Thu, 10 Sep 2009 10:36:24 -0700
6880574: C2 assert in escape.cpp:445 on linux-amd64
Summary: Look through chained AddP nodes in get_addp_base().
Reviewed-by: jrose
1 /*
2 * Copyright 2005-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
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23 */
25 #include "incls/_precompiled.incl"
26 #include "incls/_escape.cpp.incl"
28 void PointsToNode::add_edge(uint targIdx, PointsToNode::EdgeType et) {
29 uint v = (targIdx << EdgeShift) + ((uint) et);
30 if (_edges == NULL) {
31 Arena *a = Compile::current()->comp_arena();
32 _edges = new(a) GrowableArray<uint>(a, INITIAL_EDGE_COUNT, 0, 0);
33 }
34 _edges->append_if_missing(v);
35 }
37 void PointsToNode::remove_edge(uint targIdx, PointsToNode::EdgeType et) {
38 uint v = (targIdx << EdgeShift) + ((uint) et);
40 _edges->remove(v);
41 }
43 #ifndef PRODUCT
44 static const char *node_type_names[] = {
45 "UnknownType",
46 "JavaObject",
47 "LocalVar",
48 "Field"
49 };
51 static const char *esc_names[] = {
52 "UnknownEscape",
53 "NoEscape",
54 "ArgEscape",
55 "GlobalEscape"
56 };
58 static const char *edge_type_suffix[] = {
59 "?", // UnknownEdge
60 "P", // PointsToEdge
61 "D", // DeferredEdge
62 "F" // FieldEdge
63 };
65 void PointsToNode::dump(bool print_state) const {
66 NodeType nt = node_type();
67 tty->print("%s ", node_type_names[(int) nt]);
68 if (print_state) {
69 EscapeState es = escape_state();
70 tty->print("%s %s ", esc_names[(int) es], _scalar_replaceable ? "":"NSR");
71 }
72 tty->print("[[");
73 for (uint i = 0; i < edge_count(); i++) {
74 tty->print(" %d%s", edge_target(i), edge_type_suffix[(int) edge_type(i)]);
75 }
76 tty->print("]] ");
77 if (_node == NULL)
78 tty->print_cr("<null>");
79 else
80 _node->dump();
81 }
82 #endif
84 ConnectionGraph::ConnectionGraph(Compile * C) :
85 _nodes(C->comp_arena(), C->unique(), C->unique(), PointsToNode()),
86 _processed(C->comp_arena()),
87 _collecting(true),
88 _compile(C),
89 _node_map(C->comp_arena()) {
91 _phantom_object = C->top()->_idx,
92 add_node(C->top(), PointsToNode::JavaObject, PointsToNode::GlobalEscape,true);
94 // Add ConP(#NULL) and ConN(#NULL) nodes.
95 PhaseGVN* igvn = C->initial_gvn();
96 Node* oop_null = igvn->zerocon(T_OBJECT);
97 _oop_null = oop_null->_idx;
98 assert(_oop_null < C->unique(), "should be created already");
99 add_node(oop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
101 if (UseCompressedOops) {
102 Node* noop_null = igvn->zerocon(T_NARROWOOP);
103 _noop_null = noop_null->_idx;
104 assert(_noop_null < C->unique(), "should be created already");
105 add_node(noop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
106 }
107 }
109 void ConnectionGraph::add_pointsto_edge(uint from_i, uint to_i) {
110 PointsToNode *f = ptnode_adr(from_i);
111 PointsToNode *t = ptnode_adr(to_i);
113 assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
114 assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of PointsTo edge");
115 assert(t->node_type() == PointsToNode::JavaObject, "invalid destination of PointsTo edge");
116 f->add_edge(to_i, PointsToNode::PointsToEdge);
117 }
119 void ConnectionGraph::add_deferred_edge(uint from_i, uint to_i) {
120 PointsToNode *f = ptnode_adr(from_i);
121 PointsToNode *t = ptnode_adr(to_i);
123 assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
124 assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of Deferred edge");
125 assert(t->node_type() == PointsToNode::LocalVar || t->node_type() == PointsToNode::Field, "invalid destination of Deferred edge");
126 // don't add a self-referential edge, this can occur during removal of
127 // deferred edges
128 if (from_i != to_i)
129 f->add_edge(to_i, PointsToNode::DeferredEdge);
130 }
132 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
133 const Type *adr_type = phase->type(adr);
134 if (adr->is_AddP() && adr_type->isa_oopptr() == NULL &&
135 adr->in(AddPNode::Address)->is_Proj() &&
136 adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
137 // We are computing a raw address for a store captured by an Initialize
138 // compute an appropriate address type. AddP cases #3 and #5 (see below).
139 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
140 assert(offs != Type::OffsetBot ||
141 adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
142 "offset must be a constant or it is initialization of array");
143 return offs;
144 }
145 const TypePtr *t_ptr = adr_type->isa_ptr();
146 assert(t_ptr != NULL, "must be a pointer type");
147 return t_ptr->offset();
148 }
150 void ConnectionGraph::add_field_edge(uint from_i, uint to_i, int offset) {
151 PointsToNode *f = ptnode_adr(from_i);
152 PointsToNode *t = ptnode_adr(to_i);
154 assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
155 assert(f->node_type() == PointsToNode::JavaObject, "invalid destination of Field edge");
156 assert(t->node_type() == PointsToNode::Field, "invalid destination of Field edge");
157 assert (t->offset() == -1 || t->offset() == offset, "conflicting field offsets");
158 t->set_offset(offset);
160 f->add_edge(to_i, PointsToNode::FieldEdge);
161 }
163 void ConnectionGraph::set_escape_state(uint ni, PointsToNode::EscapeState es) {
164 PointsToNode *npt = ptnode_adr(ni);
165 PointsToNode::EscapeState old_es = npt->escape_state();
166 if (es > old_es)
167 npt->set_escape_state(es);
168 }
170 void ConnectionGraph::add_node(Node *n, PointsToNode::NodeType nt,
171 PointsToNode::EscapeState es, bool done) {
172 PointsToNode* ptadr = ptnode_adr(n->_idx);
173 ptadr->_node = n;
174 ptadr->set_node_type(nt);
176 // inline set_escape_state(idx, es);
177 PointsToNode::EscapeState old_es = ptadr->escape_state();
178 if (es > old_es)
179 ptadr->set_escape_state(es);
181 if (done)
182 _processed.set(n->_idx);
183 }
185 PointsToNode::EscapeState ConnectionGraph::escape_state(Node *n, PhaseTransform *phase) {
186 uint idx = n->_idx;
187 PointsToNode::EscapeState es;
189 // If we are still collecting or there were no non-escaping allocations
190 // we don't know the answer yet
191 if (_collecting)
192 return PointsToNode::UnknownEscape;
194 // if the node was created after the escape computation, return
195 // UnknownEscape
196 if (idx >= nodes_size())
197 return PointsToNode::UnknownEscape;
199 es = ptnode_adr(idx)->escape_state();
201 // if we have already computed a value, return it
202 if (es != PointsToNode::UnknownEscape &&
203 ptnode_adr(idx)->node_type() == PointsToNode::JavaObject)
204 return es;
206 // PointsTo() calls n->uncast() which can return a new ideal node.
207 if (n->uncast()->_idx >= nodes_size())
208 return PointsToNode::UnknownEscape;
210 // compute max escape state of anything this node could point to
211 VectorSet ptset(Thread::current()->resource_area());
212 PointsTo(ptset, n, phase);
213 for(VectorSetI i(&ptset); i.test() && es != PointsToNode::GlobalEscape; ++i) {
214 uint pt = i.elem;
215 PointsToNode::EscapeState pes = ptnode_adr(pt)->escape_state();
216 if (pes > es)
217 es = pes;
218 }
219 // cache the computed escape state
220 assert(es != PointsToNode::UnknownEscape, "should have computed an escape state");
221 ptnode_adr(idx)->set_escape_state(es);
222 return es;
223 }
225 void ConnectionGraph::PointsTo(VectorSet &ptset, Node * n, PhaseTransform *phase) {
226 VectorSet visited(Thread::current()->resource_area());
227 GrowableArray<uint> worklist;
229 #ifdef ASSERT
230 Node *orig_n = n;
231 #endif
233 n = n->uncast();
234 PointsToNode* npt = ptnode_adr(n->_idx);
236 // If we have a JavaObject, return just that object
237 if (npt->node_type() == PointsToNode::JavaObject) {
238 ptset.set(n->_idx);
239 return;
240 }
241 #ifdef ASSERT
242 if (npt->_node == NULL) {
243 if (orig_n != n)
244 orig_n->dump();
245 n->dump();
246 assert(npt->_node != NULL, "unregistered node");
247 }
248 #endif
249 worklist.push(n->_idx);
250 while(worklist.length() > 0) {
251 int ni = worklist.pop();
252 if (visited.test_set(ni))
253 continue;
255 PointsToNode* pn = ptnode_adr(ni);
256 // ensure that all inputs of a Phi have been processed
257 assert(!_collecting || !pn->_node->is_Phi() || _processed.test(ni),"");
259 int edges_processed = 0;
260 uint e_cnt = pn->edge_count();
261 for (uint e = 0; e < e_cnt; e++) {
262 uint etgt = pn->edge_target(e);
263 PointsToNode::EdgeType et = pn->edge_type(e);
264 if (et == PointsToNode::PointsToEdge) {
265 ptset.set(etgt);
266 edges_processed++;
267 } else if (et == PointsToNode::DeferredEdge) {
268 worklist.push(etgt);
269 edges_processed++;
270 } else {
271 assert(false,"neither PointsToEdge or DeferredEdge");
272 }
273 }
274 if (edges_processed == 0) {
275 // no deferred or pointsto edges found. Assume the value was set
276 // outside this method. Add the phantom object to the pointsto set.
277 ptset.set(_phantom_object);
278 }
279 }
280 }
282 void ConnectionGraph::remove_deferred(uint ni, GrowableArray<uint>* deferred_edges, VectorSet* visited) {
283 // This method is most expensive during ConnectionGraph construction.
284 // Reuse vectorSet and an additional growable array for deferred edges.
285 deferred_edges->clear();
286 visited->Clear();
288 visited->set(ni);
289 PointsToNode *ptn = ptnode_adr(ni);
291 // Mark current edges as visited and move deferred edges to separate array.
292 for (uint i = 0; i < ptn->edge_count(); ) {
293 uint t = ptn->edge_target(i);
294 #ifdef ASSERT
295 assert(!visited->test_set(t), "expecting no duplications");
296 #else
297 visited->set(t);
298 #endif
299 if (ptn->edge_type(i) == PointsToNode::DeferredEdge) {
300 ptn->remove_edge(t, PointsToNode::DeferredEdge);
301 deferred_edges->append(t);
302 } else {
303 i++;
304 }
305 }
306 for (int next = 0; next < deferred_edges->length(); ++next) {
307 uint t = deferred_edges->at(next);
308 PointsToNode *ptt = ptnode_adr(t);
309 uint e_cnt = ptt->edge_count();
310 for (uint e = 0; e < e_cnt; e++) {
311 uint etgt = ptt->edge_target(e);
312 if (visited->test_set(etgt))
313 continue;
315 PointsToNode::EdgeType et = ptt->edge_type(e);
316 if (et == PointsToNode::PointsToEdge) {
317 add_pointsto_edge(ni, etgt);
318 if(etgt == _phantom_object) {
319 // Special case - field set outside (globally escaping).
320 ptn->set_escape_state(PointsToNode::GlobalEscape);
321 }
322 } else if (et == PointsToNode::DeferredEdge) {
323 deferred_edges->append(etgt);
324 } else {
325 assert(false,"invalid connection graph");
326 }
327 }
328 }
329 }
332 // Add an edge to node given by "to_i" from any field of adr_i whose offset
333 // matches "offset" A deferred edge is added if to_i is a LocalVar, and
334 // a pointsto edge is added if it is a JavaObject
336 void ConnectionGraph::add_edge_from_fields(uint adr_i, uint to_i, int offs) {
337 PointsToNode* an = ptnode_adr(adr_i);
338 PointsToNode* to = ptnode_adr(to_i);
339 bool deferred = (to->node_type() == PointsToNode::LocalVar);
341 for (uint fe = 0; fe < an->edge_count(); fe++) {
342 assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
343 int fi = an->edge_target(fe);
344 PointsToNode* pf = ptnode_adr(fi);
345 int po = pf->offset();
346 if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
347 if (deferred)
348 add_deferred_edge(fi, to_i);
349 else
350 add_pointsto_edge(fi, to_i);
351 }
352 }
353 }
355 // Add a deferred edge from node given by "from_i" to any field of adr_i
356 // whose offset matches "offset".
357 void ConnectionGraph::add_deferred_edge_to_fields(uint from_i, uint adr_i, int offs) {
358 PointsToNode* an = ptnode_adr(adr_i);
359 for (uint fe = 0; fe < an->edge_count(); fe++) {
360 assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
361 int fi = an->edge_target(fe);
362 PointsToNode* pf = ptnode_adr(fi);
363 int po = pf->offset();
364 if (pf->edge_count() == 0) {
365 // we have not seen any stores to this field, assume it was set outside this method
366 add_pointsto_edge(fi, _phantom_object);
367 }
368 if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
369 add_deferred_edge(from_i, fi);
370 }
371 }
372 }
374 // Helper functions
376 static Node* get_addp_base(Node *addp) {
377 assert(addp->is_AddP(), "must be AddP");
378 //
379 // AddP cases for Base and Address inputs:
380 // case #1. Direct object's field reference:
381 // Allocate
382 // |
383 // Proj #5 ( oop result )
384 // |
385 // CheckCastPP (cast to instance type)
386 // | |
387 // AddP ( base == address )
388 //
389 // case #2. Indirect object's field reference:
390 // Phi
391 // |
392 // CastPP (cast to instance type)
393 // | |
394 // AddP ( base == address )
395 //
396 // case #3. Raw object's field reference for Initialize node:
397 // Allocate
398 // |
399 // Proj #5 ( oop result )
400 // top |
401 // \ |
402 // AddP ( base == top )
403 //
404 // case #4. Array's element reference:
405 // {CheckCastPP | CastPP}
406 // | | |
407 // | AddP ( array's element offset )
408 // | |
409 // AddP ( array's offset )
410 //
411 // case #5. Raw object's field reference for arraycopy stub call:
412 // The inline_native_clone() case when the arraycopy stub is called
413 // after the allocation before Initialize and CheckCastPP nodes.
414 // Allocate
415 // |
416 // Proj #5 ( oop result )
417 // | |
418 // AddP ( base == address )
419 //
420 // case #6. Constant Pool, ThreadLocal, CastX2P or
421 // Raw object's field reference:
422 // {ConP, ThreadLocal, CastX2P, raw Load}
423 // top |
424 // \ |
425 // AddP ( base == top )
426 //
427 // case #7. Klass's field reference.
428 // LoadKlass
429 // | |
430 // AddP ( base == address )
431 //
432 // case #8. narrow Klass's field reference.
433 // LoadNKlass
434 // |
435 // DecodeN
436 // | |
437 // AddP ( base == address )
438 //
439 Node *base = addp->in(AddPNode::Base)->uncast();
440 if (base->is_top()) { // The AddP case #3 and #6.
441 base = addp->in(AddPNode::Address)->uncast();
442 while (base->is_AddP()) {
443 // Case #6 (unsafe access) may have several chained AddP nodes.
444 assert(base->in(AddPNode::Base)->is_top(), "expected unsafe access address only");
445 base = base->in(AddPNode::Address)->uncast();
446 }
447 assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal ||
448 base->Opcode() == Op_CastX2P || base->is_DecodeN() ||
449 (base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) ||
450 (base->is_Proj() && base->in(0)->is_Allocate()), "sanity");
451 }
452 return base;
453 }
455 static Node* find_second_addp(Node* addp, Node* n) {
456 assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
458 Node* addp2 = addp->raw_out(0);
459 if (addp->outcnt() == 1 && addp2->is_AddP() &&
460 addp2->in(AddPNode::Base) == n &&
461 addp2->in(AddPNode::Address) == addp) {
463 assert(addp->in(AddPNode::Base) == n, "expecting the same base");
464 //
465 // Find array's offset to push it on worklist first and
466 // as result process an array's element offset first (pushed second)
467 // to avoid CastPP for the array's offset.
468 // Otherwise the inserted CastPP (LocalVar) will point to what
469 // the AddP (Field) points to. Which would be wrong since
470 // the algorithm expects the CastPP has the same point as
471 // as AddP's base CheckCastPP (LocalVar).
472 //
473 // ArrayAllocation
474 // |
475 // CheckCastPP
476 // |
477 // memProj (from ArrayAllocation CheckCastPP)
478 // | ||
479 // | || Int (element index)
480 // | || | ConI (log(element size))
481 // | || | /
482 // | || LShift
483 // | || /
484 // | AddP (array's element offset)
485 // | |
486 // | | ConI (array's offset: #12(32-bits) or #24(64-bits))
487 // | / /
488 // AddP (array's offset)
489 // |
490 // Load/Store (memory operation on array's element)
491 //
492 return addp2;
493 }
494 return NULL;
495 }
497 //
498 // Adjust the type and inputs of an AddP which computes the
499 // address of a field of an instance
500 //
501 bool ConnectionGraph::split_AddP(Node *addp, Node *base, PhaseGVN *igvn) {
502 const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
503 assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
504 const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
505 if (t == NULL) {
506 // We are computing a raw address for a store captured by an Initialize
507 // compute an appropriate address type (cases #3 and #5).
508 assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
509 assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
510 intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
511 assert(offs != Type::OffsetBot, "offset must be a constant");
512 t = base_t->add_offset(offs)->is_oopptr();
513 }
514 int inst_id = base_t->instance_id();
515 assert(!t->is_known_instance() || t->instance_id() == inst_id,
516 "old type must be non-instance or match new type");
518 // The type 't' could be subclass of 'base_t'.
519 // As result t->offset() could be large then base_t's size and it will
520 // cause the failure in add_offset() with narrow oops since TypeOopPtr()
521 // constructor verifies correctness of the offset.
522 //
523 // It could happened on subclass's branch (from the type profiling
524 // inlining) which was not eliminated during parsing since the exactness
525 // of the allocation type was not propagated to the subclass type check.
526 //
527 // Do nothing for such AddP node and don't process its users since
528 // this code branch will go away.
529 //
530 if (!t->is_known_instance() &&
531 !t->klass()->equals(base_t->klass()) &&
532 t->klass()->is_subtype_of(base_t->klass())) {
533 return false; // bail out
534 }
536 const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
537 // Do NOT remove the next call: ensure an new alias index is allocated
538 // for the instance type
539 int alias_idx = _compile->get_alias_index(tinst);
540 igvn->set_type(addp, tinst);
541 // record the allocation in the node map
542 set_map(addp->_idx, get_map(base->_idx));
544 // Set addp's Base and Address to 'base'.
545 Node *abase = addp->in(AddPNode::Base);
546 Node *adr = addp->in(AddPNode::Address);
547 if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
548 adr->in(0)->_idx == (uint)inst_id) {
549 // Skip AddP cases #3 and #5.
550 } else {
551 assert(!abase->is_top(), "sanity"); // AddP case #3
552 if (abase != base) {
553 igvn->hash_delete(addp);
554 addp->set_req(AddPNode::Base, base);
555 if (abase == adr) {
556 addp->set_req(AddPNode::Address, base);
557 } else {
558 // AddP case #4 (adr is array's element offset AddP node)
559 #ifdef ASSERT
560 const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
561 assert(adr->is_AddP() && atype != NULL &&
562 atype->instance_id() == inst_id, "array's element offset should be processed first");
563 #endif
564 }
565 igvn->hash_insert(addp);
566 }
567 }
568 // Put on IGVN worklist since at least addp's type was changed above.
569 record_for_optimizer(addp);
570 return true;
571 }
573 //
574 // Create a new version of orig_phi if necessary. Returns either the newly
575 // created phi or an existing phi. Sets create_new to indicate wheter a new
576 // phi was created. Cache the last newly created phi in the node map.
577 //
578 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, PhaseGVN *igvn, bool &new_created) {
579 Compile *C = _compile;
580 new_created = false;
581 int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
582 // nothing to do if orig_phi is bottom memory or matches alias_idx
583 if (phi_alias_idx == alias_idx) {
584 return orig_phi;
585 }
586 // Have we recently created a Phi for this alias index?
587 PhiNode *result = get_map_phi(orig_phi->_idx);
588 if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
589 return result;
590 }
591 // Previous check may fail when the same wide memory Phi was split into Phis
592 // for different memory slices. Search all Phis for this region.
593 if (result != NULL) {
594 Node* region = orig_phi->in(0);
595 for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
596 Node* phi = region->fast_out(i);
597 if (phi->is_Phi() &&
598 C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
599 assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
600 return phi->as_Phi();
601 }
602 }
603 }
604 if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) {
605 if (C->do_escape_analysis() == true && !C->failing()) {
606 // Retry compilation without escape analysis.
607 // If this is the first failure, the sentinel string will "stick"
608 // to the Compile object, and the C2Compiler will see it and retry.
609 C->record_failure(C2Compiler::retry_no_escape_analysis());
610 }
611 return NULL;
612 }
613 orig_phi_worklist.append_if_missing(orig_phi);
614 const TypePtr *atype = C->get_adr_type(alias_idx);
615 result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
616 C->copy_node_notes_to(result, orig_phi);
617 set_map_phi(orig_phi->_idx, result);
618 igvn->set_type(result, result->bottom_type());
619 record_for_optimizer(result);
620 new_created = true;
621 return result;
622 }
624 //
625 // Return a new version of Memory Phi "orig_phi" with the inputs having the
626 // specified alias index.
627 //
628 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *> &orig_phi_worklist, PhaseGVN *igvn) {
630 assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
631 Compile *C = _compile;
632 bool new_phi_created;
633 PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created);
634 if (!new_phi_created) {
635 return result;
636 }
638 GrowableArray<PhiNode *> phi_list;
639 GrowableArray<uint> cur_input;
641 PhiNode *phi = orig_phi;
642 uint idx = 1;
643 bool finished = false;
644 while(!finished) {
645 while (idx < phi->req()) {
646 Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn);
647 if (mem != NULL && mem->is_Phi()) {
648 PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created);
649 if (new_phi_created) {
650 // found an phi for which we created a new split, push current one on worklist and begin
651 // processing new one
652 phi_list.push(phi);
653 cur_input.push(idx);
654 phi = mem->as_Phi();
655 result = newphi;
656 idx = 1;
657 continue;
658 } else {
659 mem = newphi;
660 }
661 }
662 if (C->failing()) {
663 return NULL;
664 }
665 result->set_req(idx++, mem);
666 }
667 #ifdef ASSERT
668 // verify that the new Phi has an input for each input of the original
669 assert( phi->req() == result->req(), "must have same number of inputs.");
670 assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
671 #endif
672 // Check if all new phi's inputs have specified alias index.
673 // Otherwise use old phi.
674 for (uint i = 1; i < phi->req(); i++) {
675 Node* in = result->in(i);
676 assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
677 }
678 // we have finished processing a Phi, see if there are any more to do
679 finished = (phi_list.length() == 0 );
680 if (!finished) {
681 phi = phi_list.pop();
682 idx = cur_input.pop();
683 PhiNode *prev_result = get_map_phi(phi->_idx);
684 prev_result->set_req(idx++, result);
685 result = prev_result;
686 }
687 }
688 return result;
689 }
692 //
693 // The next methods are derived from methods in MemNode.
694 //
695 static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *tinst) {
696 Node *mem = mmem;
697 // TypeInstPtr::NOTNULL+any is an OOP with unknown offset - generally
698 // means an array I have not precisely typed yet. Do not do any
699 // alias stuff with it any time soon.
700 if( tinst->base() != Type::AnyPtr &&
701 !(tinst->klass()->is_java_lang_Object() &&
702 tinst->offset() == Type::OffsetBot) ) {
703 mem = mmem->memory_at(alias_idx);
704 // Update input if it is progress over what we have now
705 }
706 return mem;
707 }
709 //
710 // Search memory chain of "mem" to find a MemNode whose address
711 // is the specified alias index.
712 //
713 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *> &orig_phis, PhaseGVN *phase) {
714 if (orig_mem == NULL)
715 return orig_mem;
716 Compile* C = phase->C;
717 const TypeOopPtr *tinst = C->get_adr_type(alias_idx)->isa_oopptr();
718 bool is_instance = (tinst != NULL) && tinst->is_known_instance();
719 Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
720 Node *prev = NULL;
721 Node *result = orig_mem;
722 while (prev != result) {
723 prev = result;
724 if (result == start_mem)
725 break; // hit one of our sentinels
726 if (result->is_Mem()) {
727 const Type *at = phase->type(result->in(MemNode::Address));
728 if (at != Type::TOP) {
729 assert (at->isa_ptr() != NULL, "pointer type required.");
730 int idx = C->get_alias_index(at->is_ptr());
731 if (idx == alias_idx)
732 break;
733 }
734 result = result->in(MemNode::Memory);
735 }
736 if (!is_instance)
737 continue; // don't search further for non-instance types
738 // skip over a call which does not affect this memory slice
739 if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
740 Node *proj_in = result->in(0);
741 if (proj_in->is_Allocate() && proj_in->_idx == (uint)tinst->instance_id()) {
742 break; // hit one of our sentinels
743 } else if (proj_in->is_Call()) {
744 CallNode *call = proj_in->as_Call();
745 if (!call->may_modify(tinst, phase)) {
746 result = call->in(TypeFunc::Memory);
747 }
748 } else if (proj_in->is_Initialize()) {
749 AllocateNode* alloc = proj_in->as_Initialize()->allocation();
750 // Stop if this is the initialization for the object instance which
751 // which contains this memory slice, otherwise skip over it.
752 if (alloc == NULL || alloc->_idx != (uint)tinst->instance_id()) {
753 result = proj_in->in(TypeFunc::Memory);
754 }
755 } else if (proj_in->is_MemBar()) {
756 result = proj_in->in(TypeFunc::Memory);
757 }
758 } else if (result->is_MergeMem()) {
759 MergeMemNode *mmem = result->as_MergeMem();
760 result = step_through_mergemem(mmem, alias_idx, tinst);
761 if (result == mmem->base_memory()) {
762 // Didn't find instance memory, search through general slice recursively.
763 result = mmem->memory_at(C->get_general_index(alias_idx));
764 result = find_inst_mem(result, alias_idx, orig_phis, phase);
765 if (C->failing()) {
766 return NULL;
767 }
768 mmem->set_memory_at(alias_idx, result);
769 }
770 } else if (result->is_Phi() &&
771 C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
772 Node *un = result->as_Phi()->unique_input(phase);
773 if (un != NULL) {
774 result = un;
775 } else {
776 break;
777 }
778 } else if (result->Opcode() == Op_SCMemProj) {
779 assert(result->in(0)->is_LoadStore(), "sanity");
780 const Type *at = phase->type(result->in(0)->in(MemNode::Address));
781 if (at != Type::TOP) {
782 assert (at->isa_ptr() != NULL, "pointer type required.");
783 int idx = C->get_alias_index(at->is_ptr());
784 assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field");
785 break;
786 }
787 result = result->in(0)->in(MemNode::Memory);
788 }
789 }
790 if (result->is_Phi()) {
791 PhiNode *mphi = result->as_Phi();
792 assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
793 const TypePtr *t = mphi->adr_type();
794 if (C->get_alias_index(t) != alias_idx) {
795 // Create a new Phi with the specified alias index type.
796 result = split_memory_phi(mphi, alias_idx, orig_phis, phase);
797 } else if (!is_instance) {
798 // Push all non-instance Phis on the orig_phis worklist to update inputs
799 // during Phase 4 if needed.
800 orig_phis.append_if_missing(mphi);
801 }
802 }
803 // the result is either MemNode, PhiNode, InitializeNode.
804 return result;
805 }
808 //
809 // Convert the types of unescaped object to instance types where possible,
810 // propagate the new type information through the graph, and update memory
811 // edges and MergeMem inputs to reflect the new type.
812 //
813 // We start with allocations (and calls which may be allocations) on alloc_worklist.
814 // The processing is done in 4 phases:
815 //
816 // Phase 1: Process possible allocations from alloc_worklist. Create instance
817 // types for the CheckCastPP for allocations where possible.
818 // Propagate the the new types through users as follows:
819 // casts and Phi: push users on alloc_worklist
820 // AddP: cast Base and Address inputs to the instance type
821 // push any AddP users on alloc_worklist and push any memnode
822 // users onto memnode_worklist.
823 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
824 // search the Memory chain for a store with the appropriate type
825 // address type. If a Phi is found, create a new version with
826 // the appropriate memory slices from each of the Phi inputs.
827 // For stores, process the users as follows:
828 // MemNode: push on memnode_worklist
829 // MergeMem: push on mergemem_worklist
830 // Phase 3: Process MergeMem nodes from mergemem_worklist. Walk each memory slice
831 // moving the first node encountered of each instance type to the
832 // the input corresponding to its alias index.
833 // appropriate memory slice.
834 // Phase 4: Update the inputs of non-instance memory Phis and the Memory input of memnodes.
835 //
836 // In the following example, the CheckCastPP nodes are the cast of allocation
837 // results and the allocation of node 29 is unescaped and eligible to be an
838 // instance type.
839 //
840 // We start with:
841 //
842 // 7 Parm #memory
843 // 10 ConI "12"
844 // 19 CheckCastPP "Foo"
845 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
846 // 29 CheckCastPP "Foo"
847 // 30 AddP _ 29 29 10 Foo+12 alias_index=4
848 //
849 // 40 StoreP 25 7 20 ... alias_index=4
850 // 50 StoreP 35 40 30 ... alias_index=4
851 // 60 StoreP 45 50 20 ... alias_index=4
852 // 70 LoadP _ 60 30 ... alias_index=4
853 // 80 Phi 75 50 60 Memory alias_index=4
854 // 90 LoadP _ 80 30 ... alias_index=4
855 // 100 LoadP _ 80 20 ... alias_index=4
856 //
857 //
858 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
859 // and creating a new alias index for node 30. This gives:
860 //
861 // 7 Parm #memory
862 // 10 ConI "12"
863 // 19 CheckCastPP "Foo"
864 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
865 // 29 CheckCastPP "Foo" iid=24
866 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
867 //
868 // 40 StoreP 25 7 20 ... alias_index=4
869 // 50 StoreP 35 40 30 ... alias_index=6
870 // 60 StoreP 45 50 20 ... alias_index=4
871 // 70 LoadP _ 60 30 ... alias_index=6
872 // 80 Phi 75 50 60 Memory alias_index=4
873 // 90 LoadP _ 80 30 ... alias_index=6
874 // 100 LoadP _ 80 20 ... alias_index=4
875 //
876 // In phase 2, new memory inputs are computed for the loads and stores,
877 // And a new version of the phi is created. In phase 4, the inputs to
878 // node 80 are updated and then the memory nodes are updated with the
879 // values computed in phase 2. This results in:
880 //
881 // 7 Parm #memory
882 // 10 ConI "12"
883 // 19 CheckCastPP "Foo"
884 // 20 AddP _ 19 19 10 Foo+12 alias_index=4
885 // 29 CheckCastPP "Foo" iid=24
886 // 30 AddP _ 29 29 10 Foo+12 alias_index=6 iid=24
887 //
888 // 40 StoreP 25 7 20 ... alias_index=4
889 // 50 StoreP 35 7 30 ... alias_index=6
890 // 60 StoreP 45 40 20 ... alias_index=4
891 // 70 LoadP _ 50 30 ... alias_index=6
892 // 80 Phi 75 40 60 Memory alias_index=4
893 // 120 Phi 75 50 50 Memory alias_index=6
894 // 90 LoadP _ 120 30 ... alias_index=6
895 // 100 LoadP _ 80 20 ... alias_index=4
896 //
897 void ConnectionGraph::split_unique_types(GrowableArray<Node *> &alloc_worklist) {
898 GrowableArray<Node *> memnode_worklist;
899 GrowableArray<Node *> mergemem_worklist;
900 GrowableArray<PhiNode *> orig_phis;
901 PhaseGVN *igvn = _compile->initial_gvn();
902 uint new_index_start = (uint) _compile->num_alias_types();
903 VectorSet visited(Thread::current()->resource_area());
904 VectorSet ptset(Thread::current()->resource_area());
907 // Phase 1: Process possible allocations from alloc_worklist.
908 // Create instance types for the CheckCastPP for allocations where possible.
909 //
910 // (Note: don't forget to change the order of the second AddP node on
911 // the alloc_worklist if the order of the worklist processing is changed,
912 // see the comment in find_second_addp().)
913 //
914 while (alloc_worklist.length() != 0) {
915 Node *n = alloc_worklist.pop();
916 uint ni = n->_idx;
917 const TypeOopPtr* tinst = NULL;
918 if (n->is_Call()) {
919 CallNode *alloc = n->as_Call();
920 // copy escape information to call node
921 PointsToNode* ptn = ptnode_adr(alloc->_idx);
922 PointsToNode::EscapeState es = escape_state(alloc, igvn);
923 // We have an allocation or call which returns a Java object,
924 // see if it is unescaped.
925 if (es != PointsToNode::NoEscape || !ptn->_scalar_replaceable)
926 continue;
928 // Find CheckCastPP for the allocate or for the return value of a call
929 n = alloc->result_cast();
930 if (n == NULL) { // No uses except Initialize node
931 if (alloc->is_Allocate()) {
932 // Set the scalar_replaceable flag for allocation
933 // so it could be eliminated if it has no uses.
934 alloc->as_Allocate()->_is_scalar_replaceable = true;
935 }
936 continue;
937 }
938 if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
939 assert(!alloc->is_Allocate(), "allocation should have unique type");
940 continue;
941 }
943 // The inline code for Object.clone() casts the allocation result to
944 // java.lang.Object and then to the actual type of the allocated
945 // object. Detect this case and use the second cast.
946 // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
947 // the allocation result is cast to java.lang.Object and then
948 // to the actual Array type.
949 if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
950 && (alloc->is_AllocateArray() ||
951 igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
952 Node *cast2 = NULL;
953 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
954 Node *use = n->fast_out(i);
955 if (use->is_CheckCastPP()) {
956 cast2 = use;
957 break;
958 }
959 }
960 if (cast2 != NULL) {
961 n = cast2;
962 } else {
963 // Non-scalar replaceable if the allocation type is unknown statically
964 // (reflection allocation), the object can't be restored during
965 // deoptimization without precise type.
966 continue;
967 }
968 }
969 if (alloc->is_Allocate()) {
970 // Set the scalar_replaceable flag for allocation
971 // so it could be eliminated.
972 alloc->as_Allocate()->_is_scalar_replaceable = true;
973 }
974 set_escape_state(n->_idx, es);
975 // in order for an object to be scalar-replaceable, it must be:
976 // - a direct allocation (not a call returning an object)
977 // - non-escaping
978 // - eligible to be a unique type
979 // - not determined to be ineligible by escape analysis
980 set_map(alloc->_idx, n);
981 set_map(n->_idx, alloc);
982 const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
983 if (t == NULL)
984 continue; // not a TypeInstPtr
985 tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni);
986 igvn->hash_delete(n);
987 igvn->set_type(n, tinst);
988 n->raise_bottom_type(tinst);
989 igvn->hash_insert(n);
990 record_for_optimizer(n);
991 if (alloc->is_Allocate() && ptn->_scalar_replaceable &&
992 (t->isa_instptr() || t->isa_aryptr())) {
994 // First, put on the worklist all Field edges from Connection Graph
995 // which is more accurate then putting immediate users from Ideal Graph.
996 for (uint e = 0; e < ptn->edge_count(); e++) {
997 Node *use = ptnode_adr(ptn->edge_target(e))->_node;
998 assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(),
999 "only AddP nodes are Field edges in CG");
1000 if (use->outcnt() > 0) { // Don't process dead nodes
1001 Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
1002 if (addp2 != NULL) {
1003 assert(alloc->is_AllocateArray(),"array allocation was expected");
1004 alloc_worklist.append_if_missing(addp2);
1005 }
1006 alloc_worklist.append_if_missing(use);
1007 }
1008 }
1010 // An allocation may have an Initialize which has raw stores. Scan
1011 // the users of the raw allocation result and push AddP users
1012 // on alloc_worklist.
1013 Node *raw_result = alloc->proj_out(TypeFunc::Parms);
1014 assert (raw_result != NULL, "must have an allocation result");
1015 for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
1016 Node *use = raw_result->fast_out(i);
1017 if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
1018 Node* addp2 = find_second_addp(use, raw_result);
1019 if (addp2 != NULL) {
1020 assert(alloc->is_AllocateArray(),"array allocation was expected");
1021 alloc_worklist.append_if_missing(addp2);
1022 }
1023 alloc_worklist.append_if_missing(use);
1024 } else if (use->is_Initialize()) {
1025 memnode_worklist.append_if_missing(use);
1026 }
1027 }
1028 }
1029 } else if (n->is_AddP()) {
1030 ptset.Clear();
1031 PointsTo(ptset, get_addp_base(n), igvn);
1032 assert(ptset.Size() == 1, "AddP address is unique");
1033 uint elem = ptset.getelem(); // Allocation node's index
1034 if (elem == _phantom_object)
1035 continue; // Assume the value was set outside this method.
1036 Node *base = get_map(elem); // CheckCastPP node
1037 if (!split_AddP(n, base, igvn)) continue; // wrong type
1038 tinst = igvn->type(base)->isa_oopptr();
1039 } else if (n->is_Phi() ||
1040 n->is_CheckCastPP() ||
1041 n->is_EncodeP() ||
1042 n->is_DecodeN() ||
1043 (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
1044 if (visited.test_set(n->_idx)) {
1045 assert(n->is_Phi(), "loops only through Phi's");
1046 continue; // already processed
1047 }
1048 ptset.Clear();
1049 PointsTo(ptset, n, igvn);
1050 if (ptset.Size() == 1) {
1051 uint elem = ptset.getelem(); // Allocation node's index
1052 if (elem == _phantom_object)
1053 continue; // Assume the value was set outside this method.
1054 Node *val = get_map(elem); // CheckCastPP node
1055 TypeNode *tn = n->as_Type();
1056 tinst = igvn->type(val)->isa_oopptr();
1057 assert(tinst != NULL && tinst->is_known_instance() &&
1058 (uint)tinst->instance_id() == elem , "instance type expected.");
1060 const Type *tn_type = igvn->type(tn);
1061 const TypeOopPtr *tn_t;
1062 if (tn_type->isa_narrowoop()) {
1063 tn_t = tn_type->make_ptr()->isa_oopptr();
1064 } else {
1065 tn_t = tn_type->isa_oopptr();
1066 }
1068 if (tn_t != NULL &&
1069 tinst->cast_to_instance_id(TypeOopPtr::InstanceBot)->higher_equal(tn_t)) {
1070 if (tn_type->isa_narrowoop()) {
1071 tn_type = tinst->make_narrowoop();
1072 } else {
1073 tn_type = tinst;
1074 }
1075 igvn->hash_delete(tn);
1076 igvn->set_type(tn, tn_type);
1077 tn->set_type(tn_type);
1078 igvn->hash_insert(tn);
1079 record_for_optimizer(n);
1080 } else {
1081 continue; // wrong type
1082 }
1083 }
1084 } else {
1085 continue;
1086 }
1087 // push users on appropriate worklist
1088 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1089 Node *use = n->fast_out(i);
1090 if(use->is_Mem() && use->in(MemNode::Address) == n) {
1091 memnode_worklist.append_if_missing(use);
1092 } else if (use->is_Initialize()) {
1093 memnode_worklist.append_if_missing(use);
1094 } else if (use->is_MergeMem()) {
1095 mergemem_worklist.append_if_missing(use);
1096 } else if (use->is_SafePoint() && tinst != NULL) {
1097 // Look for MergeMem nodes for calls which reference unique allocation
1098 // (through CheckCastPP nodes) even for debug info.
1099 Node* m = use->in(TypeFunc::Memory);
1100 uint iid = tinst->instance_id();
1101 while (m->is_Proj() && m->in(0)->is_SafePoint() &&
1102 m->in(0) != use && !m->in(0)->_idx != iid) {
1103 m = m->in(0)->in(TypeFunc::Memory);
1104 }
1105 if (m->is_MergeMem()) {
1106 mergemem_worklist.append_if_missing(m);
1107 }
1108 } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
1109 Node* addp2 = find_second_addp(use, n);
1110 if (addp2 != NULL) {
1111 alloc_worklist.append_if_missing(addp2);
1112 }
1113 alloc_worklist.append_if_missing(use);
1114 } else if (use->is_Phi() ||
1115 use->is_CheckCastPP() ||
1116 use->is_EncodeP() ||
1117 use->is_DecodeN() ||
1118 (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
1119 alloc_worklist.append_if_missing(use);
1120 }
1121 }
1123 }
1124 // New alias types were created in split_AddP().
1125 uint new_index_end = (uint) _compile->num_alias_types();
1127 // Phase 2: Process MemNode's from memnode_worklist. compute new address type and
1128 // compute new values for Memory inputs (the Memory inputs are not
1129 // actually updated until phase 4.)
1130 if (memnode_worklist.length() == 0)
1131 return; // nothing to do
1133 while (memnode_worklist.length() != 0) {
1134 Node *n = memnode_worklist.pop();
1135 if (visited.test_set(n->_idx))
1136 continue;
1137 if (n->is_Phi()) {
1138 assert(n->as_Phi()->adr_type() != TypePtr::BOTTOM, "narrow memory slice required");
1139 // we don't need to do anything, but the users must be pushed if we haven't processed
1140 // this Phi before
1141 } else if (n->is_Initialize()) {
1142 // we don't need to do anything, but the users of the memory projection must be pushed
1143 n = n->as_Initialize()->proj_out(TypeFunc::Memory);
1144 if (n == NULL)
1145 continue;
1146 } else {
1147 assert(n->is_Mem(), "memory node required.");
1148 Node *addr = n->in(MemNode::Address);
1149 assert(addr->is_AddP(), "AddP required");
1150 const Type *addr_t = igvn->type(addr);
1151 if (addr_t == Type::TOP)
1152 continue;
1153 assert (addr_t->isa_ptr() != NULL, "pointer type required.");
1154 int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
1155 assert ((uint)alias_idx < new_index_end, "wrong alias index");
1156 Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn);
1157 if (_compile->failing()) {
1158 return;
1159 }
1160 if (mem != n->in(MemNode::Memory)) {
1161 set_map(n->_idx, mem);
1162 ptnode_adr(n->_idx)->_node = n;
1163 }
1164 if (n->is_Load()) {
1165 continue; // don't push users
1166 } else if (n->is_LoadStore()) {
1167 // get the memory projection
1168 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1169 Node *use = n->fast_out(i);
1170 if (use->Opcode() == Op_SCMemProj) {
1171 n = use;
1172 break;
1173 }
1174 }
1175 assert(n->Opcode() == Op_SCMemProj, "memory projection required");
1176 }
1177 }
1178 // push user on appropriate worklist
1179 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1180 Node *use = n->fast_out(i);
1181 if (use->is_Phi()) {
1182 memnode_worklist.append_if_missing(use);
1183 } else if(use->is_Mem() && use->in(MemNode::Memory) == n) {
1184 memnode_worklist.append_if_missing(use);
1185 } else if (use->is_Initialize()) {
1186 memnode_worklist.append_if_missing(use);
1187 } else if (use->is_MergeMem()) {
1188 mergemem_worklist.append_if_missing(use);
1189 }
1190 }
1191 }
1193 // Phase 3: Process MergeMem nodes from mergemem_worklist.
1194 // Walk each memory moving the first node encountered of each
1195 // instance type to the the input corresponding to its alias index.
1196 while (mergemem_worklist.length() != 0) {
1197 Node *n = mergemem_worklist.pop();
1198 assert(n->is_MergeMem(), "MergeMem node required.");
1199 if (visited.test_set(n->_idx))
1200 continue;
1201 MergeMemNode *nmm = n->as_MergeMem();
1202 // Note: we don't want to use MergeMemStream here because we only want to
1203 // scan inputs which exist at the start, not ones we add during processing.
1204 uint nslices = nmm->req();
1205 igvn->hash_delete(nmm);
1206 for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
1207 Node* mem = nmm->in(i);
1208 Node* cur = NULL;
1209 if (mem == NULL || mem->is_top())
1210 continue;
1211 while (mem->is_Mem()) {
1212 const Type *at = igvn->type(mem->in(MemNode::Address));
1213 if (at != Type::TOP) {
1214 assert (at->isa_ptr() != NULL, "pointer type required.");
1215 uint idx = (uint)_compile->get_alias_index(at->is_ptr());
1216 if (idx == i) {
1217 if (cur == NULL)
1218 cur = mem;
1219 } else {
1220 if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
1221 nmm->set_memory_at(idx, mem);
1222 }
1223 }
1224 }
1225 mem = mem->in(MemNode::Memory);
1226 }
1227 nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
1228 // Find any instance of the current type if we haven't encountered
1229 // a value of the instance along the chain.
1230 for (uint ni = new_index_start; ni < new_index_end; ni++) {
1231 if((uint)_compile->get_general_index(ni) == i) {
1232 Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
1233 if (nmm->is_empty_memory(m)) {
1234 Node* result = find_inst_mem(mem, ni, orig_phis, igvn);
1235 if (_compile->failing()) {
1236 return;
1237 }
1238 nmm->set_memory_at(ni, result);
1239 }
1240 }
1241 }
1242 }
1243 // Find the rest of instances values
1244 for (uint ni = new_index_start; ni < new_index_end; ni++) {
1245 const TypeOopPtr *tinst = igvn->C->get_adr_type(ni)->isa_oopptr();
1246 Node* result = step_through_mergemem(nmm, ni, tinst);
1247 if (result == nmm->base_memory()) {
1248 // Didn't find instance memory, search through general slice recursively.
1249 result = nmm->memory_at(igvn->C->get_general_index(ni));
1250 result = find_inst_mem(result, ni, orig_phis, igvn);
1251 if (_compile->failing()) {
1252 return;
1253 }
1254 nmm->set_memory_at(ni, result);
1255 }
1256 }
1257 igvn->hash_insert(nmm);
1258 record_for_optimizer(nmm);
1260 // Propagate new memory slices to following MergeMem nodes.
1261 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1262 Node *use = n->fast_out(i);
1263 if (use->is_Call()) {
1264 CallNode* in = use->as_Call();
1265 if (in->proj_out(TypeFunc::Memory) != NULL) {
1266 Node* m = in->proj_out(TypeFunc::Memory);
1267 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
1268 Node* mm = m->fast_out(j);
1269 if (mm->is_MergeMem()) {
1270 mergemem_worklist.append_if_missing(mm);
1271 }
1272 }
1273 }
1274 if (use->is_Allocate()) {
1275 use = use->as_Allocate()->initialization();
1276 if (use == NULL) {
1277 continue;
1278 }
1279 }
1280 }
1281 if (use->is_Initialize()) {
1282 InitializeNode* in = use->as_Initialize();
1283 if (in->proj_out(TypeFunc::Memory) != NULL) {
1284 Node* m = in->proj_out(TypeFunc::Memory);
1285 for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
1286 Node* mm = m->fast_out(j);
1287 if (mm->is_MergeMem()) {
1288 mergemem_worklist.append_if_missing(mm);
1289 }
1290 }
1291 }
1292 }
1293 }
1294 }
1296 // Phase 4: Update the inputs of non-instance memory Phis and
1297 // the Memory input of memnodes
1298 // First update the inputs of any non-instance Phi's from
1299 // which we split out an instance Phi. Note we don't have
1300 // to recursively process Phi's encounted on the input memory
1301 // chains as is done in split_memory_phi() since they will
1302 // also be processed here.
1303 for (int j = 0; j < orig_phis.length(); j++) {
1304 PhiNode *phi = orig_phis.at(j);
1305 int alias_idx = _compile->get_alias_index(phi->adr_type());
1306 igvn->hash_delete(phi);
1307 for (uint i = 1; i < phi->req(); i++) {
1308 Node *mem = phi->in(i);
1309 Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn);
1310 if (_compile->failing()) {
1311 return;
1312 }
1313 if (mem != new_mem) {
1314 phi->set_req(i, new_mem);
1315 }
1316 }
1317 igvn->hash_insert(phi);
1318 record_for_optimizer(phi);
1319 }
1321 // Update the memory inputs of MemNodes with the value we computed
1322 // in Phase 2.
1323 for (uint i = 0; i < nodes_size(); i++) {
1324 Node *nmem = get_map(i);
1325 if (nmem != NULL) {
1326 Node *n = ptnode_adr(i)->_node;
1327 if (n != NULL && n->is_Mem()) {
1328 igvn->hash_delete(n);
1329 n->set_req(MemNode::Memory, nmem);
1330 igvn->hash_insert(n);
1331 record_for_optimizer(n);
1332 }
1333 }
1334 }
1335 }
1337 bool ConnectionGraph::has_candidates(Compile *C) {
1338 // EA brings benefits only when the code has allocations and/or locks which
1339 // are represented by ideal Macro nodes.
1340 int cnt = C->macro_count();
1341 for( int i=0; i < cnt; i++ ) {
1342 Node *n = C->macro_node(i);
1343 if ( n->is_Allocate() )
1344 return true;
1345 if( n->is_Lock() ) {
1346 Node* obj = n->as_Lock()->obj_node()->uncast();
1347 if( !(obj->is_Parm() || obj->is_Con()) )
1348 return true;
1349 }
1350 }
1351 return false;
1352 }
1354 bool ConnectionGraph::compute_escape() {
1355 Compile* C = _compile;
1357 // 1. Populate Connection Graph (CG) with Ideal nodes.
1359 Unique_Node_List worklist_init;
1360 worklist_init.map(C->unique(), NULL); // preallocate space
1362 // Initialize worklist
1363 if (C->root() != NULL) {
1364 worklist_init.push(C->root());
1365 }
1367 GrowableArray<int> cg_worklist;
1368 PhaseGVN* igvn = C->initial_gvn();
1369 bool has_allocations = false;
1371 // Push all useful nodes onto CG list and set their type.
1372 for( uint next = 0; next < worklist_init.size(); ++next ) {
1373 Node* n = worklist_init.at(next);
1374 record_for_escape_analysis(n, igvn);
1375 // Only allocations and java static calls results are checked
1376 // for an escape status. See process_call_result() below.
1377 if (n->is_Allocate() || n->is_CallStaticJava() &&
1378 ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) {
1379 has_allocations = true;
1380 }
1381 if(n->is_AddP())
1382 cg_worklist.append(n->_idx);
1383 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1384 Node* m = n->fast_out(i); // Get user
1385 worklist_init.push(m);
1386 }
1387 }
1389 if (!has_allocations) {
1390 _collecting = false;
1391 return false; // Nothing to do.
1392 }
1394 // 2. First pass to create simple CG edges (doesn't require to walk CG).
1395 uint delayed_size = _delayed_worklist.size();
1396 for( uint next = 0; next < delayed_size; ++next ) {
1397 Node* n = _delayed_worklist.at(next);
1398 build_connection_graph(n, igvn);
1399 }
1401 // 3. Pass to create fields edges (Allocate -F-> AddP).
1402 uint cg_length = cg_worklist.length();
1403 for( uint next = 0; next < cg_length; ++next ) {
1404 int ni = cg_worklist.at(next);
1405 build_connection_graph(ptnode_adr(ni)->_node, igvn);
1406 }
1408 cg_worklist.clear();
1409 cg_worklist.append(_phantom_object);
1411 // 4. Build Connection Graph which need
1412 // to walk the connection graph.
1413 for (uint ni = 0; ni < nodes_size(); ni++) {
1414 PointsToNode* ptn = ptnode_adr(ni);
1415 Node *n = ptn->_node;
1416 if (n != NULL) { // Call, AddP, LoadP, StoreP
1417 build_connection_graph(n, igvn);
1418 if (ptn->node_type() != PointsToNode::UnknownType)
1419 cg_worklist.append(n->_idx); // Collect CG nodes
1420 }
1421 }
1423 VectorSet ptset(Thread::current()->resource_area());
1424 GrowableArray<uint> deferred_edges;
1425 VectorSet visited(Thread::current()->resource_area());
1427 // 5. Remove deferred edges from the graph and collect
1428 // information needed for type splitting.
1429 cg_length = cg_worklist.length();
1430 for( uint next = 0; next < cg_length; ++next ) {
1431 int ni = cg_worklist.at(next);
1432 PointsToNode* ptn = ptnode_adr(ni);
1433 PointsToNode::NodeType nt = ptn->node_type();
1434 if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) {
1435 remove_deferred(ni, &deferred_edges, &visited);
1436 Node *n = ptn->_node;
1437 if (n->is_AddP()) {
1438 // Search for objects which are not scalar replaceable.
1439 // Mark their escape state as ArgEscape to propagate the state
1440 // to referenced objects.
1441 // Note: currently there are no difference in compiler optimizations
1442 // for ArgEscape objects and NoEscape objects which are not
1443 // scalar replaceable.
1445 int offset = ptn->offset();
1446 Node *base = get_addp_base(n);
1447 ptset.Clear();
1448 PointsTo(ptset, base, igvn);
1449 int ptset_size = ptset.Size();
1451 // Check if a field's initializing value is recorded and add
1452 // a corresponding NULL field's value if it is not recorded.
1453 // Connection Graph does not record a default initialization by NULL
1454 // captured by Initialize node.
1455 //
1456 // Note: it will disable scalar replacement in some cases:
1457 //
1458 // Point p[] = new Point[1];
1459 // p[0] = new Point(); // Will be not scalar replaced
1460 //
1461 // but it will save us from incorrect optimizations in next cases:
1462 //
1463 // Point p[] = new Point[1];
1464 // if ( x ) p[0] = new Point(); // Will be not scalar replaced
1465 //
1466 // Without a control flow analysis we can't distinguish above cases.
1467 //
1468 if (offset != Type::OffsetBot && ptset_size == 1) {
1469 uint elem = ptset.getelem(); // Allocation node's index
1470 // It does not matter if it is not Allocation node since
1471 // only non-escaping allocations are scalar replaced.
1472 if (ptnode_adr(elem)->_node->is_Allocate() &&
1473 ptnode_adr(elem)->escape_state() == PointsToNode::NoEscape) {
1474 AllocateNode* alloc = ptnode_adr(elem)->_node->as_Allocate();
1475 InitializeNode* ini = alloc->initialization();
1476 Node* value = NULL;
1477 if (ini != NULL) {
1478 BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT;
1479 Node* store = ini->find_captured_store(offset, type2aelembytes(ft), igvn);
1480 if (store != NULL && store->is_Store())
1481 value = store->in(MemNode::ValueIn);
1482 }
1483 if (value == NULL || value != ptnode_adr(value->_idx)->_node) {
1484 // A field's initializing value was not recorded. Add NULL.
1485 uint null_idx = UseCompressedOops ? _noop_null : _oop_null;
1486 add_pointsto_edge(ni, null_idx);
1487 }
1488 }
1489 }
1491 // An object is not scalar replaceable if the field which may point
1492 // to it has unknown offset (unknown element of an array of objects).
1493 //
1494 if (offset == Type::OffsetBot) {
1495 uint e_cnt = ptn->edge_count();
1496 for (uint ei = 0; ei < e_cnt; ei++) {
1497 uint npi = ptn->edge_target(ei);
1498 set_escape_state(npi, PointsToNode::ArgEscape);
1499 ptnode_adr(npi)->_scalar_replaceable = false;
1500 }
1501 }
1503 // Currently an object is not scalar replaceable if a LoadStore node
1504 // access its field since the field value is unknown after it.
1505 //
1506 bool has_LoadStore = false;
1507 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1508 Node *use = n->fast_out(i);
1509 if (use->is_LoadStore()) {
1510 has_LoadStore = true;
1511 break;
1512 }
1513 }
1514 // An object is not scalar replaceable if the address points
1515 // to unknown field (unknown element for arrays, offset is OffsetBot).
1516 //
1517 // Or the address may point to more then one object. This may produce
1518 // the false positive result (set scalar_replaceable to false)
1519 // since the flow-insensitive escape analysis can't separate
1520 // the case when stores overwrite the field's value from the case
1521 // when stores happened on different control branches.
1522 //
1523 if (ptset_size > 1 || ptset_size != 0 &&
1524 (has_LoadStore || offset == Type::OffsetBot)) {
1525 for( VectorSetI j(&ptset); j.test(); ++j ) {
1526 set_escape_state(j.elem, PointsToNode::ArgEscape);
1527 ptnode_adr(j.elem)->_scalar_replaceable = false;
1528 }
1529 }
1530 }
1531 }
1532 }
1534 // 6. Propagate escape states.
1535 GrowableArray<int> worklist;
1536 bool has_non_escaping_obj = false;
1538 // push all GlobalEscape nodes on the worklist
1539 for( uint next = 0; next < cg_length; ++next ) {
1540 int nk = cg_worklist.at(next);
1541 if (ptnode_adr(nk)->escape_state() == PointsToNode::GlobalEscape)
1542 worklist.push(nk);
1543 }
1544 // mark all nodes reachable from GlobalEscape nodes
1545 while(worklist.length() > 0) {
1546 PointsToNode* ptn = ptnode_adr(worklist.pop());
1547 uint e_cnt = ptn->edge_count();
1548 for (uint ei = 0; ei < e_cnt; ei++) {
1549 uint npi = ptn->edge_target(ei);
1550 PointsToNode *np = ptnode_adr(npi);
1551 if (np->escape_state() < PointsToNode::GlobalEscape) {
1552 np->set_escape_state(PointsToNode::GlobalEscape);
1553 worklist.push(npi);
1554 }
1555 }
1556 }
1558 // push all ArgEscape nodes on the worklist
1559 for( uint next = 0; next < cg_length; ++next ) {
1560 int nk = cg_worklist.at(next);
1561 if (ptnode_adr(nk)->escape_state() == PointsToNode::ArgEscape)
1562 worklist.push(nk);
1563 }
1564 // mark all nodes reachable from ArgEscape nodes
1565 while(worklist.length() > 0) {
1566 PointsToNode* ptn = ptnode_adr(worklist.pop());
1567 if (ptn->node_type() == PointsToNode::JavaObject)
1568 has_non_escaping_obj = true; // Non GlobalEscape
1569 uint e_cnt = ptn->edge_count();
1570 for (uint ei = 0; ei < e_cnt; ei++) {
1571 uint npi = ptn->edge_target(ei);
1572 PointsToNode *np = ptnode_adr(npi);
1573 if (np->escape_state() < PointsToNode::ArgEscape) {
1574 np->set_escape_state(PointsToNode::ArgEscape);
1575 worklist.push(npi);
1576 }
1577 }
1578 }
1580 GrowableArray<Node*> alloc_worklist;
1582 // push all NoEscape nodes on the worklist
1583 for( uint next = 0; next < cg_length; ++next ) {
1584 int nk = cg_worklist.at(next);
1585 if (ptnode_adr(nk)->escape_state() == PointsToNode::NoEscape)
1586 worklist.push(nk);
1587 }
1588 // mark all nodes reachable from NoEscape nodes
1589 while(worklist.length() > 0) {
1590 PointsToNode* ptn = ptnode_adr(worklist.pop());
1591 if (ptn->node_type() == PointsToNode::JavaObject)
1592 has_non_escaping_obj = true; // Non GlobalEscape
1593 Node* n = ptn->_node;
1594 if (n->is_Allocate() && ptn->_scalar_replaceable ) {
1595 // Push scalar replaceable allocations on alloc_worklist
1596 // for processing in split_unique_types().
1597 alloc_worklist.append(n);
1598 }
1599 uint e_cnt = ptn->edge_count();
1600 for (uint ei = 0; ei < e_cnt; ei++) {
1601 uint npi = ptn->edge_target(ei);
1602 PointsToNode *np = ptnode_adr(npi);
1603 if (np->escape_state() < PointsToNode::NoEscape) {
1604 np->set_escape_state(PointsToNode::NoEscape);
1605 worklist.push(npi);
1606 }
1607 }
1608 }
1610 _collecting = false;
1611 assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build");
1613 bool has_scalar_replaceable_candidates = alloc_worklist.length() > 0;
1614 if ( has_scalar_replaceable_candidates &&
1615 C->AliasLevel() >= 3 && EliminateAllocations ) {
1617 // Now use the escape information to create unique types for
1618 // scalar replaceable objects.
1619 split_unique_types(alloc_worklist);
1621 if (C->failing()) return false;
1623 // Clean up after split unique types.
1624 ResourceMark rm;
1625 PhaseRemoveUseless pru(C->initial_gvn(), C->for_igvn());
1627 C->print_method("After Escape Analysis", 2);
1629 #ifdef ASSERT
1630 } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
1631 tty->print("=== No allocations eliminated for ");
1632 C->method()->print_short_name();
1633 if(!EliminateAllocations) {
1634 tty->print(" since EliminateAllocations is off ===");
1635 } else if(!has_scalar_replaceable_candidates) {
1636 tty->print(" since there are no scalar replaceable candidates ===");
1637 } else if(C->AliasLevel() < 3) {
1638 tty->print(" since AliasLevel < 3 ===");
1639 }
1640 tty->cr();
1641 #endif
1642 }
1643 return has_non_escaping_obj;
1644 }
1646 void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) {
1648 switch (call->Opcode()) {
1649 #ifdef ASSERT
1650 case Op_Allocate:
1651 case Op_AllocateArray:
1652 case Op_Lock:
1653 case Op_Unlock:
1654 assert(false, "should be done already");
1655 break;
1656 #endif
1657 case Op_CallLeafNoFP:
1658 {
1659 // Stub calls, objects do not escape but they are not scale replaceable.
1660 // Adjust escape state for outgoing arguments.
1661 const TypeTuple * d = call->tf()->domain();
1662 VectorSet ptset(Thread::current()->resource_area());
1663 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1664 const Type* at = d->field_at(i);
1665 Node *arg = call->in(i)->uncast();
1666 const Type *aat = phase->type(arg);
1667 if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr()) {
1668 assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
1669 aat->isa_ptr() != NULL, "expecting an Ptr");
1670 set_escape_state(arg->_idx, PointsToNode::ArgEscape);
1671 if (arg->is_AddP()) {
1672 //
1673 // The inline_native_clone() case when the arraycopy stub is called
1674 // after the allocation before Initialize and CheckCastPP nodes.
1675 //
1676 // Set AddP's base (Allocate) as not scalar replaceable since
1677 // pointer to the base (with offset) is passed as argument.
1678 //
1679 arg = get_addp_base(arg);
1680 }
1681 ptset.Clear();
1682 PointsTo(ptset, arg, phase);
1683 for( VectorSetI j(&ptset); j.test(); ++j ) {
1684 uint pt = j.elem;
1685 set_escape_state(pt, PointsToNode::ArgEscape);
1686 }
1687 }
1688 }
1689 break;
1690 }
1692 case Op_CallStaticJava:
1693 // For a static call, we know exactly what method is being called.
1694 // Use bytecode estimator to record the call's escape affects
1695 {
1696 ciMethod *meth = call->as_CallJava()->method();
1697 BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
1698 // fall-through if not a Java method or no analyzer information
1699 if (call_analyzer != NULL) {
1700 const TypeTuple * d = call->tf()->domain();
1701 VectorSet ptset(Thread::current()->resource_area());
1702 bool copy_dependencies = false;
1703 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1704 const Type* at = d->field_at(i);
1705 int k = i - TypeFunc::Parms;
1707 if (at->isa_oopptr() != NULL) {
1708 Node *arg = call->in(i)->uncast();
1710 bool global_escapes = false;
1711 bool fields_escapes = false;
1712 if (!call_analyzer->is_arg_stack(k)) {
1713 // The argument global escapes, mark everything it could point to
1714 set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
1715 global_escapes = true;
1716 } else {
1717 if (!call_analyzer->is_arg_local(k)) {
1718 // The argument itself doesn't escape, but any fields might
1719 fields_escapes = true;
1720 }
1721 set_escape_state(arg->_idx, PointsToNode::ArgEscape);
1722 copy_dependencies = true;
1723 }
1725 ptset.Clear();
1726 PointsTo(ptset, arg, phase);
1727 for( VectorSetI j(&ptset); j.test(); ++j ) {
1728 uint pt = j.elem;
1729 if (global_escapes) {
1730 //The argument global escapes, mark everything it could point to
1731 set_escape_state(pt, PointsToNode::GlobalEscape);
1732 } else {
1733 if (fields_escapes) {
1734 // The argument itself doesn't escape, but any fields might
1735 add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
1736 }
1737 set_escape_state(pt, PointsToNode::ArgEscape);
1738 }
1739 }
1740 }
1741 }
1742 if (copy_dependencies)
1743 call_analyzer->copy_dependencies(_compile->dependencies());
1744 break;
1745 }
1746 }
1748 default:
1749 // Fall-through here if not a Java method or no analyzer information
1750 // or some other type of call, assume the worst case: all arguments
1751 // globally escape.
1752 {
1753 // adjust escape state for outgoing arguments
1754 const TypeTuple * d = call->tf()->domain();
1755 VectorSet ptset(Thread::current()->resource_area());
1756 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1757 const Type* at = d->field_at(i);
1758 if (at->isa_oopptr() != NULL) {
1759 Node *arg = call->in(i)->uncast();
1760 set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
1761 ptset.Clear();
1762 PointsTo(ptset, arg, phase);
1763 for( VectorSetI j(&ptset); j.test(); ++j ) {
1764 uint pt = j.elem;
1765 set_escape_state(pt, PointsToNode::GlobalEscape);
1766 }
1767 }
1768 }
1769 }
1770 }
1771 }
1772 void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) {
1773 CallNode *call = resproj->in(0)->as_Call();
1774 uint call_idx = call->_idx;
1775 uint resproj_idx = resproj->_idx;
1777 switch (call->Opcode()) {
1778 case Op_Allocate:
1779 {
1780 Node *k = call->in(AllocateNode::KlassNode);
1781 const TypeKlassPtr *kt;
1782 if (k->Opcode() == Op_LoadKlass) {
1783 kt = k->as_Load()->type()->isa_klassptr();
1784 } else {
1785 // Also works for DecodeN(LoadNKlass).
1786 kt = k->as_Type()->type()->isa_klassptr();
1787 }
1788 assert(kt != NULL, "TypeKlassPtr required.");
1789 ciKlass* cik = kt->klass();
1790 ciInstanceKlass* ciik = cik->as_instance_klass();
1792 PointsToNode::EscapeState es;
1793 uint edge_to;
1794 if (cik->is_subclass_of(_compile->env()->Thread_klass()) || ciik->has_finalizer()) {
1795 es = PointsToNode::GlobalEscape;
1796 edge_to = _phantom_object; // Could not be worse
1797 } else {
1798 es = PointsToNode::NoEscape;
1799 edge_to = call_idx;
1800 }
1801 set_escape_state(call_idx, es);
1802 add_pointsto_edge(resproj_idx, edge_to);
1803 _processed.set(resproj_idx);
1804 break;
1805 }
1807 case Op_AllocateArray:
1808 {
1809 int length = call->in(AllocateNode::ALength)->find_int_con(-1);
1810 if (length < 0 || length > EliminateAllocationArraySizeLimit) {
1811 // Not scalar replaceable if the length is not constant or too big.
1812 ptnode_adr(call_idx)->_scalar_replaceable = false;
1813 }
1814 set_escape_state(call_idx, PointsToNode::NoEscape);
1815 add_pointsto_edge(resproj_idx, call_idx);
1816 _processed.set(resproj_idx);
1817 break;
1818 }
1820 case Op_CallStaticJava:
1821 // For a static call, we know exactly what method is being called.
1822 // Use bytecode estimator to record whether the call's return value escapes
1823 {
1824 bool done = true;
1825 const TypeTuple *r = call->tf()->range();
1826 const Type* ret_type = NULL;
1828 if (r->cnt() > TypeFunc::Parms)
1829 ret_type = r->field_at(TypeFunc::Parms);
1831 // Note: we use isa_ptr() instead of isa_oopptr() here because the
1832 // _multianewarray functions return a TypeRawPtr.
1833 if (ret_type == NULL || ret_type->isa_ptr() == NULL) {
1834 _processed.set(resproj_idx);
1835 break; // doesn't return a pointer type
1836 }
1837 ciMethod *meth = call->as_CallJava()->method();
1838 const TypeTuple * d = call->tf()->domain();
1839 if (meth == NULL) {
1840 // not a Java method, assume global escape
1841 set_escape_state(call_idx, PointsToNode::GlobalEscape);
1842 add_pointsto_edge(resproj_idx, _phantom_object);
1843 } else {
1844 BCEscapeAnalyzer *call_analyzer = meth->get_bcea();
1845 bool copy_dependencies = false;
1847 if (call_analyzer->is_return_allocated()) {
1848 // Returns a newly allocated unescaped object, simply
1849 // update dependency information.
1850 // Mark it as NoEscape so that objects referenced by
1851 // it's fields will be marked as NoEscape at least.
1852 set_escape_state(call_idx, PointsToNode::NoEscape);
1853 add_pointsto_edge(resproj_idx, call_idx);
1854 copy_dependencies = true;
1855 } else if (call_analyzer->is_return_local()) {
1856 // determine whether any arguments are returned
1857 set_escape_state(call_idx, PointsToNode::NoEscape);
1858 bool ret_arg = false;
1859 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1860 const Type* at = d->field_at(i);
1862 if (at->isa_oopptr() != NULL) {
1863 Node *arg = call->in(i)->uncast();
1865 if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
1866 ret_arg = true;
1867 PointsToNode *arg_esp = ptnode_adr(arg->_idx);
1868 if (arg_esp->node_type() == PointsToNode::UnknownType)
1869 done = false;
1870 else if (arg_esp->node_type() == PointsToNode::JavaObject)
1871 add_pointsto_edge(resproj_idx, arg->_idx);
1872 else
1873 add_deferred_edge(resproj_idx, arg->_idx);
1874 arg_esp->_hidden_alias = true;
1875 }
1876 }
1877 }
1878 if (done && !ret_arg) {
1879 // Returns unknown object.
1880 set_escape_state(call_idx, PointsToNode::GlobalEscape);
1881 add_pointsto_edge(resproj_idx, _phantom_object);
1882 }
1883 copy_dependencies = true;
1884 } else {
1885 set_escape_state(call_idx, PointsToNode::GlobalEscape);
1886 add_pointsto_edge(resproj_idx, _phantom_object);
1887 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
1888 const Type* at = d->field_at(i);
1889 if (at->isa_oopptr() != NULL) {
1890 Node *arg = call->in(i)->uncast();
1891 PointsToNode *arg_esp = ptnode_adr(arg->_idx);
1892 arg_esp->_hidden_alias = true;
1893 }
1894 }
1895 }
1896 if (copy_dependencies)
1897 call_analyzer->copy_dependencies(_compile->dependencies());
1898 }
1899 if (done)
1900 _processed.set(resproj_idx);
1901 break;
1902 }
1904 default:
1905 // Some other type of call, assume the worst case that the
1906 // returned value, if any, globally escapes.
1907 {
1908 const TypeTuple *r = call->tf()->range();
1909 if (r->cnt() > TypeFunc::Parms) {
1910 const Type* ret_type = r->field_at(TypeFunc::Parms);
1912 // Note: we use isa_ptr() instead of isa_oopptr() here because the
1913 // _multianewarray functions return a TypeRawPtr.
1914 if (ret_type->isa_ptr() != NULL) {
1915 set_escape_state(call_idx, PointsToNode::GlobalEscape);
1916 add_pointsto_edge(resproj_idx, _phantom_object);
1917 }
1918 }
1919 _processed.set(resproj_idx);
1920 }
1921 }
1922 }
1924 // Populate Connection Graph with Ideal nodes and create simple
1925 // connection graph edges (do not need to check the node_type of inputs
1926 // or to call PointsTo() to walk the connection graph).
1927 void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) {
1928 if (_processed.test(n->_idx))
1929 return; // No need to redefine node's state.
1931 if (n->is_Call()) {
1932 // Arguments to allocation and locking don't escape.
1933 if (n->is_Allocate()) {
1934 add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true);
1935 record_for_optimizer(n);
1936 } else if (n->is_Lock() || n->is_Unlock()) {
1937 // Put Lock and Unlock nodes on IGVN worklist to process them during
1938 // the first IGVN optimization when escape information is still available.
1939 record_for_optimizer(n);
1940 _processed.set(n->_idx);
1941 } else {
1942 // Have to process call's arguments first.
1943 PointsToNode::NodeType nt = PointsToNode::UnknownType;
1945 // Check if a call returns an object.
1946 const TypeTuple *r = n->as_Call()->tf()->range();
1947 if (n->is_CallStaticJava() && r->cnt() > TypeFunc::Parms &&
1948 n->as_Call()->proj_out(TypeFunc::Parms) != NULL) {
1949 // Note: use isa_ptr() instead of isa_oopptr() here because
1950 // the _multianewarray functions return a TypeRawPtr.
1951 if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
1952 nt = PointsToNode::JavaObject;
1953 }
1954 }
1955 add_node(n, nt, PointsToNode::UnknownEscape, false);
1956 }
1957 return;
1958 }
1960 // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
1961 // ThreadLocal has RawPrt type.
1962 switch (n->Opcode()) {
1963 case Op_AddP:
1964 {
1965 add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false);
1966 break;
1967 }
1968 case Op_CastX2P:
1969 { // "Unsafe" memory access.
1970 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
1971 break;
1972 }
1973 case Op_CastPP:
1974 case Op_CheckCastPP:
1975 case Op_EncodeP:
1976 case Op_DecodeN:
1977 {
1978 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
1979 int ti = n->in(1)->_idx;
1980 PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
1981 if (nt == PointsToNode::UnknownType) {
1982 _delayed_worklist.push(n); // Process it later.
1983 break;
1984 } else if (nt == PointsToNode::JavaObject) {
1985 add_pointsto_edge(n->_idx, ti);
1986 } else {
1987 add_deferred_edge(n->_idx, ti);
1988 }
1989 _processed.set(n->_idx);
1990 break;
1991 }
1992 case Op_ConP:
1993 {
1994 // assume all pointer constants globally escape except for null
1995 PointsToNode::EscapeState es;
1996 if (phase->type(n) == TypePtr::NULL_PTR)
1997 es = PointsToNode::NoEscape;
1998 else
1999 es = PointsToNode::GlobalEscape;
2001 add_node(n, PointsToNode::JavaObject, es, true);
2002 break;
2003 }
2004 case Op_ConN:
2005 {
2006 // assume all narrow oop constants globally escape except for null
2007 PointsToNode::EscapeState es;
2008 if (phase->type(n) == TypeNarrowOop::NULL_PTR)
2009 es = PointsToNode::NoEscape;
2010 else
2011 es = PointsToNode::GlobalEscape;
2013 add_node(n, PointsToNode::JavaObject, es, true);
2014 break;
2015 }
2016 case Op_CreateEx:
2017 {
2018 // assume that all exception objects globally escape
2019 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
2020 break;
2021 }
2022 case Op_LoadKlass:
2023 case Op_LoadNKlass:
2024 {
2025 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
2026 break;
2027 }
2028 case Op_LoadP:
2029 case Op_LoadN:
2030 {
2031 const Type *t = phase->type(n);
2032 if (t->make_ptr() == NULL) {
2033 _processed.set(n->_idx);
2034 return;
2035 }
2036 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
2037 break;
2038 }
2039 case Op_Parm:
2040 {
2041 _processed.set(n->_idx); // No need to redefine it state.
2042 uint con = n->as_Proj()->_con;
2043 if (con < TypeFunc::Parms)
2044 return;
2045 const Type *t = n->in(0)->as_Start()->_domain->field_at(con);
2046 if (t->isa_ptr() == NULL)
2047 return;
2048 // We have to assume all input parameters globally escape
2049 // (Note: passing 'false' since _processed is already set).
2050 add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false);
2051 break;
2052 }
2053 case Op_Phi:
2054 {
2055 const Type *t = n->as_Phi()->type();
2056 if (t->make_ptr() == NULL) {
2057 // nothing to do if not an oop or narrow oop
2058 _processed.set(n->_idx);
2059 return;
2060 }
2061 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
2062 uint i;
2063 for (i = 1; i < n->req() ; i++) {
2064 Node* in = n->in(i);
2065 if (in == NULL)
2066 continue; // ignore NULL
2067 in = in->uncast();
2068 if (in->is_top() || in == n)
2069 continue; // ignore top or inputs which go back this node
2070 int ti = in->_idx;
2071 PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
2072 if (nt == PointsToNode::UnknownType) {
2073 break;
2074 } else if (nt == PointsToNode::JavaObject) {
2075 add_pointsto_edge(n->_idx, ti);
2076 } else {
2077 add_deferred_edge(n->_idx, ti);
2078 }
2079 }
2080 if (i >= n->req())
2081 _processed.set(n->_idx);
2082 else
2083 _delayed_worklist.push(n);
2084 break;
2085 }
2086 case Op_Proj:
2087 {
2088 // we are only interested in the result projection from a call
2089 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
2090 add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
2091 process_call_result(n->as_Proj(), phase);
2092 if (!_processed.test(n->_idx)) {
2093 // The call's result may need to be processed later if the call
2094 // returns it's argument and the argument is not processed yet.
2095 _delayed_worklist.push(n);
2096 }
2097 } else {
2098 _processed.set(n->_idx);
2099 }
2100 break;
2101 }
2102 case Op_Return:
2103 {
2104 if( n->req() > TypeFunc::Parms &&
2105 phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
2106 // Treat Return value as LocalVar with GlobalEscape escape state.
2107 add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false);
2108 int ti = n->in(TypeFunc::Parms)->_idx;
2109 PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
2110 if (nt == PointsToNode::UnknownType) {
2111 _delayed_worklist.push(n); // Process it later.
2112 break;
2113 } else if (nt == PointsToNode::JavaObject) {
2114 add_pointsto_edge(n->_idx, ti);
2115 } else {
2116 add_deferred_edge(n->_idx, ti);
2117 }
2118 }
2119 _processed.set(n->_idx);
2120 break;
2121 }
2122 case Op_StoreP:
2123 case Op_StoreN:
2124 {
2125 const Type *adr_type = phase->type(n->in(MemNode::Address));
2126 adr_type = adr_type->make_ptr();
2127 if (adr_type->isa_oopptr()) {
2128 add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
2129 } else {
2130 Node* adr = n->in(MemNode::Address);
2131 if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL &&
2132 adr->in(AddPNode::Address)->is_Proj() &&
2133 adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
2134 add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
2135 // We are computing a raw address for a store captured
2136 // by an Initialize compute an appropriate address type.
2137 int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
2138 assert(offs != Type::OffsetBot, "offset must be a constant");
2139 } else {
2140 _processed.set(n->_idx);
2141 return;
2142 }
2143 }
2144 break;
2145 }
2146 case Op_StorePConditional:
2147 case Op_CompareAndSwapP:
2148 case Op_CompareAndSwapN:
2149 {
2150 const Type *adr_type = phase->type(n->in(MemNode::Address));
2151 adr_type = adr_type->make_ptr();
2152 if (adr_type->isa_oopptr()) {
2153 add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
2154 } else {
2155 _processed.set(n->_idx);
2156 return;
2157 }
2158 break;
2159 }
2160 case Op_ThreadLocal:
2161 {
2162 add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true);
2163 break;
2164 }
2165 default:
2166 ;
2167 // nothing to do
2168 }
2169 return;
2170 }
2172 void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) {
2173 uint n_idx = n->_idx;
2175 // Don't set processed bit for AddP, LoadP, StoreP since
2176 // they may need more then one pass to process.
2177 if (_processed.test(n_idx))
2178 return; // No need to redefine node's state.
2180 if (n->is_Call()) {
2181 CallNode *call = n->as_Call();
2182 process_call_arguments(call, phase);
2183 _processed.set(n_idx);
2184 return;
2185 }
2187 switch (n->Opcode()) {
2188 case Op_AddP:
2189 {
2190 Node *base = get_addp_base(n);
2191 // Create a field edge to this node from everything base could point to.
2192 VectorSet ptset(Thread::current()->resource_area());
2193 PointsTo(ptset, base, phase);
2194 for( VectorSetI i(&ptset); i.test(); ++i ) {
2195 uint pt = i.elem;
2196 add_field_edge(pt, n_idx, address_offset(n, phase));
2197 }
2198 break;
2199 }
2200 case Op_CastX2P:
2201 {
2202 assert(false, "Op_CastX2P");
2203 break;
2204 }
2205 case Op_CastPP:
2206 case Op_CheckCastPP:
2207 case Op_EncodeP:
2208 case Op_DecodeN:
2209 {
2210 int ti = n->in(1)->_idx;
2211 if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
2212 add_pointsto_edge(n_idx, ti);
2213 } else {
2214 add_deferred_edge(n_idx, ti);
2215 }
2216 _processed.set(n_idx);
2217 break;
2218 }
2219 case Op_ConP:
2220 {
2221 assert(false, "Op_ConP");
2222 break;
2223 }
2224 case Op_ConN:
2225 {
2226 assert(false, "Op_ConN");
2227 break;
2228 }
2229 case Op_CreateEx:
2230 {
2231 assert(false, "Op_CreateEx");
2232 break;
2233 }
2234 case Op_LoadKlass:
2235 case Op_LoadNKlass:
2236 {
2237 assert(false, "Op_LoadKlass");
2238 break;
2239 }
2240 case Op_LoadP:
2241 case Op_LoadN:
2242 {
2243 const Type *t = phase->type(n);
2244 #ifdef ASSERT
2245 if (t->make_ptr() == NULL)
2246 assert(false, "Op_LoadP");
2247 #endif
2249 Node* adr = n->in(MemNode::Address)->uncast();
2250 const Type *adr_type = phase->type(adr);
2251 Node* adr_base;
2252 if (adr->is_AddP()) {
2253 adr_base = get_addp_base(adr);
2254 } else {
2255 adr_base = adr;
2256 }
2258 // For everything "adr_base" could point to, create a deferred edge from
2259 // this node to each field with the same offset.
2260 VectorSet ptset(Thread::current()->resource_area());
2261 PointsTo(ptset, adr_base, phase);
2262 int offset = address_offset(adr, phase);
2263 for( VectorSetI i(&ptset); i.test(); ++i ) {
2264 uint pt = i.elem;
2265 add_deferred_edge_to_fields(n_idx, pt, offset);
2266 }
2267 break;
2268 }
2269 case Op_Parm:
2270 {
2271 assert(false, "Op_Parm");
2272 break;
2273 }
2274 case Op_Phi:
2275 {
2276 #ifdef ASSERT
2277 const Type *t = n->as_Phi()->type();
2278 if (t->make_ptr() == NULL)
2279 assert(false, "Op_Phi");
2280 #endif
2281 for (uint i = 1; i < n->req() ; i++) {
2282 Node* in = n->in(i);
2283 if (in == NULL)
2284 continue; // ignore NULL
2285 in = in->uncast();
2286 if (in->is_top() || in == n)
2287 continue; // ignore top or inputs which go back this node
2288 int ti = in->_idx;
2289 PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
2290 assert(nt != PointsToNode::UnknownType, "all nodes should be known");
2291 if (nt == PointsToNode::JavaObject) {
2292 add_pointsto_edge(n_idx, ti);
2293 } else {
2294 add_deferred_edge(n_idx, ti);
2295 }
2296 }
2297 _processed.set(n_idx);
2298 break;
2299 }
2300 case Op_Proj:
2301 {
2302 // we are only interested in the result projection from a call
2303 if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
2304 process_call_result(n->as_Proj(), phase);
2305 assert(_processed.test(n_idx), "all call results should be processed");
2306 } else {
2307 assert(false, "Op_Proj");
2308 }
2309 break;
2310 }
2311 case Op_Return:
2312 {
2313 #ifdef ASSERT
2314 if( n->req() <= TypeFunc::Parms ||
2315 !phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
2316 assert(false, "Op_Return");
2317 }
2318 #endif
2319 int ti = n->in(TypeFunc::Parms)->_idx;
2320 if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
2321 add_pointsto_edge(n_idx, ti);
2322 } else {
2323 add_deferred_edge(n_idx, ti);
2324 }
2325 _processed.set(n_idx);
2326 break;
2327 }
2328 case Op_StoreP:
2329 case Op_StoreN:
2330 case Op_StorePConditional:
2331 case Op_CompareAndSwapP:
2332 case Op_CompareAndSwapN:
2333 {
2334 Node *adr = n->in(MemNode::Address);
2335 const Type *adr_type = phase->type(adr)->make_ptr();
2336 #ifdef ASSERT
2337 if (!adr_type->isa_oopptr())
2338 assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP");
2339 #endif
2341 assert(adr->is_AddP(), "expecting an AddP");
2342 Node *adr_base = get_addp_base(adr);
2343 Node *val = n->in(MemNode::ValueIn)->uncast();
2344 // For everything "adr_base" could point to, create a deferred edge
2345 // to "val" from each field with the same offset.
2346 VectorSet ptset(Thread::current()->resource_area());
2347 PointsTo(ptset, adr_base, phase);
2348 for( VectorSetI i(&ptset); i.test(); ++i ) {
2349 uint pt = i.elem;
2350 add_edge_from_fields(pt, val->_idx, address_offset(adr, phase));
2351 }
2352 break;
2353 }
2354 case Op_ThreadLocal:
2355 {
2356 assert(false, "Op_ThreadLocal");
2357 break;
2358 }
2359 default:
2360 ;
2361 // nothing to do
2362 }
2363 }
2365 #ifndef PRODUCT
2366 void ConnectionGraph::dump() {
2367 PhaseGVN *igvn = _compile->initial_gvn();
2368 bool first = true;
2370 uint size = nodes_size();
2371 for (uint ni = 0; ni < size; ni++) {
2372 PointsToNode *ptn = ptnode_adr(ni);
2373 PointsToNode::NodeType ptn_type = ptn->node_type();
2375 if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL)
2376 continue;
2377 PointsToNode::EscapeState es = escape_state(ptn->_node, igvn);
2378 if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) {
2379 if (first) {
2380 tty->cr();
2381 tty->print("======== Connection graph for ");
2382 _compile->method()->print_short_name();
2383 tty->cr();
2384 first = false;
2385 }
2386 tty->print("%6d ", ni);
2387 ptn->dump();
2388 // Print all locals which reference this allocation
2389 for (uint li = ni; li < size; li++) {
2390 PointsToNode *ptn_loc = ptnode_adr(li);
2391 PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type();
2392 if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL &&
2393 ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) {
2394 ptnode_adr(li)->dump(false);
2395 }
2396 }
2397 if (Verbose) {
2398 // Print all fields which reference this allocation
2399 for (uint i = 0; i < ptn->edge_count(); i++) {
2400 uint ei = ptn->edge_target(i);
2401 ptnode_adr(ei)->dump(false);
2402 }
2403 }
2404 tty->cr();
2405 }
2406 }
2407 }
2408 #endif