src/share/vm/opto/escape.cpp

Wed, 03 Dec 2008 13:41:37 -0800

author
kvn
date
Wed, 03 Dec 2008 13:41:37 -0800
changeset 895
424f9bfe6b96
parent 742
892493c3d862
child 1019
49a36a80b0c7
permissions
-rw-r--r--

6775880: EA +DeoptimizeALot: assert(mon_info->owner()->is_locked(),"object must be locked now")
Summary: Create new "eliminated" BoxLock node for monitor debug info when corresponding locks are eliminated.
Reviewed-by: never

     1 /*
     2  * Copyright 2005-2008 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
    21  * have any questions.
    22  *
    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     assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal ||
   443            base->Opcode() == Op_CastX2P || base->is_DecodeN() ||
   444            (base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) ||
   445            (base->is_Proj() && base->in(0)->is_Allocate()), "sanity");
   446   }
   447   return base;
   448 }
   450 static Node* find_second_addp(Node* addp, Node* n) {
   451   assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
   453   Node* addp2 = addp->raw_out(0);
   454   if (addp->outcnt() == 1 && addp2->is_AddP() &&
   455       addp2->in(AddPNode::Base) == n &&
   456       addp2->in(AddPNode::Address) == addp) {
   458     assert(addp->in(AddPNode::Base) == n, "expecting the same base");
   459     //
   460     // Find array's offset to push it on worklist first and
   461     // as result process an array's element offset first (pushed second)
   462     // to avoid CastPP for the array's offset.
   463     // Otherwise the inserted CastPP (LocalVar) will point to what
   464     // the AddP (Field) points to. Which would be wrong since
   465     // the algorithm expects the CastPP has the same point as
   466     // as AddP's base CheckCastPP (LocalVar).
   467     //
   468     //    ArrayAllocation
   469     //     |
   470     //    CheckCastPP
   471     //     |
   472     //    memProj (from ArrayAllocation CheckCastPP)
   473     //     |  ||
   474     //     |  ||   Int (element index)
   475     //     |  ||    |   ConI (log(element size))
   476     //     |  ||    |   /
   477     //     |  ||   LShift
   478     //     |  ||  /
   479     //     |  AddP (array's element offset)
   480     //     |  |
   481     //     |  | ConI (array's offset: #12(32-bits) or #24(64-bits))
   482     //     | / /
   483     //     AddP (array's offset)
   484     //      |
   485     //     Load/Store (memory operation on array's element)
   486     //
   487     return addp2;
   488   }
   489   return NULL;
   490 }
   492 //
   493 // Adjust the type and inputs of an AddP which computes the
   494 // address of a field of an instance
   495 //
   496 bool ConnectionGraph::split_AddP(Node *addp, Node *base,  PhaseGVN  *igvn) {
   497   const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
   498   assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
   499   const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
   500   if (t == NULL) {
   501     // We are computing a raw address for a store captured by an Initialize
   502     // compute an appropriate address type (cases #3 and #5).
   503     assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
   504     assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
   505     intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
   506     assert(offs != Type::OffsetBot, "offset must be a constant");
   507     t = base_t->add_offset(offs)->is_oopptr();
   508   }
   509   int inst_id =  base_t->instance_id();
   510   assert(!t->is_known_instance() || t->instance_id() == inst_id,
   511                              "old type must be non-instance or match new type");
   513   // The type 't' could be subclass of 'base_t'.
   514   // As result t->offset() could be large then base_t's size and it will
   515   // cause the failure in add_offset() with narrow oops since TypeOopPtr()
   516   // constructor verifies correctness of the offset.
   517   //
   518   // It could happend on subclass's branch (from the type profiling
   519   // inlining) which was not eliminated during parsing since the exactness
   520   // of the allocation type was not propagated to the subclass type check.
   521   //
   522   // Do nothing for such AddP node and don't process its users since
   523   // this code branch will go away.
   524   //
   525   if (!t->is_known_instance() &&
   526       !t->klass()->equals(base_t->klass()) &&
   527       t->klass()->is_subtype_of(base_t->klass())) {
   528      return false; // bail out
   529   }
   531   const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
   532   // Do NOT remove the next call: ensure an new alias index is allocated
   533   // for the instance type
   534   int alias_idx = _compile->get_alias_index(tinst);
   535   igvn->set_type(addp, tinst);
   536   // record the allocation in the node map
   537   set_map(addp->_idx, get_map(base->_idx));
   539   // Set addp's Base and Address to 'base'.
   540   Node *abase = addp->in(AddPNode::Base);
   541   Node *adr   = addp->in(AddPNode::Address);
   542   if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
   543       adr->in(0)->_idx == (uint)inst_id) {
   544     // Skip AddP cases #3 and #5.
   545   } else {
   546     assert(!abase->is_top(), "sanity"); // AddP case #3
   547     if (abase != base) {
   548       igvn->hash_delete(addp);
   549       addp->set_req(AddPNode::Base, base);
   550       if (abase == adr) {
   551         addp->set_req(AddPNode::Address, base);
   552       } else {
   553         // AddP case #4 (adr is array's element offset AddP node)
   554 #ifdef ASSERT
   555         const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
   556         assert(adr->is_AddP() && atype != NULL &&
   557                atype->instance_id() == inst_id, "array's element offset should be processed first");
   558 #endif
   559       }
   560       igvn->hash_insert(addp);
   561     }
   562   }
   563   // Put on IGVN worklist since at least addp's type was changed above.
   564   record_for_optimizer(addp);
   565   return true;
   566 }
   568 //
   569 // Create a new version of orig_phi if necessary. Returns either the newly
   570 // created phi or an existing phi.  Sets create_new to indicate wheter  a new
   571 // phi was created.  Cache the last newly created phi in the node map.
   572 //
   573 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn, bool &new_created) {
   574   Compile *C = _compile;
   575   new_created = false;
   576   int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
   577   // nothing to do if orig_phi is bottom memory or matches alias_idx
   578   if (phi_alias_idx == alias_idx) {
   579     return orig_phi;
   580   }
   581   // have we already created a Phi for this alias index?
   582   PhiNode *result = get_map_phi(orig_phi->_idx);
   583   if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
   584     return result;
   585   }
   586   if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) {
   587     if (C->do_escape_analysis() == true && !C->failing()) {
   588       // Retry compilation without escape analysis.
   589       // If this is the first failure, the sentinel string will "stick"
   590       // to the Compile object, and the C2Compiler will see it and retry.
   591       C->record_failure(C2Compiler::retry_no_escape_analysis());
   592     }
   593     return NULL;
   594   }
   595   orig_phi_worklist.append_if_missing(orig_phi);
   596   const TypePtr *atype = C->get_adr_type(alias_idx);
   597   result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
   598   set_map_phi(orig_phi->_idx, result);
   599   igvn->set_type(result, result->bottom_type());
   600   record_for_optimizer(result);
   601   new_created = true;
   602   return result;
   603 }
   605 //
   606 // Return a new version  of Memory Phi "orig_phi" with the inputs having the
   607 // specified alias index.
   608 //
   609 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn) {
   611   assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
   612   Compile *C = _compile;
   613   bool new_phi_created;
   614   PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created);
   615   if (!new_phi_created) {
   616     return result;
   617   }
   619   GrowableArray<PhiNode *>  phi_list;
   620   GrowableArray<uint>  cur_input;
   622   PhiNode *phi = orig_phi;
   623   uint idx = 1;
   624   bool finished = false;
   625   while(!finished) {
   626     while (idx < phi->req()) {
   627       Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn);
   628       if (mem != NULL && mem->is_Phi()) {
   629         PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created);
   630         if (new_phi_created) {
   631           // found an phi for which we created a new split, push current one on worklist and begin
   632           // processing new one
   633           phi_list.push(phi);
   634           cur_input.push(idx);
   635           phi = mem->as_Phi();
   636           result = newphi;
   637           idx = 1;
   638           continue;
   639         } else {
   640           mem = newphi;
   641         }
   642       }
   643       if (C->failing()) {
   644         return NULL;
   645       }
   646       result->set_req(idx++, mem);
   647     }
   648 #ifdef ASSERT
   649     // verify that the new Phi has an input for each input of the original
   650     assert( phi->req() == result->req(), "must have same number of inputs.");
   651     assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
   652 #endif
   653     // Check if all new phi's inputs have specified alias index.
   654     // Otherwise use old phi.
   655     for (uint i = 1; i < phi->req(); i++) {
   656       Node* in = result->in(i);
   657       assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
   658     }
   659     // we have finished processing a Phi, see if there are any more to do
   660     finished = (phi_list.length() == 0 );
   661     if (!finished) {
   662       phi = phi_list.pop();
   663       idx = cur_input.pop();
   664       PhiNode *prev_result = get_map_phi(phi->_idx);
   665       prev_result->set_req(idx++, result);
   666       result = prev_result;
   667     }
   668   }
   669   return result;
   670 }
   673 //
   674 // The next methods are derived from methods in MemNode.
   675 //
   676 static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *tinst) {
   677   Node *mem = mmem;
   678   // TypeInstPtr::NOTNULL+any is an OOP with unknown offset - generally
   679   // means an array I have not precisely typed yet.  Do not do any
   680   // alias stuff with it any time soon.
   681   if( tinst->base() != Type::AnyPtr &&
   682       !(tinst->klass()->is_java_lang_Object() &&
   683         tinst->offset() == Type::OffsetBot) ) {
   684     mem = mmem->memory_at(alias_idx);
   685     // Update input if it is progress over what we have now
   686   }
   687   return mem;
   688 }
   690 //
   691 // Search memory chain of "mem" to find a MemNode whose address
   692 // is the specified alias index.
   693 //
   694 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *>  &orig_phis, PhaseGVN *phase) {
   695   if (orig_mem == NULL)
   696     return orig_mem;
   697   Compile* C = phase->C;
   698   const TypeOopPtr *tinst = C->get_adr_type(alias_idx)->isa_oopptr();
   699   bool is_instance = (tinst != NULL) && tinst->is_known_instance();
   700   Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
   701   Node *prev = NULL;
   702   Node *result = orig_mem;
   703   while (prev != result) {
   704     prev = result;
   705     if (result == start_mem)
   706       break;  // hit one of our sentinals
   707     if (result->is_Mem()) {
   708       const Type *at = phase->type(result->in(MemNode::Address));
   709       if (at != Type::TOP) {
   710         assert (at->isa_ptr() != NULL, "pointer type required.");
   711         int idx = C->get_alias_index(at->is_ptr());
   712         if (idx == alias_idx)
   713           break;
   714       }
   715       result = result->in(MemNode::Memory);
   716     }
   717     if (!is_instance)
   718       continue;  // don't search further for non-instance types
   719     // skip over a call which does not affect this memory slice
   720     if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
   721       Node *proj_in = result->in(0);
   722       if (proj_in->is_Allocate() && proj_in->_idx == (uint)tinst->instance_id()) {
   723         break;  // hit one of our sentinals
   724       } else if (proj_in->is_Call()) {
   725         CallNode *call = proj_in->as_Call();
   726         if (!call->may_modify(tinst, phase)) {
   727           result = call->in(TypeFunc::Memory);
   728         }
   729       } else if (proj_in->is_Initialize()) {
   730         AllocateNode* alloc = proj_in->as_Initialize()->allocation();
   731         // Stop if this is the initialization for the object instance which
   732         // which contains this memory slice, otherwise skip over it.
   733         if (alloc == NULL || alloc->_idx != (uint)tinst->instance_id()) {
   734           result = proj_in->in(TypeFunc::Memory);
   735         }
   736       } else if (proj_in->is_MemBar()) {
   737         result = proj_in->in(TypeFunc::Memory);
   738       }
   739     } else if (result->is_MergeMem()) {
   740       MergeMemNode *mmem = result->as_MergeMem();
   741       result = step_through_mergemem(mmem, alias_idx, tinst);
   742       if (result == mmem->base_memory()) {
   743         // Didn't find instance memory, search through general slice recursively.
   744         result = mmem->memory_at(C->get_general_index(alias_idx));
   745         result = find_inst_mem(result, alias_idx, orig_phis, phase);
   746         if (C->failing()) {
   747           return NULL;
   748         }
   749         mmem->set_memory_at(alias_idx, result);
   750       }
   751     } else if (result->is_Phi() &&
   752                C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
   753       Node *un = result->as_Phi()->unique_input(phase);
   754       if (un != NULL) {
   755         result = un;
   756       } else {
   757         break;
   758       }
   759     }
   760   }
   761   if (result->is_Phi()) {
   762     PhiNode *mphi = result->as_Phi();
   763     assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
   764     const TypePtr *t = mphi->adr_type();
   765     if (C->get_alias_index(t) != alias_idx) {
   766       // Create a new Phi with the specified alias index type.
   767       result = split_memory_phi(mphi, alias_idx, orig_phis, phase);
   768     } else if (!is_instance) {
   769       // Push all non-instance Phis on the orig_phis worklist to update inputs
   770       // during Phase 4 if needed.
   771       orig_phis.append_if_missing(mphi);
   772     }
   773   }
   774   // the result is either MemNode, PhiNode, InitializeNode.
   775   return result;
   776 }
   779 //
   780 //  Convert the types of unescaped object to instance types where possible,
   781 //  propagate the new type information through the graph, and update memory
   782 //  edges and MergeMem inputs to reflect the new type.
   783 //
   784 //  We start with allocations (and calls which may be allocations)  on alloc_worklist.
   785 //  The processing is done in 4 phases:
   786 //
   787 //  Phase 1:  Process possible allocations from alloc_worklist.  Create instance
   788 //            types for the CheckCastPP for allocations where possible.
   789 //            Propagate the the new types through users as follows:
   790 //               casts and Phi:  push users on alloc_worklist
   791 //               AddP:  cast Base and Address inputs to the instance type
   792 //                      push any AddP users on alloc_worklist and push any memnode
   793 //                      users onto memnode_worklist.
   794 //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
   795 //            search the Memory chain for a store with the appropriate type
   796 //            address type.  If a Phi is found, create a new version with
   797 //            the approriate memory slices from each of the Phi inputs.
   798 //            For stores, process the users as follows:
   799 //               MemNode:  push on memnode_worklist
   800 //               MergeMem: push on mergemem_worklist
   801 //  Phase 3:  Process MergeMem nodes from mergemem_worklist.  Walk each memory slice
   802 //            moving the first node encountered of each  instance type to the
   803 //            the input corresponding to its alias index.
   804 //            appropriate memory slice.
   805 //  Phase 4:  Update the inputs of non-instance memory Phis and the Memory input of memnodes.
   806 //
   807 // In the following example, the CheckCastPP nodes are the cast of allocation
   808 // results and the allocation of node 29 is unescaped and eligible to be an
   809 // instance type.
   810 //
   811 // We start with:
   812 //
   813 //     7 Parm #memory
   814 //    10  ConI  "12"
   815 //    19  CheckCastPP   "Foo"
   816 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   817 //    29  CheckCastPP   "Foo"
   818 //    30  AddP  _ 29 29 10  Foo+12  alias_index=4
   819 //
   820 //    40  StoreP  25   7  20   ... alias_index=4
   821 //    50  StoreP  35  40  30   ... alias_index=4
   822 //    60  StoreP  45  50  20   ... alias_index=4
   823 //    70  LoadP    _  60  30   ... alias_index=4
   824 //    80  Phi     75  50  60   Memory alias_index=4
   825 //    90  LoadP    _  80  30   ... alias_index=4
   826 //   100  LoadP    _  80  20   ... alias_index=4
   827 //
   828 //
   829 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
   830 // and creating a new alias index for node 30.  This gives:
   831 //
   832 //     7 Parm #memory
   833 //    10  ConI  "12"
   834 //    19  CheckCastPP   "Foo"
   835 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   836 //    29  CheckCastPP   "Foo"  iid=24
   837 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
   838 //
   839 //    40  StoreP  25   7  20   ... alias_index=4
   840 //    50  StoreP  35  40  30   ... alias_index=6
   841 //    60  StoreP  45  50  20   ... alias_index=4
   842 //    70  LoadP    _  60  30   ... alias_index=6
   843 //    80  Phi     75  50  60   Memory alias_index=4
   844 //    90  LoadP    _  80  30   ... alias_index=6
   845 //   100  LoadP    _  80  20   ... alias_index=4
   846 //
   847 // In phase 2, new memory inputs are computed for the loads and stores,
   848 // And a new version of the phi is created.  In phase 4, the inputs to
   849 // node 80 are updated and then the memory nodes are updated with the
   850 // values computed in phase 2.  This results in:
   851 //
   852 //     7 Parm #memory
   853 //    10  ConI  "12"
   854 //    19  CheckCastPP   "Foo"
   855 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   856 //    29  CheckCastPP   "Foo"  iid=24
   857 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
   858 //
   859 //    40  StoreP  25  7   20   ... alias_index=4
   860 //    50  StoreP  35  7   30   ... alias_index=6
   861 //    60  StoreP  45  40  20   ... alias_index=4
   862 //    70  LoadP    _  50  30   ... alias_index=6
   863 //    80  Phi     75  40  60   Memory alias_index=4
   864 //   120  Phi     75  50  50   Memory alias_index=6
   865 //    90  LoadP    _ 120  30   ... alias_index=6
   866 //   100  LoadP    _  80  20   ... alias_index=4
   867 //
   868 void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist) {
   869   GrowableArray<Node *>  memnode_worklist;
   870   GrowableArray<Node *>  mergemem_worklist;
   871   GrowableArray<PhiNode *>  orig_phis;
   872   PhaseGVN  *igvn = _compile->initial_gvn();
   873   uint new_index_start = (uint) _compile->num_alias_types();
   874   VectorSet visited(Thread::current()->resource_area());
   875   VectorSet ptset(Thread::current()->resource_area());
   878   //  Phase 1:  Process possible allocations from alloc_worklist.
   879   //  Create instance types for the CheckCastPP for allocations where possible.
   880   //
   881   // (Note: don't forget to change the order of the second AddP node on
   882   //  the alloc_worklist if the order of the worklist processing is changed,
   883   //  see the comment in find_second_addp().)
   884   //
   885   while (alloc_worklist.length() != 0) {
   886     Node *n = alloc_worklist.pop();
   887     uint ni = n->_idx;
   888     const TypeOopPtr* tinst = NULL;
   889     if (n->is_Call()) {
   890       CallNode *alloc = n->as_Call();
   891       // copy escape information to call node
   892       PointsToNode* ptn = ptnode_adr(alloc->_idx);
   893       PointsToNode::EscapeState es = escape_state(alloc, igvn);
   894       // We have an allocation or call which returns a Java object,
   895       // see if it is unescaped.
   896       if (es != PointsToNode::NoEscape || !ptn->_scalar_replaceable)
   897         continue;
   898       if (alloc->is_Allocate()) {
   899         // Set the scalar_replaceable flag before the next check.
   900         alloc->as_Allocate()->_is_scalar_replaceable = true;
   901       }
   902       // find CheckCastPP of call return value
   903       n = alloc->result_cast();
   904       if (n == NULL ||          // No uses accept Initialize or
   905           !n->is_CheckCastPP()) // not unique CheckCastPP.
   906         continue;
   907       // The inline code for Object.clone() casts the allocation result to
   908       // java.lang.Object and then to the actual type of the allocated
   909       // object. Detect this case and use the second cast.
   910       // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
   911       // the allocation result is cast to java.lang.Object and then
   912       // to the actual Array type.
   913       if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
   914           && (alloc->is_AllocateArray() ||
   915               igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
   916         Node *cast2 = NULL;
   917         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
   918           Node *use = n->fast_out(i);
   919           if (use->is_CheckCastPP()) {
   920             cast2 = use;
   921             break;
   922           }
   923         }
   924         if (cast2 != NULL) {
   925           n = cast2;
   926         } else {
   927           continue;
   928         }
   929       }
   930       set_escape_state(n->_idx, es);
   931       // in order for an object to be scalar-replaceable, it must be:
   932       //   - a direct allocation (not a call returning an object)
   933       //   - non-escaping
   934       //   - eligible to be a unique type
   935       //   - not determined to be ineligible by escape analysis
   936       set_map(alloc->_idx, n);
   937       set_map(n->_idx, alloc);
   938       const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
   939       if (t == NULL)
   940         continue;  // not a TypeInstPtr
   941       tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni);
   942       igvn->hash_delete(n);
   943       igvn->set_type(n,  tinst);
   944       n->raise_bottom_type(tinst);
   945       igvn->hash_insert(n);
   946       record_for_optimizer(n);
   947       if (alloc->is_Allocate() && ptn->_scalar_replaceable &&
   948           (t->isa_instptr() || t->isa_aryptr())) {
   950         // First, put on the worklist all Field edges from Connection Graph
   951         // which is more accurate then putting immediate users from Ideal Graph.
   952         for (uint e = 0; e < ptn->edge_count(); e++) {
   953           Node *use = ptnode_adr(ptn->edge_target(e))->_node;
   954           assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(),
   955                  "only AddP nodes are Field edges in CG");
   956           if (use->outcnt() > 0) { // Don't process dead nodes
   957             Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
   958             if (addp2 != NULL) {
   959               assert(alloc->is_AllocateArray(),"array allocation was expected");
   960               alloc_worklist.append_if_missing(addp2);
   961             }
   962             alloc_worklist.append_if_missing(use);
   963           }
   964         }
   966         // An allocation may have an Initialize which has raw stores. Scan
   967         // the users of the raw allocation result and push AddP users
   968         // on alloc_worklist.
   969         Node *raw_result = alloc->proj_out(TypeFunc::Parms);
   970         assert (raw_result != NULL, "must have an allocation result");
   971         for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
   972           Node *use = raw_result->fast_out(i);
   973           if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
   974             Node* addp2 = find_second_addp(use, raw_result);
   975             if (addp2 != NULL) {
   976               assert(alloc->is_AllocateArray(),"array allocation was expected");
   977               alloc_worklist.append_if_missing(addp2);
   978             }
   979             alloc_worklist.append_if_missing(use);
   980           } else if (use->is_Initialize()) {
   981             memnode_worklist.append_if_missing(use);
   982           }
   983         }
   984       }
   985     } else if (n->is_AddP()) {
   986       ptset.Clear();
   987       PointsTo(ptset, get_addp_base(n), igvn);
   988       assert(ptset.Size() == 1, "AddP address is unique");
   989       uint elem = ptset.getelem(); // Allocation node's index
   990       if (elem == _phantom_object)
   991         continue; // Assume the value was set outside this method.
   992       Node *base = get_map(elem);  // CheckCastPP node
   993       if (!split_AddP(n, base, igvn)) continue; // wrong type
   994       tinst = igvn->type(base)->isa_oopptr();
   995     } else if (n->is_Phi() ||
   996                n->is_CheckCastPP() ||
   997                n->is_EncodeP() ||
   998                n->is_DecodeN() ||
   999                (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
  1000       if (visited.test_set(n->_idx)) {
  1001         assert(n->is_Phi(), "loops only through Phi's");
  1002         continue;  // already processed
  1004       ptset.Clear();
  1005       PointsTo(ptset, n, igvn);
  1006       if (ptset.Size() == 1) {
  1007         uint elem = ptset.getelem(); // Allocation node's index
  1008         if (elem == _phantom_object)
  1009           continue; // Assume the value was set outside this method.
  1010         Node *val = get_map(elem);   // CheckCastPP node
  1011         TypeNode *tn = n->as_Type();
  1012         tinst = igvn->type(val)->isa_oopptr();
  1013         assert(tinst != NULL && tinst->is_known_instance() &&
  1014                (uint)tinst->instance_id() == elem , "instance type expected.");
  1016         const Type *tn_type = igvn->type(tn);
  1017         const TypeOopPtr *tn_t;
  1018         if (tn_type->isa_narrowoop()) {
  1019           tn_t = tn_type->make_ptr()->isa_oopptr();
  1020         } else {
  1021           tn_t = tn_type->isa_oopptr();
  1024         if (tn_t != NULL &&
  1025             tinst->cast_to_instance_id(TypeOopPtr::InstanceBot)->higher_equal(tn_t)) {
  1026           if (tn_type->isa_narrowoop()) {
  1027             tn_type = tinst->make_narrowoop();
  1028           } else {
  1029             tn_type = tinst;
  1031           igvn->hash_delete(tn);
  1032           igvn->set_type(tn, tn_type);
  1033           tn->set_type(tn_type);
  1034           igvn->hash_insert(tn);
  1035           record_for_optimizer(n);
  1036         } else {
  1037           continue; // wrong type
  1040     } else {
  1041       continue;
  1043     // push users on appropriate worklist
  1044     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1045       Node *use = n->fast_out(i);
  1046       if(use->is_Mem() && use->in(MemNode::Address) == n) {
  1047         memnode_worklist.append_if_missing(use);
  1048       } else if (use->is_Initialize()) {
  1049         memnode_worklist.append_if_missing(use);
  1050       } else if (use->is_MergeMem()) {
  1051         mergemem_worklist.append_if_missing(use);
  1052       } else if (use->is_SafePoint() && tinst != NULL) {
  1053         // Look for MergeMem nodes for calls which reference unique allocation
  1054         // (through CheckCastPP nodes) even for debug info.
  1055         Node* m = use->in(TypeFunc::Memory);
  1056         uint iid = tinst->instance_id();
  1057         while (m->is_Proj() && m->in(0)->is_SafePoint() &&
  1058                m->in(0) != use && !m->in(0)->_idx != iid) {
  1059           m = m->in(0)->in(TypeFunc::Memory);
  1061         if (m->is_MergeMem()) {
  1062           mergemem_worklist.append_if_missing(m);
  1064       } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
  1065         Node* addp2 = find_second_addp(use, n);
  1066         if (addp2 != NULL) {
  1067           alloc_worklist.append_if_missing(addp2);
  1069         alloc_worklist.append_if_missing(use);
  1070       } else if (use->is_Phi() ||
  1071                  use->is_CheckCastPP() ||
  1072                  use->is_EncodeP() ||
  1073                  use->is_DecodeN() ||
  1074                  (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
  1075         alloc_worklist.append_if_missing(use);
  1080   // New alias types were created in split_AddP().
  1081   uint new_index_end = (uint) _compile->num_alias_types();
  1083   //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
  1084   //            compute new values for Memory inputs  (the Memory inputs are not
  1085   //            actually updated until phase 4.)
  1086   if (memnode_worklist.length() == 0)
  1087     return;  // nothing to do
  1089   while (memnode_worklist.length() != 0) {
  1090     Node *n = memnode_worklist.pop();
  1091     if (visited.test_set(n->_idx))
  1092       continue;
  1093     if (n->is_Phi()) {
  1094       assert(n->as_Phi()->adr_type() != TypePtr::BOTTOM, "narrow memory slice required");
  1095       // we don't need to do anything, but the users must be pushed if we haven't processed
  1096       // this Phi before
  1097     } else if (n->is_Initialize()) {
  1098       // we don't need to do anything, but the users of the memory projection must be pushed
  1099       n = n->as_Initialize()->proj_out(TypeFunc::Memory);
  1100       if (n == NULL)
  1101         continue;
  1102     } else {
  1103       assert(n->is_Mem(), "memory node required.");
  1104       Node *addr = n->in(MemNode::Address);
  1105       assert(addr->is_AddP(), "AddP required");
  1106       const Type *addr_t = igvn->type(addr);
  1107       if (addr_t == Type::TOP)
  1108         continue;
  1109       assert (addr_t->isa_ptr() != NULL, "pointer type required.");
  1110       int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
  1111       assert ((uint)alias_idx < new_index_end, "wrong alias index");
  1112       Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn);
  1113       if (_compile->failing()) {
  1114         return;
  1116       if (mem != n->in(MemNode::Memory)) {
  1117         set_map(n->_idx, mem);
  1118         ptnode_adr(n->_idx)->_node = n;
  1120       if (n->is_Load()) {
  1121         continue;  // don't push users
  1122       } else if (n->is_LoadStore()) {
  1123         // get the memory projection
  1124         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1125           Node *use = n->fast_out(i);
  1126           if (use->Opcode() == Op_SCMemProj) {
  1127             n = use;
  1128             break;
  1131         assert(n->Opcode() == Op_SCMemProj, "memory projection required");
  1134     // push user on appropriate worklist
  1135     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1136       Node *use = n->fast_out(i);
  1137       if (use->is_Phi()) {
  1138         memnode_worklist.append_if_missing(use);
  1139       } else if(use->is_Mem() && use->in(MemNode::Memory) == n) {
  1140         memnode_worklist.append_if_missing(use);
  1141       } else if (use->is_Initialize()) {
  1142         memnode_worklist.append_if_missing(use);
  1143       } else if (use->is_MergeMem()) {
  1144         mergemem_worklist.append_if_missing(use);
  1149   //  Phase 3:  Process MergeMem nodes from mergemem_worklist.
  1150   //            Walk each memory moving the first node encountered of each
  1151   //            instance type to the the input corresponding to its alias index.
  1152   while (mergemem_worklist.length() != 0) {
  1153     Node *n = mergemem_worklist.pop();
  1154     assert(n->is_MergeMem(), "MergeMem node required.");
  1155     if (visited.test_set(n->_idx))
  1156       continue;
  1157     MergeMemNode *nmm = n->as_MergeMem();
  1158     // Note: we don't want to use MergeMemStream here because we only want to
  1159     //  scan inputs which exist at the start, not ones we add during processing.
  1160     uint nslices = nmm->req();
  1161     igvn->hash_delete(nmm);
  1162     for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
  1163       Node* mem = nmm->in(i);
  1164       Node* cur = NULL;
  1165       if (mem == NULL || mem->is_top())
  1166         continue;
  1167       while (mem->is_Mem()) {
  1168         const Type *at = igvn->type(mem->in(MemNode::Address));
  1169         if (at != Type::TOP) {
  1170           assert (at->isa_ptr() != NULL, "pointer type required.");
  1171           uint idx = (uint)_compile->get_alias_index(at->is_ptr());
  1172           if (idx == i) {
  1173             if (cur == NULL)
  1174               cur = mem;
  1175           } else {
  1176             if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
  1177               nmm->set_memory_at(idx, mem);
  1181         mem = mem->in(MemNode::Memory);
  1183       nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
  1184       // Find any instance of the current type if we haven't encountered
  1185       // a value of the instance along the chain.
  1186       for (uint ni = new_index_start; ni < new_index_end; ni++) {
  1187         if((uint)_compile->get_general_index(ni) == i) {
  1188           Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
  1189           if (nmm->is_empty_memory(m)) {
  1190             Node* result = find_inst_mem(mem, ni, orig_phis, igvn);
  1191             if (_compile->failing()) {
  1192               return;
  1194             nmm->set_memory_at(ni, result);
  1199     // Find the rest of instances values
  1200     for (uint ni = new_index_start; ni < new_index_end; ni++) {
  1201       const TypeOopPtr *tinst = igvn->C->get_adr_type(ni)->isa_oopptr();
  1202       Node* result = step_through_mergemem(nmm, ni, tinst);
  1203       if (result == nmm->base_memory()) {
  1204         // Didn't find instance memory, search through general slice recursively.
  1205         result = nmm->memory_at(igvn->C->get_general_index(ni));
  1206         result = find_inst_mem(result, ni, orig_phis, igvn);
  1207         if (_compile->failing()) {
  1208           return;
  1210         nmm->set_memory_at(ni, result);
  1213     igvn->hash_insert(nmm);
  1214     record_for_optimizer(nmm);
  1216     // Propagate new memory slices to following MergeMem nodes.
  1217     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1218       Node *use = n->fast_out(i);
  1219       if (use->is_Call()) {
  1220         CallNode* in = use->as_Call();
  1221         if (in->proj_out(TypeFunc::Memory) != NULL) {
  1222           Node* m = in->proj_out(TypeFunc::Memory);
  1223           for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
  1224             Node* mm = m->fast_out(j);
  1225             if (mm->is_MergeMem()) {
  1226               mergemem_worklist.append_if_missing(mm);
  1230         if (use->is_Allocate()) {
  1231           use = use->as_Allocate()->initialization();
  1232           if (use == NULL) {
  1233             continue;
  1237       if (use->is_Initialize()) {
  1238         InitializeNode* in = use->as_Initialize();
  1239         if (in->proj_out(TypeFunc::Memory) != NULL) {
  1240           Node* m = in->proj_out(TypeFunc::Memory);
  1241           for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
  1242             Node* mm = m->fast_out(j);
  1243             if (mm->is_MergeMem()) {
  1244               mergemem_worklist.append_if_missing(mm);
  1252   //  Phase 4:  Update the inputs of non-instance memory Phis and
  1253   //            the Memory input of memnodes
  1254   // First update the inputs of any non-instance Phi's from
  1255   // which we split out an instance Phi.  Note we don't have
  1256   // to recursively process Phi's encounted on the input memory
  1257   // chains as is done in split_memory_phi() since they  will
  1258   // also be processed here.
  1259   for (int j = 0; j < orig_phis.length(); j++) {
  1260     PhiNode *phi = orig_phis.at(j);
  1261     int alias_idx = _compile->get_alias_index(phi->adr_type());
  1262     igvn->hash_delete(phi);
  1263     for (uint i = 1; i < phi->req(); i++) {
  1264       Node *mem = phi->in(i);
  1265       Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn);
  1266       if (_compile->failing()) {
  1267         return;
  1269       if (mem != new_mem) {
  1270         phi->set_req(i, new_mem);
  1273     igvn->hash_insert(phi);
  1274     record_for_optimizer(phi);
  1277   // Update the memory inputs of MemNodes with the value we computed
  1278   // in Phase 2.
  1279   for (uint i = 0; i < nodes_size(); i++) {
  1280     Node *nmem = get_map(i);
  1281     if (nmem != NULL) {
  1282       Node *n = ptnode_adr(i)->_node;
  1283       if (n != NULL && n->is_Mem()) {
  1284         igvn->hash_delete(n);
  1285         n->set_req(MemNode::Memory, nmem);
  1286         igvn->hash_insert(n);
  1287         record_for_optimizer(n);
  1293 bool ConnectionGraph::has_candidates(Compile *C) {
  1294   // EA brings benefits only when the code has allocations and/or locks which
  1295   // are represented by ideal Macro nodes.
  1296   int cnt = C->macro_count();
  1297   for( int i=0; i < cnt; i++ ) {
  1298     Node *n = C->macro_node(i);
  1299     if ( n->is_Allocate() )
  1300       return true;
  1301     if( n->is_Lock() ) {
  1302       Node* obj = n->as_Lock()->obj_node()->uncast();
  1303       if( !(obj->is_Parm() || obj->is_Con()) )
  1304         return true;
  1307   return false;
  1310 bool ConnectionGraph::compute_escape() {
  1311   Compile* C = _compile;
  1313   // 1. Populate Connection Graph (CG) with Ideal nodes.
  1315   Unique_Node_List worklist_init;
  1316   worklist_init.map(C->unique(), NULL);  // preallocate space
  1318   // Initialize worklist
  1319   if (C->root() != NULL) {
  1320     worklist_init.push(C->root());
  1323   GrowableArray<int> cg_worklist;
  1324   PhaseGVN* igvn = C->initial_gvn();
  1325   bool has_allocations = false;
  1327   // Push all useful nodes onto CG list and set their type.
  1328   for( uint next = 0; next < worklist_init.size(); ++next ) {
  1329     Node* n = worklist_init.at(next);
  1330     record_for_escape_analysis(n, igvn);
  1331     // Only allocations and java static calls results are checked
  1332     // for an escape status. See process_call_result() below.
  1333     if (n->is_Allocate() || n->is_CallStaticJava() &&
  1334         ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) {
  1335       has_allocations = true;
  1337     if(n->is_AddP())
  1338       cg_worklist.append(n->_idx);
  1339     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1340       Node* m = n->fast_out(i);   // Get user
  1341       worklist_init.push(m);
  1345   if (!has_allocations) {
  1346     _collecting = false;
  1347     return false; // Nothing to do.
  1350   // 2. First pass to create simple CG edges (doesn't require to walk CG).
  1351   uint delayed_size = _delayed_worklist.size();
  1352   for( uint next = 0; next < delayed_size; ++next ) {
  1353     Node* n = _delayed_worklist.at(next);
  1354     build_connection_graph(n, igvn);
  1357   // 3. Pass to create fields edges (Allocate -F-> AddP).
  1358   uint cg_length = cg_worklist.length();
  1359   for( uint next = 0; next < cg_length; ++next ) {
  1360     int ni = cg_worklist.at(next);
  1361     build_connection_graph(ptnode_adr(ni)->_node, igvn);
  1364   cg_worklist.clear();
  1365   cg_worklist.append(_phantom_object);
  1367   // 4. Build Connection Graph which need
  1368   //    to walk the connection graph.
  1369   for (uint ni = 0; ni < nodes_size(); ni++) {
  1370     PointsToNode* ptn = ptnode_adr(ni);
  1371     Node *n = ptn->_node;
  1372     if (n != NULL) { // Call, AddP, LoadP, StoreP
  1373       build_connection_graph(n, igvn);
  1374       if (ptn->node_type() != PointsToNode::UnknownType)
  1375         cg_worklist.append(n->_idx); // Collect CG nodes
  1379   VectorSet ptset(Thread::current()->resource_area());
  1380   GrowableArray<uint>  deferred_edges;
  1381   VectorSet visited(Thread::current()->resource_area());
  1383   // 5. Remove deferred edges from the graph and collect
  1384   //    information needed for type splitting.
  1385   cg_length = cg_worklist.length();
  1386   for( uint next = 0; next < cg_length; ++next ) {
  1387     int ni = cg_worklist.at(next);
  1388     PointsToNode* ptn = ptnode_adr(ni);
  1389     PointsToNode::NodeType nt = ptn->node_type();
  1390     if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) {
  1391       remove_deferred(ni, &deferred_edges, &visited);
  1392       Node *n = ptn->_node;
  1393       if (n->is_AddP()) {
  1394         // Search for objects which are not scalar replaceable.
  1395         // Mark their escape state as ArgEscape to propagate the state
  1396         // to referenced objects.
  1397         // Note: currently there are no difference in compiler optimizations
  1398         // for ArgEscape objects and NoEscape objects which are not
  1399         // scalar replaceable.
  1401         int offset = ptn->offset();
  1402         Node *base = get_addp_base(n);
  1403         ptset.Clear();
  1404         PointsTo(ptset, base, igvn);
  1405         int ptset_size = ptset.Size();
  1407         // Check if a field's initializing value is recorded and add
  1408         // a corresponding NULL field's value if it is not recorded.
  1409         // Connection Graph does not record a default initialization by NULL
  1410         // captured by Initialize node.
  1411         //
  1412         // Note: it will disable scalar replacement in some cases:
  1413         //
  1414         //    Point p[] = new Point[1];
  1415         //    p[0] = new Point(); // Will be not scalar replaced
  1416         //
  1417         // but it will save us from incorrect optimizations in next cases:
  1418         //
  1419         //    Point p[] = new Point[1];
  1420         //    if ( x ) p[0] = new Point(); // Will be not scalar replaced
  1421         //
  1422         // Without a control flow analysis we can't distinguish above cases.
  1423         //
  1424         if (offset != Type::OffsetBot && ptset_size == 1) {
  1425           uint elem = ptset.getelem(); // Allocation node's index
  1426           // It does not matter if it is not Allocation node since
  1427           // only non-escaping allocations are scalar replaced.
  1428           if (ptnode_adr(elem)->_node->is_Allocate() &&
  1429               ptnode_adr(elem)->escape_state() == PointsToNode::NoEscape) {
  1430             AllocateNode* alloc = ptnode_adr(elem)->_node->as_Allocate();
  1431             InitializeNode* ini = alloc->initialization();
  1432             Node* value = NULL;
  1433             if (ini != NULL) {
  1434               BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT;
  1435               Node* store = ini->find_captured_store(offset, type2aelembytes(ft), igvn);
  1436               if (store != NULL && store->is_Store())
  1437                 value = store->in(MemNode::ValueIn);
  1439             if (value == NULL || value != ptnode_adr(value->_idx)->_node) {
  1440               // A field's initializing value was not recorded. Add NULL.
  1441               uint null_idx = UseCompressedOops ? _noop_null : _oop_null;
  1442               add_pointsto_edge(ni, null_idx);
  1447         // An object is not scalar replaceable if the field which may point
  1448         // to it has unknown offset (unknown element of an array of objects).
  1449         //
  1450         if (offset == Type::OffsetBot) {
  1451           uint e_cnt = ptn->edge_count();
  1452           for (uint ei = 0; ei < e_cnt; ei++) {
  1453             uint npi = ptn->edge_target(ei);
  1454             set_escape_state(npi, PointsToNode::ArgEscape);
  1455             ptnode_adr(npi)->_scalar_replaceable = false;
  1459         // Currently an object is not scalar replaceable if a LoadStore node
  1460         // access its field since the field value is unknown after it.
  1461         //
  1462         bool has_LoadStore = false;
  1463         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1464           Node *use = n->fast_out(i);
  1465           if (use->is_LoadStore()) {
  1466             has_LoadStore = true;
  1467             break;
  1470         // An object is not scalar replaceable if the address points
  1471         // to unknown field (unknown element for arrays, offset is OffsetBot).
  1472         //
  1473         // Or the address may point to more then one object. This may produce
  1474         // the false positive result (set scalar_replaceable to false)
  1475         // since the flow-insensitive escape analysis can't separate
  1476         // the case when stores overwrite the field's value from the case
  1477         // when stores happened on different control branches.
  1478         //
  1479         if (ptset_size > 1 || ptset_size != 0 &&
  1480             (has_LoadStore || offset == Type::OffsetBot)) {
  1481           for( VectorSetI j(&ptset); j.test(); ++j ) {
  1482             set_escape_state(j.elem, PointsToNode::ArgEscape);
  1483             ptnode_adr(j.elem)->_scalar_replaceable = false;
  1490   // 6. Propagate escape states.
  1491   GrowableArray<int>  worklist;
  1492   bool has_non_escaping_obj = false;
  1494   // push all GlobalEscape nodes on the worklist
  1495   for( uint next = 0; next < cg_length; ++next ) {
  1496     int nk = cg_worklist.at(next);
  1497     if (ptnode_adr(nk)->escape_state() == PointsToNode::GlobalEscape)
  1498       worklist.push(nk);
  1500   // mark all nodes reachable from GlobalEscape nodes
  1501   while(worklist.length() > 0) {
  1502     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1503     uint e_cnt = ptn->edge_count();
  1504     for (uint ei = 0; ei < e_cnt; ei++) {
  1505       uint npi = ptn->edge_target(ei);
  1506       PointsToNode *np = ptnode_adr(npi);
  1507       if (np->escape_state() < PointsToNode::GlobalEscape) {
  1508         np->set_escape_state(PointsToNode::GlobalEscape);
  1509         worklist.push(npi);
  1514   // push all ArgEscape nodes on the worklist
  1515   for( uint next = 0; next < cg_length; ++next ) {
  1516     int nk = cg_worklist.at(next);
  1517     if (ptnode_adr(nk)->escape_state() == PointsToNode::ArgEscape)
  1518       worklist.push(nk);
  1520   // mark all nodes reachable from ArgEscape nodes
  1521   while(worklist.length() > 0) {
  1522     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1523     if (ptn->node_type() == PointsToNode::JavaObject)
  1524       has_non_escaping_obj = true; // Non GlobalEscape
  1525     uint e_cnt = ptn->edge_count();
  1526     for (uint ei = 0; ei < e_cnt; ei++) {
  1527       uint npi = ptn->edge_target(ei);
  1528       PointsToNode *np = ptnode_adr(npi);
  1529       if (np->escape_state() < PointsToNode::ArgEscape) {
  1530         np->set_escape_state(PointsToNode::ArgEscape);
  1531         worklist.push(npi);
  1536   GrowableArray<Node*> alloc_worklist;
  1538   // push all NoEscape 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::NoEscape)
  1542       worklist.push(nk);
  1544   // mark all nodes reachable from NoEscape nodes
  1545   while(worklist.length() > 0) {
  1546     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1547     if (ptn->node_type() == PointsToNode::JavaObject)
  1548       has_non_escaping_obj = true; // Non GlobalEscape
  1549     Node* n = ptn->_node;
  1550     if (n->is_Allocate() && ptn->_scalar_replaceable ) {
  1551       // Push scalar replaceable alocations on alloc_worklist
  1552       // for processing in split_unique_types().
  1553       alloc_worklist.append(n);
  1555     uint e_cnt = ptn->edge_count();
  1556     for (uint ei = 0; ei < e_cnt; ei++) {
  1557       uint npi = ptn->edge_target(ei);
  1558       PointsToNode *np = ptnode_adr(npi);
  1559       if (np->escape_state() < PointsToNode::NoEscape) {
  1560         np->set_escape_state(PointsToNode::NoEscape);
  1561         worklist.push(npi);
  1566   _collecting = false;
  1567   assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build");
  1569   bool has_scalar_replaceable_candidates = alloc_worklist.length() > 0;
  1570   if ( has_scalar_replaceable_candidates &&
  1571        C->AliasLevel() >= 3 && EliminateAllocations ) {
  1573     // Now use the escape information to create unique types for
  1574     // scalar replaceable objects.
  1575     split_unique_types(alloc_worklist);
  1577     if (C->failing())  return false;
  1579     // Clean up after split unique types.
  1580     ResourceMark rm;
  1581     PhaseRemoveUseless pru(C->initial_gvn(), C->for_igvn());
  1583     C->print_method("After Escape Analysis", 2);
  1585 #ifdef ASSERT
  1586   } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
  1587     tty->print("=== No allocations eliminated for ");
  1588     C->method()->print_short_name();
  1589     if(!EliminateAllocations) {
  1590       tty->print(" since EliminateAllocations is off ===");
  1591     } else if(!has_scalar_replaceable_candidates) {
  1592       tty->print(" since there are no scalar replaceable candidates ===");
  1593     } else if(C->AliasLevel() < 3) {
  1594       tty->print(" since AliasLevel < 3 ===");
  1596     tty->cr();
  1597 #endif
  1599   return has_non_escaping_obj;
  1602 void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) {
  1604     switch (call->Opcode()) {
  1605 #ifdef ASSERT
  1606     case Op_Allocate:
  1607     case Op_AllocateArray:
  1608     case Op_Lock:
  1609     case Op_Unlock:
  1610       assert(false, "should be done already");
  1611       break;
  1612 #endif
  1613     case Op_CallLeafNoFP:
  1615       // Stub calls, objects do not escape but they are not scale replaceable.
  1616       // Adjust escape state for outgoing arguments.
  1617       const TypeTuple * d = call->tf()->domain();
  1618       VectorSet ptset(Thread::current()->resource_area());
  1619       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1620         const Type* at = d->field_at(i);
  1621         Node *arg = call->in(i)->uncast();
  1622         const Type *aat = phase->type(arg);
  1623         if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr()) {
  1624           assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
  1625                  aat->isa_ptr() != NULL, "expecting an Ptr");
  1626           set_escape_state(arg->_idx, PointsToNode::ArgEscape);
  1627           if (arg->is_AddP()) {
  1628             //
  1629             // The inline_native_clone() case when the arraycopy stub is called
  1630             // after the allocation before Initialize and CheckCastPP nodes.
  1631             //
  1632             // Set AddP's base (Allocate) as not scalar replaceable since
  1633             // pointer to the base (with offset) is passed as argument.
  1634             //
  1635             arg = get_addp_base(arg);
  1637           ptset.Clear();
  1638           PointsTo(ptset, arg, phase);
  1639           for( VectorSetI j(&ptset); j.test(); ++j ) {
  1640             uint pt = j.elem;
  1641             set_escape_state(pt, PointsToNode::ArgEscape);
  1645       break;
  1648     case Op_CallStaticJava:
  1649     // For a static call, we know exactly what method is being called.
  1650     // Use bytecode estimator to record the call's escape affects
  1652       ciMethod *meth = call->as_CallJava()->method();
  1653       BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
  1654       // fall-through if not a Java method or no analyzer information
  1655       if (call_analyzer != NULL) {
  1656         const TypeTuple * d = call->tf()->domain();
  1657         VectorSet ptset(Thread::current()->resource_area());
  1658         bool copy_dependencies = false;
  1659         for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1660           const Type* at = d->field_at(i);
  1661           int k = i - TypeFunc::Parms;
  1663           if (at->isa_oopptr() != NULL) {
  1664             Node *arg = call->in(i)->uncast();
  1666             bool global_escapes = false;
  1667             bool fields_escapes = false;
  1668             if (!call_analyzer->is_arg_stack(k)) {
  1669               // The argument global escapes, mark everything it could point to
  1670               set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
  1671               global_escapes = true;
  1672             } else {
  1673               if (!call_analyzer->is_arg_local(k)) {
  1674                 // The argument itself doesn't escape, but any fields might
  1675                 fields_escapes = true;
  1677               set_escape_state(arg->_idx, PointsToNode::ArgEscape);
  1678               copy_dependencies = true;
  1681             ptset.Clear();
  1682             PointsTo(ptset, arg, phase);
  1683             for( VectorSetI j(&ptset); j.test(); ++j ) {
  1684               uint pt = j.elem;
  1685               if (global_escapes) {
  1686                 //The argument global escapes, mark everything it could point to
  1687                 set_escape_state(pt, PointsToNode::GlobalEscape);
  1688               } else {
  1689                 if (fields_escapes) {
  1690                   // The argument itself doesn't escape, but any fields might
  1691                   add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
  1693                 set_escape_state(pt, PointsToNode::ArgEscape);
  1698         if (copy_dependencies)
  1699           call_analyzer->copy_dependencies(_compile->dependencies());
  1700         break;
  1704     default:
  1705     // Fall-through here if not a Java method or no analyzer information
  1706     // or some other type of call, assume the worst case: all arguments
  1707     // globally escape.
  1709       // adjust escape state for  outgoing arguments
  1710       const TypeTuple * d = call->tf()->domain();
  1711       VectorSet ptset(Thread::current()->resource_area());
  1712       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1713         const Type* at = d->field_at(i);
  1714         if (at->isa_oopptr() != NULL) {
  1715           Node *arg = call->in(i)->uncast();
  1716           set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
  1717           ptset.Clear();
  1718           PointsTo(ptset, arg, phase);
  1719           for( VectorSetI j(&ptset); j.test(); ++j ) {
  1720             uint pt = j.elem;
  1721             set_escape_state(pt, PointsToNode::GlobalEscape);
  1728 void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) {
  1729   CallNode   *call = resproj->in(0)->as_Call();
  1730   uint    call_idx = call->_idx;
  1731   uint resproj_idx = resproj->_idx;
  1733   switch (call->Opcode()) {
  1734     case Op_Allocate:
  1736       Node *k = call->in(AllocateNode::KlassNode);
  1737       const TypeKlassPtr *kt;
  1738       if (k->Opcode() == Op_LoadKlass) {
  1739         kt = k->as_Load()->type()->isa_klassptr();
  1740       } else {
  1741         // Also works for DecodeN(LoadNKlass).
  1742         kt = k->as_Type()->type()->isa_klassptr();
  1744       assert(kt != NULL, "TypeKlassPtr  required.");
  1745       ciKlass* cik = kt->klass();
  1746       ciInstanceKlass* ciik = cik->as_instance_klass();
  1748       PointsToNode::EscapeState es;
  1749       uint edge_to;
  1750       if (cik->is_subclass_of(_compile->env()->Thread_klass()) || ciik->has_finalizer()) {
  1751         es = PointsToNode::GlobalEscape;
  1752         edge_to = _phantom_object; // Could not be worse
  1753       } else {
  1754         es = PointsToNode::NoEscape;
  1755         edge_to = call_idx;
  1757       set_escape_state(call_idx, es);
  1758       add_pointsto_edge(resproj_idx, edge_to);
  1759       _processed.set(resproj_idx);
  1760       break;
  1763     case Op_AllocateArray:
  1765       int length = call->in(AllocateNode::ALength)->find_int_con(-1);
  1766       if (length < 0 || length > EliminateAllocationArraySizeLimit) {
  1767         // Not scalar replaceable if the length is not constant or too big.
  1768         ptnode_adr(call_idx)->_scalar_replaceable = false;
  1770       set_escape_state(call_idx, PointsToNode::NoEscape);
  1771       add_pointsto_edge(resproj_idx, call_idx);
  1772       _processed.set(resproj_idx);
  1773       break;
  1776     case Op_CallStaticJava:
  1777     // For a static call, we know exactly what method is being called.
  1778     // Use bytecode estimator to record whether the call's return value escapes
  1780       bool done = true;
  1781       const TypeTuple *r = call->tf()->range();
  1782       const Type* ret_type = NULL;
  1784       if (r->cnt() > TypeFunc::Parms)
  1785         ret_type = r->field_at(TypeFunc::Parms);
  1787       // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
  1788       //        _multianewarray functions return a TypeRawPtr.
  1789       if (ret_type == NULL || ret_type->isa_ptr() == NULL) {
  1790         _processed.set(resproj_idx);
  1791         break;  // doesn't return a pointer type
  1793       ciMethod *meth = call->as_CallJava()->method();
  1794       const TypeTuple * d = call->tf()->domain();
  1795       if (meth == NULL) {
  1796         // not a Java method, assume global escape
  1797         set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1798         add_pointsto_edge(resproj_idx, _phantom_object);
  1799       } else {
  1800         BCEscapeAnalyzer *call_analyzer = meth->get_bcea();
  1801         bool copy_dependencies = false;
  1803         if (call_analyzer->is_return_allocated()) {
  1804           // Returns a newly allocated unescaped object, simply
  1805           // update dependency information.
  1806           // Mark it as NoEscape so that objects referenced by
  1807           // it's fields will be marked as NoEscape at least.
  1808           set_escape_state(call_idx, PointsToNode::NoEscape);
  1809           add_pointsto_edge(resproj_idx, call_idx);
  1810           copy_dependencies = true;
  1811         } else if (call_analyzer->is_return_local()) {
  1812           // determine whether any arguments are returned
  1813           set_escape_state(call_idx, PointsToNode::NoEscape);
  1814           bool ret_arg = false;
  1815           for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1816             const Type* at = d->field_at(i);
  1818             if (at->isa_oopptr() != NULL) {
  1819               Node *arg = call->in(i)->uncast();
  1821               if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
  1822                 ret_arg = true;
  1823                 PointsToNode *arg_esp = ptnode_adr(arg->_idx);
  1824                 if (arg_esp->node_type() == PointsToNode::UnknownType)
  1825                   done = false;
  1826                 else if (arg_esp->node_type() == PointsToNode::JavaObject)
  1827                   add_pointsto_edge(resproj_idx, arg->_idx);
  1828                 else
  1829                   add_deferred_edge(resproj_idx, arg->_idx);
  1830                 arg_esp->_hidden_alias = true;
  1834           if (done && !ret_arg) {
  1835             // Returns unknown object.
  1836             set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1837             add_pointsto_edge(resproj_idx, _phantom_object);
  1839           copy_dependencies = true;
  1840         } else {
  1841           set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1842           add_pointsto_edge(resproj_idx, _phantom_object);
  1843           for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1844             const Type* at = d->field_at(i);
  1845             if (at->isa_oopptr() != NULL) {
  1846               Node *arg = call->in(i)->uncast();
  1847               PointsToNode *arg_esp = ptnode_adr(arg->_idx);
  1848               arg_esp->_hidden_alias = true;
  1852         if (copy_dependencies)
  1853           call_analyzer->copy_dependencies(_compile->dependencies());
  1855       if (done)
  1856         _processed.set(resproj_idx);
  1857       break;
  1860     default:
  1861     // Some other type of call, assume the worst case that the
  1862     // returned value, if any, globally escapes.
  1864       const TypeTuple *r = call->tf()->range();
  1865       if (r->cnt() > TypeFunc::Parms) {
  1866         const Type* ret_type = r->field_at(TypeFunc::Parms);
  1868         // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
  1869         //        _multianewarray functions return a TypeRawPtr.
  1870         if (ret_type->isa_ptr() != NULL) {
  1871           set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1872           add_pointsto_edge(resproj_idx, _phantom_object);
  1875       _processed.set(resproj_idx);
  1880 // Populate Connection Graph with Ideal nodes and create simple
  1881 // connection graph edges (do not need to check the node_type of inputs
  1882 // or to call PointsTo() to walk the connection graph).
  1883 void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) {
  1884   if (_processed.test(n->_idx))
  1885     return; // No need to redefine node's state.
  1887   if (n->is_Call()) {
  1888     // Arguments to allocation and locking don't escape.
  1889     if (n->is_Allocate()) {
  1890       add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true);
  1891       record_for_optimizer(n);
  1892     } else if (n->is_Lock() || n->is_Unlock()) {
  1893       // Put Lock and Unlock nodes on IGVN worklist to process them during
  1894       // the first IGVN optimization when escape information is still available.
  1895       record_for_optimizer(n);
  1896       _processed.set(n->_idx);
  1897     } else {
  1898       // Have to process call's arguments first.
  1899       PointsToNode::NodeType nt = PointsToNode::UnknownType;
  1901       // Check if a call returns an object.
  1902       const TypeTuple *r = n->as_Call()->tf()->range();
  1903       if (n->is_CallStaticJava() && r->cnt() > TypeFunc::Parms &&
  1904           n->as_Call()->proj_out(TypeFunc::Parms) != NULL) {
  1905         // Note:  use isa_ptr() instead of isa_oopptr() here because
  1906         //        the _multianewarray functions return a TypeRawPtr.
  1907         if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
  1908           nt = PointsToNode::JavaObject;
  1911       add_node(n, nt, PointsToNode::UnknownEscape, false);
  1913     return;
  1916   // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
  1917   // ThreadLocal has RawPrt type.
  1918   switch (n->Opcode()) {
  1919     case Op_AddP:
  1921       add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false);
  1922       break;
  1924     case Op_CastX2P:
  1925     { // "Unsafe" memory access.
  1926       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  1927       break;
  1929     case Op_CastPP:
  1930     case Op_CheckCastPP:
  1931     case Op_EncodeP:
  1932     case Op_DecodeN:
  1934       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  1935       int ti = n->in(1)->_idx;
  1936       PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  1937       if (nt == PointsToNode::UnknownType) {
  1938         _delayed_worklist.push(n); // Process it later.
  1939         break;
  1940       } else if (nt == PointsToNode::JavaObject) {
  1941         add_pointsto_edge(n->_idx, ti);
  1942       } else {
  1943         add_deferred_edge(n->_idx, ti);
  1945       _processed.set(n->_idx);
  1946       break;
  1948     case Op_ConP:
  1950       // assume all pointer constants globally escape except for null
  1951       PointsToNode::EscapeState es;
  1952       if (phase->type(n) == TypePtr::NULL_PTR)
  1953         es = PointsToNode::NoEscape;
  1954       else
  1955         es = PointsToNode::GlobalEscape;
  1957       add_node(n, PointsToNode::JavaObject, es, true);
  1958       break;
  1960     case Op_ConN:
  1962       // assume all narrow oop constants globally escape except for null
  1963       PointsToNode::EscapeState es;
  1964       if (phase->type(n) == TypeNarrowOop::NULL_PTR)
  1965         es = PointsToNode::NoEscape;
  1966       else
  1967         es = PointsToNode::GlobalEscape;
  1969       add_node(n, PointsToNode::JavaObject, es, true);
  1970       break;
  1972     case Op_CreateEx:
  1974       // assume that all exception objects globally escape
  1975       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  1976       break;
  1978     case Op_LoadKlass:
  1979     case Op_LoadNKlass:
  1981       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  1982       break;
  1984     case Op_LoadP:
  1985     case Op_LoadN:
  1987       const Type *t = phase->type(n);
  1988       if (t->make_ptr() == NULL) {
  1989         _processed.set(n->_idx);
  1990         return;
  1992       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  1993       break;
  1995     case Op_Parm:
  1997       _processed.set(n->_idx); // No need to redefine it state.
  1998       uint con = n->as_Proj()->_con;
  1999       if (con < TypeFunc::Parms)
  2000         return;
  2001       const Type *t = n->in(0)->as_Start()->_domain->field_at(con);
  2002       if (t->isa_ptr() == NULL)
  2003         return;
  2004       // We have to assume all input parameters globally escape
  2005       // (Note: passing 'false' since _processed is already set).
  2006       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false);
  2007       break;
  2009     case Op_Phi:
  2011       const Type *t = n->as_Phi()->type();
  2012       if (t->make_ptr() == NULL) {
  2013         // nothing to do if not an oop or narrow oop
  2014         _processed.set(n->_idx);
  2015         return;
  2017       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2018       uint i;
  2019       for (i = 1; i < n->req() ; i++) {
  2020         Node* in = n->in(i);
  2021         if (in == NULL)
  2022           continue;  // ignore NULL
  2023         in = in->uncast();
  2024         if (in->is_top() || in == n)
  2025           continue;  // ignore top or inputs which go back this node
  2026         int ti = in->_idx;
  2027         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2028         if (nt == PointsToNode::UnknownType) {
  2029           break;
  2030         } else if (nt == PointsToNode::JavaObject) {
  2031           add_pointsto_edge(n->_idx, ti);
  2032         } else {
  2033           add_deferred_edge(n->_idx, ti);
  2036       if (i >= n->req())
  2037         _processed.set(n->_idx);
  2038       else
  2039         _delayed_worklist.push(n);
  2040       break;
  2042     case Op_Proj:
  2044       // we are only interested in the result projection from a call
  2045       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
  2046         add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2047         process_call_result(n->as_Proj(), phase);
  2048         if (!_processed.test(n->_idx)) {
  2049           // The call's result may need to be processed later if the call
  2050           // returns it's argument and the argument is not processed yet.
  2051           _delayed_worklist.push(n);
  2053       } else {
  2054         _processed.set(n->_idx);
  2056       break;
  2058     case Op_Return:
  2060       if( n->req() > TypeFunc::Parms &&
  2061           phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
  2062         // Treat Return value as LocalVar with GlobalEscape escape state.
  2063         add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false);
  2064         int ti = n->in(TypeFunc::Parms)->_idx;
  2065         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2066         if (nt == PointsToNode::UnknownType) {
  2067           _delayed_worklist.push(n); // Process it later.
  2068           break;
  2069         } else if (nt == PointsToNode::JavaObject) {
  2070           add_pointsto_edge(n->_idx, ti);
  2071         } else {
  2072           add_deferred_edge(n->_idx, ti);
  2075       _processed.set(n->_idx);
  2076       break;
  2078     case Op_StoreP:
  2079     case Op_StoreN:
  2081       const Type *adr_type = phase->type(n->in(MemNode::Address));
  2082       adr_type = adr_type->make_ptr();
  2083       if (adr_type->isa_oopptr()) {
  2084         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2085       } else {
  2086         Node* adr = n->in(MemNode::Address);
  2087         if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL &&
  2088             adr->in(AddPNode::Address)->is_Proj() &&
  2089             adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
  2090           add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2091           // We are computing a raw address for a store captured
  2092           // by an Initialize compute an appropriate address type.
  2093           int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
  2094           assert(offs != Type::OffsetBot, "offset must be a constant");
  2095         } else {
  2096           _processed.set(n->_idx);
  2097           return;
  2100       break;
  2102     case Op_StorePConditional:
  2103     case Op_CompareAndSwapP:
  2104     case Op_CompareAndSwapN:
  2106       const Type *adr_type = phase->type(n->in(MemNode::Address));
  2107       adr_type = adr_type->make_ptr();
  2108       if (adr_type->isa_oopptr()) {
  2109         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2110       } else {
  2111         _processed.set(n->_idx);
  2112         return;
  2114       break;
  2116     case Op_ThreadLocal:
  2118       add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true);
  2119       break;
  2121     default:
  2123       // nothing to do
  2125   return;
  2128 void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) {
  2129   uint n_idx = n->_idx;
  2131   // Don't set processed bit for AddP, LoadP, StoreP since
  2132   // they may need more then one pass to process.
  2133   if (_processed.test(n_idx))
  2134     return; // No need to redefine node's state.
  2136   if (n->is_Call()) {
  2137     CallNode *call = n->as_Call();
  2138     process_call_arguments(call, phase);
  2139     _processed.set(n_idx);
  2140     return;
  2143   switch (n->Opcode()) {
  2144     case Op_AddP:
  2146       Node *base = get_addp_base(n);
  2147       // Create a field edge to this node from everything base could point to.
  2148       VectorSet ptset(Thread::current()->resource_area());
  2149       PointsTo(ptset, base, phase);
  2150       for( VectorSetI i(&ptset); i.test(); ++i ) {
  2151         uint pt = i.elem;
  2152         add_field_edge(pt, n_idx, address_offset(n, phase));
  2154       break;
  2156     case Op_CastX2P:
  2158       assert(false, "Op_CastX2P");
  2159       break;
  2161     case Op_CastPP:
  2162     case Op_CheckCastPP:
  2163     case Op_EncodeP:
  2164     case Op_DecodeN:
  2166       int ti = n->in(1)->_idx;
  2167       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
  2168         add_pointsto_edge(n_idx, ti);
  2169       } else {
  2170         add_deferred_edge(n_idx, ti);
  2172       _processed.set(n_idx);
  2173       break;
  2175     case Op_ConP:
  2177       assert(false, "Op_ConP");
  2178       break;
  2180     case Op_ConN:
  2182       assert(false, "Op_ConN");
  2183       break;
  2185     case Op_CreateEx:
  2187       assert(false, "Op_CreateEx");
  2188       break;
  2190     case Op_LoadKlass:
  2191     case Op_LoadNKlass:
  2193       assert(false, "Op_LoadKlass");
  2194       break;
  2196     case Op_LoadP:
  2197     case Op_LoadN:
  2199       const Type *t = phase->type(n);
  2200 #ifdef ASSERT
  2201       if (t->make_ptr() == NULL)
  2202         assert(false, "Op_LoadP");
  2203 #endif
  2205       Node* adr = n->in(MemNode::Address)->uncast();
  2206       const Type *adr_type = phase->type(adr);
  2207       Node* adr_base;
  2208       if (adr->is_AddP()) {
  2209         adr_base = get_addp_base(adr);
  2210       } else {
  2211         adr_base = adr;
  2214       // For everything "adr_base" could point to, create a deferred edge from
  2215       // this node to each field with the same offset.
  2216       VectorSet ptset(Thread::current()->resource_area());
  2217       PointsTo(ptset, adr_base, phase);
  2218       int offset = address_offset(adr, phase);
  2219       for( VectorSetI i(&ptset); i.test(); ++i ) {
  2220         uint pt = i.elem;
  2221         add_deferred_edge_to_fields(n_idx, pt, offset);
  2223       break;
  2225     case Op_Parm:
  2227       assert(false, "Op_Parm");
  2228       break;
  2230     case Op_Phi:
  2232 #ifdef ASSERT
  2233       const Type *t = n->as_Phi()->type();
  2234       if (t->make_ptr() == NULL)
  2235         assert(false, "Op_Phi");
  2236 #endif
  2237       for (uint i = 1; i < n->req() ; i++) {
  2238         Node* in = n->in(i);
  2239         if (in == NULL)
  2240           continue;  // ignore NULL
  2241         in = in->uncast();
  2242         if (in->is_top() || in == n)
  2243           continue;  // ignore top or inputs which go back this node
  2244         int ti = in->_idx;
  2245         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2246         assert(nt != PointsToNode::UnknownType, "all nodes should be known");
  2247         if (nt == PointsToNode::JavaObject) {
  2248           add_pointsto_edge(n_idx, ti);
  2249         } else {
  2250           add_deferred_edge(n_idx, ti);
  2253       _processed.set(n_idx);
  2254       break;
  2256     case Op_Proj:
  2258       // we are only interested in the result projection from a call
  2259       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
  2260         process_call_result(n->as_Proj(), phase);
  2261         assert(_processed.test(n_idx), "all call results should be processed");
  2262       } else {
  2263         assert(false, "Op_Proj");
  2265       break;
  2267     case Op_Return:
  2269 #ifdef ASSERT
  2270       if( n->req() <= TypeFunc::Parms ||
  2271           !phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
  2272         assert(false, "Op_Return");
  2274 #endif
  2275       int ti = n->in(TypeFunc::Parms)->_idx;
  2276       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
  2277         add_pointsto_edge(n_idx, ti);
  2278       } else {
  2279         add_deferred_edge(n_idx, ti);
  2281       _processed.set(n_idx);
  2282       break;
  2284     case Op_StoreP:
  2285     case Op_StoreN:
  2286     case Op_StorePConditional:
  2287     case Op_CompareAndSwapP:
  2288     case Op_CompareAndSwapN:
  2290       Node *adr = n->in(MemNode::Address);
  2291       const Type *adr_type = phase->type(adr)->make_ptr();
  2292 #ifdef ASSERT
  2293       if (!adr_type->isa_oopptr())
  2294         assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP");
  2295 #endif
  2297       assert(adr->is_AddP(), "expecting an AddP");
  2298       Node *adr_base = get_addp_base(adr);
  2299       Node *val = n->in(MemNode::ValueIn)->uncast();
  2300       // For everything "adr_base" could point to, create a deferred edge
  2301       // to "val" from each field with the same offset.
  2302       VectorSet ptset(Thread::current()->resource_area());
  2303       PointsTo(ptset, adr_base, phase);
  2304       for( VectorSetI i(&ptset); i.test(); ++i ) {
  2305         uint pt = i.elem;
  2306         add_edge_from_fields(pt, val->_idx, address_offset(adr, phase));
  2308       break;
  2310     case Op_ThreadLocal:
  2312       assert(false, "Op_ThreadLocal");
  2313       break;
  2315     default:
  2317       // nothing to do
  2321 #ifndef PRODUCT
  2322 void ConnectionGraph::dump() {
  2323   PhaseGVN  *igvn = _compile->initial_gvn();
  2324   bool first = true;
  2326   uint size = nodes_size();
  2327   for (uint ni = 0; ni < size; ni++) {
  2328     PointsToNode *ptn = ptnode_adr(ni);
  2329     PointsToNode::NodeType ptn_type = ptn->node_type();
  2331     if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL)
  2332       continue;
  2333     PointsToNode::EscapeState es = escape_state(ptn->_node, igvn);
  2334     if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) {
  2335       if (first) {
  2336         tty->cr();
  2337         tty->print("======== Connection graph for ");
  2338         _compile->method()->print_short_name();
  2339         tty->cr();
  2340         first = false;
  2342       tty->print("%6d ", ni);
  2343       ptn->dump();
  2344       // Print all locals which reference this allocation
  2345       for (uint li = ni; li < size; li++) {
  2346         PointsToNode *ptn_loc = ptnode_adr(li);
  2347         PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type();
  2348         if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL &&
  2349              ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) {
  2350           ptnode_adr(li)->dump(false);
  2353       if (Verbose) {
  2354         // Print all fields which reference this allocation
  2355         for (uint i = 0; i < ptn->edge_count(); i++) {
  2356           uint ei = ptn->edge_target(i);
  2357           ptnode_adr(ei)->dump(false);
  2360       tty->cr();
  2364 #endif

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