src/share/vm/opto/escape.cpp

Fri, 07 Nov 2008 09:29:38 -0800

author
kvn
date
Fri, 07 Nov 2008 09:29:38 -0800
changeset 855
a1980da045cc
parent 742
892493c3d862
child 895
424f9bfe6b96
permissions
-rw-r--r--

6462850: generate biased locking code in C2 ideal graph
Summary: Inline biased locking code in C2 ideal graph during macro nodes expansion
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     return es;
   205   // PointsTo() calls n->uncast() which can return a new ideal node.
   206   if (n->uncast()->_idx >= nodes_size())
   207     return PointsToNode::UnknownEscape;
   209   // compute max escape state of anything this node could point to
   210   VectorSet ptset(Thread::current()->resource_area());
   211   PointsTo(ptset, n, phase);
   212   for(VectorSetI i(&ptset); i.test() && es != PointsToNode::GlobalEscape; ++i) {
   213     uint pt = i.elem;
   214     PointsToNode::EscapeState pes = ptnode_adr(pt)->escape_state();
   215     if (pes > es)
   216       es = pes;
   217   }
   218   // cache the computed escape state
   219   assert(es != PointsToNode::UnknownEscape, "should have computed an escape state");
   220   ptnode_adr(idx)->set_escape_state(es);
   221   return es;
   222 }
   224 void ConnectionGraph::PointsTo(VectorSet &ptset, Node * n, PhaseTransform *phase) {
   225   VectorSet visited(Thread::current()->resource_area());
   226   GrowableArray<uint>  worklist;
   228 #ifdef ASSERT
   229   Node *orig_n = n;
   230 #endif
   232   n = n->uncast();
   233   PointsToNode* npt = ptnode_adr(n->_idx);
   235   // If we have a JavaObject, return just that object
   236   if (npt->node_type() == PointsToNode::JavaObject) {
   237     ptset.set(n->_idx);
   238     return;
   239   }
   240 #ifdef ASSERT
   241   if (npt->_node == NULL) {
   242     if (orig_n != n)
   243       orig_n->dump();
   244     n->dump();
   245     assert(npt->_node != NULL, "unregistered node");
   246   }
   247 #endif
   248   worklist.push(n->_idx);
   249   while(worklist.length() > 0) {
   250     int ni = worklist.pop();
   251     if (visited.test_set(ni))
   252       continue;
   254     PointsToNode* pn = ptnode_adr(ni);
   255     // ensure that all inputs of a Phi have been processed
   256     assert(!_collecting || !pn->_node->is_Phi() || _processed.test(ni),"");
   258     int edges_processed = 0;
   259     uint e_cnt = pn->edge_count();
   260     for (uint e = 0; e < e_cnt; e++) {
   261       uint etgt = pn->edge_target(e);
   262       PointsToNode::EdgeType et = pn->edge_type(e);
   263       if (et == PointsToNode::PointsToEdge) {
   264         ptset.set(etgt);
   265         edges_processed++;
   266       } else if (et == PointsToNode::DeferredEdge) {
   267         worklist.push(etgt);
   268         edges_processed++;
   269       } else {
   270         assert(false,"neither PointsToEdge or DeferredEdge");
   271       }
   272     }
   273     if (edges_processed == 0) {
   274       // no deferred or pointsto edges found.  Assume the value was set
   275       // outside this method.  Add the phantom object to the pointsto set.
   276       ptset.set(_phantom_object);
   277     }
   278   }
   279 }
   281 void ConnectionGraph::remove_deferred(uint ni, GrowableArray<uint>* deferred_edges, VectorSet* visited) {
   282   // This method is most expensive during ConnectionGraph construction.
   283   // Reuse vectorSet and an additional growable array for deferred edges.
   284   deferred_edges->clear();
   285   visited->Clear();
   287   visited->set(ni);
   288   PointsToNode *ptn = ptnode_adr(ni);
   290   // Mark current edges as visited and move deferred edges to separate array.
   291   for (uint i = 0; i < ptn->edge_count(); ) {
   292     uint t = ptn->edge_target(i);
   293 #ifdef ASSERT
   294     assert(!visited->test_set(t), "expecting no duplications");
   295 #else
   296     visited->set(t);
   297 #endif
   298     if (ptn->edge_type(i) == PointsToNode::DeferredEdge) {
   299       ptn->remove_edge(t, PointsToNode::DeferredEdge);
   300       deferred_edges->append(t);
   301     } else {
   302       i++;
   303     }
   304   }
   305   for (int next = 0; next < deferred_edges->length(); ++next) {
   306     uint t = deferred_edges->at(next);
   307     PointsToNode *ptt = ptnode_adr(t);
   308     uint e_cnt = ptt->edge_count();
   309     for (uint e = 0; e < e_cnt; e++) {
   310       uint etgt = ptt->edge_target(e);
   311       if (visited->test_set(etgt))
   312         continue;
   314       PointsToNode::EdgeType et = ptt->edge_type(e);
   315       if (et == PointsToNode::PointsToEdge) {
   316         add_pointsto_edge(ni, etgt);
   317         if(etgt == _phantom_object) {
   318           // Special case - field set outside (globally escaping).
   319           ptn->set_escape_state(PointsToNode::GlobalEscape);
   320         }
   321       } else if (et == PointsToNode::DeferredEdge) {
   322         deferred_edges->append(etgt);
   323       } else {
   324         assert(false,"invalid connection graph");
   325       }
   326     }
   327   }
   328 }
   331 //  Add an edge to node given by "to_i" from any field of adr_i whose offset
   332 //  matches "offset"  A deferred edge is added if to_i is a LocalVar, and
   333 //  a pointsto edge is added if it is a JavaObject
   335 void ConnectionGraph::add_edge_from_fields(uint adr_i, uint to_i, int offs) {
   336   PointsToNode* an = ptnode_adr(adr_i);
   337   PointsToNode* to = ptnode_adr(to_i);
   338   bool deferred = (to->node_type() == PointsToNode::LocalVar);
   340   for (uint fe = 0; fe < an->edge_count(); fe++) {
   341     assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
   342     int fi = an->edge_target(fe);
   343     PointsToNode* pf = ptnode_adr(fi);
   344     int po = pf->offset();
   345     if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
   346       if (deferred)
   347         add_deferred_edge(fi, to_i);
   348       else
   349         add_pointsto_edge(fi, to_i);
   350     }
   351   }
   352 }
   354 // Add a deferred  edge from node given by "from_i" to any field of adr_i
   355 // whose offset matches "offset".
   356 void ConnectionGraph::add_deferred_edge_to_fields(uint from_i, uint adr_i, int offs) {
   357   PointsToNode* an = ptnode_adr(adr_i);
   358   for (uint fe = 0; fe < an->edge_count(); fe++) {
   359     assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
   360     int fi = an->edge_target(fe);
   361     PointsToNode* pf = ptnode_adr(fi);
   362     int po = pf->offset();
   363     if (pf->edge_count() == 0) {
   364       // we have not seen any stores to this field, assume it was set outside this method
   365       add_pointsto_edge(fi, _phantom_object);
   366     }
   367     if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
   368       add_deferred_edge(from_i, fi);
   369     }
   370   }
   371 }
   373 // Helper functions
   375 static Node* get_addp_base(Node *addp) {
   376   assert(addp->is_AddP(), "must be AddP");
   377   //
   378   // AddP cases for Base and Address inputs:
   379   // case #1. Direct object's field reference:
   380   //     Allocate
   381   //       |
   382   //     Proj #5 ( oop result )
   383   //       |
   384   //     CheckCastPP (cast to instance type)
   385   //      | |
   386   //     AddP  ( base == address )
   387   //
   388   // case #2. Indirect object's field reference:
   389   //      Phi
   390   //       |
   391   //     CastPP (cast to instance type)
   392   //      | |
   393   //     AddP  ( base == address )
   394   //
   395   // case #3. Raw object's field reference for Initialize node:
   396   //      Allocate
   397   //        |
   398   //      Proj #5 ( oop result )
   399   //  top   |
   400   //     \  |
   401   //     AddP  ( base == top )
   402   //
   403   // case #4. Array's element reference:
   404   //   {CheckCastPP | CastPP}
   405   //     |  | |
   406   //     |  AddP ( array's element offset )
   407   //     |  |
   408   //     AddP ( array's offset )
   409   //
   410   // case #5. Raw object's field reference for arraycopy stub call:
   411   //          The inline_native_clone() case when the arraycopy stub is called
   412   //          after the allocation before Initialize and CheckCastPP nodes.
   413   //      Allocate
   414   //        |
   415   //      Proj #5 ( oop result )
   416   //       | |
   417   //       AddP  ( base == address )
   418   //
   419   // case #6. Constant Pool, ThreadLocal, CastX2P or
   420   //          Raw object's field reference:
   421   //      {ConP, ThreadLocal, CastX2P, raw Load}
   422   //  top   |
   423   //     \  |
   424   //     AddP  ( base == top )
   425   //
   426   // case #7. Klass's field reference.
   427   //      LoadKlass
   428   //       | |
   429   //       AddP  ( base == address )
   430   //
   431   // case #8. narrow Klass's field reference.
   432   //      LoadNKlass
   433   //       |
   434   //      DecodeN
   435   //       | |
   436   //       AddP  ( base == address )
   437   //
   438   Node *base = addp->in(AddPNode::Base)->uncast();
   439   if (base->is_top()) { // The AddP case #3 and #6.
   440     base = addp->in(AddPNode::Address)->uncast();
   441     assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal ||
   442            base->Opcode() == Op_CastX2P || base->is_DecodeN() ||
   443            (base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) ||
   444            (base->is_Proj() && base->in(0)->is_Allocate()), "sanity");
   445   }
   446   return base;
   447 }
   449 static Node* find_second_addp(Node* addp, Node* n) {
   450   assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
   452   Node* addp2 = addp->raw_out(0);
   453   if (addp->outcnt() == 1 && addp2->is_AddP() &&
   454       addp2->in(AddPNode::Base) == n &&
   455       addp2->in(AddPNode::Address) == addp) {
   457     assert(addp->in(AddPNode::Base) == n, "expecting the same base");
   458     //
   459     // Find array's offset to push it on worklist first and
   460     // as result process an array's element offset first (pushed second)
   461     // to avoid CastPP for the array's offset.
   462     // Otherwise the inserted CastPP (LocalVar) will point to what
   463     // the AddP (Field) points to. Which would be wrong since
   464     // the algorithm expects the CastPP has the same point as
   465     // as AddP's base CheckCastPP (LocalVar).
   466     //
   467     //    ArrayAllocation
   468     //     |
   469     //    CheckCastPP
   470     //     |
   471     //    memProj (from ArrayAllocation CheckCastPP)
   472     //     |  ||
   473     //     |  ||   Int (element index)
   474     //     |  ||    |   ConI (log(element size))
   475     //     |  ||    |   /
   476     //     |  ||   LShift
   477     //     |  ||  /
   478     //     |  AddP (array's element offset)
   479     //     |  |
   480     //     |  | ConI (array's offset: #12(32-bits) or #24(64-bits))
   481     //     | / /
   482     //     AddP (array's offset)
   483     //      |
   484     //     Load/Store (memory operation on array's element)
   485     //
   486     return addp2;
   487   }
   488   return NULL;
   489 }
   491 //
   492 // Adjust the type and inputs of an AddP which computes the
   493 // address of a field of an instance
   494 //
   495 bool ConnectionGraph::split_AddP(Node *addp, Node *base,  PhaseGVN  *igvn) {
   496   const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
   497   assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
   498   const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
   499   if (t == NULL) {
   500     // We are computing a raw address for a store captured by an Initialize
   501     // compute an appropriate address type (cases #3 and #5).
   502     assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
   503     assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
   504     intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
   505     assert(offs != Type::OffsetBot, "offset must be a constant");
   506     t = base_t->add_offset(offs)->is_oopptr();
   507   }
   508   int inst_id =  base_t->instance_id();
   509   assert(!t->is_known_instance() || t->instance_id() == inst_id,
   510                              "old type must be non-instance or match new type");
   512   // The type 't' could be subclass of 'base_t'.
   513   // As result t->offset() could be large then base_t's size and it will
   514   // cause the failure in add_offset() with narrow oops since TypeOopPtr()
   515   // constructor verifies correctness of the offset.
   516   //
   517   // It could happend on subclass's branch (from the type profiling
   518   // inlining) which was not eliminated during parsing since the exactness
   519   // of the allocation type was not propagated to the subclass type check.
   520   //
   521   // Do nothing for such AddP node and don't process its users since
   522   // this code branch will go away.
   523   //
   524   if (!t->is_known_instance() &&
   525       !t->klass()->equals(base_t->klass()) &&
   526       t->klass()->is_subtype_of(base_t->klass())) {
   527      return false; // bail out
   528   }
   530   const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
   531   // Do NOT remove the next call: ensure an new alias index is allocated
   532   // for the instance type
   533   int alias_idx = _compile->get_alias_index(tinst);
   534   igvn->set_type(addp, tinst);
   535   // record the allocation in the node map
   536   set_map(addp->_idx, get_map(base->_idx));
   538   // Set addp's Base and Address to 'base'.
   539   Node *abase = addp->in(AddPNode::Base);
   540   Node *adr   = addp->in(AddPNode::Address);
   541   if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
   542       adr->in(0)->_idx == (uint)inst_id) {
   543     // Skip AddP cases #3 and #5.
   544   } else {
   545     assert(!abase->is_top(), "sanity"); // AddP case #3
   546     if (abase != base) {
   547       igvn->hash_delete(addp);
   548       addp->set_req(AddPNode::Base, base);
   549       if (abase == adr) {
   550         addp->set_req(AddPNode::Address, base);
   551       } else {
   552         // AddP case #4 (adr is array's element offset AddP node)
   553 #ifdef ASSERT
   554         const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
   555         assert(adr->is_AddP() && atype != NULL &&
   556                atype->instance_id() == inst_id, "array's element offset should be processed first");
   557 #endif
   558       }
   559       igvn->hash_insert(addp);
   560     }
   561   }
   562   // Put on IGVN worklist since at least addp's type was changed above.
   563   record_for_optimizer(addp);
   564   return true;
   565 }
   567 //
   568 // Create a new version of orig_phi if necessary. Returns either the newly
   569 // created phi or an existing phi.  Sets create_new to indicate wheter  a new
   570 // phi was created.  Cache the last newly created phi in the node map.
   571 //
   572 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn, bool &new_created) {
   573   Compile *C = _compile;
   574   new_created = false;
   575   int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
   576   // nothing to do if orig_phi is bottom memory or matches alias_idx
   577   if (phi_alias_idx == alias_idx) {
   578     return orig_phi;
   579   }
   580   // have we already created a Phi for this alias index?
   581   PhiNode *result = get_map_phi(orig_phi->_idx);
   582   if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
   583     return result;
   584   }
   585   if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) {
   586     if (C->do_escape_analysis() == true && !C->failing()) {
   587       // Retry compilation without escape analysis.
   588       // If this is the first failure, the sentinel string will "stick"
   589       // to the Compile object, and the C2Compiler will see it and retry.
   590       C->record_failure(C2Compiler::retry_no_escape_analysis());
   591     }
   592     return NULL;
   593   }
   594   orig_phi_worklist.append_if_missing(orig_phi);
   595   const TypePtr *atype = C->get_adr_type(alias_idx);
   596   result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
   597   set_map_phi(orig_phi->_idx, result);
   598   igvn->set_type(result, result->bottom_type());
   599   record_for_optimizer(result);
   600   new_created = true;
   601   return result;
   602 }
   604 //
   605 // Return a new version  of Memory Phi "orig_phi" with the inputs having the
   606 // specified alias index.
   607 //
   608 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn) {
   610   assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
   611   Compile *C = _compile;
   612   bool new_phi_created;
   613   PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created);
   614   if (!new_phi_created) {
   615     return result;
   616   }
   618   GrowableArray<PhiNode *>  phi_list;
   619   GrowableArray<uint>  cur_input;
   621   PhiNode *phi = orig_phi;
   622   uint idx = 1;
   623   bool finished = false;
   624   while(!finished) {
   625     while (idx < phi->req()) {
   626       Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn);
   627       if (mem != NULL && mem->is_Phi()) {
   628         PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created);
   629         if (new_phi_created) {
   630           // found an phi for which we created a new split, push current one on worklist and begin
   631           // processing new one
   632           phi_list.push(phi);
   633           cur_input.push(idx);
   634           phi = mem->as_Phi();
   635           result = newphi;
   636           idx = 1;
   637           continue;
   638         } else {
   639           mem = newphi;
   640         }
   641       }
   642       if (C->failing()) {
   643         return NULL;
   644       }
   645       result->set_req(idx++, mem);
   646     }
   647 #ifdef ASSERT
   648     // verify that the new Phi has an input for each input of the original
   649     assert( phi->req() == result->req(), "must have same number of inputs.");
   650     assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
   651 #endif
   652     // Check if all new phi's inputs have specified alias index.
   653     // Otherwise use old phi.
   654     for (uint i = 1; i < phi->req(); i++) {
   655       Node* in = result->in(i);
   656       assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
   657     }
   658     // we have finished processing a Phi, see if there are any more to do
   659     finished = (phi_list.length() == 0 );
   660     if (!finished) {
   661       phi = phi_list.pop();
   662       idx = cur_input.pop();
   663       PhiNode *prev_result = get_map_phi(phi->_idx);
   664       prev_result->set_req(idx++, result);
   665       result = prev_result;
   666     }
   667   }
   668   return result;
   669 }
   672 //
   673 // The next methods are derived from methods in MemNode.
   674 //
   675 static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *tinst) {
   676   Node *mem = mmem;
   677   // TypeInstPtr::NOTNULL+any is an OOP with unknown offset - generally
   678   // means an array I have not precisely typed yet.  Do not do any
   679   // alias stuff with it any time soon.
   680   if( tinst->base() != Type::AnyPtr &&
   681       !(tinst->klass()->is_java_lang_Object() &&
   682         tinst->offset() == Type::OffsetBot) ) {
   683     mem = mmem->memory_at(alias_idx);
   684     // Update input if it is progress over what we have now
   685   }
   686   return mem;
   687 }
   689 //
   690 // Search memory chain of "mem" to find a MemNode whose address
   691 // is the specified alias index.
   692 //
   693 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *>  &orig_phis, PhaseGVN *phase) {
   694   if (orig_mem == NULL)
   695     return orig_mem;
   696   Compile* C = phase->C;
   697   const TypeOopPtr *tinst = C->get_adr_type(alias_idx)->isa_oopptr();
   698   bool is_instance = (tinst != NULL) && tinst->is_known_instance();
   699   Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
   700   Node *prev = NULL;
   701   Node *result = orig_mem;
   702   while (prev != result) {
   703     prev = result;
   704     if (result == start_mem)
   705       break;  // hit one of our sentinals
   706     if (result->is_Mem()) {
   707       const Type *at = phase->type(result->in(MemNode::Address));
   708       if (at != Type::TOP) {
   709         assert (at->isa_ptr() != NULL, "pointer type required.");
   710         int idx = C->get_alias_index(at->is_ptr());
   711         if (idx == alias_idx)
   712           break;
   713       }
   714       result = result->in(MemNode::Memory);
   715     }
   716     if (!is_instance)
   717       continue;  // don't search further for non-instance types
   718     // skip over a call which does not affect this memory slice
   719     if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
   720       Node *proj_in = result->in(0);
   721       if (proj_in->is_Allocate() && proj_in->_idx == (uint)tinst->instance_id()) {
   722         break;  // hit one of our sentinals
   723       } else if (proj_in->is_Call()) {
   724         CallNode *call = proj_in->as_Call();
   725         if (!call->may_modify(tinst, phase)) {
   726           result = call->in(TypeFunc::Memory);
   727         }
   728       } else if (proj_in->is_Initialize()) {
   729         AllocateNode* alloc = proj_in->as_Initialize()->allocation();
   730         // Stop if this is the initialization for the object instance which
   731         // which contains this memory slice, otherwise skip over it.
   732         if (alloc == NULL || alloc->_idx != (uint)tinst->instance_id()) {
   733           result = proj_in->in(TypeFunc::Memory);
   734         }
   735       } else if (proj_in->is_MemBar()) {
   736         result = proj_in->in(TypeFunc::Memory);
   737       }
   738     } else if (result->is_MergeMem()) {
   739       MergeMemNode *mmem = result->as_MergeMem();
   740       result = step_through_mergemem(mmem, alias_idx, tinst);
   741       if (result == mmem->base_memory()) {
   742         // Didn't find instance memory, search through general slice recursively.
   743         result = mmem->memory_at(C->get_general_index(alias_idx));
   744         result = find_inst_mem(result, alias_idx, orig_phis, phase);
   745         if (C->failing()) {
   746           return NULL;
   747         }
   748         mmem->set_memory_at(alias_idx, result);
   749       }
   750     } else if (result->is_Phi() &&
   751                C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
   752       Node *un = result->as_Phi()->unique_input(phase);
   753       if (un != NULL) {
   754         result = un;
   755       } else {
   756         break;
   757       }
   758     }
   759   }
   760   if (result->is_Phi()) {
   761     PhiNode *mphi = result->as_Phi();
   762     assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
   763     const TypePtr *t = mphi->adr_type();
   764     if (C->get_alias_index(t) != alias_idx) {
   765       // Create a new Phi with the specified alias index type.
   766       result = split_memory_phi(mphi, alias_idx, orig_phis, phase);
   767     } else if (!is_instance) {
   768       // Push all non-instance Phis on the orig_phis worklist to update inputs
   769       // during Phase 4 if needed.
   770       orig_phis.append_if_missing(mphi);
   771     }
   772   }
   773   // the result is either MemNode, PhiNode, InitializeNode.
   774   return result;
   775 }
   778 //
   779 //  Convert the types of unescaped object to instance types where possible,
   780 //  propagate the new type information through the graph, and update memory
   781 //  edges and MergeMem inputs to reflect the new type.
   782 //
   783 //  We start with allocations (and calls which may be allocations)  on alloc_worklist.
   784 //  The processing is done in 4 phases:
   785 //
   786 //  Phase 1:  Process possible allocations from alloc_worklist.  Create instance
   787 //            types for the CheckCastPP for allocations where possible.
   788 //            Propagate the the new types through users as follows:
   789 //               casts and Phi:  push users on alloc_worklist
   790 //               AddP:  cast Base and Address inputs to the instance type
   791 //                      push any AddP users on alloc_worklist and push any memnode
   792 //                      users onto memnode_worklist.
   793 //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
   794 //            search the Memory chain for a store with the appropriate type
   795 //            address type.  If a Phi is found, create a new version with
   796 //            the approriate memory slices from each of the Phi inputs.
   797 //            For stores, process the users as follows:
   798 //               MemNode:  push on memnode_worklist
   799 //               MergeMem: push on mergemem_worklist
   800 //  Phase 3:  Process MergeMem nodes from mergemem_worklist.  Walk each memory slice
   801 //            moving the first node encountered of each  instance type to the
   802 //            the input corresponding to its alias index.
   803 //            appropriate memory slice.
   804 //  Phase 4:  Update the inputs of non-instance memory Phis and the Memory input of memnodes.
   805 //
   806 // In the following example, the CheckCastPP nodes are the cast of allocation
   807 // results and the allocation of node 29 is unescaped and eligible to be an
   808 // instance type.
   809 //
   810 // We start with:
   811 //
   812 //     7 Parm #memory
   813 //    10  ConI  "12"
   814 //    19  CheckCastPP   "Foo"
   815 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   816 //    29  CheckCastPP   "Foo"
   817 //    30  AddP  _ 29 29 10  Foo+12  alias_index=4
   818 //
   819 //    40  StoreP  25   7  20   ... alias_index=4
   820 //    50  StoreP  35  40  30   ... alias_index=4
   821 //    60  StoreP  45  50  20   ... alias_index=4
   822 //    70  LoadP    _  60  30   ... alias_index=4
   823 //    80  Phi     75  50  60   Memory alias_index=4
   824 //    90  LoadP    _  80  30   ... alias_index=4
   825 //   100  LoadP    _  80  20   ... alias_index=4
   826 //
   827 //
   828 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
   829 // and creating a new alias index for node 30.  This gives:
   830 //
   831 //     7 Parm #memory
   832 //    10  ConI  "12"
   833 //    19  CheckCastPP   "Foo"
   834 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   835 //    29  CheckCastPP   "Foo"  iid=24
   836 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
   837 //
   838 //    40  StoreP  25   7  20   ... alias_index=4
   839 //    50  StoreP  35  40  30   ... alias_index=6
   840 //    60  StoreP  45  50  20   ... alias_index=4
   841 //    70  LoadP    _  60  30   ... alias_index=6
   842 //    80  Phi     75  50  60   Memory alias_index=4
   843 //    90  LoadP    _  80  30   ... alias_index=6
   844 //   100  LoadP    _  80  20   ... alias_index=4
   845 //
   846 // In phase 2, new memory inputs are computed for the loads and stores,
   847 // And a new version of the phi is created.  In phase 4, the inputs to
   848 // node 80 are updated and then the memory nodes are updated with the
   849 // values computed in phase 2.  This results in:
   850 //
   851 //     7 Parm #memory
   852 //    10  ConI  "12"
   853 //    19  CheckCastPP   "Foo"
   854 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   855 //    29  CheckCastPP   "Foo"  iid=24
   856 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
   857 //
   858 //    40  StoreP  25  7   20   ... alias_index=4
   859 //    50  StoreP  35  7   30   ... alias_index=6
   860 //    60  StoreP  45  40  20   ... alias_index=4
   861 //    70  LoadP    _  50  30   ... alias_index=6
   862 //    80  Phi     75  40  60   Memory alias_index=4
   863 //   120  Phi     75  50  50   Memory alias_index=6
   864 //    90  LoadP    _ 120  30   ... alias_index=6
   865 //   100  LoadP    _  80  20   ... alias_index=4
   866 //
   867 void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist) {
   868   GrowableArray<Node *>  memnode_worklist;
   869   GrowableArray<Node *>  mergemem_worklist;
   870   GrowableArray<PhiNode *>  orig_phis;
   871   PhaseGVN  *igvn = _compile->initial_gvn();
   872   uint new_index_start = (uint) _compile->num_alias_types();
   873   VectorSet visited(Thread::current()->resource_area());
   874   VectorSet ptset(Thread::current()->resource_area());
   877   //  Phase 1:  Process possible allocations from alloc_worklist.
   878   //  Create instance types for the CheckCastPP for allocations where possible.
   879   //
   880   // (Note: don't forget to change the order of the second AddP node on
   881   //  the alloc_worklist if the order of the worklist processing is changed,
   882   //  see the comment in find_second_addp().)
   883   //
   884   while (alloc_worklist.length() != 0) {
   885     Node *n = alloc_worklist.pop();
   886     uint ni = n->_idx;
   887     const TypeOopPtr* tinst = NULL;
   888     if (n->is_Call()) {
   889       CallNode *alloc = n->as_Call();
   890       // copy escape information to call node
   891       PointsToNode* ptn = ptnode_adr(alloc->_idx);
   892       PointsToNode::EscapeState es = escape_state(alloc, igvn);
   893       // We have an allocation or call which returns a Java object,
   894       // see if it is unescaped.
   895       if (es != PointsToNode::NoEscape || !ptn->_scalar_replaceable)
   896         continue;
   897       if (alloc->is_Allocate()) {
   898         // Set the scalar_replaceable flag before the next check.
   899         alloc->as_Allocate()->_is_scalar_replaceable = true;
   900       }
   901       // find CheckCastPP of call return value
   902       n = alloc->result_cast();
   903       if (n == NULL ||          // No uses accept Initialize or
   904           !n->is_CheckCastPP()) // not unique CheckCastPP.
   905         continue;
   906       // The inline code for Object.clone() casts the allocation result to
   907       // java.lang.Object and then to the actual type of the allocated
   908       // object. Detect this case and use the second cast.
   909       // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
   910       // the allocation result is cast to java.lang.Object and then
   911       // to the actual Array type.
   912       if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
   913           && (alloc->is_AllocateArray() ||
   914               igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
   915         Node *cast2 = NULL;
   916         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
   917           Node *use = n->fast_out(i);
   918           if (use->is_CheckCastPP()) {
   919             cast2 = use;
   920             break;
   921           }
   922         }
   923         if (cast2 != NULL) {
   924           n = cast2;
   925         } else {
   926           continue;
   927         }
   928       }
   929       set_escape_state(n->_idx, es);
   930       // in order for an object to be scalar-replaceable, it must be:
   931       //   - a direct allocation (not a call returning an object)
   932       //   - non-escaping
   933       //   - eligible to be a unique type
   934       //   - not determined to be ineligible by escape analysis
   935       set_map(alloc->_idx, n);
   936       set_map(n->_idx, alloc);
   937       const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
   938       if (t == NULL)
   939         continue;  // not a TypeInstPtr
   940       tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni);
   941       igvn->hash_delete(n);
   942       igvn->set_type(n,  tinst);
   943       n->raise_bottom_type(tinst);
   944       igvn->hash_insert(n);
   945       record_for_optimizer(n);
   946       if (alloc->is_Allocate() && ptn->_scalar_replaceable &&
   947           (t->isa_instptr() || t->isa_aryptr())) {
   949         // First, put on the worklist all Field edges from Connection Graph
   950         // which is more accurate then putting immediate users from Ideal Graph.
   951         for (uint e = 0; e < ptn->edge_count(); e++) {
   952           Node *use = ptnode_adr(ptn->edge_target(e))->_node;
   953           assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(),
   954                  "only AddP nodes are Field edges in CG");
   955           if (use->outcnt() > 0) { // Don't process dead nodes
   956             Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
   957             if (addp2 != NULL) {
   958               assert(alloc->is_AllocateArray(),"array allocation was expected");
   959               alloc_worklist.append_if_missing(addp2);
   960             }
   961             alloc_worklist.append_if_missing(use);
   962           }
   963         }
   965         // An allocation may have an Initialize which has raw stores. Scan
   966         // the users of the raw allocation result and push AddP users
   967         // on alloc_worklist.
   968         Node *raw_result = alloc->proj_out(TypeFunc::Parms);
   969         assert (raw_result != NULL, "must have an allocation result");
   970         for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
   971           Node *use = raw_result->fast_out(i);
   972           if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
   973             Node* addp2 = find_second_addp(use, raw_result);
   974             if (addp2 != NULL) {
   975               assert(alloc->is_AllocateArray(),"array allocation was expected");
   976               alloc_worklist.append_if_missing(addp2);
   977             }
   978             alloc_worklist.append_if_missing(use);
   979           } else if (use->is_Initialize()) {
   980             memnode_worklist.append_if_missing(use);
   981           }
   982         }
   983       }
   984     } else if (n->is_AddP()) {
   985       ptset.Clear();
   986       PointsTo(ptset, get_addp_base(n), igvn);
   987       assert(ptset.Size() == 1, "AddP address is unique");
   988       uint elem = ptset.getelem(); // Allocation node's index
   989       if (elem == _phantom_object)
   990         continue; // Assume the value was set outside this method.
   991       Node *base = get_map(elem);  // CheckCastPP node
   992       if (!split_AddP(n, base, igvn)) continue; // wrong type
   993       tinst = igvn->type(base)->isa_oopptr();
   994     } else if (n->is_Phi() ||
   995                n->is_CheckCastPP() ||
   996                n->is_EncodeP() ||
   997                n->is_DecodeN() ||
   998                (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
   999       if (visited.test_set(n->_idx)) {
  1000         assert(n->is_Phi(), "loops only through Phi's");
  1001         continue;  // already processed
  1003       ptset.Clear();
  1004       PointsTo(ptset, n, igvn);
  1005       if (ptset.Size() == 1) {
  1006         uint elem = ptset.getelem(); // Allocation node's index
  1007         if (elem == _phantom_object)
  1008           continue; // Assume the value was set outside this method.
  1009         Node *val = get_map(elem);   // CheckCastPP node
  1010         TypeNode *tn = n->as_Type();
  1011         tinst = igvn->type(val)->isa_oopptr();
  1012         assert(tinst != NULL && tinst->is_known_instance() &&
  1013                (uint)tinst->instance_id() == elem , "instance type expected.");
  1015         const Type *tn_type = igvn->type(tn);
  1016         const TypeOopPtr *tn_t;
  1017         if (tn_type->isa_narrowoop()) {
  1018           tn_t = tn_type->make_ptr()->isa_oopptr();
  1019         } else {
  1020           tn_t = tn_type->isa_oopptr();
  1023         if (tn_t != NULL &&
  1024             tinst->cast_to_instance_id(TypeOopPtr::InstanceBot)->higher_equal(tn_t)) {
  1025           if (tn_type->isa_narrowoop()) {
  1026             tn_type = tinst->make_narrowoop();
  1027           } else {
  1028             tn_type = tinst;
  1030           igvn->hash_delete(tn);
  1031           igvn->set_type(tn, tn_type);
  1032           tn->set_type(tn_type);
  1033           igvn->hash_insert(tn);
  1034           record_for_optimizer(n);
  1035         } else {
  1036           continue; // wrong type
  1039     } else {
  1040       continue;
  1042     // push users on appropriate worklist
  1043     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1044       Node *use = n->fast_out(i);
  1045       if(use->is_Mem() && use->in(MemNode::Address) == n) {
  1046         memnode_worklist.append_if_missing(use);
  1047       } else if (use->is_Initialize()) {
  1048         memnode_worklist.append_if_missing(use);
  1049       } else if (use->is_MergeMem()) {
  1050         mergemem_worklist.append_if_missing(use);
  1051       } else if (use->is_SafePoint() && tinst != NULL) {
  1052         // Look for MergeMem nodes for calls which reference unique allocation
  1053         // (through CheckCastPP nodes) even for debug info.
  1054         Node* m = use->in(TypeFunc::Memory);
  1055         uint iid = tinst->instance_id();
  1056         while (m->is_Proj() && m->in(0)->is_SafePoint() &&
  1057                m->in(0) != use && !m->in(0)->_idx != iid) {
  1058           m = m->in(0)->in(TypeFunc::Memory);
  1060         if (m->is_MergeMem()) {
  1061           mergemem_worklist.append_if_missing(m);
  1063       } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
  1064         Node* addp2 = find_second_addp(use, n);
  1065         if (addp2 != NULL) {
  1066           alloc_worklist.append_if_missing(addp2);
  1068         alloc_worklist.append_if_missing(use);
  1069       } else if (use->is_Phi() ||
  1070                  use->is_CheckCastPP() ||
  1071                  use->is_EncodeP() ||
  1072                  use->is_DecodeN() ||
  1073                  (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
  1074         alloc_worklist.append_if_missing(use);
  1079   // New alias types were created in split_AddP().
  1080   uint new_index_end = (uint) _compile->num_alias_types();
  1082   //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
  1083   //            compute new values for Memory inputs  (the Memory inputs are not
  1084   //            actually updated until phase 4.)
  1085   if (memnode_worklist.length() == 0)
  1086     return;  // nothing to do
  1088   while (memnode_worklist.length() != 0) {
  1089     Node *n = memnode_worklist.pop();
  1090     if (visited.test_set(n->_idx))
  1091       continue;
  1092     if (n->is_Phi()) {
  1093       assert(n->as_Phi()->adr_type() != TypePtr::BOTTOM, "narrow memory slice required");
  1094       // we don't need to do anything, but the users must be pushed if we haven't processed
  1095       // this Phi before
  1096     } else if (n->is_Initialize()) {
  1097       // we don't need to do anything, but the users of the memory projection must be pushed
  1098       n = n->as_Initialize()->proj_out(TypeFunc::Memory);
  1099       if (n == NULL)
  1100         continue;
  1101     } else {
  1102       assert(n->is_Mem(), "memory node required.");
  1103       Node *addr = n->in(MemNode::Address);
  1104       assert(addr->is_AddP(), "AddP required");
  1105       const Type *addr_t = igvn->type(addr);
  1106       if (addr_t == Type::TOP)
  1107         continue;
  1108       assert (addr_t->isa_ptr() != NULL, "pointer type required.");
  1109       int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
  1110       assert ((uint)alias_idx < new_index_end, "wrong alias index");
  1111       Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn);
  1112       if (_compile->failing()) {
  1113         return;
  1115       if (mem != n->in(MemNode::Memory)) {
  1116         set_map(n->_idx, mem);
  1117         ptnode_adr(n->_idx)->_node = n;
  1119       if (n->is_Load()) {
  1120         continue;  // don't push users
  1121       } else if (n->is_LoadStore()) {
  1122         // get the memory projection
  1123         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1124           Node *use = n->fast_out(i);
  1125           if (use->Opcode() == Op_SCMemProj) {
  1126             n = use;
  1127             break;
  1130         assert(n->Opcode() == Op_SCMemProj, "memory projection required");
  1133     // push user on appropriate worklist
  1134     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1135       Node *use = n->fast_out(i);
  1136       if (use->is_Phi()) {
  1137         memnode_worklist.append_if_missing(use);
  1138       } else if(use->is_Mem() && use->in(MemNode::Memory) == n) {
  1139         memnode_worklist.append_if_missing(use);
  1140       } else if (use->is_Initialize()) {
  1141         memnode_worklist.append_if_missing(use);
  1142       } else if (use->is_MergeMem()) {
  1143         mergemem_worklist.append_if_missing(use);
  1148   //  Phase 3:  Process MergeMem nodes from mergemem_worklist.
  1149   //            Walk each memory moving the first node encountered of each
  1150   //            instance type to the the input corresponding to its alias index.
  1151   while (mergemem_worklist.length() != 0) {
  1152     Node *n = mergemem_worklist.pop();
  1153     assert(n->is_MergeMem(), "MergeMem node required.");
  1154     if (visited.test_set(n->_idx))
  1155       continue;
  1156     MergeMemNode *nmm = n->as_MergeMem();
  1157     // Note: we don't want to use MergeMemStream here because we only want to
  1158     //  scan inputs which exist at the start, not ones we add during processing.
  1159     uint nslices = nmm->req();
  1160     igvn->hash_delete(nmm);
  1161     for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
  1162       Node* mem = nmm->in(i);
  1163       Node* cur = NULL;
  1164       if (mem == NULL || mem->is_top())
  1165         continue;
  1166       while (mem->is_Mem()) {
  1167         const Type *at = igvn->type(mem->in(MemNode::Address));
  1168         if (at != Type::TOP) {
  1169           assert (at->isa_ptr() != NULL, "pointer type required.");
  1170           uint idx = (uint)_compile->get_alias_index(at->is_ptr());
  1171           if (idx == i) {
  1172             if (cur == NULL)
  1173               cur = mem;
  1174           } else {
  1175             if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
  1176               nmm->set_memory_at(idx, mem);
  1180         mem = mem->in(MemNode::Memory);
  1182       nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
  1183       // Find any instance of the current type if we haven't encountered
  1184       // a value of the instance along the chain.
  1185       for (uint ni = new_index_start; ni < new_index_end; ni++) {
  1186         if((uint)_compile->get_general_index(ni) == i) {
  1187           Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
  1188           if (nmm->is_empty_memory(m)) {
  1189             Node* result = find_inst_mem(mem, ni, orig_phis, igvn);
  1190             if (_compile->failing()) {
  1191               return;
  1193             nmm->set_memory_at(ni, result);
  1198     // Find the rest of instances values
  1199     for (uint ni = new_index_start; ni < new_index_end; ni++) {
  1200       const TypeOopPtr *tinst = igvn->C->get_adr_type(ni)->isa_oopptr();
  1201       Node* result = step_through_mergemem(nmm, ni, tinst);
  1202       if (result == nmm->base_memory()) {
  1203         // Didn't find instance memory, search through general slice recursively.
  1204         result = nmm->memory_at(igvn->C->get_general_index(ni));
  1205         result = find_inst_mem(result, ni, orig_phis, igvn);
  1206         if (_compile->failing()) {
  1207           return;
  1209         nmm->set_memory_at(ni, result);
  1212     igvn->hash_insert(nmm);
  1213     record_for_optimizer(nmm);
  1215     // Propagate new memory slices to following MergeMem nodes.
  1216     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1217       Node *use = n->fast_out(i);
  1218       if (use->is_Call()) {
  1219         CallNode* in = use->as_Call();
  1220         if (in->proj_out(TypeFunc::Memory) != NULL) {
  1221           Node* m = in->proj_out(TypeFunc::Memory);
  1222           for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
  1223             Node* mm = m->fast_out(j);
  1224             if (mm->is_MergeMem()) {
  1225               mergemem_worklist.append_if_missing(mm);
  1229         if (use->is_Allocate()) {
  1230           use = use->as_Allocate()->initialization();
  1231           if (use == NULL) {
  1232             continue;
  1236       if (use->is_Initialize()) {
  1237         InitializeNode* in = use->as_Initialize();
  1238         if (in->proj_out(TypeFunc::Memory) != NULL) {
  1239           Node* m = in->proj_out(TypeFunc::Memory);
  1240           for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) {
  1241             Node* mm = m->fast_out(j);
  1242             if (mm->is_MergeMem()) {
  1243               mergemem_worklist.append_if_missing(mm);
  1251   //  Phase 4:  Update the inputs of non-instance memory Phis and
  1252   //            the Memory input of memnodes
  1253   // First update the inputs of any non-instance Phi's from
  1254   // which we split out an instance Phi.  Note we don't have
  1255   // to recursively process Phi's encounted on the input memory
  1256   // chains as is done in split_memory_phi() since they  will
  1257   // also be processed here.
  1258   for (int j = 0; j < orig_phis.length(); j++) {
  1259     PhiNode *phi = orig_phis.at(j);
  1260     int alias_idx = _compile->get_alias_index(phi->adr_type());
  1261     igvn->hash_delete(phi);
  1262     for (uint i = 1; i < phi->req(); i++) {
  1263       Node *mem = phi->in(i);
  1264       Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn);
  1265       if (_compile->failing()) {
  1266         return;
  1268       if (mem != new_mem) {
  1269         phi->set_req(i, new_mem);
  1272     igvn->hash_insert(phi);
  1273     record_for_optimizer(phi);
  1276   // Update the memory inputs of MemNodes with the value we computed
  1277   // in Phase 2.
  1278   for (uint i = 0; i < nodes_size(); i++) {
  1279     Node *nmem = get_map(i);
  1280     if (nmem != NULL) {
  1281       Node *n = ptnode_adr(i)->_node;
  1282       if (n != NULL && n->is_Mem()) {
  1283         igvn->hash_delete(n);
  1284         n->set_req(MemNode::Memory, nmem);
  1285         igvn->hash_insert(n);
  1286         record_for_optimizer(n);
  1292 bool ConnectionGraph::has_candidates(Compile *C) {
  1293   // EA brings benefits only when the code has allocations and/or locks which
  1294   // are represented by ideal Macro nodes.
  1295   int cnt = C->macro_count();
  1296   for( int i=0; i < cnt; i++ ) {
  1297     Node *n = C->macro_node(i);
  1298     if ( n->is_Allocate() )
  1299       return true;
  1300     if( n->is_Lock() ) {
  1301       Node* obj = n->as_Lock()->obj_node()->uncast();
  1302       if( !(obj->is_Parm() || obj->is_Con()) )
  1303         return true;
  1306   return false;
  1309 bool ConnectionGraph::compute_escape() {
  1310   Compile* C = _compile;
  1312   // 1. Populate Connection Graph (CG) with Ideal nodes.
  1314   Unique_Node_List worklist_init;
  1315   worklist_init.map(C->unique(), NULL);  // preallocate space
  1317   // Initialize worklist
  1318   if (C->root() != NULL) {
  1319     worklist_init.push(C->root());
  1322   GrowableArray<int> cg_worklist;
  1323   PhaseGVN* igvn = C->initial_gvn();
  1324   bool has_allocations = false;
  1326   // Push all useful nodes onto CG list and set their type.
  1327   for( uint next = 0; next < worklist_init.size(); ++next ) {
  1328     Node* n = worklist_init.at(next);
  1329     record_for_escape_analysis(n, igvn);
  1330     // Only allocations and java static calls results are checked
  1331     // for an escape status. See process_call_result() below.
  1332     if (n->is_Allocate() || n->is_CallStaticJava() &&
  1333         ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) {
  1334       has_allocations = true;
  1336     if(n->is_AddP())
  1337       cg_worklist.append(n->_idx);
  1338     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1339       Node* m = n->fast_out(i);   // Get user
  1340       worklist_init.push(m);
  1344   if (!has_allocations) {
  1345     _collecting = false;
  1346     return false; // Nothing to do.
  1349   // 2. First pass to create simple CG edges (doesn't require to walk CG).
  1350   uint delayed_size = _delayed_worklist.size();
  1351   for( uint next = 0; next < delayed_size; ++next ) {
  1352     Node* n = _delayed_worklist.at(next);
  1353     build_connection_graph(n, igvn);
  1356   // 3. Pass to create fields edges (Allocate -F-> AddP).
  1357   uint cg_length = cg_worklist.length();
  1358   for( uint next = 0; next < cg_length; ++next ) {
  1359     int ni = cg_worklist.at(next);
  1360     build_connection_graph(ptnode_adr(ni)->_node, igvn);
  1363   cg_worklist.clear();
  1364   cg_worklist.append(_phantom_object);
  1366   // 4. Build Connection Graph which need
  1367   //    to walk the connection graph.
  1368   for (uint ni = 0; ni < nodes_size(); ni++) {
  1369     PointsToNode* ptn = ptnode_adr(ni);
  1370     Node *n = ptn->_node;
  1371     if (n != NULL) { // Call, AddP, LoadP, StoreP
  1372       build_connection_graph(n, igvn);
  1373       if (ptn->node_type() != PointsToNode::UnknownType)
  1374         cg_worklist.append(n->_idx); // Collect CG nodes
  1378   VectorSet ptset(Thread::current()->resource_area());
  1379   GrowableArray<uint>  deferred_edges;
  1380   VectorSet visited(Thread::current()->resource_area());
  1382   // 5. Remove deferred edges from the graph and collect
  1383   //    information needed for type splitting.
  1384   cg_length = cg_worklist.length();
  1385   for( uint next = 0; next < cg_length; ++next ) {
  1386     int ni = cg_worklist.at(next);
  1387     PointsToNode* ptn = ptnode_adr(ni);
  1388     PointsToNode::NodeType nt = ptn->node_type();
  1389     if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) {
  1390       remove_deferred(ni, &deferred_edges, &visited);
  1391       Node *n = ptn->_node;
  1392       if (n->is_AddP()) {
  1393         // Search for objects which are not scalar replaceable.
  1394         // Mark their escape state as ArgEscape to propagate the state
  1395         // to referenced objects.
  1396         // Note: currently there are no difference in compiler optimizations
  1397         // for ArgEscape objects and NoEscape objects which are not
  1398         // scalar replaceable.
  1400         int offset = ptn->offset();
  1401         Node *base = get_addp_base(n);
  1402         ptset.Clear();
  1403         PointsTo(ptset, base, igvn);
  1404         int ptset_size = ptset.Size();
  1406         // Check if a field's initializing value is recorded and add
  1407         // a corresponding NULL field's value if it is not recorded.
  1408         // Connection Graph does not record a default initialization by NULL
  1409         // captured by Initialize node.
  1410         //
  1411         // Note: it will disable scalar replacement in some cases:
  1412         //
  1413         //    Point p[] = new Point[1];
  1414         //    p[0] = new Point(); // Will be not scalar replaced
  1415         //
  1416         // but it will save us from incorrect optimizations in next cases:
  1417         //
  1418         //    Point p[] = new Point[1];
  1419         //    if ( x ) p[0] = new Point(); // Will be not scalar replaced
  1420         //
  1421         // Without a control flow analysis we can't distinguish above cases.
  1422         //
  1423         if (offset != Type::OffsetBot && ptset_size == 1) {
  1424           uint elem = ptset.getelem(); // Allocation node's index
  1425           // It does not matter if it is not Allocation node since
  1426           // only non-escaping allocations are scalar replaced.
  1427           if (ptnode_adr(elem)->_node->is_Allocate() &&
  1428               ptnode_adr(elem)->escape_state() == PointsToNode::NoEscape) {
  1429             AllocateNode* alloc = ptnode_adr(elem)->_node->as_Allocate();
  1430             InitializeNode* ini = alloc->initialization();
  1431             Node* value = NULL;
  1432             if (ini != NULL) {
  1433               BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT;
  1434               Node* store = ini->find_captured_store(offset, type2aelembytes(ft), igvn);
  1435               if (store != NULL && store->is_Store())
  1436                 value = store->in(MemNode::ValueIn);
  1438             if (value == NULL || value != ptnode_adr(value->_idx)->_node) {
  1439               // A field's initializing value was not recorded. Add NULL.
  1440               uint null_idx = UseCompressedOops ? _noop_null : _oop_null;
  1441               add_pointsto_edge(ni, null_idx);
  1446         // An object is not scalar replaceable if the field which may point
  1447         // to it has unknown offset (unknown element of an array of objects).
  1448         //
  1449         if (offset == Type::OffsetBot) {
  1450           uint e_cnt = ptn->edge_count();
  1451           for (uint ei = 0; ei < e_cnt; ei++) {
  1452             uint npi = ptn->edge_target(ei);
  1453             set_escape_state(npi, PointsToNode::ArgEscape);
  1454             ptnode_adr(npi)->_scalar_replaceable = false;
  1458         // Currently an object is not scalar replaceable if a LoadStore node
  1459         // access its field since the field value is unknown after it.
  1460         //
  1461         bool has_LoadStore = false;
  1462         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1463           Node *use = n->fast_out(i);
  1464           if (use->is_LoadStore()) {
  1465             has_LoadStore = true;
  1466             break;
  1469         // An object is not scalar replaceable if the address points
  1470         // to unknown field (unknown element for arrays, offset is OffsetBot).
  1471         //
  1472         // Or the address may point to more then one object. This may produce
  1473         // the false positive result (set scalar_replaceable to false)
  1474         // since the flow-insensitive escape analysis can't separate
  1475         // the case when stores overwrite the field's value from the case
  1476         // when stores happened on different control branches.
  1477         //
  1478         if (ptset_size > 1 || ptset_size != 0 &&
  1479             (has_LoadStore || offset == Type::OffsetBot)) {
  1480           for( VectorSetI j(&ptset); j.test(); ++j ) {
  1481             set_escape_state(j.elem, PointsToNode::ArgEscape);
  1482             ptnode_adr(j.elem)->_scalar_replaceable = false;
  1489   // 6. Propagate escape states.
  1490   GrowableArray<int>  worklist;
  1491   bool has_non_escaping_obj = false;
  1493   // push all GlobalEscape nodes on the worklist
  1494   for( uint next = 0; next < cg_length; ++next ) {
  1495     int nk = cg_worklist.at(next);
  1496     if (ptnode_adr(nk)->escape_state() == PointsToNode::GlobalEscape)
  1497       worklist.push(nk);
  1499   // mark all nodes reachable from GlobalEscape nodes
  1500   while(worklist.length() > 0) {
  1501     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1502     uint e_cnt = ptn->edge_count();
  1503     for (uint ei = 0; ei < e_cnt; ei++) {
  1504       uint npi = ptn->edge_target(ei);
  1505       PointsToNode *np = ptnode_adr(npi);
  1506       if (np->escape_state() < PointsToNode::GlobalEscape) {
  1507         np->set_escape_state(PointsToNode::GlobalEscape);
  1508         worklist.push(npi);
  1513   // push all ArgEscape nodes on the worklist
  1514   for( uint next = 0; next < cg_length; ++next ) {
  1515     int nk = cg_worklist.at(next);
  1516     if (ptnode_adr(nk)->escape_state() == PointsToNode::ArgEscape)
  1517       worklist.push(nk);
  1519   // mark all nodes reachable from ArgEscape nodes
  1520   while(worklist.length() > 0) {
  1521     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1522     if (ptn->node_type() == PointsToNode::JavaObject)
  1523       has_non_escaping_obj = true; // Non GlobalEscape
  1524     uint e_cnt = ptn->edge_count();
  1525     for (uint ei = 0; ei < e_cnt; ei++) {
  1526       uint npi = ptn->edge_target(ei);
  1527       PointsToNode *np = ptnode_adr(npi);
  1528       if (np->escape_state() < PointsToNode::ArgEscape) {
  1529         np->set_escape_state(PointsToNode::ArgEscape);
  1530         worklist.push(npi);
  1535   GrowableArray<Node*> alloc_worklist;
  1537   // push all NoEscape nodes on the worklist
  1538   for( uint next = 0; next < cg_length; ++next ) {
  1539     int nk = cg_worklist.at(next);
  1540     if (ptnode_adr(nk)->escape_state() == PointsToNode::NoEscape)
  1541       worklist.push(nk);
  1543   // mark all nodes reachable from NoEscape nodes
  1544   while(worklist.length() > 0) {
  1545     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1546     if (ptn->node_type() == PointsToNode::JavaObject)
  1547       has_non_escaping_obj = true; // Non GlobalEscape
  1548     Node* n = ptn->_node;
  1549     if (n->is_Allocate() && ptn->_scalar_replaceable ) {
  1550       // Push scalar replaceable alocations on alloc_worklist
  1551       // for processing in split_unique_types().
  1552       alloc_worklist.append(n);
  1554     uint e_cnt = ptn->edge_count();
  1555     for (uint ei = 0; ei < e_cnt; ei++) {
  1556       uint npi = ptn->edge_target(ei);
  1557       PointsToNode *np = ptnode_adr(npi);
  1558       if (np->escape_state() < PointsToNode::NoEscape) {
  1559         np->set_escape_state(PointsToNode::NoEscape);
  1560         worklist.push(npi);
  1565   _collecting = false;
  1566   assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build");
  1568   bool has_scalar_replaceable_candidates = alloc_worklist.length() > 0;
  1569   if ( has_scalar_replaceable_candidates &&
  1570        C->AliasLevel() >= 3 && EliminateAllocations ) {
  1572     // Now use the escape information to create unique types for
  1573     // scalar replaceable objects.
  1574     split_unique_types(alloc_worklist);
  1576     if (C->failing())  return false;
  1578     // Clean up after split unique types.
  1579     ResourceMark rm;
  1580     PhaseRemoveUseless pru(C->initial_gvn(), C->for_igvn());
  1582     C->print_method("After Escape Analysis", 2);
  1584 #ifdef ASSERT
  1585   } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
  1586     tty->print("=== No allocations eliminated for ");
  1587     C->method()->print_short_name();
  1588     if(!EliminateAllocations) {
  1589       tty->print(" since EliminateAllocations is off ===");
  1590     } else if(!has_scalar_replaceable_candidates) {
  1591       tty->print(" since there are no scalar replaceable candidates ===");
  1592     } else if(C->AliasLevel() < 3) {
  1593       tty->print(" since AliasLevel < 3 ===");
  1595     tty->cr();
  1596 #endif
  1598   return has_non_escaping_obj;
  1601 void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) {
  1603     switch (call->Opcode()) {
  1604 #ifdef ASSERT
  1605     case Op_Allocate:
  1606     case Op_AllocateArray:
  1607     case Op_Lock:
  1608     case Op_Unlock:
  1609       assert(false, "should be done already");
  1610       break;
  1611 #endif
  1612     case Op_CallLeafNoFP:
  1614       // Stub calls, objects do not escape but they are not scale replaceable.
  1615       // Adjust escape state for outgoing arguments.
  1616       const TypeTuple * d = call->tf()->domain();
  1617       VectorSet ptset(Thread::current()->resource_area());
  1618       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1619         const Type* at = d->field_at(i);
  1620         Node *arg = call->in(i)->uncast();
  1621         const Type *aat = phase->type(arg);
  1622         if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr()) {
  1623           assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
  1624                  aat->isa_ptr() != NULL, "expecting an Ptr");
  1625           set_escape_state(arg->_idx, PointsToNode::ArgEscape);
  1626           if (arg->is_AddP()) {
  1627             //
  1628             // The inline_native_clone() case when the arraycopy stub is called
  1629             // after the allocation before Initialize and CheckCastPP nodes.
  1630             //
  1631             // Set AddP's base (Allocate) as not scalar replaceable since
  1632             // pointer to the base (with offset) is passed as argument.
  1633             //
  1634             arg = get_addp_base(arg);
  1636           ptset.Clear();
  1637           PointsTo(ptset, arg, phase);
  1638           for( VectorSetI j(&ptset); j.test(); ++j ) {
  1639             uint pt = j.elem;
  1640             set_escape_state(pt, PointsToNode::ArgEscape);
  1644       break;
  1647     case Op_CallStaticJava:
  1648     // For a static call, we know exactly what method is being called.
  1649     // Use bytecode estimator to record the call's escape affects
  1651       ciMethod *meth = call->as_CallJava()->method();
  1652       BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
  1653       // fall-through if not a Java method or no analyzer information
  1654       if (call_analyzer != NULL) {
  1655         const TypeTuple * d = call->tf()->domain();
  1656         VectorSet ptset(Thread::current()->resource_area());
  1657         bool copy_dependencies = false;
  1658         for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1659           const Type* at = d->field_at(i);
  1660           int k = i - TypeFunc::Parms;
  1662           if (at->isa_oopptr() != NULL) {
  1663             Node *arg = call->in(i)->uncast();
  1665             bool global_escapes = false;
  1666             bool fields_escapes = false;
  1667             if (!call_analyzer->is_arg_stack(k)) {
  1668               // The argument global escapes, mark everything it could point to
  1669               set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
  1670               global_escapes = true;
  1671             } else {
  1672               if (!call_analyzer->is_arg_local(k)) {
  1673                 // The argument itself doesn't escape, but any fields might
  1674                 fields_escapes = true;
  1676               set_escape_state(arg->_idx, PointsToNode::ArgEscape);
  1677               copy_dependencies = true;
  1680             ptset.Clear();
  1681             PointsTo(ptset, arg, phase);
  1682             for( VectorSetI j(&ptset); j.test(); ++j ) {
  1683               uint pt = j.elem;
  1684               if (global_escapes) {
  1685                 //The argument global escapes, mark everything it could point to
  1686                 set_escape_state(pt, PointsToNode::GlobalEscape);
  1687               } else {
  1688                 if (fields_escapes) {
  1689                   // The argument itself doesn't escape, but any fields might
  1690                   add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
  1692                 set_escape_state(pt, PointsToNode::ArgEscape);
  1697         if (copy_dependencies)
  1698           call_analyzer->copy_dependencies(_compile->dependencies());
  1699         break;
  1703     default:
  1704     // Fall-through here if not a Java method or no analyzer information
  1705     // or some other type of call, assume the worst case: all arguments
  1706     // globally escape.
  1708       // adjust escape state for  outgoing arguments
  1709       const TypeTuple * d = call->tf()->domain();
  1710       VectorSet ptset(Thread::current()->resource_area());
  1711       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1712         const Type* at = d->field_at(i);
  1713         if (at->isa_oopptr() != NULL) {
  1714           Node *arg = call->in(i)->uncast();
  1715           set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
  1716           ptset.Clear();
  1717           PointsTo(ptset, arg, phase);
  1718           for( VectorSetI j(&ptset); j.test(); ++j ) {
  1719             uint pt = j.elem;
  1720             set_escape_state(pt, PointsToNode::GlobalEscape);
  1727 void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) {
  1728   CallNode   *call = resproj->in(0)->as_Call();
  1729   uint    call_idx = call->_idx;
  1730   uint resproj_idx = resproj->_idx;
  1732   switch (call->Opcode()) {
  1733     case Op_Allocate:
  1735       Node *k = call->in(AllocateNode::KlassNode);
  1736       const TypeKlassPtr *kt;
  1737       if (k->Opcode() == Op_LoadKlass) {
  1738         kt = k->as_Load()->type()->isa_klassptr();
  1739       } else {
  1740         // Also works for DecodeN(LoadNKlass).
  1741         kt = k->as_Type()->type()->isa_klassptr();
  1743       assert(kt != NULL, "TypeKlassPtr  required.");
  1744       ciKlass* cik = kt->klass();
  1745       ciInstanceKlass* ciik = cik->as_instance_klass();
  1747       PointsToNode::EscapeState es;
  1748       uint edge_to;
  1749       if (cik->is_subclass_of(_compile->env()->Thread_klass()) || ciik->has_finalizer()) {
  1750         es = PointsToNode::GlobalEscape;
  1751         edge_to = _phantom_object; // Could not be worse
  1752       } else {
  1753         es = PointsToNode::NoEscape;
  1754         edge_to = call_idx;
  1756       set_escape_state(call_idx, es);
  1757       add_pointsto_edge(resproj_idx, edge_to);
  1758       _processed.set(resproj_idx);
  1759       break;
  1762     case Op_AllocateArray:
  1764       int length = call->in(AllocateNode::ALength)->find_int_con(-1);
  1765       if (length < 0 || length > EliminateAllocationArraySizeLimit) {
  1766         // Not scalar replaceable if the length is not constant or too big.
  1767         ptnode_adr(call_idx)->_scalar_replaceable = false;
  1769       set_escape_state(call_idx, PointsToNode::NoEscape);
  1770       add_pointsto_edge(resproj_idx, call_idx);
  1771       _processed.set(resproj_idx);
  1772       break;
  1775     case Op_CallStaticJava:
  1776     // For a static call, we know exactly what method is being called.
  1777     // Use bytecode estimator to record whether the call's return value escapes
  1779       bool done = true;
  1780       const TypeTuple *r = call->tf()->range();
  1781       const Type* ret_type = NULL;
  1783       if (r->cnt() > TypeFunc::Parms)
  1784         ret_type = r->field_at(TypeFunc::Parms);
  1786       // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
  1787       //        _multianewarray functions return a TypeRawPtr.
  1788       if (ret_type == NULL || ret_type->isa_ptr() == NULL) {
  1789         _processed.set(resproj_idx);
  1790         break;  // doesn't return a pointer type
  1792       ciMethod *meth = call->as_CallJava()->method();
  1793       const TypeTuple * d = call->tf()->domain();
  1794       if (meth == NULL) {
  1795         // not a Java method, assume global escape
  1796         set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1797         add_pointsto_edge(resproj_idx, _phantom_object);
  1798       } else {
  1799         BCEscapeAnalyzer *call_analyzer = meth->get_bcea();
  1800         bool copy_dependencies = false;
  1802         if (call_analyzer->is_return_allocated()) {
  1803           // Returns a newly allocated unescaped object, simply
  1804           // update dependency information.
  1805           // Mark it as NoEscape so that objects referenced by
  1806           // it's fields will be marked as NoEscape at least.
  1807           set_escape_state(call_idx, PointsToNode::NoEscape);
  1808           add_pointsto_edge(resproj_idx, call_idx);
  1809           copy_dependencies = true;
  1810         } else if (call_analyzer->is_return_local()) {
  1811           // determine whether any arguments are returned
  1812           set_escape_state(call_idx, PointsToNode::NoEscape);
  1813           bool ret_arg = false;
  1814           for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1815             const Type* at = d->field_at(i);
  1817             if (at->isa_oopptr() != NULL) {
  1818               Node *arg = call->in(i)->uncast();
  1820               if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
  1821                 ret_arg = true;
  1822                 PointsToNode *arg_esp = ptnode_adr(arg->_idx);
  1823                 if (arg_esp->node_type() == PointsToNode::UnknownType)
  1824                   done = false;
  1825                 else if (arg_esp->node_type() == PointsToNode::JavaObject)
  1826                   add_pointsto_edge(resproj_idx, arg->_idx);
  1827                 else
  1828                   add_deferred_edge(resproj_idx, arg->_idx);
  1829                 arg_esp->_hidden_alias = true;
  1833           if (done && !ret_arg) {
  1834             // Returns unknown object.
  1835             set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1836             add_pointsto_edge(resproj_idx, _phantom_object);
  1838           copy_dependencies = true;
  1839         } else {
  1840           set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1841           add_pointsto_edge(resproj_idx, _phantom_object);
  1842           for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1843             const Type* at = d->field_at(i);
  1844             if (at->isa_oopptr() != NULL) {
  1845               Node *arg = call->in(i)->uncast();
  1846               PointsToNode *arg_esp = ptnode_adr(arg->_idx);
  1847               arg_esp->_hidden_alias = true;
  1851         if (copy_dependencies)
  1852           call_analyzer->copy_dependencies(_compile->dependencies());
  1854       if (done)
  1855         _processed.set(resproj_idx);
  1856       break;
  1859     default:
  1860     // Some other type of call, assume the worst case that the
  1861     // returned value, if any, globally escapes.
  1863       const TypeTuple *r = call->tf()->range();
  1864       if (r->cnt() > TypeFunc::Parms) {
  1865         const Type* ret_type = r->field_at(TypeFunc::Parms);
  1867         // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
  1868         //        _multianewarray functions return a TypeRawPtr.
  1869         if (ret_type->isa_ptr() != NULL) {
  1870           set_escape_state(call_idx, PointsToNode::GlobalEscape);
  1871           add_pointsto_edge(resproj_idx, _phantom_object);
  1874       _processed.set(resproj_idx);
  1879 // Populate Connection Graph with Ideal nodes and create simple
  1880 // connection graph edges (do not need to check the node_type of inputs
  1881 // or to call PointsTo() to walk the connection graph).
  1882 void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) {
  1883   if (_processed.test(n->_idx))
  1884     return; // No need to redefine node's state.
  1886   if (n->is_Call()) {
  1887     // Arguments to allocation and locking don't escape.
  1888     if (n->is_Allocate()) {
  1889       add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true);
  1890       record_for_optimizer(n);
  1891     } else if (n->is_Lock() || n->is_Unlock()) {
  1892       // Put Lock and Unlock nodes on IGVN worklist to process them during
  1893       // the first IGVN optimization when escape information is still available.
  1894       record_for_optimizer(n);
  1895       _processed.set(n->_idx);
  1896     } else {
  1897       // Have to process call's arguments first.
  1898       PointsToNode::NodeType nt = PointsToNode::UnknownType;
  1900       // Check if a call returns an object.
  1901       const TypeTuple *r = n->as_Call()->tf()->range();
  1902       if (n->is_CallStaticJava() && r->cnt() > TypeFunc::Parms &&
  1903           n->as_Call()->proj_out(TypeFunc::Parms) != NULL) {
  1904         // Note:  use isa_ptr() instead of isa_oopptr() here because
  1905         //        the _multianewarray functions return a TypeRawPtr.
  1906         if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
  1907           nt = PointsToNode::JavaObject;
  1910       add_node(n, nt, PointsToNode::UnknownEscape, false);
  1912     return;
  1915   // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
  1916   // ThreadLocal has RawPrt type.
  1917   switch (n->Opcode()) {
  1918     case Op_AddP:
  1920       add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false);
  1921       break;
  1923     case Op_CastX2P:
  1924     { // "Unsafe" memory access.
  1925       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  1926       break;
  1928     case Op_CastPP:
  1929     case Op_CheckCastPP:
  1930     case Op_EncodeP:
  1931     case Op_DecodeN:
  1933       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  1934       int ti = n->in(1)->_idx;
  1935       PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  1936       if (nt == PointsToNode::UnknownType) {
  1937         _delayed_worklist.push(n); // Process it later.
  1938         break;
  1939       } else if (nt == PointsToNode::JavaObject) {
  1940         add_pointsto_edge(n->_idx, ti);
  1941       } else {
  1942         add_deferred_edge(n->_idx, ti);
  1944       _processed.set(n->_idx);
  1945       break;
  1947     case Op_ConP:
  1949       // assume all pointer constants globally escape except for null
  1950       PointsToNode::EscapeState es;
  1951       if (phase->type(n) == TypePtr::NULL_PTR)
  1952         es = PointsToNode::NoEscape;
  1953       else
  1954         es = PointsToNode::GlobalEscape;
  1956       add_node(n, PointsToNode::JavaObject, es, true);
  1957       break;
  1959     case Op_ConN:
  1961       // assume all narrow oop constants globally escape except for null
  1962       PointsToNode::EscapeState es;
  1963       if (phase->type(n) == TypeNarrowOop::NULL_PTR)
  1964         es = PointsToNode::NoEscape;
  1965       else
  1966         es = PointsToNode::GlobalEscape;
  1968       add_node(n, PointsToNode::JavaObject, es, true);
  1969       break;
  1971     case Op_CreateEx:
  1973       // assume that all exception objects globally escape
  1974       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  1975       break;
  1977     case Op_LoadKlass:
  1978     case Op_LoadNKlass:
  1980       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  1981       break;
  1983     case Op_LoadP:
  1984     case Op_LoadN:
  1986       const Type *t = phase->type(n);
  1987       if (t->make_ptr() == NULL) {
  1988         _processed.set(n->_idx);
  1989         return;
  1991       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  1992       break;
  1994     case Op_Parm:
  1996       _processed.set(n->_idx); // No need to redefine it state.
  1997       uint con = n->as_Proj()->_con;
  1998       if (con < TypeFunc::Parms)
  1999         return;
  2000       const Type *t = n->in(0)->as_Start()->_domain->field_at(con);
  2001       if (t->isa_ptr() == NULL)
  2002         return;
  2003       // We have to assume all input parameters globally escape
  2004       // (Note: passing 'false' since _processed is already set).
  2005       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false);
  2006       break;
  2008     case Op_Phi:
  2010       const Type *t = n->as_Phi()->type();
  2011       if (t->make_ptr() == NULL) {
  2012         // nothing to do if not an oop or narrow oop
  2013         _processed.set(n->_idx);
  2014         return;
  2016       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2017       uint i;
  2018       for (i = 1; i < n->req() ; i++) {
  2019         Node* in = n->in(i);
  2020         if (in == NULL)
  2021           continue;  // ignore NULL
  2022         in = in->uncast();
  2023         if (in->is_top() || in == n)
  2024           continue;  // ignore top or inputs which go back this node
  2025         int ti = in->_idx;
  2026         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2027         if (nt == PointsToNode::UnknownType) {
  2028           break;
  2029         } else if (nt == PointsToNode::JavaObject) {
  2030           add_pointsto_edge(n->_idx, ti);
  2031         } else {
  2032           add_deferred_edge(n->_idx, ti);
  2035       if (i >= n->req())
  2036         _processed.set(n->_idx);
  2037       else
  2038         _delayed_worklist.push(n);
  2039       break;
  2041     case Op_Proj:
  2043       // we are only interested in the result projection from a call
  2044       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
  2045         add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2046         process_call_result(n->as_Proj(), phase);
  2047         if (!_processed.test(n->_idx)) {
  2048           // The call's result may need to be processed later if the call
  2049           // returns it's argument and the argument is not processed yet.
  2050           _delayed_worklist.push(n);
  2052       } else {
  2053         _processed.set(n->_idx);
  2055       break;
  2057     case Op_Return:
  2059       if( n->req() > TypeFunc::Parms &&
  2060           phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
  2061         // Treat Return value as LocalVar with GlobalEscape escape state.
  2062         add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false);
  2063         int ti = n->in(TypeFunc::Parms)->_idx;
  2064         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2065         if (nt == PointsToNode::UnknownType) {
  2066           _delayed_worklist.push(n); // Process it later.
  2067           break;
  2068         } else if (nt == PointsToNode::JavaObject) {
  2069           add_pointsto_edge(n->_idx, ti);
  2070         } else {
  2071           add_deferred_edge(n->_idx, ti);
  2074       _processed.set(n->_idx);
  2075       break;
  2077     case Op_StoreP:
  2078     case Op_StoreN:
  2080       const Type *adr_type = phase->type(n->in(MemNode::Address));
  2081       adr_type = adr_type->make_ptr();
  2082       if (adr_type->isa_oopptr()) {
  2083         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2084       } else {
  2085         Node* adr = n->in(MemNode::Address);
  2086         if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL &&
  2087             adr->in(AddPNode::Address)->is_Proj() &&
  2088             adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
  2089           add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2090           // We are computing a raw address for a store captured
  2091           // by an Initialize compute an appropriate address type.
  2092           int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
  2093           assert(offs != Type::OffsetBot, "offset must be a constant");
  2094         } else {
  2095           _processed.set(n->_idx);
  2096           return;
  2099       break;
  2101     case Op_StorePConditional:
  2102     case Op_CompareAndSwapP:
  2103     case Op_CompareAndSwapN:
  2105       const Type *adr_type = phase->type(n->in(MemNode::Address));
  2106       adr_type = adr_type->make_ptr();
  2107       if (adr_type->isa_oopptr()) {
  2108         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2109       } else {
  2110         _processed.set(n->_idx);
  2111         return;
  2113       break;
  2115     case Op_ThreadLocal:
  2117       add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true);
  2118       break;
  2120     default:
  2122       // nothing to do
  2124   return;
  2127 void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) {
  2128   uint n_idx = n->_idx;
  2130   // Don't set processed bit for AddP, LoadP, StoreP since
  2131   // they may need more then one pass to process.
  2132   if (_processed.test(n_idx))
  2133     return; // No need to redefine node's state.
  2135   if (n->is_Call()) {
  2136     CallNode *call = n->as_Call();
  2137     process_call_arguments(call, phase);
  2138     _processed.set(n_idx);
  2139     return;
  2142   switch (n->Opcode()) {
  2143     case Op_AddP:
  2145       Node *base = get_addp_base(n);
  2146       // Create a field edge to this node from everything base could point to.
  2147       VectorSet ptset(Thread::current()->resource_area());
  2148       PointsTo(ptset, base, phase);
  2149       for( VectorSetI i(&ptset); i.test(); ++i ) {
  2150         uint pt = i.elem;
  2151         add_field_edge(pt, n_idx, address_offset(n, phase));
  2153       break;
  2155     case Op_CastX2P:
  2157       assert(false, "Op_CastX2P");
  2158       break;
  2160     case Op_CastPP:
  2161     case Op_CheckCastPP:
  2162     case Op_EncodeP:
  2163     case Op_DecodeN:
  2165       int ti = n->in(1)->_idx;
  2166       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
  2167         add_pointsto_edge(n_idx, ti);
  2168       } else {
  2169         add_deferred_edge(n_idx, ti);
  2171       _processed.set(n_idx);
  2172       break;
  2174     case Op_ConP:
  2176       assert(false, "Op_ConP");
  2177       break;
  2179     case Op_ConN:
  2181       assert(false, "Op_ConN");
  2182       break;
  2184     case Op_CreateEx:
  2186       assert(false, "Op_CreateEx");
  2187       break;
  2189     case Op_LoadKlass:
  2190     case Op_LoadNKlass:
  2192       assert(false, "Op_LoadKlass");
  2193       break;
  2195     case Op_LoadP:
  2196     case Op_LoadN:
  2198       const Type *t = phase->type(n);
  2199 #ifdef ASSERT
  2200       if (t->make_ptr() == NULL)
  2201         assert(false, "Op_LoadP");
  2202 #endif
  2204       Node* adr = n->in(MemNode::Address)->uncast();
  2205       const Type *adr_type = phase->type(adr);
  2206       Node* adr_base;
  2207       if (adr->is_AddP()) {
  2208         adr_base = get_addp_base(adr);
  2209       } else {
  2210         adr_base = adr;
  2213       // For everything "adr_base" could point to, create a deferred edge from
  2214       // this node to each field with the same offset.
  2215       VectorSet ptset(Thread::current()->resource_area());
  2216       PointsTo(ptset, adr_base, phase);
  2217       int offset = address_offset(adr, phase);
  2218       for( VectorSetI i(&ptset); i.test(); ++i ) {
  2219         uint pt = i.elem;
  2220         add_deferred_edge_to_fields(n_idx, pt, offset);
  2222       break;
  2224     case Op_Parm:
  2226       assert(false, "Op_Parm");
  2227       break;
  2229     case Op_Phi:
  2231 #ifdef ASSERT
  2232       const Type *t = n->as_Phi()->type();
  2233       if (t->make_ptr() == NULL)
  2234         assert(false, "Op_Phi");
  2235 #endif
  2236       for (uint i = 1; i < n->req() ; i++) {
  2237         Node* in = n->in(i);
  2238         if (in == NULL)
  2239           continue;  // ignore NULL
  2240         in = in->uncast();
  2241         if (in->is_top() || in == n)
  2242           continue;  // ignore top or inputs which go back this node
  2243         int ti = in->_idx;
  2244         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2245         assert(nt != PointsToNode::UnknownType, "all nodes should be known");
  2246         if (nt == PointsToNode::JavaObject) {
  2247           add_pointsto_edge(n_idx, ti);
  2248         } else {
  2249           add_deferred_edge(n_idx, ti);
  2252       _processed.set(n_idx);
  2253       break;
  2255     case Op_Proj:
  2257       // we are only interested in the result projection from a call
  2258       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
  2259         process_call_result(n->as_Proj(), phase);
  2260         assert(_processed.test(n_idx), "all call results should be processed");
  2261       } else {
  2262         assert(false, "Op_Proj");
  2264       break;
  2266     case Op_Return:
  2268 #ifdef ASSERT
  2269       if( n->req() <= TypeFunc::Parms ||
  2270           !phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
  2271         assert(false, "Op_Return");
  2273 #endif
  2274       int ti = n->in(TypeFunc::Parms)->_idx;
  2275       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
  2276         add_pointsto_edge(n_idx, ti);
  2277       } else {
  2278         add_deferred_edge(n_idx, ti);
  2280       _processed.set(n_idx);
  2281       break;
  2283     case Op_StoreP:
  2284     case Op_StoreN:
  2285     case Op_StorePConditional:
  2286     case Op_CompareAndSwapP:
  2287     case Op_CompareAndSwapN:
  2289       Node *adr = n->in(MemNode::Address);
  2290       const Type *adr_type = phase->type(adr)->make_ptr();
  2291 #ifdef ASSERT
  2292       if (!adr_type->isa_oopptr())
  2293         assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP");
  2294 #endif
  2296       assert(adr->is_AddP(), "expecting an AddP");
  2297       Node *adr_base = get_addp_base(adr);
  2298       Node *val = n->in(MemNode::ValueIn)->uncast();
  2299       // For everything "adr_base" could point to, create a deferred edge
  2300       // to "val" from each field with the same offset.
  2301       VectorSet ptset(Thread::current()->resource_area());
  2302       PointsTo(ptset, adr_base, phase);
  2303       for( VectorSetI i(&ptset); i.test(); ++i ) {
  2304         uint pt = i.elem;
  2305         add_edge_from_fields(pt, val->_idx, address_offset(adr, phase));
  2307       break;
  2309     case Op_ThreadLocal:
  2311       assert(false, "Op_ThreadLocal");
  2312       break;
  2314     default:
  2316       // nothing to do
  2320 #ifndef PRODUCT
  2321 void ConnectionGraph::dump() {
  2322   PhaseGVN  *igvn = _compile->initial_gvn();
  2323   bool first = true;
  2325   uint size = nodes_size();
  2326   for (uint ni = 0; ni < size; ni++) {
  2327     PointsToNode *ptn = ptnode_adr(ni);
  2328     PointsToNode::NodeType ptn_type = ptn->node_type();
  2330     if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL)
  2331       continue;
  2332     PointsToNode::EscapeState es = escape_state(ptn->_node, igvn);
  2333     if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) {
  2334       if (first) {
  2335         tty->cr();
  2336         tty->print("======== Connection graph for ");
  2337         _compile->method()->print_short_name();
  2338         tty->cr();
  2339         first = false;
  2341       tty->print("%6d ", ni);
  2342       ptn->dump();
  2343       // Print all locals which reference this allocation
  2344       for (uint li = ni; li < size; li++) {
  2345         PointsToNode *ptn_loc = ptnode_adr(li);
  2346         PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type();
  2347         if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL &&
  2348              ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) {
  2349           ptnode_adr(li)->dump(false);
  2352       if (Verbose) {
  2353         // Print all fields which reference this allocation
  2354         for (uint i = 0; i < ptn->edge_count(); i++) {
  2355           uint ei = ptn->edge_target(i);
  2356           ptnode_adr(ei)->dump(false);
  2359       tty->cr();
  2363 #endif

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