaped_worklist.at(next);
248 bool noescape = (ptn->escape_state() == PointsToNode::NoEscape);
249 Node* n = ptn->ideal_node();
250 if (n->is_Allocate()) {
251 n->as_Allocate()->_is_non_escaping = noescape;
252 }
253 if (n->is_CallStaticJava()) {
254 n->as_CallStaticJava()->_is_non_escaping = noescape;
255 }
256 if (noescape && ptn->scalar_replaceable()) {
257 adjust_scalar_replaceable_state(ptn);
258 if (ptn->scalar_replaceable()) {
259 alloc_worklist.append(ptn->ideal_node());
260 }
261 }
262 }
263
264 #ifdef ASSERT
265 if (VerifyConnectionGraph) {
266 // Verify that graph is complete - no new edges could be added or needed.
267 verify_connection_graph(ptnodes_worklist, non_escaped_worklist,
268 java_objects_worklist, addp_worklist);
269 }
270 assert(C->unique() == nodes_size(), "no new ideal nodes should be added during ConnectionGraph build");
271 assert(null_obj->escape_state() == PointsToNode::NoEscape &&
272 null_obj->edge_count() == 0 &&
273 !null_obj->arraycopy_src() &&
274 !null_obj->arraycopy_dst(), "sanity");
275 #endif
276
277 _collecting = false;
278
279 } // TracePhase t3("connectionGraph")
280
281 // 4. Optimize ideal graph based on EA information.
282 bool has_non_escaping_obj = (non_escaped_worklist.length() > 0);
283 if (has_non_escaping_obj) {
284 optimize_ideal_graph(ptr_cmp_worklist, storestore_worklist);
285 }
286
287 #ifndef PRODUCT
288 if (PrintEscapeAnalysis) {
289 dump(ptnodes_worklist); // Dump ConnectionGraph
290 }
291 #endif
292
293 bool has_scalar_replaceable_candidates = (alloc_worklist.length() > 0);
294 #ifdef ASSERT
295 if (VerifyConnectionGraph) {
296 int alloc_length = alloc_worklist.length();
297 for (int next = 0; next < alloc_length; ++next) {
298 Node* n = alloc_worklist.at(next);
299 PointsToNode* ptn = ptnode_adr(n->_idx);
300 assert(ptn->escape_state() == PointsToNode::NoEscape && ptn->scalar_replaceable(), "sanity");
301 }
302 }
303 #endif
304
305 // 5. Separate memory graph for scalar replaceable allcations.
306 if (has_scalar_replaceable_candidates &&
307 C->AliasLevel() >= 3 && EliminateAllocations) {
308 // Now use the escape information to create unique types for
309 // scalar replaceable objects.
310 split_unique_types(alloc_worklist, arraycopy_worklist);
311 if (C->failing()) return false;
312 C->print_method(PHASE_AFTER_EA, 2);
313
314 #ifdef ASSERT
315 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
316 tty->print("=== No allocations eliminated for ");
317 C->method()->print_short_name();
318 if(!EliminateAllocations) {
319 tty->print(" since EliminateAllocations is off ===");
320 } else if(!has_scalar_replaceable_candidates) {
321 tty->print(" since there are no scalar replaceable candidates ===");
322 } else if(C->AliasLevel() < 3) {
323 tty->print(" since AliasLevel < 3 ===");
324 }
325 tty->cr();
326 #endif
327 }
328 return has_non_escaping_obj;
329 }
330
331 // Utility function for nodes that load an object
332 void ConnectionGraph::add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
333 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
334 // ThreadLocal has RawPtr type.
335 const Type* t = _igvn->type(n);
336 if (t->make_ptr() != NULL) {
337 Node* adr = n->in(MemNode::Address);
338 #ifdef ASSERT
339 if (!adr->is_AddP()) {
340 assert(_igvn->type(adr)->isa_rawptr(), "sanity");
341 } else {
342 assert((ptnode_adr(adr->_idx) == NULL ||
343 ptnode_adr(adr->_idx)->as_Field()->is_oop()), "sanity");
344 }
345 #endif
346 add_local_var_and_edge(n, PointsToNode::NoEscape,
347 adr, delayed_worklist);
348 }
349 }
350
351 // Populate Connection Graph with PointsTo nodes and create simple
352 // connection graph edges.
353 void ConnectionGraph::add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist) {
354 assert(!_verify, "this method should not be called for verification");
355 PhaseGVN* igvn = _igvn;
356 uint n_idx = n->_idx;
357 PointsToNode* n_ptn = ptnode_adr(n_idx);
358 if (n_ptn != NULL)
359 return; // No need to redefine PointsTo node during first iteration.
360
361 if (n->is_Call()) {
362 // Arguments to allocation and locking don't escape.
363 if (n->is_AbstractLock()) {
364 // Put Lock and Unlock nodes on IGVN worklist to process them during
365 // first IGVN optimization when escape information is still available.
366 record_for_optimizer(n);
367 } else if (n->is_Allocate()) {
368 add_call_node(n->as_Call());
369 record_for_optimizer(n);
370 } else {
371 if (n->is_CallStaticJava()) {
372 const char* name = n->as_CallStaticJava()->_name;
373 if (name != NULL && strcmp(name, "uncommon_trap") == 0)
374 return; // Skip uncommon traps
375 }
376 // Don't mark as processed since call's arguments have to be processed.
377 delayed_worklist->push(n);
378 // Check if a call returns an object.
379 if ((n->as_Call()->returns_pointer() &&
380 n->as_Call()->proj_out_or_null(TypeFunc::Parms) != NULL) ||
381 (n->is_CallStaticJava() &&
382 n->as_CallStaticJava()->is_boxing_method())) {
383 add_call_node(n->as_Call());
384 }
385 }
386 return;
387 }
388 // Put this check here to process call arguments since some call nodes
389 // point to phantom_obj.
390 if (n_ptn == phantom_obj || n_ptn == null_obj)
391 return; // Skip predefined nodes.
392
393 int opcode = n->Opcode();
394 switch (opcode) {
395 case Op_AddP: {
396 Node* base = get_addp_base(n);
397 PointsToNode* ptn_base = ptnode_adr(base->_idx);
398 // Field nodes are created for all field types. They are used in
399 // adjust_scalar_replaceable_state() and split_unique_types().
400 // Note, non-oop fields will have only base edges in Connection
401 // Graph because such fields are not used for oop loads and stores.
402 int offset = address_offset(n, igvn);
403 add_field(n, PointsToNode::NoEscape, offset);
404 if (ptn_base == NULL) {
405 delayed_worklist->push(n); // Process it later.
406 } else {
407 n_ptn = ptnode_adr(n_idx);
408 add_base(n_ptn->as_Field(), ptn_base);
409 }
410 break;
411 }
412 case Op_CastX2P: {
413 map_ideal_node(n, phantom_obj);
414 break;
415 }
416 case Op_CastPP:
417 case Op_CheckCastPP:
418 case Op_EncodeP:
419 case Op_DecodeN:
420 case Op_EncodePKlass:
421 case Op_DecodeNKlass: {
422 add_local_var_and_edge(n, PointsToNode::NoEscape,
423 n->in(1), delayed_worklist);
424 break;
425 }
426 case Op_CMoveP: {
427 add_local_var(n, PointsToNode::NoEscape);
428 // Do not add edges during first iteration because some could be
429 // not defined yet.
430 delayed_worklist->push(n);
431 break;
432 }
433 case Op_ConP:
434 case Op_ConN:
435 case Op_ConNKlass: {
436 // assume all oop constants globally escape except for null
437 PointsToNode::EscapeState es;
438 const Type* t = igvn->type(n);
439 if (t == TypePtr::NULL_PTR || t == TypeNarrowOop::NULL_PTR) {
440 es = PointsToNode::NoEscape;
441 } else {
442 es = PointsToNode::GlobalEscape;
443 }
444 add_java_object(n, es);
445 break;
446 }
447 case Op_CreateEx: {
448 // assume that all exception objects globally escape
449 map_ideal_node(n, phantom_obj);
450 break;
451 }
452 case Op_LoadKlass:
453 case Op_LoadNKlass: {
454 // Unknown class is loaded
455 map_ideal_node(n, phantom_obj);
456 break;
457 }
458 case Op_LoadP:
459 #if INCLUDE_ZGC
460 case Op_LoadBarrierSlowReg:
461 case Op_LoadBarrierWeakSlowReg:
462 #endif
463 case Op_LoadN:
464 case Op_LoadPLocked: {
465 add_objload_to_connection_graph(n, delayed_worklist);
466 break;
467 }
468 case Op_Parm: {
469 map_ideal_node(n, phantom_obj);
470 break;
471 }
472 case Op_PartialSubtypeCheck: {
473 // Produces Null or notNull and is used in only in CmpP so
474 // phantom_obj could be used.
475 map_ideal_node(n, phantom_obj); // Result is unknown
476 break;
477 }
478 case Op_Phi: {
479 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
480 // ThreadLocal has RawPtr type.
481 const Type* t = n->as_Phi()->type();
482 if (t->make_ptr() != NULL) {
483 add_local_var(n, PointsToNode::NoEscape);
484 // Do not add edges during first iteration because some could be
485 // not defined yet.
486 delayed_worklist->push(n);
487 }
488 break;
489 }
490 case Op_Proj: {
491 // we are only interested in the oop result projection from a call
492 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
493 n->in(0)->as_Call()->returns_pointer()) {
494 add_local_var_and_edge(n, PointsToNode::NoEscape,
495 n->in(0), delayed_worklist);
496 }
497 #if INCLUDE_ZGC
498 else if (UseZGC) {
499 if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) {
500 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), delayed_worklist);
501 }
502 }
503 #endif
504 break;
505 }
506 case Op_Rethrow: // Exception object escapes
507 case Op_Return: {
508 if (n->req() > TypeFunc::Parms &&
509 igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
510 // Treat Return value as LocalVar with GlobalEscape escape state.
511 add_local_var_and_edge(n, PointsToNode::GlobalEscape,
512 n->in(TypeFunc::Parms), delayed_worklist);
513 }
514 break;
515 }
516 case Op_CompareAndExchangeP:
517 case Op_CompareAndExchangeN:
518 #if INCLUDE_SHENANDOAHGC
519 case Op_ShenandoahCompareAndExchangeP:
520 case Op_ShenandoahCompareAndExchangeN:
521 #endif
522 case Op_GetAndSetP:
523 case Op_GetAndSetN: {
524 add_objload_to_connection_graph(n, delayed_worklist);
525 // fallthrough
526 }
527 case Op_StoreP:
528 case Op_StoreN:
529 case Op_StoreNKlass:
530 case Op_StorePConditional:
531 #if INCLUDE_SHENANDOAHGC
532 case Op_ShenandoahWeakCompareAndSwapP:
533 case Op_ShenandoahWeakCompareAndSwapN:
534 case Op_ShenandoahCompareAndSwapP:
535 case Op_ShenandoahCompareAndSwapN:
536 #endif
537 case Op_WeakCompareAndSwapP:
538 case Op_WeakCompareAndSwapN:
539 case Op_CompareAndSwapP:
540 case Op_CompareAndSwapN: {
541 Node* adr = n->in(MemNode::Address);
542 const Type *adr_type = igvn->type(adr);
543 adr_type = adr_type->make_ptr();
544 if (adr_type == NULL) {
545 break; // skip dead nodes
546 }
547 if ( adr_type->isa_oopptr()
548 || ( (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
549 && adr_type == TypeRawPtr::NOTNULL
550 && adr->in(AddPNode::Address)->is_Proj()
551 && adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
552 delayed_worklist->push(n); // Process it later.
553 #ifdef ASSERT
554 assert(adr->is_AddP(), "expecting an AddP");
555 if (adr_type == TypeRawPtr::NOTNULL) {
556 // Verify a raw address for a store captured by Initialize node.
557 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
558 assert(offs != Type::OffsetBot, "offset must be a constant");
559 }
560 #endif
561 } else {
562 // Ignore copy the displaced header to the BoxNode (OSR compilation).
563 if (adr->is_BoxLock())
564 break;
565 // Stored value escapes in unsafe access.
566 if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
567 // Pointer stores in G1 barriers looks like unsafe access.
568 // Ignore such stores to be able scalar replace non-escaping
569 // allocations.
570 #if INCLUDE_G1GC || INCLUDE_SHENANDOAHGC
571 if ((UseG1GC || UseShenandoahGC) && adr->is_AddP()) {
572 Node* base = get_addp_base(adr);
573 if (base->Opcode() == Op_LoadP &&
574 base->in(MemNode::Address)->is_AddP()) {
575 adr = base->in(MemNode::Address);
576 Node* tls = get_addp_base(adr);
577 if (tls->Opcode() == Op_ThreadLocal) {
578 int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
579 #if INCLUDE_G1GC && INCLUDE_SHENANDOAHGC
580 const int buf_offset = in_bytes(UseG1GC ? G1ThreadLocalData::satb_mark_queue_buffer_offset()
581 : ShenandoahThreadLocalData::satb_mark_queue_buffer_offset());
582 #elif INCLUDE_G1GC
583 const int buf_offset = in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset());
584 #else
585 const int buf_offset = in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset());
586 #endif
587 if (offs == buf_offset) {
588 break; // G1 pre barrier previous oop value store.
589 }
590 if (offs == in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset())) {
591 break; // G1 post barrier card address store.
592 }
593 }
594 }
595 }
596 #endif
597 delayed_worklist->push(n); // Process unsafe access later.
598 break;
599 }
600 #ifdef ASSERT
601 n->dump(1);
602 assert(false, "not unsafe or G1 barrier raw StoreP");
603 #endif
604 }
605 break;
606 }
607 case Op_AryEq:
608 case Op_HasNegatives:
609 case Op_StrComp:
610 case Op_StrEquals:
611 case Op_StrIndexOf:
612 case Op_StrIndexOfChar:
613 case Op_StrInflatedCopy:
614 case Op_StrCompressedCopy:
615 case Op_EncodeISOArray: {
616 add_local_var(n, PointsToNode::ArgEscape);
617 delayed_worklist->push(n); // Process it later.
618 break;
619 }
620 case Op_ThreadLocal: {
621 add_java_object(n, PointsToNode::ArgEscape);
622 break;
623 }
624 #if INCLUDE_SHENANDOAHGC
625 case Op_ShenandoahReadBarrier:
626 case Op_ShenandoahWriteBarrier:
627 // Barriers 'pass through' its arguments. I.e. what goes in, comes out.
628 // It doesn't escape.
629 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahBarrierNode::ValueIn), delayed_worklist);
630 break;
631 case Op_ShenandoahEnqueueBarrier:
632 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), delayed_worklist);
633 break;
634 #endif
635 default:
636 ; // Do nothing for nodes not related to EA.
637 }
638 return;
639 }
640
641 #ifdef ASSERT
642 #define ELSE_FAIL(name) \
643 /* Should not be called for not pointer type. */ \
644 n->dump(1); \
645 assert(false, name); \
646 break;
647 #else
648 #define ELSE_FAIL(name) \
649 break;
650 #endif
651
652 // Add final simple edges to graph.
653 void ConnectionGraph::add_final_edges(Node *n) {
654 PointsToNode* n_ptn = ptnode_adr(n->_idx);
655 #ifdef ASSERT
656 if (_verify && n_ptn->is_JavaObject())
657 return; // This method does not change graph for JavaObject.
658 #endif
659
660 if (n->is_Call()) {
661 process_call_arguments(n->as_Call());
662 return;
663 }
664 assert(n->is_Store() || n->is_LoadStore() ||
665 (n_ptn != NULL) && (n_ptn->ideal_node() != NULL),
666 "node should be registered already");
667 int opcode = n->Opcode();
668 switch (opcode) {
669 case Op_AddP: {
670 Node* base = get_addp_base(n);
671 PointsToNode* ptn_base = ptnode_adr(base->_idx);
672 assert(ptn_base != NULL, "field's base should be registered");
673 add_base(n_ptn->as_Field(), ptn_base);
674 break;
675 }
676 case Op_CastPP:
677 case Op_CheckCastPP:
678 case Op_EncodeP:
679 case Op_DecodeN:
680 case Op_EncodePKlass:
681 case Op_DecodeNKlass: {
682 add_local_var_and_edge(n, PointsToNode::NoEscape,
683 n->in(1), NULL);
684 break;
685 }
686 case Op_CMoveP: {
687 for (uint i = CMoveNode::IfFalse; i < n->req(); i++) {
688 Node* in = n->in(i);
689 if (in == NULL)
690 continue; // ignore NULL
691 Node* uncast_in = in->uncast();
692 if (uncast_in->is_top() || uncast_in == n)
693 continue; // ignore top or inputs which go back this node
694 PointsToNode* ptn = ptnode_adr(in->_idx);
695 assert(ptn != NULL, "node should be registered");
696 add_edge(n_ptn, ptn);
697 }
698 break;
699 }
700 case Op_LoadP:
701 #if INCLUDE_ZGC
702 case Op_LoadBarrierSlowReg:
703 case Op_LoadBarrierWeakSlowReg:
704 #endif
705 case Op_LoadN:
706 case Op_LoadPLocked: {
707 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
708 // ThreadLocal has RawPtr type.
709 const Type* t = _igvn->type(n);
710 if (t->make_ptr() != NULL) {
711 Node* adr = n->in(MemNode::Address);
712 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
713 break;
714 }
715 ELSE_FAIL("Op_LoadP");
716 }
717 case Op_Phi: {
718 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
719 // ThreadLocal has RawPtr type.
720 const Type* t = n->as_Phi()->type();
721 if (t->make_ptr() != NULL) {
722 for (uint i = 1; i < n->req(); i++) {
723 Node* in = n->in(i);
724 if (in == NULL)
725 continue; // ignore NULL
726 Node* uncast_in = in->uncast();
727 if (uncast_in->is_top() || uncast_in == n)
728 continue; // ignore top or inputs which go back this node
729 PointsToNode* ptn = ptnode_adr(in->_idx);
730 assert(ptn != NULL, "node should be registered");
731 add_edge(n_ptn, ptn);
732 }
733 break;
734 }
735 ELSE_FAIL("Op_Phi");
736 }
737 case Op_Proj: {
738 // we are only interested in the oop result projection from a call
739 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() &&
740 n->in(0)->as_Call()->returns_pointer()) {
741 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL);
742 break;
743 }
744 #if INCLUDE_ZGC
745 else if (UseZGC) {
746 if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) {
747 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), NULL);
748 break;
749 }
750 }
751 #endif
752 ELSE_FAIL("Op_Proj");
753 }
754 case Op_Rethrow: // Exception object escapes
755 case Op_Return: {
756 if (n->req() > TypeFunc::Parms &&
757 _igvn->type(n->in(TypeFunc::Parms))->isa_oopptr()) {
758 // Treat Return value as LocalVar with GlobalEscape escape state.
759 add_local_var_and_edge(n, PointsToNode::GlobalEscape,
760 n->in(TypeFunc::Parms), NULL);
761 break;
762 }
763 ELSE_FAIL("Op_Return");
764 }
765 case Op_StoreP:
766 case Op_StoreN:
767 case Op_StoreNKlass:
768 case Op_StorePConditional:
769 case Op_CompareAndExchangeP:
770 case Op_CompareAndExchangeN:
771 case Op_CompareAndSwapP:
772 case Op_CompareAndSwapN:
773 case Op_WeakCompareAndSwapP:
774 case Op_WeakCompareAndSwapN:
775 #if INCLUDE_SHENANDOAHGC
776 case Op_ShenandoahCompareAndExchangeP:
777 case Op_ShenandoahCompareAndExchangeN:
778 case Op_ShenandoahCompareAndSwapP:
779 case Op_ShenandoahCompareAndSwapN:
780 case Op_ShenandoahWeakCompareAndSwapP:
781 case Op_ShenandoahWeakCompareAndSwapN:
782 #endif
783 case Op_GetAndSetP:
784 case Op_GetAndSetN: {
785 Node* adr = n->in(MemNode::Address);
786 const Type *adr_type = _igvn->type(adr);
787 adr_type = adr_type->make_ptr();
788 #ifdef ASSERT
789 if (adr_type == NULL) {
790 n->dump(1);
791 assert(adr_type != NULL, "dead node should not be on list");
792 break;
793 }
794 #endif
795 if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN ||
796 #if INCLUDE_SHENANDOAHGC
797 opcode == Op_ShenandoahCompareAndExchangeN || opcode == Op_ShenandoahCompareAndExchangeP ||
798 #endif
799 opcode == Op_CompareAndExchangeN || opcode == Op_CompareAndExchangeP) {
800 add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
801 }
802 if ( adr_type->isa_oopptr()
803 || ( (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
804 && adr_type == TypeRawPtr::NOTNULL
805 && adr->in(AddPNode::Address)->is_Proj()
806 && adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
807 // Point Address to Value
808 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
809 assert(adr_ptn != NULL &&
810 adr_ptn->as_Field()->is_oop(), "node should be registered");
811 Node *val = n->in(MemNode::ValueIn);
812 PointsToNode* ptn = ptnode_adr(val->_idx);
813 assert(ptn != NULL, "node should be registered");
814 add_edge(adr_ptn, ptn);
815 break;
816 } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
817 // Stored value escapes in unsafe access.
818 Node *val = n->in(MemNode::ValueIn);
819 PointsToNode* ptn = ptnode_adr(val->_idx);
820 assert(ptn != NULL, "node should be registered");
821 set_escape_state(ptn, PointsToNode::GlobalEscape);
822 // Add edge to object for unsafe access with offset.
823 PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
824 assert(adr_ptn != NULL, "node should be registered");
825 if (adr_ptn->is_Field()) {
826 assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
827 add_edge(adr_ptn, ptn);
828 }
829 break;
830 }
831 ELSE_FAIL("Op_StoreP");
832 }
833 case Op_AryEq:
834 case Op_HasNegatives:
835 case Op_StrComp:
836 case Op_StrEquals:
837 case Op_StrIndexOf:
838 case Op_StrIndexOfChar:
839 case Op_StrInflatedCopy:
840 case Op_StrCompressedCopy:
841 case Op_EncodeISOArray: {
842 // char[]/byte[] arrays passed to string intrinsic do not escape but
843 // they are not scalar replaceable. Adjust escape state for them.
844 // Start from in(2) edge since in(1) is memory edge.
845 for (uint i = 2; i < n->req(); i++) {
846 Node* adr = n->in(i);
847 const Type* at = _igvn->type(adr);
848 if (!adr->is_top() && at->isa_ptr()) {
849 assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
850 at->isa_ptr() != NULL, "expecting a pointer");
851 if (adr->is_AddP()) {
852 adr = get_addp_base(adr);
853 }
854 PointsToNode* ptn = ptnode_adr(adr->_idx);
855 assert(ptn != NULL, "node should be registered");
856 add_edge(n_ptn, ptn);
857 }
858 }
859 break;
860 }
861 #if INCLUDE_SHENANDOAHGC
862 case Op_ShenandoahReadBarrier:
863 case Op_ShenandoahWriteBarrier:
864 // Barriers 'pass through' its arguments. I.e. what goes in, comes out.
865 // It doesn't escape.
866 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(ShenandoahBarrierNode::ValueIn), NULL);
867 break;
868 case Op_ShenandoahEnqueueBarrier:
869 add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(1), NULL);
870 break;
871 #endif
872 default: {
873 // This method should be called only for EA specific nodes which may
874 // miss some edges when they were created.
875 #ifdef ASSERT
876 n->dump(1);
877 #endif
878 guarantee(false, "unknown node");
879 }
880 }
881 return;
882 }
883
884 void ConnectionGraph::add_call_node(CallNode* call) {
885 assert(call->returns_pointer(), "only for call which returns pointer");
886 uint call_idx = call->_idx;
887 if (call->is_Allocate()) {
888 Node* k = call->in(AllocateNode::KlassNode);
889 const TypeKlassPtr* kt = k->bottom_type()->isa_klassptr();
890 assert(kt != NULL, "TypeKlassPtr required.");
891 ciKlass* cik = kt->klass();
892 PointsToNode::EscapeState es = PointsToNode::NoEscape;
893 bool scalar_replaceable = true;
894 if (call->is_AllocateArray()) {
895 if (!cik->is_array_klass()) { // StressReflectiveCode
896 es = PointsToNode::GlobalEscape;
897 } else {
898 int length = call->in(AllocateNode::ALength)->find_int_con(-1);
899 if (length < 0 || length > EliminateAllocationArraySizeLimit) {
900 // Not scalar replaceable if the length is not constant or too big.
901 scalar_replaceable = false;
902 }
903 }
904 } else { // Allocate instance
905 if (cik->is_subclass_of(_compile->env()->Thread_klass()) ||
906 cik->is_subclass_of(_compile->env()->Reference_klass()) ||
907 !cik->is_instance_klass() || // StressReflectiveCode
908 !cik->as_instance_klass()->can_be_instantiated() ||
909 cik->as_instance_klass()->has_finalizer()) {
910 es = PointsToNode::GlobalEscape;
911 }
912 }
913 add_java_object(call, es);
914 PointsToNode* ptn = ptnode_adr(call_idx);
915 if (!scalar_replaceable && ptn->scalar_replaceable()) {
916 ptn->set_scalar_replaceable(false);
917 }
918 } else if (call->is_CallStaticJava()) {
919 // Call nodes could be different types:
920 //
921 // 1. CallDynamicJavaNode (what happened during call is unknown):
922 //
923 // - mapped to GlobalEscape JavaObject node if oop is returned;
924 //
925 // - all oop arguments are escaping globally;
926 //
927 // 2. CallStaticJavaNode (execute bytecode analysis if possible):
928 //
929 // - the same as CallDynamicJavaNode if can't do bytecode analysis;
930 //
931 // - mapped to GlobalEscape JavaObject node if unknown oop is returned;
932 // - mapped to NoEscape JavaObject node if non-escaping object allocated
933 // during call is returned;
934 // - mapped to ArgEscape LocalVar node pointed to object arguments
935 // which are returned and does not escape during call;
936 //
937 // - oop arguments escaping status is defined by bytecode analysis;
938 //
939 // For a static call, we know exactly what method is being called.
940 // Use bytecode estimator to record whether the call's return value escapes.
941 ciMethod* meth = call->as_CallJava()->method();
942 if (meth == NULL) {
943 const char* name = call->as_CallStaticJava()->_name;
944 assert(strncmp(name, "_multianewarray", 15) == 0, "TODO: add failed case check");
945 // Returns a newly allocated unescaped object.
946 add_java_object(call, PointsToNode::NoEscape);
947 ptnode_adr(call_idx)->set_scalar_replaceable(false);
948 } else if (meth->is_boxing_method()) {
949 // Returns boxing object
950 PointsToNode::EscapeState es;
951 vmIntrinsics::ID intr = meth->intrinsic_id();
952 if (intr == vmIntrinsics::_floatValue || intr == vmIntrinsics::_doubleValue) {
953 // It does not escape if object is always allocated.
954 es = PointsToNode::NoEscape;
955 } else {
956 // It escapes globally if object could be loaded from cache.
957 es = PointsToNode::GlobalEscape;
958 }
959 add_java_object(call, es);
960 } else {
961 BCEscapeAnalyzer* call_analyzer = meth->get_bcea();
962 call_analyzer->copy_dependencies(_compile->dependencies());
963 if (call_analyzer->is_return_allocated()) {
964 // Returns a newly allocated unescaped object, simply
965 // update dependency information.
966 // Mark it as NoEscape so that objects referenced by
967 // it's fields will be marked as NoEscape at least.
968 add_java_object(call, PointsToNode::NoEscape);
969 ptnode_adr(call_idx)->set_scalar_replaceable(false);
970 } else {
971 // Determine whether any arguments are returned.
972 const TypeTuple* d = call->tf()->domain();
973 bool ret_arg = false;
974 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
975 if (d->field_at(i)->isa_ptr() != NULL &&
976 call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
977 ret_arg = true;
978 break;
979 }
980 }
981 if (ret_arg) {
982 add_local_var(call, PointsToNode::ArgEscape);
983 } else {
984 // Returns unknown object.
985 map_ideal_node(call, phantom_obj);
986 }
987 }
988 }
989 } else {
990 // An other type of call, assume the worst case:
991 // returned value is unknown and globally escapes.
992 assert(call->Opcode() == Op_CallDynamicJava, "add failed case check");
993 map_ideal_node(call, phantom_obj);
994 }
995 }
996
997 void ConnectionGraph::process_call_arguments(CallNode *call) {
998 bool is_arraycopy = false;
999 switch (call->Opcode()) {
1000 #ifdef ASSERT
1001 case Op_Allocate:
1002 case Op_AllocateArray:
1003 case Op_Lock:
1004 case Op_Unlock:
1005 assert(false, "should be done already");
1006 break;
1007 #endif
1008 case Op_ArrayCopy:
1009 case Op_CallLeafNoFP:
1010 // Most array copies are ArrayCopy nodes at this point but there
1011 // are still a few direct calls to the copy subroutines (See
1012 // PhaseStringOpts::copy_string())
1013 is_arraycopy = (call->Opcode() == Op_ArrayCopy) ||
1014 call->as_CallLeaf()->is_call_to_arraycopystub();
1015 // fall through
1016 case Op_CallLeaf: {
1017 // Stub calls, objects do not escape but they are not scale replaceable.
1018 // Adjust escape state for outgoing arguments.
1019 const TypeTuple * d = call->tf()->domain();
1020 bool src_has_oops = false;
1021 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1022 const Type* at = d->field_at(i);
1023 Node *arg = call->in(i);
1024 if (arg == NULL) {
1025 continue;
1026 }
1027 const Type *aat = _igvn->type(arg);
1028 if (arg->is_top() || !at->isa_ptr() || !aat->isa_ptr())
1029 continue;
1030 if (arg->is_AddP()) {
1031 //
1032 // The inline_native_clone() case when the arraycopy stub is called
1033 // after the allocation before Initialize and CheckCastPP nodes.
1034 // Or normal arraycopy for object arrays case.
1035 //
1036 // Set AddP's base (Allocate) as not scalar replaceable since
1037 // pointer to the base (with offset) is passed as argument.
1038 //
1039 arg = get_addp_base(arg);
1040 }
1041 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1042 assert(arg_ptn != NULL, "should be registered");
1043 PointsToNode::EscapeState arg_esc = arg_ptn->escape_state();
1044 if (is_arraycopy || arg_esc < PointsToNode::ArgEscape) {
1045 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
1046 aat->isa_ptr() != NULL, "expecting an Ptr");
1047 bool arg_has_oops = aat->isa_oopptr() &&
1048 (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() ||
1049 (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass()));
1050 if (i == TypeFunc::Parms) {
1051 src_has_oops = arg_has_oops;
1052 }
1053 //
1054 // src or dst could be j.l.Object when other is basic type array:
1055 //
1056 // arraycopy(char[],0,Object*,0,size);
1057 // arraycopy(Object*,0,char[],0,size);
1058 //
1059 // Don't add edges in such cases.
1060 //
1061 bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy &&
1062 arg_has_oops && (i > TypeFunc::Parms);
1063 #ifdef ASSERT
1064 if (!(is_arraycopy ||
1065 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(call) ||
1066 (call->as_CallLeaf()->_name != NULL &&
1067 (strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32") == 0 ||
1068 strcmp(call->as_CallLeaf()->_name, "updateBytesCRC32C") == 0 ||
1069 strcmp(call->as_CallLeaf()->_name, "updateBytesAdler32") == 0 ||
1070 strcmp(call->as_CallLeaf()->_name, "aescrypt_encryptBlock") == 0 ||
1071 strcmp(call->as_CallLeaf()->_name, "aescrypt_decryptBlock") == 0 ||
1072 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_encryptAESCrypt") == 0 ||
1073 strcmp(call->as_CallLeaf()->_name, "cipherBlockChaining_decryptAESCrypt") == 0 ||
1074 strcmp(call->as_CallLeaf()->_name, "counterMode_AESCrypt") == 0 ||
1075 strcmp(call->as_CallLeaf()->_name, "ghash_processBlocks") == 0 ||
1076 strcmp(call->as_CallLeaf()->_name, "encodeBlock") == 0 ||
1077 strcmp(call->as_CallLeaf()->_name, "sha1_implCompress") == 0 ||
1078 strcmp(call->as_CallLeaf()->_name, "sha1_implCompressMB") == 0 ||
1079 strcmp(call->as_CallLeaf()->_name, "sha256_implCompress") == 0 ||
1080 strcmp(call->as_CallLeaf()->_name, "sha256_implCompressMB") == 0 ||
1081 strcmp(call->as_CallLeaf()->_name, "sha512_implCompress") == 0 ||
1082 strcmp(call->as_CallLeaf()->_name, "sha512_implCompressMB") == 0 ||
1083 strcmp(call->as_CallLeaf()->_name, "multiplyToLen") == 0 ||
1084 strcmp(call->as_CallLeaf()->_name, "squareToLen") == 0 ||
1085 strcmp(call->as_CallLeaf()->_name, "mulAdd") == 0 ||
1086 strcmp(call->as_CallLeaf()->_name, "montgomery_multiply") == 0 ||
1087 strcmp(call->as_CallLeaf()->_name, "montgomery_square") == 0 ||
1088 strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0)
1089 ))) {
1090 call->dump();
1091 fatal("EA unexpected CallLeaf %s", call->as_CallLeaf()->_name);
1092 }
1093 #endif
1094 // Always process arraycopy's destination object since
1095 // we need to add all possible edges to references in
1096 // source object.
1097 if (arg_esc >= PointsToNode::ArgEscape &&
1098 !arg_is_arraycopy_dest) {
1099 continue;
1100 }
1101 PointsToNode::EscapeState es = PointsToNode::ArgEscape;
1102 if (call->is_ArrayCopy()) {
1103 ArrayCopyNode* ac = call->as_ArrayCopy();
1104 if (ac->is_clonebasic() ||
1105 ac->is_arraycopy_validated() ||
1106 ac->is_copyof_validated() ||
1107 ac->is_copyofrange_validated()) {
1108 es = PointsToNode::NoEscape;
1109 }
1110 }
1111 set_escape_state(arg_ptn, es);
1112 if (arg_is_arraycopy_dest) {
1113 Node* src = call->in(TypeFunc::Parms);
1114 if (src->is_AddP()) {
1115 src = get_addp_base(src);
1116 }
1117 PointsToNode* src_ptn = ptnode_adr(src->_idx);
1118 assert(src_ptn != NULL, "should be registered");
1119 if (arg_ptn != src_ptn) {
1120 // Special arraycopy edge:
1121 // A destination object's field can't have the source object
1122 // as base since objects escape states are not related.
1123 // Only escape state of destination object's fields affects
1124 // escape state of fields in source object.
1125 add_arraycopy(call, es, src_ptn, arg_ptn);
1126 }
1127 }
1128 }
1129 }
1130 break;
1131 }
1132 case Op_CallStaticJava: {
1133 // For a static call, we know exactly what method is being called.
1134 // Use bytecode estimator to record the call's escape affects
1135 #ifdef ASSERT
1136 const char* name = call->as_CallStaticJava()->_name;
1137 assert((name == NULL || strcmp(name, "uncommon_trap") != 0), "normal calls only");
1138 #endif
1139 ciMethod* meth = call->as_CallJava()->method();
1140 if ((meth != NULL) && meth->is_boxing_method()) {
1141 break; // Boxing methods do not modify any oops.
1142 }
1143 BCEscapeAnalyzer* call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
1144 // fall-through if not a Java method or no analyzer information
1145 if (call_analyzer != NULL) {
1146 PointsToNode* call_ptn = ptnode_adr(call->_idx);
1147 const TypeTuple* d = call->tf()->domain();
1148 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1149 const Type* at = d->field_at(i);
1150 int k = i - TypeFunc::Parms;
1151 Node* arg = call->in(i);
1152 PointsToNode* arg_ptn = ptnode_adr(arg->_idx);
1153 if (at->isa_ptr() != NULL &&
1154 call_analyzer->is_arg_returned(k)) {
1155 // The call returns arguments.
1156 if (call_ptn != NULL) { // Is call's result used?
1157 assert(call_ptn->is_LocalVar(), "node should be registered");
1158 assert(arg_ptn != NULL, "node should be registered");
1159 add_edge(call_ptn, arg_ptn);
1160 }
1161 }
1162 if (at->isa_oopptr() != NULL &&
1163 arg_ptn->escape_state() < PointsToNode::GlobalEscape) {
1164 if (!call_analyzer->is_arg_stack(k)) {
1165 // The argument global escapes
1166 set_escape_state(arg_ptn, PointsToNode::GlobalEscape);
1167 } else {
1168 set_escape_state(arg_ptn, PointsToNode::ArgEscape);
1169 if (!call_analyzer->is_arg_local(k)) {
1170 // The argument itself doesn't escape, but any fields might
1171 set_fields_escape_state(arg_ptn, PointsToNode::GlobalEscape);
1172 }
1173 }
1174 }
1175 }
1176 if (call_ptn != NULL && call_ptn->is_LocalVar()) {
1177 // The call returns arguments.
1178 assert(call_ptn->edge_count() > 0, "sanity");
1179 if (!call_analyzer->is_return_local()) {
1180 // Returns also unknown object.
1181 add_edge(call_ptn, phantom_obj);
1182 }
1183 }
1184 break;
1185 }
1186 }
1187 default: {
1188 // Fall-through here if not a Java method or no analyzer information
1189 // or some other type of call, assume the worst case: all arguments
1190 // globally escape.
1191 const TypeTuple* d = call->tf()->domain();
1192 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1193 const Type* at = d->field_at(i);
1194 if (at->isa_oopptr() != NULL) {
1195 Node* arg = call->in(i);
1196 if (arg->is_AddP()) {
1197 arg = get_addp_base(arg);
1198 }
1199 assert(ptnode_adr(arg->_idx) != NULL, "should be defined already");
1200 set_escape_state(ptnode_adr(arg->_idx), PointsToNode::GlobalEscape);
1201 }
1202 }
1203 }
1204 }
1205 }
1206
1207
1208 // Finish Graph construction.
1209 bool ConnectionGraph::complete_connection_graph(
1210 GrowableArray<PointsToNode*>& ptnodes_worklist,
1211 GrowableArray<JavaObjectNode*>& non_escaped_worklist,
1212 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1213 GrowableArray<FieldNode*>& oop_fields_worklist) {
1214 // Normally only 1-3 passes needed to build Connection Graph depending
1215 // on graph complexity. Observed 8 passes in jvm2008 compiler.compiler.
1216 // Set limit to 20 to catch situation when something did go wrong and
1217 // bailout Escape Analysis.
1218 // Also limit build time to 20 sec (60 in debug VM), EscapeAnalysisTimeout flag.
1219 #define CG_BUILD_ITER_LIMIT 20
1220
1221 // Propagate GlobalEscape and ArgEscape escape states and check that
1222 // we still have non-escaping objects. The method pushs on _worklist
1223 // Field nodes which reference phantom_object.
1224 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) {
1225 return false; // Nothing to do.
1226 }
1227 // Now propagate references to all JavaObject nodes.
1228 int java_objects_length = java_objects_worklist.length();
1229 elapsedTimer time;
1230 bool timeout = false;
1231 int new_edges = 1;
1232 int iterations = 0;
1233 do {
1234 while ((new_edges > 0) &&
1235 (iterations++ < CG_BUILD_ITER_LIMIT)) {
1236 double start_time = time.seconds();
1237 time.start();
1238 new_edges = 0;
1239 // Propagate references to phantom_object for nodes pushed on _worklist
1240 // by find_non_escaped_objects() and find_field_value().
1241 new_edges += add_java_object_edges(phantom_obj, false);
1242 for (int next = 0; next < java_objects_length; ++next) {
1243 JavaObjectNode* ptn = java_objects_worklist.at(next);
1244 new_edges += add_java_object_edges(ptn, true);
1245
1246 #define SAMPLE_SIZE 4
1247 if ((next % SAMPLE_SIZE) == 0) {
1248 // Each 4 iterations calculate how much time it will take
1249 // to complete graph construction.
1250 time.stop();
1251 // Poll for requests from shutdown mechanism to quiesce compiler
1252 // because Connection graph construction may take long time.
1253 CompileBroker::maybe_block();
1254 double stop_time = time.seconds();
1255 double time_per_iter = (stop_time - start_time) / (double)SAMPLE_SIZE;
1256 double time_until_end = time_per_iter * (double)(java_objects_length - next);
1257 if ((start_time + time_until_end) >= EscapeAnalysisTimeout) {
1258 timeout = true;
1259 break; // Timeout
1260 }
1261 start_time = stop_time;
1262 time.start();
1263 }
1264 #undef SAMPLE_SIZE
1265
1266 }
1267 if (timeout) break;
1268 if (new_edges > 0) {
1269 // Update escape states on each iteration if graph was updated.
1270 if (!find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist)) {
1271 return false; // Nothing to do.
1272 }
1273 }
1274 time.stop();
1275 if (time.seconds() >= EscapeAnalysisTimeout) {
1276 timeout = true;
1277 break;
1278 }
1279 }
1280 if ((iterations < CG_BUILD_ITER_LIMIT) && !timeout) {
1281 time.start();
1282 // Find fields which have unknown value.
1283 int fields_length = oop_fields_worklist.length();
1284 for (int next = 0; next < fields_length; next++) {
1285 FieldNode* field = oop_fields_worklist.at(next);
1286 if (field->edge_count() == 0) {
1287 new_edges += find_field_value(field);
1288 // This code may added new edges to phantom_object.
1289 // Need an other cycle to propagate references to phantom_object.
1290 }
1291 }
1292 time.stop();
1293 if (time.seconds() >= EscapeAnalysisTimeout) {
1294 timeout = true;
1295 break;
1296 }
1297 } else {
1298 new_edges = 0; // Bailout
1299 }
1300 } while (new_edges > 0);
1301
1302 // Bailout if passed limits.
1303 if ((iterations >= CG_BUILD_ITER_LIMIT) || timeout) {
1304 Compile* C = _compile;
1305 if (C->log() != NULL) {
1306 C->log()->begin_elem("connectionGraph_bailout reason='reached ");
1307 C->log()->text("%s", timeout ? "time" : "iterations");
1308 C->log()->end_elem(" limit'");
1309 }
1310 assert(ExitEscapeAnalysisOnTimeout, "infinite EA connection graph build (%f sec, %d iterations) with %d nodes and worklist size %d",
1311 time.seconds(), iterations, nodes_size(), ptnodes_worklist.length());
1312 // Possible infinite build_connection_graph loop,
1313 // bailout (no changes to ideal graph were made).
1314 return false;
1315 }
1316 #ifdef ASSERT
1317 if (Verbose && PrintEscapeAnalysis) {
1318 tty->print_cr("EA: %d iterations to build connection graph with %d nodes and worklist size %d",
1319 iterations, nodes_size(), ptnodes_worklist.length());
1320 }
1321 #endif
1322
1323 #undef CG_BUILD_ITER_LIMIT
1324
1325 // Find fields initialized by NULL for non-escaping Allocations.
1326 int non_escaped_length = non_escaped_worklist.length();
1327 for (int next = 0; next < non_escaped_length; next++) {
1328 JavaObjectNode* ptn = non_escaped_worklist.at(next);
1329 PointsToNode::EscapeState es = ptn->escape_state();
1330 assert(es <= PointsToNode::ArgEscape, "sanity");
1331 if (es == PointsToNode::NoEscape) {
1332 if (find_init_values(ptn, null_obj, _igvn) > 0) {
1333 // Adding references to NULL object does not change escape states
1334 // since it does not escape. Also no fields are added to NULL object.
1335 add_java_object_edges(null_obj, false);
1336 }
1337 }
1338 Node* n = ptn->ideal_node();
1339 if (n->is_Allocate()) {
1340 // The object allocated by this Allocate node will never be
1341 // seen by an other thread. Mark it so that when it is
1342 // expanded no MemBarStoreStore is added.
1343 InitializeNode* ini = n->as_Allocate()->initialization();
1344 if (ini != NULL)
1345 ini->set_does_not_escape();
1346 }
1347 }
1348 return true; // Finished graph construction.
1349 }
1350
1351 // Propagate GlobalEscape and ArgEscape escape states to all nodes
1352 // and check that we still have non-escaping java objects.
1353 bool ConnectionGraph::find_non_escaped_objects(GrowableArray<PointsToNode*>& ptnodes_worklist,
1354 GrowableArray<JavaObjectNode*>& non_escaped_worklist) {
1355 GrowableArray<PointsToNode*> escape_worklist;
1356 // First, put all nodes with GlobalEscape and ArgEscape states on worklist.
1357 int ptnodes_length = ptnodes_worklist.length();
1358 for (int next = 0; next < ptnodes_length; ++next) {
1359 PointsToNode* ptn = ptnodes_worklist.at(next);
1360 if (ptn->escape_state() >= PointsToNode::ArgEscape ||
1361 ptn->fields_escape_state() >= PointsToNode::ArgEscape) {
1362 escape_worklist.push(ptn);
1363 }
1364 }
1365 // Set escape states to referenced nodes (edges list).
1366 while (escape_worklist.length() > 0) {
1367 PointsToNode* ptn = escape_worklist.pop();
1368 PointsToNode::EscapeState es = ptn->escape_state();
1369 PointsToNode::EscapeState field_es = ptn->fields_escape_state();
1370 if (ptn->is_Field() && ptn->as_Field()->is_oop() &&
1371 es >= PointsToNode::ArgEscape) {
1372 // GlobalEscape or ArgEscape state of field means it has unknown value.
1373 if (add_edge(ptn, phantom_obj)) {
1374 // New edge was added
1375 add_field_uses_to_worklist(ptn->as_Field());
1376 }
1377 }
1378 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1379 PointsToNode* e = i.get();
1380 if (e->is_Arraycopy()) {
1381 assert(ptn->arraycopy_dst(), "sanity");
1382 // Propagate only fields escape state through arraycopy edge.
1383 if (e->fields_escape_state() < field_es) {
1384 set_fields_escape_state(e, field_es);
1385 escape_worklist.push(e);
1386 }
1387 } else if (es >= field_es) {
1388 // fields_escape_state is also set to 'es' if it is less than 'es'.
1389 if (e->escape_state() < es) {
1390 set_escape_state(e, es);
1391 escape_worklist.push(e);
1392 }
1393 } else {
1394 // Propagate field escape state.
1395 bool es_changed = false;
1396 if (e->fields_escape_state() < field_es) {
1397 set_fields_escape_state(e, field_es);
1398 es_changed = true;
1399 }
1400 if ((e->escape_state() < field_es) &&
1401 e->is_Field() && ptn->is_JavaObject() &&
1402 e->as_Field()->is_oop()) {
1403 // Change escape state of referenced fields.
1404 set_escape_state(e, field_es);
1405 es_changed = true;
1406 } else if (e->escape_state() < es) {
1407 set_escape_state(e, es);
1408 es_changed = true;
1409 }
1410 if (es_changed) {
1411 escape_worklist.push(e);
1412 }
1413 }
1414 }
1415 }
1416 // Remove escaped objects from non_escaped list.
1417 for (int next = non_escaped_worklist.length()-1; next >= 0 ; --next) {
1418 JavaObjectNode* ptn = non_escaped_worklist.at(next);
1419 if (ptn->escape_state() >= PointsToNode::GlobalEscape) {
1420 non_escaped_worklist.delete_at(next);
1421 }
1422 if (ptn->escape_state() == PointsToNode::NoEscape) {
1423 // Find fields in non-escaped allocations which have unknown value.
1424 find_init_values(ptn, phantom_obj, NULL);
1425 }
1426 }
1427 return (non_escaped_worklist.length() > 0);
1428 }
1429
1430 // Add all references to JavaObject node by walking over all uses.
1431 int ConnectionGraph::add_java_object_edges(JavaObjectNode* jobj, bool populate_worklist) {
1432 int new_edges = 0;
1433 if (populate_worklist) {
1434 // Populate _worklist by uses of jobj's uses.
1435 for (UseIterator i(jobj); i.has_next(); i.next()) {
1436 PointsToNode* use = i.get();
1437 if (use->is_Arraycopy())
1438 continue;
1439 add_uses_to_worklist(use);
1440 if (use->is_Field() && use->as_Field()->is_oop()) {
1441 // Put on worklist all field's uses (loads) and
1442 // related field nodes (same base and offset).
1443 add_field_uses_to_worklist(use->as_Field());
1444 }
1445 }
1446 }
1447 for (int l = 0; l < _worklist.length(); l++) {
1448 PointsToNode* use = _worklist.at(l);
1449 if (PointsToNode::is_base_use(use)) {
1450 // Add reference from jobj to field and from field to jobj (field's base).
1451 use = PointsToNode::get_use_node(use)->as_Field();
1452 if (add_base(use->as_Field(), jobj)) {
1453 new_edges++;
1454 }
1455 continue;
1456 }
1457 assert(!use->is_JavaObject(), "sanity");
1458 if (use->is_Arraycopy()) {
1459 if (jobj == null_obj) // NULL object does not have field edges
1460 continue;
1461 // Added edge from Arraycopy node to arraycopy's source java object
1462 if (add_edge(use, jobj)) {
1463 jobj->set_arraycopy_src();
1464 new_edges++;
1465 }
1466 // and stop here.
1467 continue;
1468 }
1469 if (!add_edge(use, jobj))
1470 continue; // No new edge added, there was such edge already.
1471 new_edges++;
1472 if (use->is_LocalVar()) {
1473 add_uses_to_worklist(use);
1474 if (use->arraycopy_dst()) {
1475 for (EdgeIterator i(use); i.has_next(); i.next()) {
1476 PointsToNode* e = i.get();
1477 if (e->is_Arraycopy()) {
1478 if (jobj == null_obj) // NULL object does not have field edges
1479 continue;
1480 // Add edge from arraycopy's destination java object to Arraycopy node.
1481 if (add_edge(jobj, e)) {
1482 new_edges++;
1483 jobj->set_arraycopy_dst();
1484 }
1485 }
1486 }
1487 }
1488 } else {
1489 // Added new edge to stored in field values.
1490 // Put on worklist all field's uses (loads) and
1491 // related field nodes (same base and offset).
1492 add_field_uses_to_worklist(use->as_Field());
1493 }
1494 }
1495 _worklist.clear();
1496 _in_worklist.Reset();
1497 return new_edges;
1498 }
1499
1500 // Put on worklist all related field nodes.
1501 void ConnectionGraph::add_field_uses_to_worklist(FieldNode* field) {
1502 assert(field->is_oop(), "sanity");
1503 int offset = field->offset();
1504 add_uses_to_worklist(field);
1505 // Loop over all bases of this field and push on worklist Field nodes
1506 // with the same offset and base (since they may reference the same field).
1507 for (BaseIterator i(field); i.has_next(); i.next()) {
1508 PointsToNode* base = i.get();
1509 add_fields_to_worklist(field, base);
1510 // Check if the base was source object of arraycopy and go over arraycopy's
1511 // destination objects since values stored to a field of source object are
1512 // accessable by uses (loads) of fields of destination objects.
1513 if (base->arraycopy_src()) {
1514 for (UseIterator j(base); j.has_next(); j.next()) {
1515 PointsToNode* arycp = j.get();
1516 if (arycp->is_Arraycopy()) {
1517 for (UseIterator k(arycp); k.has_next(); k.next()) {
1518 PointsToNode* abase = k.get();
1519 if (abase->arraycopy_dst() && abase != base) {
1520 // Look for the same arraycopy reference.
1521 add_fields_to_worklist(field, abase);
1522 }
1523 }
1524 }
1525 }
1526 }
1527 }
1528 }
1529
1530 // Put on worklist all related field nodes.
1531 void ConnectionGraph::add_fields_to_worklist(FieldNode* field, PointsToNode* base) {
1532 int offset = field->offset();
1533 if (base->is_LocalVar()) {
1534 for (UseIterator j(base); j.has_next(); j.next()) {
1535 PointsToNode* f = j.get();
1536 if (PointsToNode::is_base_use(f)) { // Field
1537 f = PointsToNode::get_use_node(f);
1538 if (f == field || !f->as_Field()->is_oop())
1539 continue;
1540 int offs = f->as_Field()->offset();
1541 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1542 add_to_worklist(f);
1543 }
1544 }
1545 }
1546 } else {
1547 assert(base->is_JavaObject(), "sanity");
1548 if (// Skip phantom_object since it is only used to indicate that
1549 // this field's content globally escapes.
1550 (base != phantom_obj) &&
1551 // NULL object node does not have fields.
1552 (base != null_obj)) {
1553 for (EdgeIterator i(base); i.has_next(); i.next()) {
1554 PointsToNode* f = i.get();
1555 // Skip arraycopy edge since store to destination object field
1556 // does not update value in source object field.
1557 if (f->is_Arraycopy()) {
1558 assert(base->arraycopy_dst(), "sanity");
1559 continue;
1560 }
1561 if (f == field || !f->as_Field()->is_oop())
1562 continue;
1563 int offs = f->as_Field()->offset();
1564 if (offs == offset || offset == Type::OffsetBot || offs == Type::OffsetBot) {
1565 add_to_worklist(f);
1566 }
1567 }
1568 }
1569 }
1570 }
1571
1572 // Find fields which have unknown value.
1573 int ConnectionGraph::find_field_value(FieldNode* field) {
1574 // Escaped fields should have init value already.
1575 assert(field->escape_state() == PointsToNode::NoEscape, "sanity");
1576 int new_edges = 0;
1577 for (BaseIterator i(field); i.has_next(); i.next()) {
1578 PointsToNode* base = i.get();
1579 if (base->is_JavaObject()) {
1580 // Skip Allocate's fields which will be processed later.
1581 if (base->ideal_node()->is_Allocate())
1582 return 0;
1583 assert(base == null_obj, "only NULL ptr base expected here");
1584 }
1585 }
1586 if (add_edge(field, phantom_obj)) {
1587 // New edge was added
1588 new_edges++;
1589 add_field_uses_to_worklist(field);
1590 }
1591 return new_edges;
1592 }
1593
1594 // Find fields initializing values for allocations.
1595 int ConnectionGraph::find_init_values(JavaObjectNode* pta, PointsToNode* init_val, PhaseTransform* phase) {
1596 assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
1597 int new_edges = 0;
1598 Node* alloc = pta->ideal_node();
1599 if (init_val == phantom_obj) {
1600 // Do nothing for Allocate nodes since its fields values are
1601 // "known" unless they are initialized by arraycopy/clone.
1602 if (alloc->is_Allocate() && !pta->arraycopy_dst())
1603 return 0;
1604 assert(pta->arraycopy_dst() || alloc->as_CallStaticJava(), "sanity");
1605 #ifdef ASSERT
1606 if (!pta->arraycopy_dst() && alloc->as_CallStaticJava()->method() == NULL) {
1607 const char* name = alloc->as_CallStaticJava()->_name;
1608 assert(strncmp(name, "_multianewarray", 15) == 0, "sanity");
1609 }
1610 #endif
1611 // Non-escaped allocation returned from Java or runtime call have
1612 // unknown values in fields.
1613 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1614 PointsToNode* field = i.get();
1615 if (field->is_Field() && field->as_Field()->is_oop()) {
1616 if (add_edge(field, phantom_obj)) {
1617 // New edge was added
1618 new_edges++;
1619 add_field_uses_to_worklist(field->as_Field());
1620 }
1621 }
1622 }
1623 return new_edges;
1624 }
1625 assert(init_val == null_obj, "sanity");
1626 // Do nothing for Call nodes since its fields values are unknown.
1627 if (!alloc->is_Allocate())
1628 return 0;
1629
1630 InitializeNode* ini = alloc->as_Allocate()->initialization();
1631 bool visited_bottom_offset = false;
1632 GrowableArray<int> offsets_worklist;
1633
1634 // Check if an oop field's initializing value is recorded and add
1635 // a corresponding NULL if field's value if it is not recorded.
1636 // Connection Graph does not record a default initialization by NULL
1637 // captured by Initialize node.
1638 //
1639 for (EdgeIterator i(pta); i.has_next(); i.next()) {
1640 PointsToNode* field = i.get(); // Field (AddP)
1641 if (!field->is_Field() || !field->as_Field()->is_oop())
1642 continue; // Not oop field
1643 int offset = field->as_Field()->offset();
1644 if (offset == Type::OffsetBot) {
1645 if (!visited_bottom_offset) {
1646 // OffsetBot is used to reference array's element,
1647 // always add reference to NULL to all Field nodes since we don't
1648 // known which element is referenced.
1649 if (add_edge(field, null_obj)) {
1650 // New edge was added
1651 new_edges++;
1652 add_field_uses_to_worklist(field->as_Field());
1653 visited_bottom_offset = true;
1654 }
1655 }
1656 } else {
1657 // Check only oop fields.
1658 const Type* adr_type = field->ideal_node()->as_AddP()->bottom_type();
1659 if (adr_type->isa_rawptr()) {
1660 #ifdef ASSERT
1661 // Raw pointers are used for initializing stores so skip it
1662 // since it should be recorded already
1663 Node* base = get_addp_base(field->ideal_node());
1664 assert(adr_type->isa_rawptr() && base->is_Proj() &&
1665 (base->in(0) == alloc),"unexpected pointer type");
1666 #endif
1667 continue;
1668 }
1669 if (!offsets_worklist.contains(offset)) {
1670 offsets_worklist.append(offset);
1671 Node* value = NULL;
1672 if (ini != NULL) {
1673 // StoreP::memory_type() == T_ADDRESS
1674 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_ADDRESS;
1675 Node* store = ini->find_captured_store(offset, type2aelembytes(ft, true), phase);
1676 // Make sure initializing store has the same type as this AddP.
1677 // This AddP may reference non existing field because it is on a
1678 // dead branch of bimorphic call which is not eliminated yet.
1679 if (store != NULL && store->is_Store() &&
1680 store->as_Store()->memory_type() == ft) {
1681 value = store->in(MemNode::ValueIn);
1682 #ifdef ASSERT
1683 if (VerifyConnectionGraph) {
1684 // Verify that AddP already points to all objects the value points to.
1685 PointsToNode* val = ptnode_adr(value->_idx);
1686 assert((val != NULL), "should be processed already");
1687 PointsToNode* missed_obj = NULL;
1688 if (val->is_JavaObject()) {
1689 if (!field->points_to(val->as_JavaObject())) {
1690 missed_obj = val;
1691 }
1692 } else {
1693 if (!val->is_LocalVar() || (val->edge_count() == 0)) {
1694 tty->print_cr("----------init store has invalid value -----");
1695 store->dump();
1696 val->dump();
1697 assert(val->is_LocalVar() && (val->edge_count() > 0), "should be processed already");
1698 }
1699 for (EdgeIterator j(val); j.has_next(); j.next()) {
1700 PointsToNode* obj = j.get();
1701 if (obj->is_JavaObject()) {
1702 if (!field->points_to(obj->as_JavaObject())) {
1703 missed_obj = obj;
1704 break;
1705 }
1706 }
1707 }
1708 }
1709 if (missed_obj != NULL) {
1710 tty->print_cr("----------field---------------------------------");
1711 field->dump();
1712 tty->print_cr("----------missed referernce to object-----------");
1713 missed_obj->dump();
1714 tty->print_cr("----------object referernced by init store -----");
1715 store->dump();
1716 val->dump();
1717 assert(!field->points_to(missed_obj->as_JavaObject()), "missed JavaObject reference");
1718 }
1719 }
1720 #endif
1721 } else {
1722 // There could be initializing stores which follow allocation.
1723 // For example, a volatile field store is not collected
1724 // by Initialize node.
1725 //
1726 // Need to check for dependent loads to separate such stores from
1727 // stores which follow loads. For now, add initial value NULL so
1728 // that compare pointers optimization works correctly.
1729 }
1730 }
1731 if (value == NULL) {
1732 // A field's initializing value was not recorded. Add NULL.
1733 if (add_edge(field, null_obj)) {
1734 // New edge was added
1735 new_edges++;
1736 add_field_uses_to_worklist(field->as_Field());
1737 }
1738 }
1739 }
1740 }
1741 }
1742 return new_edges;
1743 }
1744
1745 // Adjust scalar_replaceable state after Connection Graph is built.
1746 void ConnectionGraph::adjust_scalar_replaceable_state(JavaObjectNode* jobj) {
1747 // Search for non-escaping objects which are not scalar replaceable
1748 // and mark them to propagate the state to referenced objects.
1749
1750 // 1. An object is not scalar replaceable if the field into which it is
1751 // stored has unknown offset (stored into unknown element of an array).
1752 //
1753 for (UseIterator i(jobj); i.has_next(); i.next()) {
1754 PointsToNode* use = i.get();
1755 if (use->is_Arraycopy()) {
1756 continue;
1757 }
1758 if (use->is_Field()) {
1759 FieldNode* field = use->as_Field();
1760 assert(field->is_oop() && field->scalar_replaceable(), "sanity");
1761 if (field->offset() == Type::OffsetBot) {
1762 jobj->set_scalar_replaceable(false);
1763 return;
1764 }
1765 // 2. An object is not scalar replaceable if the field into which it is
1766 // stored has multiple bases one of which is null.
1767 if (field->base_count() > 1) {
1768 for (BaseIterator i(field); i.has_next(); i.next()) {
1769 PointsToNode* base = i.get();
1770 if (base == null_obj) {
1771 jobj->set_scalar_replaceable(false);
1772 return;
1773 }
1774 }
1775 }
1776 }
1777 assert(use->is_Field() || use->is_LocalVar(), "sanity");
1778 // 3. An object is not scalar replaceable if it is merged with other objects.
1779 for (EdgeIterator j(use); j.has_next(); j.next()) {
1780 PointsToNode* ptn = j.get();
1781 if (ptn->is_JavaObject() && ptn != jobj) {
1782 // Mark all objects.
1783 jobj->set_scalar_replaceable(false);
1784 ptn->set_scalar_replaceable(false);
1785 }
1786 }
1787 if (!jobj->scalar_replaceable()) {
1788 return;
1789 }
1790 }
1791
1792 for (EdgeIterator j(jobj); j.has_next(); j.next()) {
1793 if (j.get()->is_Arraycopy()) {
1794 continue;
1795 }
1796
1797 // Non-escaping object node should point only to field nodes.
1798 FieldNode* field = j.get()->as_Field();
1799 int offset = field->as_Field()->offset();
1800
1801 // 4. An object is not scalar replaceable if it has a field with unknown
1802 // offset (array's element is accessed in loop).
1803 if (offset == Type::OffsetBot) {
1804 jobj->set_scalar_replaceable(false);
1805 return;
1806 }
1807 // 5. Currently an object is not scalar replaceable if a LoadStore node
1808 // access its field since the field value is unknown after it.
1809 //
1810 Node* n = field->ideal_node();
1811
1812 // Test for an unsafe access that was parsed as maybe off heap
1813 // (with a CheckCastPP to raw memory).
1814 assert(n->is_AddP(), "expect an address computation");
1815 if (n->in(AddPNode::Base)->is_top() &&
1816 n->in(AddPNode::Address)->Opcode() == Op_CheckCastPP) {
1817 assert(n->in(AddPNode::Address)->bottom_type()->isa_rawptr(), "raw address so raw cast expected");
1818 assert(_igvn->type(n->in(AddPNode::Address)->in(1))->isa_oopptr(), "cast pattern at unsafe access expected");
1819 jobj->set_scalar_replaceable(false);
1820 return;
1821 }
1822
1823 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1824 if (n->fast_out(i)->is_LoadStore()) {
1825 jobj->set_scalar_replaceable(false);
1826 return;
1827 }
1828 }
1829
1830 // 6. Or the address may point to more then one object. This may produce
1831 // the false positive result (set not scalar replaceable)
1832 // since the flow-insensitive escape analysis can't separate
1833 // the case when stores overwrite the field's value from the case
1834 // when stores happened on different control branches.
1835 //
1836 // Note: it will disable scalar replacement in some cases:
1837 //
1838 // Point p[] = new Point[1];
1839 // p[0] = new Point(); // Will be not scalar replaced
1840 //
1841 // but it will save us from incorrect optimizations in next cases:
1842 //
1843 // Point p[] = new Point[1];
1844 // if ( x ) p[0] = new Point(); // Will be not scalar replaced
1845 //
1846 if (field->base_count() > 1) {
1847 for (BaseIterator i(field); i.has_next(); i.next()) {
1848 PointsToNode* base = i.get();
1849 // Don't take into account LocalVar nodes which
1850 // may point to only one object which should be also
1851 // this field's base by now.
1852 if (base->is_JavaObject() && base != jobj) {
1853 // Mark all bases.
1854 jobj->set_scalar_replaceable(false);
1855 base->set_scalar_replaceable(false);
1856 }
1857 }
1858 }
1859 }
1860 }
1861
1862 #ifdef ASSERT
1863 void ConnectionGraph::verify_connection_graph(
1864 GrowableArray<PointsToNode*>& ptnodes_worklist,
1865 GrowableArray<JavaObjectNode*>& non_escaped_worklist,
1866 GrowableArray<JavaObjectNode*>& java_objects_worklist,
1867 GrowableArray<Node*>& addp_worklist) {
1868 // Verify that graph is complete - no new edges could be added.
1869 int java_objects_length = java_objects_worklist.length();
1870 int non_escaped_length = non_escaped_worklist.length();
1871 int new_edges = 0;
1872 for (int next = 0; next < java_objects_length; ++next) {
1873 JavaObjectNode* ptn = java_objects_worklist.at(next);
1874 new_edges += add_java_object_edges(ptn, true);
1875 }
1876 assert(new_edges == 0, "graph was not complete");
1877 // Verify that escape state is final.
1878 int length = non_escaped_worklist.length();
1879 find_non_escaped_objects(ptnodes_worklist, non_escaped_worklist);
1880 assert((non_escaped_length == non_escaped_worklist.length()) &&
1881 (non_escaped_length == length) &&
1882 (_worklist.length() == 0), "escape state was not final");
1883
1884 // Verify fields information.
1885 int addp_length = addp_worklist.length();
1886 for (int next = 0; next < addp_length; ++next ) {
1887 Node* n = addp_worklist.at(next);
1888 FieldNode* field = ptnode_adr(n->_idx)->as_Field();
1889 if (field->is_oop()) {
1890 // Verify that field has all bases
1891 Node* base = get_addp_base(n);
1892 PointsToNode* ptn = ptnode_adr(base->_idx);
1893 if (ptn->is_JavaObject()) {
1894 assert(field->has_base(ptn->as_JavaObject()), "sanity");
1895 } else {
1896 assert(ptn->is_LocalVar(), "sanity");
1897 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
1898 PointsToNode* e = i.get();
1899 if (e->is_JavaObject()) {
1900 assert(field->has_base(e->as_JavaObject()), "sanity");
1901 }
1902 }
1903 }
1904 // Verify that all fields have initializing values.
1905 if (field->edge_count() == 0) {
1906 tty->print_cr("----------field does not have references----------");
1907 field->dump();
1908 for (BaseIterator i(field); i.has_next(); i.next()) {
1909 PointsToNode* base = i.get();
1910 tty->print_cr("----------field has next base---------------------");
1911 base->dump();
1912 if (base->is_JavaObject() && (base != phantom_obj) && (base != null_obj)) {
1913 tty->print_cr("----------base has fields-------------------------");
1914 for (EdgeIterator j(base); j.has_next(); j.next()) {
1915 j.get()->dump();
1916 }
1917 tty->print_cr("----------base has references---------------------");
1918 for (UseIterator j(base); j.has_next(); j.next()) {
1919 j.get()->dump();
1920 }
1921 }
1922 }
1923 for (UseIterator i(field); i.has_next(); i.next()) {
1924 i.get()->dump();
1925 }
1926 assert(field->edge_count() > 0, "sanity");
1927 }
1928 }
1929 }
1930 }
1931 #endif
1932
1933 // Optimize ideal graph.
1934 void ConnectionGraph::optimize_ideal_graph(GrowableArray<Node*>& ptr_cmp_worklist,
1935 GrowableArray<Node*>& storestore_worklist) {
1936 Compile* C = _compile;
1937 PhaseIterGVN* igvn = _igvn;
1938 if (EliminateLocks) {
1939 // Mark locks before changing ideal graph.
1940 int cnt = C->macro_count();
1941 for( int i=0; i < cnt; i++ ) {
1942 Node *n = C->macro_node(i);
1943 if (n->is_AbstractLock()) { // Lock and Unlock nodes
1944 AbstractLockNode* alock = n->as_AbstractLock();
1945 if (!alock->is_non_esc_obj()) {
1946 if (not_global_escape(alock->obj_node())) {
1947 assert(!alock->is_eliminated() || alock->is_coarsened(), "sanity");
1948 // The lock could be marked eliminated by lock coarsening
1949 // code during first IGVN before EA. Replace coarsened flag
1950 // to eliminate all associated locks/unlocks.
1951 #ifdef ASSERT
1952 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc3");
1953 #endif
1954 alock->set_non_esc_obj();
1955 }
1956 }
1957 }
1958 }
1959 }
1960
1961 if (OptimizePtrCompare) {
1962 // Add ConI(#CC_GT) and ConI(#CC_EQ).
1963 _pcmp_neq = igvn->makecon(TypeInt::CC_GT);
1964 _pcmp_eq = igvn->makecon(TypeInt::CC_EQ);
1965 // Optimize objects compare.
1966 while (ptr_cmp_worklist.length() != 0) {
1967 Node *n = ptr_cmp_worklist.pop();
1968 Node *res = optimize_ptr_compare(n);
1969 if (res != NULL) {
1970 #ifndef PRODUCT
1971 if (PrintOptimizePtrCompare) {
1972 tty->print_cr("++++ Replaced: %d %s(%d,%d) --> %s", n->_idx, (n->Opcode() == Op_CmpP ? "CmpP" : "CmpN"), n->in(1)->_idx, n->in(2)->_idx, (res == _pcmp_eq ? "EQ" : "NotEQ"));
1973 if (Verbose) {
1974 n->dump(1);
1975 }
1976 }
1977 #endif
1978 igvn->replace_node(n, res);
1979 }
1980 }
1981 // cleanup
1982 if (_pcmp_neq->outcnt() == 0)
1983 igvn->hash_delete(_pcmp_neq);
1984 if (_pcmp_eq->outcnt() == 0)
1985 igvn->hash_delete(_pcmp_eq);
1986 }
1987
1988 // For MemBarStoreStore nodes added in library_call.cpp, check
1989 // escape status of associated AllocateNode and optimize out
1990 // MemBarStoreStore node if the allocated object never escapes.
1991 while (storestore_worklist.length() != 0) {
1992 Node *n = storestore_worklist.pop();
1993 MemBarStoreStoreNode *storestore = n ->as_MemBarStoreStore();
1994 Node *alloc = storestore->in(MemBarNode::Precedent)->in(0);
1995 assert (alloc->is_Allocate(), "storestore should point to AllocateNode");
1996 if (not_global_escape(alloc)) {
1997 MemBarNode* mb = MemBarNode::make(C, Op_MemBarCPUOrder, Compile::AliasIdxBot);
1998 mb->init_req(TypeFunc::Memory, storestore->in(TypeFunc::Memory));
1999 mb->init_req(TypeFunc::Control, storestore->in(TypeFunc::Control));
2000 igvn->register_new_node_with_optimizer(mb);
2001 igvn->replace_node(storestore, mb);
2002 }
2003 }
2004 }
2005
2006 // Optimize objects compare.
2007 Node* ConnectionGraph::optimize_ptr_compare(Node* n) {
2008 assert(OptimizePtrCompare, "sanity");
2009 PointsToNode* ptn1 = ptnode_adr(n->in(1)->_idx);
2010 PointsToNode* ptn2 = ptnode_adr(n->in(2)->_idx);
2011 JavaObjectNode* jobj1 = unique_java_object(n->in(1));
2012 JavaObjectNode* jobj2 = unique_java_object(n->in(2));
2013 assert(ptn1->is_JavaObject() || ptn1->is_LocalVar(), "sanity");
2014 assert(ptn2->is_JavaObject() || ptn2->is_LocalVar(), "sanity");
2015
2016 // Check simple cases first.
2017 if (jobj1 != NULL) {
2018 if (jobj1->escape_state() == PointsToNode::NoEscape) {
2019 if (jobj1 == jobj2) {
2020 // Comparing the same not escaping object.
2021 return _pcmp_eq;
2022 }
2023 Node* obj = jobj1->ideal_node();
2024 // Comparing not escaping allocation.
2025 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
2026 !ptn2->points_to(jobj1)) {
2027 return _pcmp_neq; // This includes nullness check.
2028 }
2029 }
2030 }
2031 if (jobj2 != NULL) {
2032 if (jobj2->escape_state() == PointsToNode::NoEscape) {
2033 Node* obj = jobj2->ideal_node();
2034 // Comparing not escaping allocation.
2035 if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
2036 !ptn1->points_to(jobj2)) {
2037 return _pcmp_neq; // This includes nullness check.
2038 }
2039 }
2040 }
2041 if (jobj1 != NULL && jobj1 != phantom_obj &&
2042 jobj2 != NULL && jobj2 != phantom_obj &&
2043 jobj1->ideal_node()->is_Con() &&
2044 jobj2->ideal_node()->is_Con()) {
2045 // Klass or String constants compare. Need to be careful with
2046 // compressed pointers - compare types of ConN and ConP instead of nodes.
2047 const Type* t1 = jobj1->ideal_node()->get_ptr_type();
2048 const Type* t2 = jobj2->ideal_node()->get_ptr_type();
2049 if (t1->make_ptr() == t2->make_ptr()) {
2050 return _pcmp_eq;
2051 } else {
2052 return _pcmp_neq;
2053 }
2054 }
2055 if (ptn1->meet(ptn2)) {
2056 return NULL; // Sets are not disjoint
2057 }
2058
2059 // Sets are disjoint.
2060 bool set1_has_unknown_ptr = ptn1->points_to(phantom_obj);
2061 bool set2_has_unknown_ptr = ptn2->points_to(phantom_obj);
2062 bool set1_has_null_ptr = ptn1->points_to(null_obj);
2063 bool set2_has_null_ptr = ptn2->points_to(null_obj);
2064 if ((set1_has_unknown_ptr && set2_has_null_ptr) ||
2065 (set2_has_unknown_ptr && set1_has_null_ptr)) {
2066 // Check nullness of unknown object.
2067 return NULL;
2068 }
2069
2070 // Disjointness by itself is not sufficient since
2071 // alias analysis is not complete for escaped objects.
2072 // Disjoint sets are definitely unrelated only when
2073 // at least one set has only not escaping allocations.
2074 if (!set1_has_unknown_ptr && !set1_has_null_ptr) {
2075 if (ptn1->non_escaping_allocation()) {
2076 return _pcmp_neq;
2077 }
2078 }
2079 if (!set2_has_unknown_ptr && !set2_has_null_ptr) {
2080 if (ptn2->non_escaping_allocation()) {
2081 return _pcmp_neq;
2082 }
2083 }
2084 return NULL;
2085 }
2086
2087 // Connection Graph constuction functions.
2088
2089 void ConnectionGraph::add_local_var(Node *n, PointsToNode::EscapeState es) {
2090 PointsToNode* ptadr = _nodes.at(n->_idx);
2091 if (ptadr != NULL) {
2092 assert(ptadr->is_LocalVar() && ptadr->ideal_node() == n, "sanity");
2093 return;
2094 }
2095 Compile* C = _compile;
2096 ptadr = new (C->comp_arena()) LocalVarNode(this, n, es);
2097 _nodes.at_put(n->_idx, ptadr);
2098 }
2099
2100 void ConnectionGraph::add_java_object(Node *n, PointsToNode::EscapeState es) {
2101 PointsToNode* ptadr = _nodes.at(n->_idx);
2102 if (ptadr != NULL) {
2103 assert(ptadr->is_JavaObject() && ptadr->ideal_node() == n, "sanity");
2104 return;
2105 }
2106 Compile* C = _compile;
2107 ptadr = new (C->comp_arena()) JavaObjectNode(this, n, es);
2108 _nodes.at_put(n->_idx, ptadr);
2109 }
2110
2111 void ConnectionGraph::add_field(Node *n, PointsToNode::EscapeState es, int offset) {
2112 PointsToNode* ptadr = _nodes.at(n->_idx);
2113 if (ptadr != NULL) {
2114 assert(ptadr->is_Field() && ptadr->ideal_node() == n, "sanity");
2115 return;
2116 }
2117 bool unsafe = false;
2118 bool is_oop = is_oop_field(n, offset, &unsafe);
2119 if (unsafe) {
2120 es = PointsToNode::GlobalEscape;
2121 }
2122 Compile* C = _compile;
2123 FieldNode* field = new (C->comp_arena()) FieldNode(this, n, es, offset, is_oop);
2124 _nodes.at_put(n->_idx, field);
2125 }
2126
2127 void ConnectionGraph::add_arraycopy(Node *n, PointsToNode::EscapeState es,
2128 PointsToNode* src, PointsToNode* dst) {
2129 assert(!src->is_Field() && !dst->is_Field(), "only for JavaObject and LocalVar");
2130 assert((src != null_obj) && (dst != null_obj), "not for ConP NULL");
2131 PointsToNode* ptadr = _nodes.at(n->_idx);
2132 if (ptadr != NULL) {
2133 assert(ptadr->is_Arraycopy() && ptadr->ideal_node() == n, "sanity");
2134 return;
2135 }
2136 Compile* C = _compile;
2137 ptadr = new (C->comp_arena()) ArraycopyNode(this, n, es);
2138 _nodes.at_put(n->_idx, ptadr);
2139 // Add edge from arraycopy node to source object.
2140 (void)add_edge(ptadr, src);
2141 src->set_arraycopy_src();
2142 // Add edge from destination object to arraycopy node.
2143 (void)add_edge(dst, ptadr);
2144 dst->set_arraycopy_dst();
2145 }
2146
2147 bool ConnectionGraph::is_oop_field(Node* n, int offset, bool* unsafe) {
2148 const Type* adr_type = n->as_AddP()->bottom_type();
2149 BasicType bt = T_INT;
2150 if (offset == Type::OffsetBot) {
2151 // Check only oop fields.
2152 if (!adr_type->isa_aryptr() ||
2153 (adr_type->isa_aryptr()->klass() == NULL) ||
2154 adr_type->isa_aryptr()->klass()->is_obj_array_klass()) {
2155 // OffsetBot is used to reference array's element. Ignore first AddP.
2156 if (find_second_addp(n, n->in(AddPNode::Base)) == NULL) {
2157 bt = T_OBJECT;
2158 }
2159 }
2160 } else if (offset != oopDesc::klass_offset_in_bytes()) {
2161 if (adr_type->isa_instptr()) {
2162 ciField* field = _compile->alias_type(adr_type->isa_instptr())->field();
2163 if (field != NULL) {
2164 bt = field->layout_type();
2165 } else {
2166 // Check for unsafe oop field access
2167 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2168 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2169 #if INCLUDE_SHENANDOAHGC
2170 n->has_out_with(Op_ShenandoahCompareAndExchangeP) || n->has_out_with(Op_ShenandoahCompareAndExchangeN) ||
2171 n->has_out_with(Op_ShenandoahCompareAndSwapP, Op_ShenandoahCompareAndSwapN, Op_ShenandoahWeakCompareAndSwapP, Op_ShenandoahWeakCompareAndSwapN) ||
2172 #endif
2173 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) {
2174 bt = T_OBJECT;
2175 (*unsafe) = true;
2176 }
2177 }
2178 } else if (adr_type->isa_aryptr()) {
2179 if (offset == arrayOopDesc::length_offset_in_bytes()) {
2180 // Ignore array length load.
2181 } else if (find_second_addp(n, n->in(AddPNode::Base)) != NULL) {
2182 // Ignore first AddP.
2183 } else {
2184 const Type* elemtype = adr_type->isa_aryptr()->elem();
2185 bt = elemtype->array_element_basic_type();
2186 }
2187 } else if (adr_type->isa_rawptr() || adr_type->isa_klassptr()) {
2188 // Allocation initialization, ThreadLocal field access, unsafe access
2189 if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
2190 n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
2191 n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) {
2192 bt = T_OBJECT;
2193 }
2194 }
2195 }
2196 return (bt == T_OBJECT || bt == T_NARROWOOP || bt == T_ARRAY);
2197 }
2198
2199 // Returns unique pointed java object or NULL.
2200 JavaObjectNode* ConnectionGraph::unique_java_object(Node *n) {
2201 assert(!_collecting, "should not call when contructed graph");
2202 // If the node was created after the escape computation we can't answer.
2203 uint idx = n->_idx;
2204 if (idx >= nodes_size()) {
2205 return NULL;
2206 }
2207 PointsToNode* ptn = ptnode_adr(idx);
2208 if (ptn->is_JavaObject()) {
2209 return ptn->as_JavaObject();
2210 }
2211 assert(ptn->is_LocalVar(), "sanity");
2212 // Check all java objects it points to.
2213 JavaObjectNode* jobj = NULL;
2214 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2215 PointsToNode* e = i.get();
2216 if (e->is_JavaObject()) {
2217 if (jobj == NULL) {
2218 jobj = e->as_JavaObject();
2219 } else if (jobj != e) {
2220 return NULL;
2221 }
2222 }
2223 }
2224 return jobj;
2225 }
2226
2227 // Return true if this node points only to non-escaping allocations.
2228 bool PointsToNode::non_escaping_allocation() {
2229 if (is_JavaObject()) {
2230 Node* n = ideal_node();
2231 if (n->is_Allocate() || n->is_CallStaticJava()) {
2232 return (escape_state() == PointsToNode::NoEscape);
2233 } else {
2234 return false;
2235 }
2236 }
2237 assert(is_LocalVar(), "sanity");
2238 // Check all java objects it points to.
2239 for (EdgeIterator i(this); i.has_next(); i.next()) {
2240 PointsToNode* e = i.get();
2241 if (e->is_JavaObject()) {
2242 Node* n = e->ideal_node();
2243 if ((e->escape_state() != PointsToNode::NoEscape) ||
2244 !(n->is_Allocate() || n->is_CallStaticJava())) {
2245 return false;
2246 }
2247 }
2248 }
2249 return true;
2250 }
2251
2252 // Return true if we know the node does not escape globally.
2253 bool ConnectionGraph::not_global_escape(Node *n) {
2254 assert(!_collecting, "should not call during graph construction");
2255 // If the node was created after the escape computation we can't answer.
2256 uint idx = n->_idx;
2257 if (idx >= nodes_size()) {
2258 return false;
2259 }
2260 PointsToNode* ptn = ptnode_adr(idx);
2261 PointsToNode::EscapeState es = ptn->escape_state();
2262 // If we have already computed a value, return it.
2263 if (es >= PointsToNode::GlobalEscape)
2264 return false;
2265 if (ptn->is_JavaObject()) {
2266 return true; // (es < PointsToNode::GlobalEscape);
2267 }
2268 assert(ptn->is_LocalVar(), "sanity");
2269 // Check all java objects it points to.
2270 for (EdgeIterator i(ptn); i.has_next(); i.next()) {
2271 if (i.get()->escape_state() >= PointsToNode::GlobalEscape)
2272 return false;
2273 }
2274 return true;
2275 }
2276
2277
2278 // Helper functions
2279
2280 // Return true if this node points to specified node or nodes it points to.
2281 bool PointsToNode::points_to(JavaObjectNode* ptn) const {
2282 if (is_JavaObject()) {
2283 return (this == ptn);
2284 }
2285 assert(is_LocalVar() || is_Field(), "sanity");
2286 for (EdgeIterator i(this); i.has_next(); i.next()) {
2287 if (i.get() == ptn)
2288 return true;
2289 }
2290 return false;
2291 }
2292
2293 // Return true if one node points to an other.
2294 bool PointsToNode::meet(PointsToNode* ptn) {
2295 if (this == ptn) {
2296 return true;
2297 } else if (ptn->is_JavaObject()) {
2298 return this->points_to(ptn->as_JavaObject());
2299 } else if (this->is_JavaObject()) {
2300 return ptn->points_to(this->as_JavaObject());
2301 }
2302 assert(this->is_LocalVar() && ptn->is_LocalVar(), "sanity");
2303 int ptn_count = ptn->edge_count();
2304 for (EdgeIterator i(this); i.has_next(); i.next()) {
2305 PointsToNode* this_e = i.get();
2306 for (int j = 0; j < ptn_count; j++) {
2307 if (this_e == ptn->edge(j))
2308 return true;
2309 }
2310 }
2311 return false;
2312 }
2313
2314 #ifdef ASSERT
2315 // Return true if bases point to this java object.
2316 bool FieldNode::has_base(JavaObjectNode* jobj) const {
2317 for (BaseIterator i(this); i.has_next(); i.next()) {
2318 if (i.get() == jobj)
2319 return true;
2320 }
2321 return false;
2322 }
2323 #endif
2324
2325 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
2326 const Type *adr_type = phase->type(adr);
2327 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL &&
2328 adr->in(AddPNode::Address)->is_Proj() &&
2329 adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
2330 // We are computing a raw address for a store captured by an Initialize
2331 // compute an appropriate address type. AddP cases #3 and #5 (see below).
2332 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
2333 assert(offs != Type::OffsetBot ||
2334 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
2335 "offset must be a constant or it is initialization of array");
2336 return offs;
2337 }
2338 const TypePtr *t_ptr = adr_type->isa_ptr();
2339 assert(t_ptr != NULL, "must be a pointer type");
2340 return t_ptr->offset();
2341 }
2342
2343 Node* ConnectionGraph::get_addp_base(Node *addp) {
2344 assert(addp->is_AddP(), "must be AddP");
2345 //
2346 // AddP cases for Base and Address inputs:
2347 // case #1. Direct object's field reference:
2348 // Allocate
2349 // |
2350 // Proj #5 ( oop result )
2351 // |
2352 // CheckCastPP (cast to instance type)
2353 // | |
2354 // AddP ( base == address )
2355 //
2356 // case #2. Indirect object's field reference:
2357 // Phi
2358 // |
2359 // CastPP (cast to instance type)
2360 // | |
2361 // AddP ( base == address )
2362 //
2363 // case #3. Raw object's field reference for Initialize node:
2364 // Allocate
2365 // |
2366 // Proj #5 ( oop result )
2367 // top |
2368 // \ |
2369 // AddP ( base == top )
2370 //
2371 // case #4. Array's element reference:
2372 // {CheckCastPP | CastPP}
2373 // | | |
2374 // | AddP ( array's element offset )
2375 // | |
2376 // AddP ( array's offset )
2377 //
2378 // case #5. Raw object's field reference for arraycopy stub call:
2379 // The inline_native_clone() case when the arraycopy stub is called
2380 // after the allocation before Initialize and CheckCastPP nodes.
2381 // Allocate
2382 // |
2383 // Proj #5 ( oop result )
2384 // | |
2385 // AddP ( base == address )
2386 //
2387 // case #6. Constant Pool, ThreadLocal, CastX2P or
2388 // Raw object's field reference:
2389 // {ConP, ThreadLocal, CastX2P, raw Load}
2390 // top |
2391 // \ |
2392 // AddP ( base == top )
2393 //
2394 // case #7. Klass's field reference.
2395 // LoadKlass
2396 // | |
2397 // AddP ( base == address )
2398 //
2399 // case #8. narrow Klass's field reference.
2400 // LoadNKlass
2401 // |
2402 // DecodeN
2403 // | |
2404 // AddP ( base == address )
2405 //
2406 // case #9. Mixed unsafe access
2407 // {instance}
2408 // |
2409 // CheckCastPP (raw)
2410 // top |
2411 // \ |
2412 // AddP ( base == top )
2413 //
2414 Node *base = addp->in(AddPNode::Base);
2415 if (base->uncast()->is_top()) { // The AddP case #3 and #6 and #9.
2416 base = addp->in(AddPNode::Address);
2417 while (base->is_AddP()) {
2418 // Case #6 (unsafe access) may have several chained AddP nodes.
2419 assert(base->in(AddPNode::Base)->uncast()->is_top(), "expected unsafe access address only");
2420 base = base->in(AddPNode::Address);
2421 }
2422 if (base->Opcode() == Op_CheckCastPP &&
2423 base->bottom_type()->isa_rawptr() &&
2424 _igvn->type(base->in(1))->isa_oopptr()) {
2425 base = base->in(1); // Case #9
2426 } else {
2427 Node* uncast_base = base->uncast();
2428 int opcode = uncast_base->Opcode();
2429 assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
2430 opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
2431 (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) ||
2432 (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()) ||
2433 uncast_base->is_ShenandoahBarrier(), "sanity");
2434 }
2435 }
2436 return base;
2437 }
2438
2439 Node* ConnectionGraph::find_second_addp(Node* addp, Node* n) {
2440 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
2441 Node* addp2 = addp->raw_out(0);
2442 if (addp->outcnt() == 1 && addp2->is_AddP() &&
2443 addp2->in(AddPNode::Base) == n &&
2444 addp2->in(AddPNode::Address) == addp) {
2445 assert(addp->in(AddPNode::Base) == n, "expecting the same base");
2446 //
2447 // Find array's offset to push it on worklist first and
2448 // as result process an array's element offset first (pushed second)
2449 // to avoid CastPP for the array's offset.
2450 // Otherwise the inserted CastPP (LocalVar) will point to what
2451 // the AddP (Field) points to. Which would be wrong since
2452 // the algorithm expects the CastPP has the same point as
2453 // as AddP's base CheckCastPP (LocalVar).
2454 //
2455 // ArrayAllocation
2456 // |
2457 // CheckCastPP
2458 // |
2459 // memProj (from ArrayAllocation CheckCastPP)
2460 // | ||
2461 // | || Int (element index)
2462 // | || | ConI (log(element size))
2463 // | || | /
2464 // | || LShift
2465 // | || /
2466 // | AddP (array's element offset)
2467 // | |
2468 // | | ConI (array's offset: #12(32-bits) or #24(64-bits))
2469 // | / /
2470 // AddP (array's offset)
2471 // |
2472 // Load/Store (memory operation on array's element)
2473 //
2474 return addp2;
2475 }
2476 return NULL;
2477 }
2478
2479 //
2480 // Adjust the type and inputs of an AddP which computes the
2481 // address of a field of an instance
2482 //
2483 bool ConnectionGraph::split_AddP(Node *addp, Node *base) {
2484 PhaseGVN* igvn = _igvn;
2485 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
2486 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
2487 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
2488 if (t == NULL) {
2489 // We are computing a raw address for a store captured by an Initialize
2490 // compute an appropriate address type (cases #3 and #5).
2491 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
2492 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
2493 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
2494 assert(offs != Type::OffsetBot, "offset must be a constant");
2495 t = base_t->add_offset(offs)->is_oopptr();
2496 }
2497 int inst_id = base_t->instance_id();
2498 assert(!t->is_known_instance() || t->instance_id() == inst_id,
2499 "old type must be non-instance or match new type");
2500
2501 // The type 't' could be subclass of 'base_t'.
2502 // As result t->offset() could be large then base_t's size and it will
2503 // cause the failure in add_offset() with narrow oops since TypeOopPtr()
2504 // constructor verifies correctness of the offset.
2505 //
2506 // It could happened on subclass's branch (from the type profiling
2507 // inlining) which was not eliminated during parsing since the exactness
2508 // of the allocation type was not propagated to the subclass type check.
2509 //
2510 // Or the type 't' could be not related to 'base_t' at all.
2511 // It could happened when CHA type is different from MDO type on a dead path
2512 // (for example, from instanceof check) which is not collapsed during parsing.
2513 //
2514 // Do nothing for such AddP node and don't process its users since
2515 // this code branch will go away.
2516 //
2517 if (!t->is_known_instance() &&
2518 !base_t->klass()->is_subtype_of(t->klass())) {
2519 return false; // bail out
2520 }
2521 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
2522 // Do NOT remove the next line: ensure a new alias index is allocated
2523 // for the instance type. Note: C++ will not remove it since the call
2524 // has side effect.
2525 int alias_idx = _compile->get_alias_index(tinst);
2526 igvn->set_type(addp, tinst);
2527 // record the allocation in the node map
2528 set_map(addp, get_map(base->_idx));
2529 // Set addp's Base and Address to 'base'.
2530 Node *abase = addp->in(AddPNode::Base);
2531 Node *adr = addp->in(AddPNode::Address);
2532 if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
2533 adr->in(0)->_idx == (uint)inst_id) {
2534 // Skip AddP cases #3 and #5.
2535 } else {
2536 assert(!abase->is_top(), "sanity"); // AddP case #3
2537 if (abase != base) {
2538 igvn->hash_delete(addp);
2539 addp->set_req(AddPNode::Base, base);
2540 if (abase == adr) {
2541 addp->set_req(AddPNode::Address, base);
2542 } else {
2543 // AddP case #4 (adr is array's element offset AddP node)
2544 #ifdef ASSERT
2545 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
2546 assert(adr->is_AddP() && atype != NULL &&
2547 atype->instance_id() == inst_id, "array's element offset should be processed first");
2548 #endif
2549 }
2550 igvn->hash_insert(addp);
2551 }
2552 }
2553 // Put on IGVN worklist since at least addp's type was changed above.
2554 record_for_optimizer(addp);
2555 return true;
2556 }
2557
2558 //
2559 // Create a new version of orig_phi if necessary. Returns either the newly
2560 // created phi or an existing phi. Sets create_new to indicate whether a new
2561 // phi was created. Cache the last newly created phi in the node map.
2562 //
2563 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, bool &new_created) {
2564 Compile *C = _compile;
2565 PhaseGVN* igvn = _igvn;
2566 new_created = false;
2567 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
2568 // nothing to do if orig_phi is bottom memory or matches alias_idx
2569 if (phi_alias_idx == alias_idx) {
2570 return orig_phi;
2571 }
2572 // Have we recently created a Phi for this alias index?
2573 PhiNode *result = get_map_phi(orig_phi->_idx);
2574 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
2575 return result;
2576 }
2577 // Previous check may fail when the same wide memory Phi was split into Phis
2578 // for different memory slices. Search all Phis for this region.
2579 if (result != NULL) {
2580 Node* region = orig_phi->in(0);
2581 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
2582 Node* phi = region->fast_out(i);
2583 if (phi->is_Phi() &&
2584 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
2585 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
2586 return phi->as_Phi();
2587 }
2588 }
2589 }
2590 if (C->live_nodes() + 2*NodeLimitFudgeFactor > C->max_node_limit()) {
2591 if (C->do_escape_analysis() == true && !C->failing()) {
2592 // Retry compilation without escape analysis.
2593 // If this is the first failure, the sentinel string will "stick"
2594 // to the Compile object, and the C2Compiler will see it and retry.
2595 C->record_failure(C2Compiler::retry_no_escape_analysis());
2596 }
2597 return NULL;
2598 }
2599 orig_phi_worklist.append_if_missing(orig_phi);
2600 const TypePtr *atype = C->get_adr_type(alias_idx);
2601 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
2602 C->copy_node_notes_to(result, orig_phi);
2603 igvn->set_type(result, result->bottom_type());
2604 record_for_optimizer(result);
2605 set_map(orig_phi, result);
2606 new_created = true;
2607 return result;
2608 }
2609
2610 //
2611 // Return a new version of Memory Phi "orig_phi" with the inputs having the
2612 // specified alias index.
2613 //
2614 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist) {
2615 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
2616 Compile *C = _compile;
2617 PhaseGVN* igvn = _igvn;
2618 bool new_phi_created;
2619 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, new_phi_created);
2620 if (!new_phi_created) {
2621 return result;
2622 }
2623 GrowableArray<PhiNode *> phi_list;
2624 GrowableArray<uint> cur_input;
2625 PhiNode *phi = orig_phi;
2626 uint idx = 1;
2627 bool finished = false;
2628 while(!finished) {
2629 while (idx < phi->req()) {
2630 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist);
2631 if (mem != NULL && mem->is_Phi()) {
2632 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, new_phi_created);
2633 if (new_phi_created) {
2634 // found an phi for which we created a new split, push current one on worklist and begin
2635 // processing new one
2636 phi_list.push(phi);
2637 cur_input.push(idx);
2638 phi = mem->as_Phi();
2639 result = newphi;
2640 idx = 1;
2641 continue;
2642 } else {
2643 mem = newphi;
2644 }
2645 }
2646 if (C->failing()) {
2647 return NULL;
2648 }
2649 result->set_req(idx++, mem);
2650 }
2651 #ifdef ASSERT
2652 // verify that the new Phi has an input for each input of the original
2653 assert( phi->req() == result->req(), "must have same number of inputs.");
2654 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
2655 #endif
2656 // Check if all new phi's inputs have specified alias index.
2657 // Otherwise use old phi.
2658 for (uint i = 1; i < phi->req(); i++) {
2659 Node* in = result->in(i);
2660 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
2661 }
2662 // we have finished processing a Phi, see if there are any more to do
2663 finished = (phi_list.length() == 0 );
2664 if (!finished) {
2665 phi = phi_list.pop();
2666 idx = cur_input.pop();
2667 PhiNode *prev_result = get_map_phi(phi->_idx);
2668 prev_result->set_req(idx++, result);
2669 result = prev_result;
2670 }
2671 }
2672 return result;
2673 }
2674
2675 //
2676 // The next methods are derived from methods in MemNode.
2677 //
2678 Node* ConnectionGraph::step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
2679 Node *mem = mmem;
2680 // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
2681 // means an array I have not precisely typed yet. Do not do any
2682 // alias stuff with it any time soon.
2683 if (toop->base() != Type::AnyPtr &&
2684 !(toop->klass() != NULL &&
2685 toop->klass()->is_java_lang_Object() &&
2686 toop->offset() == Type::OffsetBot)) {
2687 mem = mmem->memory_at(alias_idx);
2688 // Update input if it is progress over what we have now
2689 }
2690 return mem;
2691 }
2692
2693 //
2694 // Move memory users to their memory slices.
2695 //
2696 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *> &orig_phis) {
2697 Compile* C = _compile;
2698 PhaseGVN* igvn = _igvn;
2699 const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
2700 assert(tp != NULL, "ptr type");
2701 int alias_idx = C->get_alias_index(tp);
2702 int general_idx = C->get_general_index(alias_idx);
2703
2704 // Move users first
2705 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2706 Node* use = n->fast_out(i);
2707 if (use->is_MergeMem()) {
2708 MergeMemNode* mmem = use->as_MergeMem();
2709 assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
2710 if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
2711 continue; // Nothing to do
2712 }
2713 // Replace previous general reference to mem node.
2714 uint orig_uniq = C->unique();
2715 Node* m = find_inst_mem(n, general_idx, orig_phis);
2716 assert(orig_uniq == C->unique(), "no new nodes");
2717 mmem->set_memory_at(general_idx, m);
2718 --imax;
2719 --i;
2720 } else if (use->is_MemBar()) {
2721 assert(!use->is_Initialize(), "initializing stores should not be moved");
2722 if (use->req() > MemBarNode::Precedent &&
2723 use->in(MemBarNode::Precedent) == n) {
2724 // Don't move related membars.
2725 record_for_optimizer(use);
2726 continue;
2727 }
2728 tp = use->as_MemBar()->adr_type()->isa_ptr();
2729 if ((tp != NULL && C->get_alias_index(tp) == alias_idx) ||
2730 alias_idx == general_idx) {
2731 continue; // Nothing to do
2732 }
2733 // Move to general memory slice.
2734 uint orig_uniq = C->unique();
2735 Node* m = find_inst_mem(n, general_idx, orig_phis);
2736 assert(orig_uniq == C->unique(), "no new nodes");
2737 igvn->hash_delete(use);
2738 imax -= use->replace_edge(n, m);
2739 igvn->hash_insert(use);
2740 record_for_optimizer(use);
2741 --i;
2742 #ifdef ASSERT
2743 } else if (use->is_Mem()) {
2744 if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) {
2745 // Don't move related cardmark.
2746 continue;
2747 }
2748 // Memory nodes should have new memory input.
2749 tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
2750 assert(tp != NULL, "ptr type");
2751 int idx = C->get_alias_index(tp);
2752 assert(get_map(use->_idx) != NULL || idx == alias_idx,
2753 "Following memory nodes should have new memory input or be on the same memory slice");
2754 } else if (use->is_Phi()) {
2755 // Phi nodes should be split and moved already.
2756 tp = use->as_Phi()->adr_type()->isa_ptr();
2757 assert(tp != NULL, "ptr type");
2758 int idx = C->get_alias_index(tp);
2759 assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
2760 } else {
2761 use->dump();
2762 assert(false, "should not be here");
2763 #endif
2764 }
2765 }
2766 }
2767
2768 //
2769 // Search memory chain of "mem" to find a MemNode whose address
2770 // is the specified alias index.
2771 //
2772 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis) {
2773 if (orig_mem == NULL)
2774 return orig_mem;
2775 Compile* C = _compile;
2776 PhaseGVN* igvn = _igvn;
2777 const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
2778 bool is_instance = (toop != NULL) && toop->is_known_instance();
2779 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
2780 Node *prev = NULL;
2781 Node *result = orig_mem;
2782 while (prev != result) {
2783 prev = result;
2784 if (result == start_mem)
2785 break; // hit one of our sentinels
2786 if (result->is_Mem()) {
2787 const Type *at = igvn->type(result->in(MemNode::Address));
2788 if (at == Type::TOP)
2789 break; // Dead
2790 assert (at->isa_ptr() != NULL, "pointer type required.");
2791 int idx = C->get_alias_index(at->is_ptr());
2792 if (idx == alias_idx)
2793 break; // Found
2794 if (!is_instance && (at->isa_oopptr() == NULL ||
2795 !at->is_oopptr()->is_known_instance())) {
2796 break; // Do not skip store to general memory slice.
2797 }
2798 result = result->in(MemNode::Memory);
2799 }
2800 if (!is_instance)
2801 continue; // don't search further for non-instance types
2802 // skip over a call which does not affect this memory slice
2803 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
2804 Node *proj_in = result->in(0);
2805 if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
2806 break; // hit one of our sentinels
2807 } else if (proj_in->is_Call()) {
2808 // ArrayCopy node processed here as well
2809 CallNode *call = proj_in->as_Call();
2810 if (!call->may_modify(toop, igvn)) {
2811 result = call->in(TypeFunc::Memory);
2812 }
2813 } else if (proj_in->is_Initialize()) {
2814 AllocateNode* alloc = proj_in->as_Initialize()->allocation();
2815 // Stop if this is the initialization for the object instance which
2816 // which contains this memory slice, otherwise skip over it.
2817 if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) {
2818 result = proj_in->in(TypeFunc::Memory);
2819 }
2820 } else if (proj_in->is_MemBar()) {
2821 if (proj_in->in(TypeFunc::Memory)->is_MergeMem() &&
2822 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->is_Proj() &&
2823 proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->is_ArrayCopy()) {
2824 // clone
2825 ArrayCopyNode* ac = proj_in->in(TypeFunc::Memory)->as_MergeMem()->in(Compile::AliasIdxRaw)->in(0)->as_ArrayCopy();
2826 if (ac->may_modify(toop, igvn)) {
2827 break;
2828 }
2829 }
2830 result = proj_in->in(TypeFunc::Memory);
2831 }
2832 } else if (result->is_MergeMem()) {
2833 MergeMemNode *mmem = result->as_MergeMem();
2834 result = step_through_mergemem(mmem, alias_idx, toop);
2835 if (result == mmem->base_memory()) {
2836 // Didn't find instance memory, search through general slice recursively.
2837 result = mmem->memory_at(C->get_general_index(alias_idx));
2838 result = find_inst_mem(result, alias_idx, orig_phis);
2839 if (C->failing()) {
2840 return NULL;
2841 }
2842 mmem->set_memory_at(alias_idx, result);
2843 }
2844 } else if (result->is_Phi() &&
2845 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
2846 Node *un = result->as_Phi()->unique_input(igvn);
2847 if (un != NULL) {
2848 orig_phis.append_if_missing(result->as_Phi());
2849 result = un;
2850 } else {
2851 break;
2852 }
2853 } else if (result->is_ClearArray()) {
2854 if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), igvn)) {
2855 // Can not bypass initialization of the instance
2856 // we are looking for.
2857 break;
2858 }
2859 // Otherwise skip it (the call updated 'result' value).
2860 } else if (result->Opcode() == Op_SCMemProj) {
2861 Node* mem = result->in(0);
2862 Node* adr = NULL;
2863 if (mem->is_LoadStore()) {
2864 adr = mem->in(MemNode::Address);
2865 } else {
2866 assert(mem->Opcode() == Op_EncodeISOArray ||
2867 mem->Opcode() == Op_StrCompressedCopy, "sanity");
2868 adr = mem->in(3); // Memory edge corresponds to destination array
2869 }
2870 const Type *at = igvn->type(adr);
2871 if (at != Type::TOP) {
2872 assert(at->isa_ptr() != NULL, "pointer type required.");
2873 int idx = C->get_alias_index(at->is_ptr());
2874 if (idx == alias_idx) {
2875 // Assert in debug mode
2876 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
2877 break; // In product mode return SCMemProj node
2878 }
2879 }
2880 result = mem->in(MemNode::Memory);
2881 } else if (result->Opcode() == Op_StrInflatedCopy) {
2882 Node* adr = result->in(3); // Memory edge corresponds to destination array
2883 const Type *at = igvn->type(adr);
2884 if (at != Type::TOP) {
2885 assert(at->isa_ptr() != NULL, "pointer type required.");
2886 int idx = C->get_alias_index(at->is_ptr());
2887 if (idx == alias_idx) {
2888 // Assert in debug mode
2889 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
2890 break; // In product mode return SCMemProj node
2891 }
2892 }
2893 result = result->in(MemNode::Memory);
2894 }
2895 }
2896 if (result->is_Phi()) {
2897 PhiNode *mphi = result->as_Phi();
2898 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
2899 const TypePtr *t = mphi->adr_type();
2900 if (!is_instance) {
2901 // Push all non-instance Phis on the orig_phis worklist to update inputs
2902 // during Phase 4 if needed.
2903 orig_phis.append_if_missing(mphi);
2904 } else if (C->get_alias_index(t) != alias_idx) {
2905 // Create a new Phi with the specified alias index type.
2906 result = split_memory_phi(mphi, alias_idx, orig_phis);
2907 }
2908 }
2909 // the result is either MemNode, PhiNode, InitializeNode.
2910 return result;
2911 }
2912
2913 //
2914 // Convert the types of unescaped object to instance types where possible,
2915 // propagate the new type information through the graph, and update memory
2916 // edges and MergeMem inputs to reflect the new type.
2917 //
2918 // We start with allocations (and calls which may be allocations) on alloc_worklist.
2919 // The processing is done in 4 phases:
2920 //
2921 // Phase 1: Process possible allocations from alloc_worklist. Create instance
2922 // types for the CheckCastPP for allocations where possible.
2923 // Propagate the new types through users as follows:
2924 // casts and Phi: push users on alloc_worklist
2925 // AddP: cast Base and Address inputs to the instance type
2926 // push any AddP users on alloc_worklist and push any memnode
2927 // users onto memnode_worklist.
2928 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
2929 // search the Memory chain for a store with the appropriate type
2930 // address type. If a Phi is found, create a new version with
2931 // the appropriate memory slices from each of the Phi inputs.
2932 // For stores, process the users as follows:
2933 // MemNode: push on memnode_worklist
2934 // MergeMem: push on mergemem_worklist
2935 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
2936 // moving the first node encountered of each instance type to the
2937 // the input corresponding to its alias index.
2938 // appropriate memory slice.
2939 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
2940 //
2941 // In the following example, the CheckCastPP nodes are the cast of allocation
2942 // results and the allocation of node 29 is unescaped and eligible to be an
2943 // instance type.
2944 //
2945 // We start with:
2946 //
2947 // 7 Parm #memory
2948 // 10 ConI "12"
2949 // 19 CheckCastPP "Foo"
2950 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2951 // 29 CheckCastPP "Foo"
2952 // 30 AddP _ 29 29 10 Foo+12 alias_index=4
2953 //
2954 // 40 StoreP 25 7 20 ... alias_index=4
2955 // 50 StoreP 35 40 30 ... alias_index=4
2956 // 60 StoreP 45 50 20 ... alias_index=4
2957 // 70 LoadP _ 60 30 ... alias_index=4
2958 // 80 Phi 75 50 60 Memory alias_index=4
2959 // 90 LoadP _ 80 30 ... alias_index=4
2960 // 100 LoadP _ 80 20 ... alias_index=4
2961 //
2962 //
2963 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
2964 // and creating a new alias index for node 30. This gives:
2965 //
2966 // 7 Parm #memory
2967 // 10 ConI "12"
2968 // 19 CheckCastPP "Foo"
2969 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2970 // 29 CheckCastPP "Foo" iid=24
2971 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
2972 //
2973 // 40 StoreP 25 7 20 ... alias_index=4
2974 // 50 StoreP 35 40 30 ... alias_index=6
2975 // 60 StoreP 45 50 20 ... alias_index=4
2976 // 70 LoadP _ 60 30 ... alias_index=6
2977 // 80 Phi 75 50 60 Memory alias_index=4
2978 // 90 LoadP _ 80 30 ... alias_index=6
2979 // 100 LoadP _ 80 20 ... alias_index=4
2980 //
2981 // In phase 2, new memory inputs are computed for the loads and stores,
2982 // And a new version of the phi is created. In phase 4, the inputs to
2983 // node 80 are updated and then the memory nodes are updated with the
2984 // values computed in phase 2. This results in:
2985 //
2986 // 7 Parm #memory
2987 // 10 ConI "12"
2988 // 19 CheckCastPP "Foo"
2989 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
2990 // 29 CheckCastPP "Foo" iid=24
2991 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
2992 //
2993 // 40 StoreP 25 7 20 ... alias_index=4
2994 // 50 StoreP 35 7 30 ... alias_index=6
2995 // 60 StoreP 45 40 20 ... alias_index=4
2996 // 70 LoadP _ 50 30 ... alias_index=6
2997 // 80 Phi 75 40 60 Memory alias_index=4
2998 // 120 Phi 75 50 50 Memory alias_index=6
2999 // 90 LoadP _ 120 30 ... alias_index=6
3000 // 100 LoadP _ 80 20 ... alias_index=4
3001 //
3002 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist, GrowableArray<ArrayCopyNode*> &arraycopy_worklist) {
3003 GrowableArray<Node *> memnode_worklist;
3004 GrowableArray<PhiNode *> orig_phis;
3005 PhaseIterGVN *igvn = _igvn;
3006 uint new_index_start = (uint) _compile->num_alias_types();
3007 Arena* arena = Thread::current()->resource_area();
3008 VectorSet visited(arena);
3009 ideal_nodes.clear(); // Reset for use with set_map/get_map.
3010 uint unique_old = _compile->unique();
3011
3012 // Phase 1: Process possible allocations from alloc_worklist.
3013 // Create instance types for the CheckCastPP for allocations where possible.
3014 //
3015 // (Note: don't forget to change the order of the second AddP node on
3016 // the alloc_worklist if the order of the worklist processing is changed,
3017 // see the comment in find_second_addp().)
3018 //
3019 while (alloc_worklist.length() != 0) {
3020 Node *n = alloc_worklist.pop();
3021 uint ni = n->_idx;
3022 if (n->is_Call()) {
3023 CallNode *alloc = n->as_Call();
3024 // copy escape information to call node
3025 PointsToNode* ptn = ptnode_adr(alloc->_idx);
3026 PointsToNode::EscapeState es = ptn->escape_state();
3027 // We have an allocation or call which returns a Java object,
3028 // see if it is unescaped.
3029 if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable())
3030 continue;
3031 // Find CheckCastPP for the allocate or for the return value of a call
3032 n = alloc->result_cast();
3033 if (n == NULL) { // No uses except Initialize node
3034 if (alloc->is_Allocate()) {
3035 // Set the scalar_replaceable flag for allocation
3036 // so it could be eliminated if it has no uses.
3037 alloc->as_Allocate()->_is_scalar_replaceable = true;
3038 }
3039 if (alloc->is_CallStaticJava()) {
3040 // Set the scalar_replaceable flag for boxing method
3041 // so it could be eliminated if it has no uses.
3042 alloc->as_CallStaticJava()->_is_scalar_replaceable = true;
3043 }
3044 continue;
3045 }
3046 if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
3047 assert(!alloc->is_Allocate(), "allocation should have unique type");
3048 continue;
3049 }
3050
3051 // The inline code for Object.clone() casts the allocation result to
3052 // java.lang.Object and then to the actual type of the allocated
3053 // object. Detect this case and use the second cast.
3054 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
3055 // the allocation result is cast to java.lang.Object and then
3056 // to the actual Array type.
3057 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
3058 && (alloc->is_AllocateArray() ||
3059 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
3060 Node *cast2 = NULL;
3061 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3062 Node *use = n->fast_out(i);
3063 if (use->is_CheckCastPP()) {
3064 cast2 = use;
3065 break;
3066 }
3067 }
3068 if (cast2 != NULL) {
3069 n = cast2;
3070 } else {
3071 // Non-scalar replaceable if the allocation type is unknown statically
3072 // (reflection allocation), the object can't be restored during
3073 // deoptimization without precise type.
3074 continue;
3075 }
3076 }
3077
3078 const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
3079 if (t == NULL)
3080 continue; // not a TypeOopPtr
3081 if (!t->klass_is_exact())
3082 continue; // not an unique type
3083
3084 if (alloc->is_Allocate()) {
3085 // Set the scalar_replaceable flag for allocation
3086 // so it could be eliminated.
3087 alloc->as_Allocate()->_is_scalar_replaceable = true;
3088 }
3089 if (alloc->is_CallStaticJava()) {
3090 // Set the scalar_replaceable flag for boxing method
3091 // so it could be eliminated.
3092 alloc->as_CallStaticJava()->_is_scalar_replaceable = true;
3093 }
3094 set_escape_state(ptnode_adr(n->_idx), es); // CheckCastPP escape state
3095 // in order for an object to be scalar-replaceable, it must be:
3096 // - a direct allocation (not a call returning an object)
3097 // - non-escaping
3098 // - eligible to be a unique type
3099 // - not determined to be ineligible by escape analysis
3100 set_map(alloc, n);
3101 set_map(n, alloc);
3102 const TypeOopPtr* tinst = t->cast_to_instance_id(ni);
3103 igvn->hash_delete(n);
3104 igvn->set_type(n, tinst);
3105 n->raise_bottom_type(tinst);
3106 igvn->hash_insert(n);
3107 record_for_optimizer(n);
3108 if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) {
3109
3110 // First, put on the worklist all Field edges from Connection Graph
3111 // which is more accurate than putting immediate users from Ideal Graph.
3112 for (EdgeIterator e(ptn); e.has_next(); e.next()) {
3113 PointsToNode* tgt = e.get();
3114 if (tgt->is_Arraycopy()) {
3115 continue;
3116 }
3117 Node* use = tgt->ideal_node();
3118 assert(tgt->is_Field() && use->is_AddP(),
3119 "only AddP nodes are Field edges in CG");
3120 if (use->outcnt() > 0) { // Don't process dead nodes
3121 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
3122 if (addp2 != NULL) {
3123 assert(alloc->is_AllocateArray(),"array allocation was expected");
3124 alloc_worklist.append_if_missing(addp2);
3125 }
3126 alloc_worklist.append_if_missing(use);
3127 }
3128 }
3129
3130 // An allocation may have an Initialize which has raw stores. Scan
3131 // the users of the raw allocation result and push AddP users
3132 // on alloc_worklist.
3133 Node *raw_result = alloc->proj_out_or_null(TypeFunc::Parms);
3134 assert (raw_result != NULL, "must have an allocation result");
3135 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
3136 Node *use = raw_result->fast_out(i);
3137 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
3138 Node* addp2 = find_second_addp(use, raw_result);
3139 if (addp2 != NULL) {
3140 assert(alloc->is_AllocateArray(),"array allocation was expected");
3141 alloc_worklist.append_if_missing(addp2);
3142 }
3143 alloc_worklist.append_if_missing(use);
3144 } else if (use->is_MemBar()) {
3145 memnode_worklist.append_if_missing(use);
3146 }
3147 }
3148 }
3149 } else if (n->is_AddP()) {
3150 JavaObjectNode* jobj = unique_java_object(get_addp_base(n));
3151 if (jobj == NULL || jobj == phantom_obj) {
3152 #ifdef ASSERT
3153 ptnode_adr(get_addp_base(n)->_idx)->dump();
3154 ptnode_adr(n->_idx)->dump();
3155 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3156 #endif
3157 _compile->record_failure(C2Compiler::retry_no_escape_analysis());
3158 return;
3159 }
3160 Node *base = get_map(jobj->idx()); // CheckCastPP node
3161 if (!split_AddP(n, base)) continue; // wrong type from dead path
3162 } else if (n->is_Phi() ||
3163 n->is_CheckCastPP() ||
3164 n->is_EncodeP() ||
3165 n->is_DecodeN() ||
3166 n->is_ShenandoahBarrier() ||
3167 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
3168 if (visited.test_set(n->_idx)) {
3169 assert(n->is_Phi(), "loops only through Phi's");
3170 continue; // already processed
3171 }
3172 JavaObjectNode* jobj = unique_java_object(n);
3173 if (jobj == NULL || jobj == phantom_obj) {
3174 #ifdef ASSERT
3175 ptnode_adr(n->_idx)->dump();
3176 assert(jobj != NULL && jobj != phantom_obj, "escaped allocation");
3177 #endif
3178 _compile->record_failure(C2Compiler::retry_no_escape_analysis());
3179 return;
3180 } else {
3181 Node *val = get_map(jobj->idx()); // CheckCastPP node
3182 TypeNode *tn = n->as_Type();
3183 const TypeOopPtr* tinst = igvn->type(val)->isa_oopptr();
3184 assert(tinst != NULL && tinst->is_known_instance() &&
3185 tinst->instance_id() == jobj->idx() , "instance type expected.");
3186
3187 const Type *tn_type = igvn->type(tn);
3188 const TypeOopPtr *tn_t;
3189 if (tn_type->isa_narrowoop()) {
3190 tn_t = tn_type->make_ptr()->isa_oopptr();
3191 } else {
3192 tn_t = tn_type->isa_oopptr();
3193 }
3194 if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) {
3195 if (tn_type->isa_narrowoop()) {
3196 tn_type = tinst->make_narrowoop();
3197 } else {
3198 tn_type = tinst;
3199 }
3200 igvn->hash_delete(tn);
3201 igvn->set_type(tn, tn_type);
3202 tn->set_type(tn_type);
3203 igvn->hash_insert(tn);
3204 record_for_optimizer(n);
3205 } else {
3206 assert(tn_type == TypePtr::NULL_PTR ||
3207 tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()),
3208 "unexpected type");
3209 continue; // Skip dead path with different type
3210 }
3211 }
3212 } else {
3213 debug_only(n->dump();)
3214 assert(false, "EA: unexpected node");
3215 continue;
3216 }
3217 // push allocation's users on appropriate worklist
3218 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3219 Node *use = n->fast_out(i);
3220 if(use->is_Mem() && use->in(MemNode::Address) == n) {
3221 // Load/store to instance's field
3222 memnode_worklist.append_if_missing(use);
3223 } else if (use->is_MemBar()) {
3224 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3225 memnode_worklist.append_if_missing(use);
3226 }
3227 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
3228 Node* addp2 = find_second_addp(use, n);
3229 if (addp2 != NULL) {
3230 alloc_worklist.append_if_missing(addp2);
3231 }
3232 alloc_worklist.append_if_missing(use);
3233 } else if (use->is_Phi() ||
3234 use->is_CheckCastPP() ||
3235 use->is_EncodeNarrowPtr() ||
3236 use->is_DecodeNarrowPtr() ||
3237 use->is_ShenandoahBarrier() ||
3238 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
3239 alloc_worklist.append_if_missing(use);
3240 #ifdef ASSERT
3241 } else if (use->is_Mem()) {
3242 assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
3243 } else if (use->is_MergeMem()) {
3244 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3245 } else if (use->is_SafePoint()) {
3246 // Look for MergeMem nodes for calls which reference unique allocation
3247 // (through CheckCastPP nodes) even for debug info.
3248 Node* m = use->in(TypeFunc::Memory);
3249 if (m->is_MergeMem()) {
3250 assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3251 }
3252 } else if (use->Opcode() == Op_EncodeISOArray) {
3253 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3254 // EncodeISOArray overwrites destination array
3255 memnode_worklist.append_if_missing(use);
3256 }
3257 } else {
3258 uint op = use->Opcode();
3259 if ((op == Op_StrCompressedCopy || op == Op_StrInflatedCopy) &&
3260 (use->in(MemNode::Memory) == n)) {
3261 // They overwrite memory edge corresponding to destination array,
3262 memnode_worklist.append_if_missing(use);
3263 } else if (!(op == Op_CmpP || op == Op_Conv2B ||
3264 op == Op_CastP2X || op == Op_StoreCM ||
3265 op == Op_FastLock || op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives ||
3266 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3267 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar ||
3268 op == Op_ShenandoahWBMemProj ||
3269 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use))) {
3270 n->dump();
3271 use->dump();
3272 assert(false, "EA: missing allocation reference path");
3273 }
3274 #endif
3275 }
3276 }
3277
3278 }
3279
3280 // Go over all ArrayCopy nodes and if one of the inputs has a unique
3281 // type, record it in the ArrayCopy node so we know what memory this
3282 // node uses/modified.
3283 for (int next = 0; next < arraycopy_worklist.length(); next++) {
3284 ArrayCopyNode* ac = arraycopy_worklist.at(next);
3285 Node* dest = ac->in(ArrayCopyNode::Dest);
3286 if (dest->is_AddP()) {
3287 dest = get_addp_base(dest);
3288 }
3289 JavaObjectNode* jobj = unique_java_object(dest);
3290 if (jobj != NULL) {
3291 Node *base = get_map(jobj->idx());
3292 if (base != NULL) {
3293 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3294 ac->_dest_type = base_t;
3295 }
3296 }
3297 Node* src = ac->in(ArrayCopyNode::Src);
3298 if (src->is_AddP()) {
3299 src = get_addp_base(src);
3300 }
3301 jobj = unique_java_object(src);
3302 if (jobj != NULL) {
3303 Node* base = get_map(jobj->idx());
3304 if (base != NULL) {
3305 const TypeOopPtr *base_t = _igvn->type(base)->isa_oopptr();
3306 ac->_src_type = base_t;
3307 }
3308 }
3309 }
3310
3311 // New alias types were created in split_AddP().
3312 uint new_index_end = (uint) _compile->num_alias_types();
3313 assert(unique_old == _compile->unique(), "there should be no new ideal nodes after Phase 1");
3314
3315 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
3316 // compute new values for Memory inputs (the Memory inputs are not
3317 // actually updated until phase 4.)
3318 if (memnode_worklist.length() == 0)
3319 return; // nothing to do
3320 while (memnode_worklist.length() != 0) {
3321 Node *n = memnode_worklist.pop();
3322 if (visited.test_set(n->_idx))
3323 continue;
3324 if (n->is_Phi() || n->is_ClearArray()) {
3325 // we don't need to do anything, but the users must be pushed
3326 } else if (n->is_MemBar()) { // Initialize, MemBar nodes
3327 // we don't need to do anything, but the users must be pushed
3328 n = n->as_MemBar()->proj_out_or_null(TypeFunc::Memory);
3329 if (n == NULL)
3330 continue;
3331 } else if (n->Opcode() == Op_StrCompressedCopy ||
3332 n->Opcode() == Op_EncodeISOArray) {
3333 // get the memory projection
3334 n = n->find_out_with(Op_SCMemProj);
3335 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required");
3336 } else {
3337 assert(n->is_Mem(), "memory node required.");
3338 Node *addr = n->in(MemNode::Address);
3339 const Type *addr_t = igvn->type(addr);
3340 if (addr_t == Type::TOP)
3341 continue;
3342 assert (addr_t->isa_ptr() != NULL, "pointer type required.");
3343 int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
3344 assert ((uint)alias_idx < new_index_end, "wrong alias index");
3345 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis);
3346 if (_compile->failing()) {
3347 return;
3348 }
3349 if (mem != n->in(MemNode::Memory)) {
3350 // We delay the memory edge update since we need old one in
3351 // MergeMem code below when instances memory slices are separated.
3352 set_map(n, mem);
3353 }
3354 if (n->is_Load()) {
3355 continue; // don't push users
3356 } else if (n->is_LoadStore()) {
3357 // get the memory projection
3358 n = n->find_out_with(Op_SCMemProj);
3359 assert(n != NULL && n->Opcode() == Op_SCMemProj, "memory projection required");
3360 }
3361 }
3362 // push user on appropriate worklist
3363 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
3364 Node *use = n->fast_out(i);
3365 if (use->is_Phi() || use->is_ClearArray()) {
3366 memnode_worklist.append_if_missing(use);
3367 } else if (use->is_Mem() && use->in(MemNode::Memory) == n) {
3368 if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores
3369 continue;
3370 memnode_worklist.append_if_missing(use);
3371 } else if (use->is_MemBar()) {
3372 if (use->in(TypeFunc::Memory) == n) { // Ignore precedent edge
3373 memnode_worklist.append_if_missing(use);
3374 }
3375 #ifdef ASSERT
3376 } else if(use->is_Mem()) {
3377 assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
3378 } else if (use->is_MergeMem()) {
3379 assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
3380 } else if (use->Opcode() == Op_EncodeISOArray) {
3381 if (use->in(MemNode::Memory) == n || use->in(3) == n) {
3382 // EncodeISOArray overwrites destination array
3383 memnode_worklist.append_if_missing(use);
3384 }
3385 } else {
3386 uint op = use->Opcode();
3387 if ((use->in(MemNode::Memory) == n) &&
3388 (op == Op_StrCompressedCopy || op == Op_StrInflatedCopy)) {
3389 // They overwrite memory edge corresponding to destination array,
3390 memnode_worklist.append_if_missing(use);
3391 } else if (!(BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(use) ||
3392 op == Op_AryEq || op == Op_StrComp || op == Op_HasNegatives ||
3393 op == Op_StrCompressedCopy || op == Op_StrInflatedCopy ||
3394 op == Op_StrEquals || op == Op_StrIndexOf || op == Op_StrIndexOfChar)) {
3395 n->dump();
3396 use->dump();
3397 assert(false, "EA: missing memory path");
3398 }
3399 #endif
3400 }
3401 }
3402 }
3403
3404 // Phase 3: Process MergeMem nodes from mergemem_worklist.
3405 // Walk each memory slice moving the first node encountered of each
3406 // instance type to the the input corresponding to its alias index.
3407 uint length = _mergemem_worklist.length();
3408 for( uint next = 0; next < length; ++next ) {
3409 MergeMemNode* nmm = _mergemem_worklist.at(next);
3410 assert(!visited.test_set(nmm->_idx), "should not be visited before");
3411 // Note: we don't want to use MergeMemStream here because we only want to
3412 // scan inputs which exist at the start, not ones we add during processing.
3413 // Note 2: MergeMem may already contains instance memory slices added
3414 // during find_inst_mem() call when memory nodes were processed above.
3415 igvn->hash_delete(nmm);
3416 uint nslices = MIN2(nmm->req(), new_index_start);
3417 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
3418 Node* mem = nmm->in(i);
3419 Node* cur = NULL;
3420 if (mem == NULL || mem->is_top())
3421 continue;
3422 // First, update mergemem by moving memory nodes to corresponding slices
3423 // if their type became more precise since this mergemem was created.
3424 while (mem->is_Mem()) {
3425 const Type *at = igvn->type(mem->in(MemNode::Address));
3426 if (at != Type::TOP) {
3427 assert (at->isa_ptr() != NULL, "pointer type required.");
3428 uint idx = (uint)_compile->get_alias_index(at->is_ptr());
3429 if (idx == i) {
3430 if (cur == NULL)
3431 cur = mem;
3432 } else {
3433 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
3434 nmm->set_memory_at(idx, mem);
3435 }
3436 }
3437 }
3438 mem = mem->in(MemNode::Memory);
3439 }
3440 nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
3441 // Find any instance of the current type if we haven't encountered
3442 // already a memory slice of the instance along the memory chain.
3443 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3444 if((uint)_compile->get_general_index(ni) == i) {
3445 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
3446 if (nmm->is_empty_memory(m)) {
3447 Node* result = find_inst_mem(mem, ni, orig_phis);
3448 if (_compile->failing()) {
3449 return;
3450 }
3451 nmm->set_memory_at(ni, result);
3452 }
3453 }
3454 }
3455 }
3456 // Find the rest of instances values
3457 for (uint ni = new_index_start; ni < new_index_end; ni++) {
3458 const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
3459 Node* result = step_through_mergemem(nmm, ni, tinst);
3460 if (result == nmm->base_memory()) {
3461 // Didn't find instance memory, search through general slice recursively.
3462 result = nmm->memory_at(_compile->get_general_index(ni));
3463 result = find_inst_mem(result, ni, orig_phis);
3464 if (_compile->failing()) {
3465 return;
3466 }
3467 nmm->set_memory_at(ni, result);
3468 }
3469 }
3470 igvn->hash_insert(nmm);
3471 record_for_optimizer(nmm);
3472 }
3473
3474 // Phase 4: Update the inputs of non-instance memory Phis and
3475 // the Memory input of memnodes
3476 // First update the inputs of any non-instance Phi's from
3477 // which we split out an instance Phi. Note we don't have
3478 // to recursively process Phi's encounted on the input memory
3479 // chains as is done in split_memory_phi() since they will
3480 // also be processed here.
3481 for (int j = 0; j < orig_phis.length(); j++) {
3482 PhiNode *phi = orig_phis.at(j);
3483 int alias_idx = _compile->get_alias_index(phi->adr_type());
3484 igvn->hash_delete(phi);
3485 for (uint i = 1; i < phi->req(); i++) {
3486 Node *mem = phi->in(i);
3487 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis);
3488 if (_compile->failing()) {
3489 return;
3490 }
3491 if (mem != new_mem) {
3492 phi->set_req(i, new_mem);
3493 }
3494 }
3495 igvn->hash_insert(phi);
3496 record_for_optimizer(phi);
3497 }
3498
3499 // Update the memory inputs of MemNodes with the value we computed
3500 // in Phase 2 and move stores memory users to corresponding memory slices.
3501 // Disable memory split verification code until the fix for 6984348.
3502 // Currently it produces false negative results since it does not cover all cases.
3503 #if 0 // ifdef ASSERT
3504 visited.Reset();
3505 Node_Stack old_mems(arena, _compile->unique() >> 2);
3506 #endif
3507 for (uint i = 0; i < ideal_nodes.size(); i++) {
3508 Node* n = ideal_nodes.at(i);
3509 Node* nmem = get_map(n->_idx);
3510 assert(nmem != NULL, "sanity");
3511 if (n->is_Mem()) {
3512 #if 0 // ifdef ASSERT
3513 Node* old_mem = n->in(MemNode::Memory);
3514 if (!visited.test_set(old_mem->_idx)) {
3515 old_mems.push(old_mem, old_mem->outcnt());
3516 }
3517 #endif
3518 assert(n->in(MemNode::Memory) != nmem, "sanity");
3519 if (!n->is_Load()) {
3520 // Move memory users of a store first.
3521 move_inst_mem(n, orig_phis);
3522 }
3523 // Now update memory input
3524 igvn->hash_delete(n);
3525 n->set_req(MemNode::Memory, nmem);
3526 igvn->hash_insert(n);
3527 record_for_optimizer(n);
3528 } else {
3529 assert(n->is_Allocate() || n->is_CheckCastPP() ||
3530 n->is_AddP() || n->is_Phi(), "unknown node used for set_map()");
3531 }
3532 }
3533 #if 0 // ifdef ASSERT
3534 // Verify that memory was split correctly
3535 while (old_mems.is_nonempty()) {
3536 Node* old_mem = old_mems.node();
3537 uint old_cnt = old_mems.index();
3538 old_mems.pop();
3539 assert(old_cnt == old_mem->outcnt(), "old mem could be lost");
3540 }
3541 #endif
3542 }
3543
3544 #ifndef PRODUCT
3545 static const char *node_type_names[] = {
3546 "UnknownType",
3547 "JavaObject",
3548 "LocalVar",
3549 "Field",
3550 "Arraycopy"
3551 };
3552
3553 static const char *esc_names[] = {
3554 "UnknownEscape",
3555 "NoEscape",
3556 "ArgEscape",
3557 "GlobalEscape"
3558 };
3559
3560 void PointsToNode::dump(bool print_state) const {
3561 NodeType nt = node_type();
3562 tty->print("%s ", node_type_names[(int) nt]);
3563 if (print_state) {
3564 EscapeState es = escape_state();
3565 EscapeState fields_es = fields_escape_state();
3566 tty->print("%s(%s) ", esc_names[(int)es], esc_names[(int)fields_es]);
3567 if (nt == PointsToNode::JavaObject && !this->scalar_replaceable())
3568 tty->print("NSR ");
3569 }
3570 if (is_Field()) {
3571 FieldNode* f = (FieldNode*)this;
3572 if (f->is_oop())
3573 tty->print("oop ");
3574 if (f->offset() > 0)
3575 tty->print("+%d ", f->offset());
3576 tty->print("(");
3577 for (BaseIterator i(f); i.has_next(); i.next()) {
3578 PointsToNode* b = i.get();
3579 tty->print(" %d%s", b->idx(),(b->is_JavaObject() ? "P" : ""));
3580 }
3581 tty->print(" )");
3582 }
3583 tty->print("[");
3584 for (EdgeIterator i(this); i.has_next(); i.next()) {
3585 PointsToNode* e = i.get();
3586 tty->print(" %d%s%s", e->idx(),(e->is_JavaObject() ? "P" : (e->is_Field() ? "F" : "")), e->is_Arraycopy() ? "cp" : "");
3587 }
3588 tty->print(" [");
3589 for (UseIterator i(this); i.has_next(); i.next()) {
3590 PointsToNode* u = i.get();
3591 bool is_base = false;
3592 if (PointsToNode::is_base_use(u)) {
3593 is_base = true;
3594 u = PointsToNode::get_use_node(u)->as_Field();
3595 }
3596 tty->print(" %d%s%s", u->idx(), is_base ? "b" : "", u->is_Arraycopy() ? "cp" : "");
3597 }
3598 tty->print(" ]] ");
3599 if (_node == NULL)
3600 tty->print_cr("<null>");
3601 else
3602 _node->dump();
3603 }
3604
3605 void ConnectionGraph::dump(GrowableArray<PointsToNode*>& ptnodes_worklist) {
3606 bool first = true;
3607 int ptnodes_length = ptnodes_worklist.length();
3608 for (int i = 0; i < ptnodes_length; i++) {
3609 PointsToNode *ptn = ptnodes_worklist.at(i);
3610 if (ptn == NULL || !ptn->is_JavaObject())
3611 continue;
3612 PointsToNode::EscapeState es = ptn->escape_state();
3613 if ((es != PointsToNode::NoEscape) && !Verbose) {
3614 continue;
3615 }
3616 Node* n = ptn->ideal_node();
3617 if (n->is_Allocate() || (n->is_CallStaticJava() &&
3618 n->as_CallStaticJava()->is_boxing_method())) {
3619 if (first) {
3620 tty->cr();
3621 tty->print("======== Connection graph for ");
3622 _compile->method()->print_short_name();
3623 tty->cr();
3624 first = false;
3625 }
3626 ptn->dump();
3627 // Print all locals and fields which reference this allocation
3628 for (UseIterator j(ptn); j.has_next(); j.next()) {
3629 PointsToNode* use = j.get();
3630 if (use->is_LocalVar()) {
3631 use->dump(Verbose);
3632 } else if (Verbose) {
3633 use->dump();
3634 }
3635 }
3636 tty->cr();
3637 }
3638 }
3639 }
3640 #endif