src/share/vm/opto/escape.cpp

Fri, 11 Mar 2011 07:50:51 -0800

author
kvn
date
Fri, 11 Mar 2011 07:50:51 -0800
changeset 2636
83f08886981c
parent 2556
3763ca6579b7
child 2741
55973726c600
permissions
-rw-r--r--

7026631: field _klass is incorrectly set for dual type of TypeAryPtr::OOPS
Summary: add missing check this->dual() != TypeAryPtr::OOPS into TypeAryPtr::klass().
Reviewed-by: never

     1 /*
     2  * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.
     8  *
     9  * This code is distributed in the hope that it will be useful, but WITHOUT
    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    12  * version 2 for more details (a copy is included in the LICENSE file that
    13  * accompanied this code).
    14  *
    15  * You should have received a copy of the GNU General Public License version
    16  * 2 along with this work; if not, write to the Free Software Foundation,
    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    18  *
    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    20  * or visit www.oracle.com if you need additional information or have any
    21  * questions.
    22  *
    23  */
    25 #include "precompiled.hpp"
    26 #include "ci/bcEscapeAnalyzer.hpp"
    27 #include "libadt/vectset.hpp"
    28 #include "memory/allocation.hpp"
    29 #include "opto/c2compiler.hpp"
    30 #include "opto/callnode.hpp"
    31 #include "opto/cfgnode.hpp"
    32 #include "opto/compile.hpp"
    33 #include "opto/escape.hpp"
    34 #include "opto/phaseX.hpp"
    35 #include "opto/rootnode.hpp"
    37 void PointsToNode::add_edge(uint targIdx, PointsToNode::EdgeType et) {
    38   uint v = (targIdx << EdgeShift) + ((uint) et);
    39   if (_edges == NULL) {
    40      Arena *a = Compile::current()->comp_arena();
    41     _edges = new(a) GrowableArray<uint>(a, INITIAL_EDGE_COUNT, 0, 0);
    42   }
    43   _edges->append_if_missing(v);
    44 }
    46 void PointsToNode::remove_edge(uint targIdx, PointsToNode::EdgeType et) {
    47   uint v = (targIdx << EdgeShift) + ((uint) et);
    49   _edges->remove(v);
    50 }
    52 #ifndef PRODUCT
    53 static const char *node_type_names[] = {
    54   "UnknownType",
    55   "JavaObject",
    56   "LocalVar",
    57   "Field"
    58 };
    60 static const char *esc_names[] = {
    61   "UnknownEscape",
    62   "NoEscape",
    63   "ArgEscape",
    64   "GlobalEscape"
    65 };
    67 static const char *edge_type_suffix[] = {
    68  "?", // UnknownEdge
    69  "P", // PointsToEdge
    70  "D", // DeferredEdge
    71  "F"  // FieldEdge
    72 };
    74 void PointsToNode::dump(bool print_state) const {
    75   NodeType nt = node_type();
    76   tty->print("%s ", node_type_names[(int) nt]);
    77   if (print_state) {
    78     EscapeState es = escape_state();
    79     tty->print("%s %s ", esc_names[(int) es], _scalar_replaceable ? "":"NSR");
    80   }
    81   tty->print("[[");
    82   for (uint i = 0; i < edge_count(); i++) {
    83     tty->print(" %d%s", edge_target(i), edge_type_suffix[(int) edge_type(i)]);
    84   }
    85   tty->print("]]  ");
    86   if (_node == NULL)
    87     tty->print_cr("<null>");
    88   else
    89     _node->dump();
    90 }
    91 #endif
    93 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) :
    94   _nodes(C->comp_arena(), C->unique(), C->unique(), PointsToNode()),
    95   _processed(C->comp_arena()),
    96   pt_ptset(C->comp_arena()),
    97   pt_visited(C->comp_arena()),
    98   pt_worklist(C->comp_arena(), 4, 0, 0),
    99   _collecting(true),
   100   _progress(false),
   101   _compile(C),
   102   _igvn(igvn),
   103   _node_map(C->comp_arena()) {
   105   _phantom_object = C->top()->_idx,
   106   add_node(C->top(), PointsToNode::JavaObject, PointsToNode::GlobalEscape,true);
   108   // Add ConP(#NULL) and ConN(#NULL) nodes.
   109   Node* oop_null = igvn->zerocon(T_OBJECT);
   110   _oop_null = oop_null->_idx;
   111   assert(_oop_null < C->unique(), "should be created already");
   112   add_node(oop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
   114   if (UseCompressedOops) {
   115     Node* noop_null = igvn->zerocon(T_NARROWOOP);
   116     _noop_null = noop_null->_idx;
   117     assert(_noop_null < C->unique(), "should be created already");
   118     add_node(noop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
   119   }
   120 }
   122 void ConnectionGraph::add_pointsto_edge(uint from_i, uint to_i) {
   123   PointsToNode *f = ptnode_adr(from_i);
   124   PointsToNode *t = ptnode_adr(to_i);
   126   assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
   127   assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of PointsTo edge");
   128   assert(t->node_type() == PointsToNode::JavaObject, "invalid destination of PointsTo edge");
   129   add_edge(f, to_i, PointsToNode::PointsToEdge);
   130 }
   132 void ConnectionGraph::add_deferred_edge(uint from_i, uint to_i) {
   133   PointsToNode *f = ptnode_adr(from_i);
   134   PointsToNode *t = ptnode_adr(to_i);
   136   assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
   137   assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of Deferred edge");
   138   assert(t->node_type() == PointsToNode::LocalVar || t->node_type() == PointsToNode::Field, "invalid destination of Deferred edge");
   139   // don't add a self-referential edge, this can occur during removal of
   140   // deferred edges
   141   if (from_i != to_i)
   142     add_edge(f, to_i, PointsToNode::DeferredEdge);
   143 }
   145 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
   146   const Type *adr_type = phase->type(adr);
   147   if (adr->is_AddP() && adr_type->isa_oopptr() == NULL &&
   148       adr->in(AddPNode::Address)->is_Proj() &&
   149       adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
   150     // We are computing a raw address for a store captured by an Initialize
   151     // compute an appropriate address type. AddP cases #3 and #5 (see below).
   152     int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
   153     assert(offs != Type::OffsetBot ||
   154            adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
   155            "offset must be a constant or it is initialization of array");
   156     return offs;
   157   }
   158   const TypePtr *t_ptr = adr_type->isa_ptr();
   159   assert(t_ptr != NULL, "must be a pointer type");
   160   return t_ptr->offset();
   161 }
   163 void ConnectionGraph::add_field_edge(uint from_i, uint to_i, int offset) {
   164   PointsToNode *f = ptnode_adr(from_i);
   165   PointsToNode *t = ptnode_adr(to_i);
   167   assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
   168   assert(f->node_type() == PointsToNode::JavaObject, "invalid destination of Field edge");
   169   assert(t->node_type() == PointsToNode::Field, "invalid destination of Field edge");
   170   assert (t->offset() == -1 || t->offset() == offset, "conflicting field offsets");
   171   t->set_offset(offset);
   173   add_edge(f, to_i, PointsToNode::FieldEdge);
   174 }
   176 void ConnectionGraph::set_escape_state(uint ni, PointsToNode::EscapeState es) {
   177   PointsToNode *npt = ptnode_adr(ni);
   178   PointsToNode::EscapeState old_es = npt->escape_state();
   179   if (es > old_es)
   180     npt->set_escape_state(es);
   181 }
   183 void ConnectionGraph::add_node(Node *n, PointsToNode::NodeType nt,
   184                                PointsToNode::EscapeState es, bool done) {
   185   PointsToNode* ptadr = ptnode_adr(n->_idx);
   186   ptadr->_node = n;
   187   ptadr->set_node_type(nt);
   189   // inline set_escape_state(idx, es);
   190   PointsToNode::EscapeState old_es = ptadr->escape_state();
   191   if (es > old_es)
   192     ptadr->set_escape_state(es);
   194   if (done)
   195     _processed.set(n->_idx);
   196 }
   198 PointsToNode::EscapeState ConnectionGraph::escape_state(Node *n) {
   199   uint idx = n->_idx;
   200   PointsToNode::EscapeState es;
   202   // If we are still collecting or there were no non-escaping allocations
   203   // we don't know the answer yet
   204   if (_collecting)
   205     return PointsToNode::UnknownEscape;
   207   // if the node was created after the escape computation, return
   208   // UnknownEscape
   209   if (idx >= nodes_size())
   210     return PointsToNode::UnknownEscape;
   212   es = ptnode_adr(idx)->escape_state();
   214   // if we have already computed a value, return it
   215   if (es != PointsToNode::UnknownEscape &&
   216       ptnode_adr(idx)->node_type() == PointsToNode::JavaObject)
   217     return es;
   219   // PointsTo() calls n->uncast() which can return a new ideal node.
   220   if (n->uncast()->_idx >= nodes_size())
   221     return PointsToNode::UnknownEscape;
   223   PointsToNode::EscapeState orig_es = es;
   225   // compute max escape state of anything this node could point to
   226   for(VectorSetI i(PointsTo(n)); i.test() && es != PointsToNode::GlobalEscape; ++i) {
   227     uint pt = i.elem;
   228     PointsToNode::EscapeState pes = ptnode_adr(pt)->escape_state();
   229     if (pes > es)
   230       es = pes;
   231   }
   232   if (orig_es != es) {
   233     // cache the computed escape state
   234     assert(es != PointsToNode::UnknownEscape, "should have computed an escape state");
   235     ptnode_adr(idx)->set_escape_state(es);
   236   } // orig_es could be PointsToNode::UnknownEscape
   237   return es;
   238 }
   240 VectorSet* ConnectionGraph::PointsTo(Node * n) {
   241   pt_ptset.Reset();
   242   pt_visited.Reset();
   243   pt_worklist.clear();
   245 #ifdef ASSERT
   246   Node *orig_n = n;
   247 #endif
   249   n = n->uncast();
   250   PointsToNode* npt = ptnode_adr(n->_idx);
   252   // If we have a JavaObject, return just that object
   253   if (npt->node_type() == PointsToNode::JavaObject) {
   254     pt_ptset.set(n->_idx);
   255     return &pt_ptset;
   256   }
   257 #ifdef ASSERT
   258   if (npt->_node == NULL) {
   259     if (orig_n != n)
   260       orig_n->dump();
   261     n->dump();
   262     assert(npt->_node != NULL, "unregistered node");
   263   }
   264 #endif
   265   pt_worklist.push(n->_idx);
   266   while(pt_worklist.length() > 0) {
   267     int ni = pt_worklist.pop();
   268     if (pt_visited.test_set(ni))
   269       continue;
   271     PointsToNode* pn = ptnode_adr(ni);
   272     // ensure that all inputs of a Phi have been processed
   273     assert(!_collecting || !pn->_node->is_Phi() || _processed.test(ni),"");
   275     int edges_processed = 0;
   276     uint e_cnt = pn->edge_count();
   277     for (uint e = 0; e < e_cnt; e++) {
   278       uint etgt = pn->edge_target(e);
   279       PointsToNode::EdgeType et = pn->edge_type(e);
   280       if (et == PointsToNode::PointsToEdge) {
   281         pt_ptset.set(etgt);
   282         edges_processed++;
   283       } else if (et == PointsToNode::DeferredEdge) {
   284         pt_worklist.push(etgt);
   285         edges_processed++;
   286       } else {
   287         assert(false,"neither PointsToEdge or DeferredEdge");
   288       }
   289     }
   290     if (edges_processed == 0) {
   291       // no deferred or pointsto edges found.  Assume the value was set
   292       // outside this method.  Add the phantom object to the pointsto set.
   293       pt_ptset.set(_phantom_object);
   294     }
   295   }
   296   return &pt_ptset;
   297 }
   299 void ConnectionGraph::remove_deferred(uint ni, GrowableArray<uint>* deferred_edges, VectorSet* visited) {
   300   // This method is most expensive during ConnectionGraph construction.
   301   // Reuse vectorSet and an additional growable array for deferred edges.
   302   deferred_edges->clear();
   303   visited->Reset();
   305   visited->set(ni);
   306   PointsToNode *ptn = ptnode_adr(ni);
   308   // Mark current edges as visited and move deferred edges to separate array.
   309   for (uint i = 0; i < ptn->edge_count(); ) {
   310     uint t = ptn->edge_target(i);
   311 #ifdef ASSERT
   312     assert(!visited->test_set(t), "expecting no duplications");
   313 #else
   314     visited->set(t);
   315 #endif
   316     if (ptn->edge_type(i) == PointsToNode::DeferredEdge) {
   317       ptn->remove_edge(t, PointsToNode::DeferredEdge);
   318       deferred_edges->append(t);
   319     } else {
   320       i++;
   321     }
   322   }
   323   for (int next = 0; next < deferred_edges->length(); ++next) {
   324     uint t = deferred_edges->at(next);
   325     PointsToNode *ptt = ptnode_adr(t);
   326     uint e_cnt = ptt->edge_count();
   327     for (uint e = 0; e < e_cnt; e++) {
   328       uint etgt = ptt->edge_target(e);
   329       if (visited->test_set(etgt))
   330         continue;
   332       PointsToNode::EdgeType et = ptt->edge_type(e);
   333       if (et == PointsToNode::PointsToEdge) {
   334         add_pointsto_edge(ni, etgt);
   335         if(etgt == _phantom_object) {
   336           // Special case - field set outside (globally escaping).
   337           ptn->set_escape_state(PointsToNode::GlobalEscape);
   338         }
   339       } else if (et == PointsToNode::DeferredEdge) {
   340         deferred_edges->append(etgt);
   341       } else {
   342         assert(false,"invalid connection graph");
   343       }
   344     }
   345   }
   346 }
   349 //  Add an edge to node given by "to_i" from any field of adr_i whose offset
   350 //  matches "offset"  A deferred edge is added if to_i is a LocalVar, and
   351 //  a pointsto edge is added if it is a JavaObject
   353 void ConnectionGraph::add_edge_from_fields(uint adr_i, uint to_i, int offs) {
   354   PointsToNode* an = ptnode_adr(adr_i);
   355   PointsToNode* to = ptnode_adr(to_i);
   356   bool deferred = (to->node_type() == PointsToNode::LocalVar);
   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 (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
   364       if (deferred)
   365         add_deferred_edge(fi, to_i);
   366       else
   367         add_pointsto_edge(fi, to_i);
   368     }
   369   }
   370 }
   372 // Add a deferred  edge from node given by "from_i" to any field of adr_i
   373 // whose offset matches "offset".
   374 void ConnectionGraph::add_deferred_edge_to_fields(uint from_i, uint adr_i, int offs) {
   375   PointsToNode* an = ptnode_adr(adr_i);
   376   for (uint fe = 0; fe < an->edge_count(); fe++) {
   377     assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
   378     int fi = an->edge_target(fe);
   379     PointsToNode* pf = ptnode_adr(fi);
   380     int po = pf->offset();
   381     if (pf->edge_count() == 0) {
   382       // we have not seen any stores to this field, assume it was set outside this method
   383       add_pointsto_edge(fi, _phantom_object);
   384     }
   385     if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
   386       add_deferred_edge(from_i, fi);
   387     }
   388   }
   389 }
   391 // Helper functions
   393 static Node* get_addp_base(Node *addp) {
   394   assert(addp->is_AddP(), "must be AddP");
   395   //
   396   // AddP cases for Base and Address inputs:
   397   // case #1. Direct object's field reference:
   398   //     Allocate
   399   //       |
   400   //     Proj #5 ( oop result )
   401   //       |
   402   //     CheckCastPP (cast to instance type)
   403   //      | |
   404   //     AddP  ( base == address )
   405   //
   406   // case #2. Indirect object's field reference:
   407   //      Phi
   408   //       |
   409   //     CastPP (cast to instance type)
   410   //      | |
   411   //     AddP  ( base == address )
   412   //
   413   // case #3. Raw object's field reference for Initialize node:
   414   //      Allocate
   415   //        |
   416   //      Proj #5 ( oop result )
   417   //  top   |
   418   //     \  |
   419   //     AddP  ( base == top )
   420   //
   421   // case #4. Array's element reference:
   422   //   {CheckCastPP | CastPP}
   423   //     |  | |
   424   //     |  AddP ( array's element offset )
   425   //     |  |
   426   //     AddP ( array's offset )
   427   //
   428   // case #5. Raw object's field reference for arraycopy stub call:
   429   //          The inline_native_clone() case when the arraycopy stub is called
   430   //          after the allocation before Initialize and CheckCastPP nodes.
   431   //      Allocate
   432   //        |
   433   //      Proj #5 ( oop result )
   434   //       | |
   435   //       AddP  ( base == address )
   436   //
   437   // case #6. Constant Pool, ThreadLocal, CastX2P or
   438   //          Raw object's field reference:
   439   //      {ConP, ThreadLocal, CastX2P, raw Load}
   440   //  top   |
   441   //     \  |
   442   //     AddP  ( base == top )
   443   //
   444   // case #7. Klass's field reference.
   445   //      LoadKlass
   446   //       | |
   447   //       AddP  ( base == address )
   448   //
   449   // case #8. narrow Klass's field reference.
   450   //      LoadNKlass
   451   //       |
   452   //      DecodeN
   453   //       | |
   454   //       AddP  ( base == address )
   455   //
   456   Node *base = addp->in(AddPNode::Base)->uncast();
   457   if (base->is_top()) { // The AddP case #3 and #6.
   458     base = addp->in(AddPNode::Address)->uncast();
   459     while (base->is_AddP()) {
   460       // Case #6 (unsafe access) may have several chained AddP nodes.
   461       assert(base->in(AddPNode::Base)->is_top(), "expected unsafe access address only");
   462       base = base->in(AddPNode::Address)->uncast();
   463     }
   464     assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal ||
   465            base->Opcode() == Op_CastX2P || base->is_DecodeN() ||
   466            (base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) ||
   467            (base->is_Proj() && base->in(0)->is_Allocate()), "sanity");
   468   }
   469   return base;
   470 }
   472 static Node* find_second_addp(Node* addp, Node* n) {
   473   assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
   475   Node* addp2 = addp->raw_out(0);
   476   if (addp->outcnt() == 1 && addp2->is_AddP() &&
   477       addp2->in(AddPNode::Base) == n &&
   478       addp2->in(AddPNode::Address) == addp) {
   480     assert(addp->in(AddPNode::Base) == n, "expecting the same base");
   481     //
   482     // Find array's offset to push it on worklist first and
   483     // as result process an array's element offset first (pushed second)
   484     // to avoid CastPP for the array's offset.
   485     // Otherwise the inserted CastPP (LocalVar) will point to what
   486     // the AddP (Field) points to. Which would be wrong since
   487     // the algorithm expects the CastPP has the same point as
   488     // as AddP's base CheckCastPP (LocalVar).
   489     //
   490     //    ArrayAllocation
   491     //     |
   492     //    CheckCastPP
   493     //     |
   494     //    memProj (from ArrayAllocation CheckCastPP)
   495     //     |  ||
   496     //     |  ||   Int (element index)
   497     //     |  ||    |   ConI (log(element size))
   498     //     |  ||    |   /
   499     //     |  ||   LShift
   500     //     |  ||  /
   501     //     |  AddP (array's element offset)
   502     //     |  |
   503     //     |  | ConI (array's offset: #12(32-bits) or #24(64-bits))
   504     //     | / /
   505     //     AddP (array's offset)
   506     //      |
   507     //     Load/Store (memory operation on array's element)
   508     //
   509     return addp2;
   510   }
   511   return NULL;
   512 }
   514 //
   515 // Adjust the type and inputs of an AddP which computes the
   516 // address of a field of an instance
   517 //
   518 bool ConnectionGraph::split_AddP(Node *addp, Node *base,  PhaseGVN  *igvn) {
   519   const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
   520   assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
   521   const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
   522   if (t == NULL) {
   523     // We are computing a raw address for a store captured by an Initialize
   524     // compute an appropriate address type (cases #3 and #5).
   525     assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
   526     assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
   527     intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
   528     assert(offs != Type::OffsetBot, "offset must be a constant");
   529     t = base_t->add_offset(offs)->is_oopptr();
   530   }
   531   int inst_id =  base_t->instance_id();
   532   assert(!t->is_known_instance() || t->instance_id() == inst_id,
   533                              "old type must be non-instance or match new type");
   535   // The type 't' could be subclass of 'base_t'.
   536   // As result t->offset() could be large then base_t's size and it will
   537   // cause the failure in add_offset() with narrow oops since TypeOopPtr()
   538   // constructor verifies correctness of the offset.
   539   //
   540   // It could happened on subclass's branch (from the type profiling
   541   // inlining) which was not eliminated during parsing since the exactness
   542   // of the allocation type was not propagated to the subclass type check.
   543   //
   544   // Or the type 't' could be not related to 'base_t' at all.
   545   // It could happened when CHA type is different from MDO type on a dead path
   546   // (for example, from instanceof check) which is not collapsed during parsing.
   547   //
   548   // Do nothing for such AddP node and don't process its users since
   549   // this code branch will go away.
   550   //
   551   if (!t->is_known_instance() &&
   552       !base_t->klass()->is_subtype_of(t->klass())) {
   553      return false; // bail out
   554   }
   556   const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
   557   // Do NOT remove the next line: ensure a new alias index is allocated
   558   // for the instance type. Note: C++ will not remove it since the call
   559   // has side effect.
   560   int alias_idx = _compile->get_alias_index(tinst);
   561   igvn->set_type(addp, tinst);
   562   // record the allocation in the node map
   563   assert(ptnode_adr(addp->_idx)->_node != NULL, "should be registered");
   564   set_map(addp->_idx, get_map(base->_idx));
   566   // Set addp's Base and Address to 'base'.
   567   Node *abase = addp->in(AddPNode::Base);
   568   Node *adr   = addp->in(AddPNode::Address);
   569   if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
   570       adr->in(0)->_idx == (uint)inst_id) {
   571     // Skip AddP cases #3 and #5.
   572   } else {
   573     assert(!abase->is_top(), "sanity"); // AddP case #3
   574     if (abase != base) {
   575       igvn->hash_delete(addp);
   576       addp->set_req(AddPNode::Base, base);
   577       if (abase == adr) {
   578         addp->set_req(AddPNode::Address, base);
   579       } else {
   580         // AddP case #4 (adr is array's element offset AddP node)
   581 #ifdef ASSERT
   582         const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
   583         assert(adr->is_AddP() && atype != NULL &&
   584                atype->instance_id() == inst_id, "array's element offset should be processed first");
   585 #endif
   586       }
   587       igvn->hash_insert(addp);
   588     }
   589   }
   590   // Put on IGVN worklist since at least addp's type was changed above.
   591   record_for_optimizer(addp);
   592   return true;
   593 }
   595 //
   596 // Create a new version of orig_phi if necessary. Returns either the newly
   597 // created phi or an existing phi.  Sets create_new to indicate wheter  a new
   598 // phi was created.  Cache the last newly created phi in the node map.
   599 //
   600 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn, bool &new_created) {
   601   Compile *C = _compile;
   602   new_created = false;
   603   int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
   604   // nothing to do if orig_phi is bottom memory or matches alias_idx
   605   if (phi_alias_idx == alias_idx) {
   606     return orig_phi;
   607   }
   608   // Have we recently created a Phi for this alias index?
   609   PhiNode *result = get_map_phi(orig_phi->_idx);
   610   if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
   611     return result;
   612   }
   613   // Previous check may fail when the same wide memory Phi was split into Phis
   614   // for different memory slices. Search all Phis for this region.
   615   if (result != NULL) {
   616     Node* region = orig_phi->in(0);
   617     for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
   618       Node* phi = region->fast_out(i);
   619       if (phi->is_Phi() &&
   620           C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
   621         assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
   622         return phi->as_Phi();
   623       }
   624     }
   625   }
   626   if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) {
   627     if (C->do_escape_analysis() == true && !C->failing()) {
   628       // Retry compilation without escape analysis.
   629       // If this is the first failure, the sentinel string will "stick"
   630       // to the Compile object, and the C2Compiler will see it and retry.
   631       C->record_failure(C2Compiler::retry_no_escape_analysis());
   632     }
   633     return NULL;
   634   }
   635   orig_phi_worklist.append_if_missing(orig_phi);
   636   const TypePtr *atype = C->get_adr_type(alias_idx);
   637   result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
   638   C->copy_node_notes_to(result, orig_phi);
   639   igvn->set_type(result, result->bottom_type());
   640   record_for_optimizer(result);
   642   debug_only(Node* pn = ptnode_adr(orig_phi->_idx)->_node;)
   643   assert(pn == NULL || pn == orig_phi, "wrong node");
   644   set_map(orig_phi->_idx, result);
   645   ptnode_adr(orig_phi->_idx)->_node = orig_phi;
   647   new_created = true;
   648   return result;
   649 }
   651 //
   652 // Return a new version  of Memory Phi "orig_phi" with the inputs having the
   653 // specified alias index.
   654 //
   655 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn) {
   657   assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
   658   Compile *C = _compile;
   659   bool new_phi_created;
   660   PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created);
   661   if (!new_phi_created) {
   662     return result;
   663   }
   665   GrowableArray<PhiNode *>  phi_list;
   666   GrowableArray<uint>  cur_input;
   668   PhiNode *phi = orig_phi;
   669   uint idx = 1;
   670   bool finished = false;
   671   while(!finished) {
   672     while (idx < phi->req()) {
   673       Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn);
   674       if (mem != NULL && mem->is_Phi()) {
   675         PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created);
   676         if (new_phi_created) {
   677           // found an phi for which we created a new split, push current one on worklist and begin
   678           // processing new one
   679           phi_list.push(phi);
   680           cur_input.push(idx);
   681           phi = mem->as_Phi();
   682           result = newphi;
   683           idx = 1;
   684           continue;
   685         } else {
   686           mem = newphi;
   687         }
   688       }
   689       if (C->failing()) {
   690         return NULL;
   691       }
   692       result->set_req(idx++, mem);
   693     }
   694 #ifdef ASSERT
   695     // verify that the new Phi has an input for each input of the original
   696     assert( phi->req() == result->req(), "must have same number of inputs.");
   697     assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
   698 #endif
   699     // Check if all new phi's inputs have specified alias index.
   700     // Otherwise use old phi.
   701     for (uint i = 1; i < phi->req(); i++) {
   702       Node* in = result->in(i);
   703       assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
   704     }
   705     // we have finished processing a Phi, see if there are any more to do
   706     finished = (phi_list.length() == 0 );
   707     if (!finished) {
   708       phi = phi_list.pop();
   709       idx = cur_input.pop();
   710       PhiNode *prev_result = get_map_phi(phi->_idx);
   711       prev_result->set_req(idx++, result);
   712       result = prev_result;
   713     }
   714   }
   715   return result;
   716 }
   719 //
   720 // The next methods are derived from methods in MemNode.
   721 //
   722 static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
   723   Node *mem = mmem;
   724   // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
   725   // means an array I have not precisely typed yet.  Do not do any
   726   // alias stuff with it any time soon.
   727   if( toop->base() != Type::AnyPtr &&
   728       !(toop->klass() != NULL &&
   729         toop->klass()->is_java_lang_Object() &&
   730         toop->offset() == Type::OffsetBot) ) {
   731     mem = mmem->memory_at(alias_idx);
   732     // Update input if it is progress over what we have now
   733   }
   734   return mem;
   735 }
   737 //
   738 // Move memory users to their memory slices.
   739 //
   740 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *>  &orig_phis, PhaseGVN *igvn) {
   741   Compile* C = _compile;
   743   const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
   744   assert(tp != NULL, "ptr type");
   745   int alias_idx = C->get_alias_index(tp);
   746   int general_idx = C->get_general_index(alias_idx);
   748   // Move users first
   749   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
   750     Node* use = n->fast_out(i);
   751     if (use->is_MergeMem()) {
   752       MergeMemNode* mmem = use->as_MergeMem();
   753       assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
   754       if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
   755         continue; // Nothing to do
   756       }
   757       // Replace previous general reference to mem node.
   758       uint orig_uniq = C->unique();
   759       Node* m = find_inst_mem(n, general_idx, orig_phis, igvn);
   760       assert(orig_uniq == C->unique(), "no new nodes");
   761       mmem->set_memory_at(general_idx, m);
   762       --imax;
   763       --i;
   764     } else if (use->is_MemBar()) {
   765       assert(!use->is_Initialize(), "initializing stores should not be moved");
   766       if (use->req() > MemBarNode::Precedent &&
   767           use->in(MemBarNode::Precedent) == n) {
   768         // Don't move related membars.
   769         record_for_optimizer(use);
   770         continue;
   771       }
   772       tp = use->as_MemBar()->adr_type()->isa_ptr();
   773       if (tp != NULL && C->get_alias_index(tp) == alias_idx ||
   774           alias_idx == general_idx) {
   775         continue; // Nothing to do
   776       }
   777       // Move to general memory slice.
   778       uint orig_uniq = C->unique();
   779       Node* m = find_inst_mem(n, general_idx, orig_phis, igvn);
   780       assert(orig_uniq == C->unique(), "no new nodes");
   781       igvn->hash_delete(use);
   782       imax -= use->replace_edge(n, m);
   783       igvn->hash_insert(use);
   784       record_for_optimizer(use);
   785       --i;
   786 #ifdef ASSERT
   787     } else if (use->is_Mem()) {
   788       if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) {
   789         // Don't move related cardmark.
   790         continue;
   791       }
   792       // Memory nodes should have new memory input.
   793       tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
   794       assert(tp != NULL, "ptr type");
   795       int idx = C->get_alias_index(tp);
   796       assert(get_map(use->_idx) != NULL || idx == alias_idx,
   797              "Following memory nodes should have new memory input or be on the same memory slice");
   798     } else if (use->is_Phi()) {
   799       // Phi nodes should be split and moved already.
   800       tp = use->as_Phi()->adr_type()->isa_ptr();
   801       assert(tp != NULL, "ptr type");
   802       int idx = C->get_alias_index(tp);
   803       assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
   804     } else {
   805       use->dump();
   806       assert(false, "should not be here");
   807 #endif
   808     }
   809   }
   810 }
   812 //
   813 // Search memory chain of "mem" to find a MemNode whose address
   814 // is the specified alias index.
   815 //
   816 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *>  &orig_phis, PhaseGVN *phase) {
   817   if (orig_mem == NULL)
   818     return orig_mem;
   819   Compile* C = phase->C;
   820   const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
   821   bool is_instance = (toop != NULL) && toop->is_known_instance();
   822   Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
   823   Node *prev = NULL;
   824   Node *result = orig_mem;
   825   while (prev != result) {
   826     prev = result;
   827     if (result == start_mem)
   828       break;  // hit one of our sentinels
   829     if (result->is_Mem()) {
   830       const Type *at = phase->type(result->in(MemNode::Address));
   831       if (at != Type::TOP) {
   832         assert (at->isa_ptr() != NULL, "pointer type required.");
   833         int idx = C->get_alias_index(at->is_ptr());
   834         if (idx == alias_idx)
   835           break;
   836       }
   837       result = result->in(MemNode::Memory);
   838     }
   839     if (!is_instance)
   840       continue;  // don't search further for non-instance types
   841     // skip over a call which does not affect this memory slice
   842     if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
   843       Node *proj_in = result->in(0);
   844       if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
   845         break;  // hit one of our sentinels
   846       } else if (proj_in->is_Call()) {
   847         CallNode *call = proj_in->as_Call();
   848         if (!call->may_modify(toop, phase)) {
   849           result = call->in(TypeFunc::Memory);
   850         }
   851       } else if (proj_in->is_Initialize()) {
   852         AllocateNode* alloc = proj_in->as_Initialize()->allocation();
   853         // Stop if this is the initialization for the object instance which
   854         // which contains this memory slice, otherwise skip over it.
   855         if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) {
   856           result = proj_in->in(TypeFunc::Memory);
   857         }
   858       } else if (proj_in->is_MemBar()) {
   859         result = proj_in->in(TypeFunc::Memory);
   860       }
   861     } else if (result->is_MergeMem()) {
   862       MergeMemNode *mmem = result->as_MergeMem();
   863       result = step_through_mergemem(mmem, alias_idx, toop);
   864       if (result == mmem->base_memory()) {
   865         // Didn't find instance memory, search through general slice recursively.
   866         result = mmem->memory_at(C->get_general_index(alias_idx));
   867         result = find_inst_mem(result, alias_idx, orig_phis, phase);
   868         if (C->failing()) {
   869           return NULL;
   870         }
   871         mmem->set_memory_at(alias_idx, result);
   872       }
   873     } else if (result->is_Phi() &&
   874                C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
   875       Node *un = result->as_Phi()->unique_input(phase);
   876       if (un != NULL) {
   877         orig_phis.append_if_missing(result->as_Phi());
   878         result = un;
   879       } else {
   880         break;
   881       }
   882     } else if (result->is_ClearArray()) {
   883       if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), phase)) {
   884         // Can not bypass initialization of the instance
   885         // we are looking for.
   886         break;
   887       }
   888       // Otherwise skip it (the call updated 'result' value).
   889     } else if (result->Opcode() == Op_SCMemProj) {
   890       assert(result->in(0)->is_LoadStore(), "sanity");
   891       const Type *at = phase->type(result->in(0)->in(MemNode::Address));
   892       if (at != Type::TOP) {
   893         assert (at->isa_ptr() != NULL, "pointer type required.");
   894         int idx = C->get_alias_index(at->is_ptr());
   895         assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field");
   896         break;
   897       }
   898       result = result->in(0)->in(MemNode::Memory);
   899     }
   900   }
   901   if (result->is_Phi()) {
   902     PhiNode *mphi = result->as_Phi();
   903     assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
   904     const TypePtr *t = mphi->adr_type();
   905     if (C->get_alias_index(t) != alias_idx) {
   906       // Create a new Phi with the specified alias index type.
   907       result = split_memory_phi(mphi, alias_idx, orig_phis, phase);
   908     } else if (!is_instance) {
   909       // Push all non-instance Phis on the orig_phis worklist to update inputs
   910       // during Phase 4 if needed.
   911       orig_phis.append_if_missing(mphi);
   912     }
   913   }
   914   // the result is either MemNode, PhiNode, InitializeNode.
   915   return result;
   916 }
   918 //
   919 //  Convert the types of unescaped object to instance types where possible,
   920 //  propagate the new type information through the graph, and update memory
   921 //  edges and MergeMem inputs to reflect the new type.
   922 //
   923 //  We start with allocations (and calls which may be allocations)  on alloc_worklist.
   924 //  The processing is done in 4 phases:
   925 //
   926 //  Phase 1:  Process possible allocations from alloc_worklist.  Create instance
   927 //            types for the CheckCastPP for allocations where possible.
   928 //            Propagate the the new types through users as follows:
   929 //               casts and Phi:  push users on alloc_worklist
   930 //               AddP:  cast Base and Address inputs to the instance type
   931 //                      push any AddP users on alloc_worklist and push any memnode
   932 //                      users onto memnode_worklist.
   933 //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
   934 //            search the Memory chain for a store with the appropriate type
   935 //            address type.  If a Phi is found, create a new version with
   936 //            the appropriate memory slices from each of the Phi inputs.
   937 //            For stores, process the users as follows:
   938 //               MemNode:  push on memnode_worklist
   939 //               MergeMem: push on mergemem_worklist
   940 //  Phase 3:  Process MergeMem nodes from mergemem_worklist.  Walk each memory slice
   941 //            moving the first node encountered of each  instance type to the
   942 //            the input corresponding to its alias index.
   943 //            appropriate memory slice.
   944 //  Phase 4:  Update the inputs of non-instance memory Phis and the Memory input of memnodes.
   945 //
   946 // In the following example, the CheckCastPP nodes are the cast of allocation
   947 // results and the allocation of node 29 is unescaped and eligible to be an
   948 // instance type.
   949 //
   950 // We start with:
   951 //
   952 //     7 Parm #memory
   953 //    10  ConI  "12"
   954 //    19  CheckCastPP   "Foo"
   955 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   956 //    29  CheckCastPP   "Foo"
   957 //    30  AddP  _ 29 29 10  Foo+12  alias_index=4
   958 //
   959 //    40  StoreP  25   7  20   ... alias_index=4
   960 //    50  StoreP  35  40  30   ... alias_index=4
   961 //    60  StoreP  45  50  20   ... alias_index=4
   962 //    70  LoadP    _  60  30   ... alias_index=4
   963 //    80  Phi     75  50  60   Memory alias_index=4
   964 //    90  LoadP    _  80  30   ... alias_index=4
   965 //   100  LoadP    _  80  20   ... alias_index=4
   966 //
   967 //
   968 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
   969 // and creating a new alias index for node 30.  This gives:
   970 //
   971 //     7 Parm #memory
   972 //    10  ConI  "12"
   973 //    19  CheckCastPP   "Foo"
   974 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   975 //    29  CheckCastPP   "Foo"  iid=24
   976 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
   977 //
   978 //    40  StoreP  25   7  20   ... alias_index=4
   979 //    50  StoreP  35  40  30   ... alias_index=6
   980 //    60  StoreP  45  50  20   ... alias_index=4
   981 //    70  LoadP    _  60  30   ... alias_index=6
   982 //    80  Phi     75  50  60   Memory alias_index=4
   983 //    90  LoadP    _  80  30   ... alias_index=6
   984 //   100  LoadP    _  80  20   ... alias_index=4
   985 //
   986 // In phase 2, new memory inputs are computed for the loads and stores,
   987 // And a new version of the phi is created.  In phase 4, the inputs to
   988 // node 80 are updated and then the memory nodes are updated with the
   989 // values computed in phase 2.  This results in:
   990 //
   991 //     7 Parm #memory
   992 //    10  ConI  "12"
   993 //    19  CheckCastPP   "Foo"
   994 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
   995 //    29  CheckCastPP   "Foo"  iid=24
   996 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
   997 //
   998 //    40  StoreP  25  7   20   ... alias_index=4
   999 //    50  StoreP  35  7   30   ... alias_index=6
  1000 //    60  StoreP  45  40  20   ... alias_index=4
  1001 //    70  LoadP    _  50  30   ... alias_index=6
  1002 //    80  Phi     75  40  60   Memory alias_index=4
  1003 //   120  Phi     75  50  50   Memory alias_index=6
  1004 //    90  LoadP    _ 120  30   ... alias_index=6
  1005 //   100  LoadP    _  80  20   ... alias_index=4
  1006 //
  1007 void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist) {
  1008   GrowableArray<Node *>  memnode_worklist;
  1009   GrowableArray<PhiNode *>  orig_phis;
  1011   PhaseIterGVN  *igvn = _igvn;
  1012   uint new_index_start = (uint) _compile->num_alias_types();
  1013   Arena* arena = Thread::current()->resource_area();
  1014   VectorSet visited(arena);
  1017   //  Phase 1:  Process possible allocations from alloc_worklist.
  1018   //  Create instance types for the CheckCastPP for allocations where possible.
  1019   //
  1020   // (Note: don't forget to change the order of the second AddP node on
  1021   //  the alloc_worklist if the order of the worklist processing is changed,
  1022   //  see the comment in find_second_addp().)
  1023   //
  1024   while (alloc_worklist.length() != 0) {
  1025     Node *n = alloc_worklist.pop();
  1026     uint ni = n->_idx;
  1027     const TypeOopPtr* tinst = NULL;
  1028     if (n->is_Call()) {
  1029       CallNode *alloc = n->as_Call();
  1030       // copy escape information to call node
  1031       PointsToNode* ptn = ptnode_adr(alloc->_idx);
  1032       PointsToNode::EscapeState es = escape_state(alloc);
  1033       // We have an allocation or call which returns a Java object,
  1034       // see if it is unescaped.
  1035       if (es != PointsToNode::NoEscape || !ptn->_scalar_replaceable)
  1036         continue;
  1038       // Find CheckCastPP for the allocate or for the return value of a call
  1039       n = alloc->result_cast();
  1040       if (n == NULL) {            // No uses except Initialize node
  1041         if (alloc->is_Allocate()) {
  1042           // Set the scalar_replaceable flag for allocation
  1043           // so it could be eliminated if it has no uses.
  1044           alloc->as_Allocate()->_is_scalar_replaceable = true;
  1046         continue;
  1048       if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
  1049         assert(!alloc->is_Allocate(), "allocation should have unique type");
  1050         continue;
  1053       // The inline code for Object.clone() casts the allocation result to
  1054       // java.lang.Object and then to the actual type of the allocated
  1055       // object. Detect this case and use the second cast.
  1056       // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
  1057       // the allocation result is cast to java.lang.Object and then
  1058       // to the actual Array type.
  1059       if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
  1060           && (alloc->is_AllocateArray() ||
  1061               igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
  1062         Node *cast2 = NULL;
  1063         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1064           Node *use = n->fast_out(i);
  1065           if (use->is_CheckCastPP()) {
  1066             cast2 = use;
  1067             break;
  1070         if (cast2 != NULL) {
  1071           n = cast2;
  1072         } else {
  1073           // Non-scalar replaceable if the allocation type is unknown statically
  1074           // (reflection allocation), the object can't be restored during
  1075           // deoptimization without precise type.
  1076           continue;
  1079       if (alloc->is_Allocate()) {
  1080         // Set the scalar_replaceable flag for allocation
  1081         // so it could be eliminated.
  1082         alloc->as_Allocate()->_is_scalar_replaceable = true;
  1084       set_escape_state(n->_idx, es);
  1085       // in order for an object to be scalar-replaceable, it must be:
  1086       //   - a direct allocation (not a call returning an object)
  1087       //   - non-escaping
  1088       //   - eligible to be a unique type
  1089       //   - not determined to be ineligible by escape analysis
  1090       assert(ptnode_adr(alloc->_idx)->_node != NULL &&
  1091              ptnode_adr(n->_idx)->_node != NULL, "should be registered");
  1092       set_map(alloc->_idx, n);
  1093       set_map(n->_idx, alloc);
  1094       const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
  1095       if (t == NULL)
  1096         continue;  // not a TypeInstPtr
  1097       tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni);
  1098       igvn->hash_delete(n);
  1099       igvn->set_type(n,  tinst);
  1100       n->raise_bottom_type(tinst);
  1101       igvn->hash_insert(n);
  1102       record_for_optimizer(n);
  1103       if (alloc->is_Allocate() && ptn->_scalar_replaceable &&
  1104           (t->isa_instptr() || t->isa_aryptr())) {
  1106         // First, put on the worklist all Field edges from Connection Graph
  1107         // which is more accurate then putting immediate users from Ideal Graph.
  1108         for (uint e = 0; e < ptn->edge_count(); e++) {
  1109           Node *use = ptnode_adr(ptn->edge_target(e))->_node;
  1110           assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(),
  1111                  "only AddP nodes are Field edges in CG");
  1112           if (use->outcnt() > 0) { // Don't process dead nodes
  1113             Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
  1114             if (addp2 != NULL) {
  1115               assert(alloc->is_AllocateArray(),"array allocation was expected");
  1116               alloc_worklist.append_if_missing(addp2);
  1118             alloc_worklist.append_if_missing(use);
  1122         // An allocation may have an Initialize which has raw stores. Scan
  1123         // the users of the raw allocation result and push AddP users
  1124         // on alloc_worklist.
  1125         Node *raw_result = alloc->proj_out(TypeFunc::Parms);
  1126         assert (raw_result != NULL, "must have an allocation result");
  1127         for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
  1128           Node *use = raw_result->fast_out(i);
  1129           if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
  1130             Node* addp2 = find_second_addp(use, raw_result);
  1131             if (addp2 != NULL) {
  1132               assert(alloc->is_AllocateArray(),"array allocation was expected");
  1133               alloc_worklist.append_if_missing(addp2);
  1135             alloc_worklist.append_if_missing(use);
  1136           } else if (use->is_MemBar()) {
  1137             memnode_worklist.append_if_missing(use);
  1141     } else if (n->is_AddP()) {
  1142       VectorSet* ptset = PointsTo(get_addp_base(n));
  1143       assert(ptset->Size() == 1, "AddP address is unique");
  1144       uint elem = ptset->getelem(); // Allocation node's index
  1145       if (elem == _phantom_object) {
  1146         assert(false, "escaped allocation");
  1147         continue; // Assume the value was set outside this method.
  1149       Node *base = get_map(elem);  // CheckCastPP node
  1150       if (!split_AddP(n, base, igvn)) continue; // wrong type from dead path
  1151       tinst = igvn->type(base)->isa_oopptr();
  1152     } else if (n->is_Phi() ||
  1153                n->is_CheckCastPP() ||
  1154                n->is_EncodeP() ||
  1155                n->is_DecodeN() ||
  1156                (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
  1157       if (visited.test_set(n->_idx)) {
  1158         assert(n->is_Phi(), "loops only through Phi's");
  1159         continue;  // already processed
  1161       VectorSet* ptset = PointsTo(n);
  1162       if (ptset->Size() == 1) {
  1163         uint elem = ptset->getelem(); // Allocation node's index
  1164         if (elem == _phantom_object) {
  1165           assert(false, "escaped allocation");
  1166           continue; // Assume the value was set outside this method.
  1168         Node *val = get_map(elem);   // CheckCastPP node
  1169         TypeNode *tn = n->as_Type();
  1170         tinst = igvn->type(val)->isa_oopptr();
  1171         assert(tinst != NULL && tinst->is_known_instance() &&
  1172                (uint)tinst->instance_id() == elem , "instance type expected.");
  1174         const Type *tn_type = igvn->type(tn);
  1175         const TypeOopPtr *tn_t;
  1176         if (tn_type->isa_narrowoop()) {
  1177           tn_t = tn_type->make_ptr()->isa_oopptr();
  1178         } else {
  1179           tn_t = tn_type->isa_oopptr();
  1182         if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) {
  1183           if (tn_type->isa_narrowoop()) {
  1184             tn_type = tinst->make_narrowoop();
  1185           } else {
  1186             tn_type = tinst;
  1188           igvn->hash_delete(tn);
  1189           igvn->set_type(tn, tn_type);
  1190           tn->set_type(tn_type);
  1191           igvn->hash_insert(tn);
  1192           record_for_optimizer(n);
  1193         } else {
  1194           assert(tn_type == TypePtr::NULL_PTR ||
  1195                  tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()),
  1196                  "unexpected type");
  1197           continue; // Skip dead path with different type
  1200     } else {
  1201       debug_only(n->dump();)
  1202       assert(false, "EA: unexpected node");
  1203       continue;
  1205     // push allocation's users on appropriate worklist
  1206     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1207       Node *use = n->fast_out(i);
  1208       if(use->is_Mem() && use->in(MemNode::Address) == n) {
  1209         // Load/store to instance's field
  1210         memnode_worklist.append_if_missing(use);
  1211       } else if (use->is_MemBar()) {
  1212         memnode_worklist.append_if_missing(use);
  1213       } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
  1214         Node* addp2 = find_second_addp(use, n);
  1215         if (addp2 != NULL) {
  1216           alloc_worklist.append_if_missing(addp2);
  1218         alloc_worklist.append_if_missing(use);
  1219       } else if (use->is_Phi() ||
  1220                  use->is_CheckCastPP() ||
  1221                  use->is_EncodeP() ||
  1222                  use->is_DecodeN() ||
  1223                  (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
  1224         alloc_worklist.append_if_missing(use);
  1225 #ifdef ASSERT
  1226       } else if (use->is_Mem()) {
  1227         assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
  1228       } else if (use->is_MergeMem()) {
  1229         assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
  1230       } else if (use->is_SafePoint()) {
  1231         // Look for MergeMem nodes for calls which reference unique allocation
  1232         // (through CheckCastPP nodes) even for debug info.
  1233         Node* m = use->in(TypeFunc::Memory);
  1234         if (m->is_MergeMem()) {
  1235           assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
  1237       } else {
  1238         uint op = use->Opcode();
  1239         if (!(op == Op_CmpP || op == Op_Conv2B ||
  1240               op == Op_CastP2X || op == Op_StoreCM ||
  1241               op == Op_FastLock || op == Op_AryEq || op == Op_StrComp ||
  1242               op == Op_StrEquals || op == Op_StrIndexOf)) {
  1243           n->dump();
  1244           use->dump();
  1245           assert(false, "EA: missing allocation reference path");
  1247 #endif
  1252   // New alias types were created in split_AddP().
  1253   uint new_index_end = (uint) _compile->num_alias_types();
  1255   //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
  1256   //            compute new values for Memory inputs  (the Memory inputs are not
  1257   //            actually updated until phase 4.)
  1258   if (memnode_worklist.length() == 0)
  1259     return;  // nothing to do
  1261   while (memnode_worklist.length() != 0) {
  1262     Node *n = memnode_worklist.pop();
  1263     if (visited.test_set(n->_idx))
  1264       continue;
  1265     if (n->is_Phi() || n->is_ClearArray()) {
  1266       // we don't need to do anything, but the users must be pushed
  1267     } else if (n->is_MemBar()) { // Initialize, MemBar nodes
  1268       // we don't need to do anything, but the users must be pushed
  1269       n = n->as_MemBar()->proj_out(TypeFunc::Memory);
  1270       if (n == NULL)
  1271         continue;
  1272     } else {
  1273       assert(n->is_Mem(), "memory node required.");
  1274       Node *addr = n->in(MemNode::Address);
  1275       const Type *addr_t = igvn->type(addr);
  1276       if (addr_t == Type::TOP)
  1277         continue;
  1278       assert (addr_t->isa_ptr() != NULL, "pointer type required.");
  1279       int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
  1280       assert ((uint)alias_idx < new_index_end, "wrong alias index");
  1281       Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn);
  1282       if (_compile->failing()) {
  1283         return;
  1285       if (mem != n->in(MemNode::Memory)) {
  1286         // We delay the memory edge update since we need old one in
  1287         // MergeMem code below when instances memory slices are separated.
  1288         debug_only(Node* pn = ptnode_adr(n->_idx)->_node;)
  1289         assert(pn == NULL || pn == n, "wrong node");
  1290         set_map(n->_idx, mem);
  1291         ptnode_adr(n->_idx)->_node = n;
  1293       if (n->is_Load()) {
  1294         continue;  // don't push users
  1295       } else if (n->is_LoadStore()) {
  1296         // get the memory projection
  1297         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1298           Node *use = n->fast_out(i);
  1299           if (use->Opcode() == Op_SCMemProj) {
  1300             n = use;
  1301             break;
  1304         assert(n->Opcode() == Op_SCMemProj, "memory projection required");
  1307     // push user on appropriate worklist
  1308     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1309       Node *use = n->fast_out(i);
  1310       if (use->is_Phi() || use->is_ClearArray()) {
  1311         memnode_worklist.append_if_missing(use);
  1312       } else if(use->is_Mem() && use->in(MemNode::Memory) == n) {
  1313         if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores
  1314           continue;
  1315         memnode_worklist.append_if_missing(use);
  1316       } else if (use->is_MemBar()) {
  1317         memnode_worklist.append_if_missing(use);
  1318 #ifdef ASSERT
  1319       } else if(use->is_Mem()) {
  1320         assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
  1321       } else if (use->is_MergeMem()) {
  1322         assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
  1323       } else {
  1324         uint op = use->Opcode();
  1325         if (!(op == Op_StoreCM ||
  1326               (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL &&
  1327                strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) ||
  1328               op == Op_AryEq || op == Op_StrComp ||
  1329               op == Op_StrEquals || op == Op_StrIndexOf)) {
  1330           n->dump();
  1331           use->dump();
  1332           assert(false, "EA: missing memory path");
  1334 #endif
  1339   //  Phase 3:  Process MergeMem nodes from mergemem_worklist.
  1340   //            Walk each memory slice moving the first node encountered of each
  1341   //            instance type to the the input corresponding to its alias index.
  1342   uint length = _mergemem_worklist.length();
  1343   for( uint next = 0; next < length; ++next ) {
  1344     MergeMemNode* nmm = _mergemem_worklist.at(next);
  1345     assert(!visited.test_set(nmm->_idx), "should not be visited before");
  1346     // Note: we don't want to use MergeMemStream here because we only want to
  1347     // scan inputs which exist at the start, not ones we add during processing.
  1348     // Note 2: MergeMem may already contains instance memory slices added
  1349     // during find_inst_mem() call when memory nodes were processed above.
  1350     igvn->hash_delete(nmm);
  1351     uint nslices = nmm->req();
  1352     for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
  1353       Node* mem = nmm->in(i);
  1354       Node* cur = NULL;
  1355       if (mem == NULL || mem->is_top())
  1356         continue;
  1357       // First, update mergemem by moving memory nodes to corresponding slices
  1358       // if their type became more precise since this mergemem was created.
  1359       while (mem->is_Mem()) {
  1360         const Type *at = igvn->type(mem->in(MemNode::Address));
  1361         if (at != Type::TOP) {
  1362           assert (at->isa_ptr() != NULL, "pointer type required.");
  1363           uint idx = (uint)_compile->get_alias_index(at->is_ptr());
  1364           if (idx == i) {
  1365             if (cur == NULL)
  1366               cur = mem;
  1367           } else {
  1368             if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
  1369               nmm->set_memory_at(idx, mem);
  1373         mem = mem->in(MemNode::Memory);
  1375       nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
  1376       // Find any instance of the current type if we haven't encountered
  1377       // already a memory slice of the instance along the memory chain.
  1378       for (uint ni = new_index_start; ni < new_index_end; ni++) {
  1379         if((uint)_compile->get_general_index(ni) == i) {
  1380           Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
  1381           if (nmm->is_empty_memory(m)) {
  1382             Node* result = find_inst_mem(mem, ni, orig_phis, igvn);
  1383             if (_compile->failing()) {
  1384               return;
  1386             nmm->set_memory_at(ni, result);
  1391     // Find the rest of instances values
  1392     for (uint ni = new_index_start; ni < new_index_end; ni++) {
  1393       const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
  1394       Node* result = step_through_mergemem(nmm, ni, tinst);
  1395       if (result == nmm->base_memory()) {
  1396         // Didn't find instance memory, search through general slice recursively.
  1397         result = nmm->memory_at(_compile->get_general_index(ni));
  1398         result = find_inst_mem(result, ni, orig_phis, igvn);
  1399         if (_compile->failing()) {
  1400           return;
  1402         nmm->set_memory_at(ni, result);
  1405     igvn->hash_insert(nmm);
  1406     record_for_optimizer(nmm);
  1409   //  Phase 4:  Update the inputs of non-instance memory Phis and
  1410   //            the Memory input of memnodes
  1411   // First update the inputs of any non-instance Phi's from
  1412   // which we split out an instance Phi.  Note we don't have
  1413   // to recursively process Phi's encounted on the input memory
  1414   // chains as is done in split_memory_phi() since they  will
  1415   // also be processed here.
  1416   for (int j = 0; j < orig_phis.length(); j++) {
  1417     PhiNode *phi = orig_phis.at(j);
  1418     int alias_idx = _compile->get_alias_index(phi->adr_type());
  1419     igvn->hash_delete(phi);
  1420     for (uint i = 1; i < phi->req(); i++) {
  1421       Node *mem = phi->in(i);
  1422       Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn);
  1423       if (_compile->failing()) {
  1424         return;
  1426       if (mem != new_mem) {
  1427         phi->set_req(i, new_mem);
  1430     igvn->hash_insert(phi);
  1431     record_for_optimizer(phi);
  1434   // Update the memory inputs of MemNodes with the value we computed
  1435   // in Phase 2 and move stores memory users to corresponding memory slices.
  1436 #ifdef ASSERT
  1437   visited.Reset();
  1438   Node_Stack old_mems(arena, _compile->unique() >> 2);
  1439 #endif
  1440   for (uint i = 0; i < nodes_size(); i++) {
  1441     Node *nmem = get_map(i);
  1442     if (nmem != NULL) {
  1443       Node *n = ptnode_adr(i)->_node;
  1444       assert(n != NULL, "sanity");
  1445       if (n->is_Mem()) {
  1446 #ifdef ASSERT
  1447         Node* old_mem = n->in(MemNode::Memory);
  1448         if (!visited.test_set(old_mem->_idx)) {
  1449           old_mems.push(old_mem, old_mem->outcnt());
  1451 #endif
  1452         assert(n->in(MemNode::Memory) != nmem, "sanity");
  1453         if (!n->is_Load()) {
  1454           // Move memory users of a store first.
  1455           move_inst_mem(n, orig_phis, igvn);
  1457         // Now update memory input
  1458         igvn->hash_delete(n);
  1459         n->set_req(MemNode::Memory, nmem);
  1460         igvn->hash_insert(n);
  1461         record_for_optimizer(n);
  1462       } else {
  1463         assert(n->is_Allocate() || n->is_CheckCastPP() ||
  1464                n->is_AddP() || n->is_Phi(), "unknown node used for set_map()");
  1468 #ifdef ASSERT
  1469   // Verify that memory was split correctly
  1470   while (old_mems.is_nonempty()) {
  1471     Node* old_mem = old_mems.node();
  1472     uint  old_cnt = old_mems.index();
  1473     old_mems.pop();
  1474     assert(old_cnt = old_mem->outcnt(), "old mem could be lost");
  1476 #endif
  1479 bool ConnectionGraph::has_candidates(Compile *C) {
  1480   // EA brings benefits only when the code has allocations and/or locks which
  1481   // are represented by ideal Macro nodes.
  1482   int cnt = C->macro_count();
  1483   for( int i=0; i < cnt; i++ ) {
  1484     Node *n = C->macro_node(i);
  1485     if ( n->is_Allocate() )
  1486       return true;
  1487     if( n->is_Lock() ) {
  1488       Node* obj = n->as_Lock()->obj_node()->uncast();
  1489       if( !(obj->is_Parm() || obj->is_Con()) )
  1490         return true;
  1493   return false;
  1496 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
  1497   // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction
  1498   // to create space for them in ConnectionGraph::_nodes[].
  1499   Node* oop_null = igvn->zerocon(T_OBJECT);
  1500   Node* noop_null = igvn->zerocon(T_NARROWOOP);
  1502   ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn);
  1503   // Perform escape analysis
  1504   if (congraph->compute_escape()) {
  1505     // There are non escaping objects.
  1506     C->set_congraph(congraph);
  1509   // Cleanup.
  1510   if (oop_null->outcnt() == 0)
  1511     igvn->hash_delete(oop_null);
  1512   if (noop_null->outcnt() == 0)
  1513     igvn->hash_delete(noop_null);
  1516 bool ConnectionGraph::compute_escape() {
  1517   Compile* C = _compile;
  1519   // 1. Populate Connection Graph (CG) with Ideal nodes.
  1521   Unique_Node_List worklist_init;
  1522   worklist_init.map(C->unique(), NULL);  // preallocate space
  1524   // Initialize worklist
  1525   if (C->root() != NULL) {
  1526     worklist_init.push(C->root());
  1529   GrowableArray<int> cg_worklist;
  1530   PhaseGVN* igvn = _igvn;
  1531   bool has_allocations = false;
  1533   // Push all useful nodes onto CG list and set their type.
  1534   for( uint next = 0; next < worklist_init.size(); ++next ) {
  1535     Node* n = worklist_init.at(next);
  1536     record_for_escape_analysis(n, igvn);
  1537     // Only allocations and java static calls results are checked
  1538     // for an escape status. See process_call_result() below.
  1539     if (n->is_Allocate() || n->is_CallStaticJava() &&
  1540         ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) {
  1541       has_allocations = true;
  1543     if(n->is_AddP()) {
  1544       // Collect address nodes. Use them during stage 3 below
  1545       // to build initial connection graph field edges.
  1546       cg_worklist.append(n->_idx);
  1547     } else if (n->is_MergeMem()) {
  1548       // Collect all MergeMem nodes to add memory slices for
  1549       // scalar replaceable objects in split_unique_types().
  1550       _mergemem_worklist.append(n->as_MergeMem());
  1552     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1553       Node* m = n->fast_out(i);   // Get user
  1554       worklist_init.push(m);
  1558   if (!has_allocations) {
  1559     _collecting = false;
  1560     return false; // Nothing to do.
  1563   // 2. First pass to create simple CG edges (doesn't require to walk CG).
  1564   uint delayed_size = _delayed_worklist.size();
  1565   for( uint next = 0; next < delayed_size; ++next ) {
  1566     Node* n = _delayed_worklist.at(next);
  1567     build_connection_graph(n, igvn);
  1570   // 3. Pass to create initial fields edges (JavaObject -F-> AddP)
  1571   //    to reduce number of iterations during stage 4 below.
  1572   uint cg_length = cg_worklist.length();
  1573   for( uint next = 0; next < cg_length; ++next ) {
  1574     int ni = cg_worklist.at(next);
  1575     Node* n = ptnode_adr(ni)->_node;
  1576     Node* base = get_addp_base(n);
  1577     if (base->is_Proj())
  1578       base = base->in(0);
  1579     PointsToNode::NodeType nt = ptnode_adr(base->_idx)->node_type();
  1580     if (nt == PointsToNode::JavaObject) {
  1581       build_connection_graph(n, igvn);
  1585   cg_worklist.clear();
  1586   cg_worklist.append(_phantom_object);
  1587   GrowableArray<uint>  worklist;
  1589   // 4. Build Connection Graph which need
  1590   //    to walk the connection graph.
  1591   _progress = false;
  1592   for (uint ni = 0; ni < nodes_size(); ni++) {
  1593     PointsToNode* ptn = ptnode_adr(ni);
  1594     Node *n = ptn->_node;
  1595     if (n != NULL) { // Call, AddP, LoadP, StoreP
  1596       build_connection_graph(n, igvn);
  1597       if (ptn->node_type() != PointsToNode::UnknownType)
  1598         cg_worklist.append(n->_idx); // Collect CG nodes
  1599       if (!_processed.test(n->_idx))
  1600         worklist.append(n->_idx); // Collect C/A/L/S nodes
  1604   // After IGVN user nodes may have smaller _idx than
  1605   // their inputs so they will be processed first in
  1606   // previous loop. Because of that not all Graph
  1607   // edges will be created. Walk over interesting
  1608   // nodes again until no new edges are created.
  1609   //
  1610   // Normally only 1-3 passes needed to build
  1611   // Connection Graph depending on graph complexity.
  1612   // Observed 8 passes in jvm2008 compiler.compiler.
  1613   // Set limit to 20 to catch situation when something
  1614   // did go wrong and recompile the method without EA.
  1616 #define CG_BUILD_ITER_LIMIT 20
  1618   uint length = worklist.length();
  1619   int iterations = 0;
  1620   while(_progress && (iterations++ < CG_BUILD_ITER_LIMIT)) {
  1621     _progress = false;
  1622     for( uint next = 0; next < length; ++next ) {
  1623       int ni = worklist.at(next);
  1624       PointsToNode* ptn = ptnode_adr(ni);
  1625       Node* n = ptn->_node;
  1626       assert(n != NULL, "should be known node");
  1627       build_connection_graph(n, igvn);
  1630   if (iterations >= CG_BUILD_ITER_LIMIT) {
  1631     assert(iterations < CG_BUILD_ITER_LIMIT,
  1632            err_msg("infinite EA connection graph build with %d nodes and worklist size %d",
  1633            nodes_size(), length));
  1634     // Possible infinite build_connection_graph loop,
  1635     // retry compilation without escape analysis.
  1636     C->record_failure(C2Compiler::retry_no_escape_analysis());
  1637     _collecting = false;
  1638     return false;
  1640 #undef CG_BUILD_ITER_LIMIT
  1642   Arena* arena = Thread::current()->resource_area();
  1643   VectorSet visited(arena);
  1644   worklist.clear();
  1646   // 5. Remove deferred edges from the graph and adjust
  1647   //    escape state of nonescaping objects.
  1648   cg_length = cg_worklist.length();
  1649   for( uint next = 0; next < cg_length; ++next ) {
  1650     int ni = cg_worklist.at(next);
  1651     PointsToNode* ptn = ptnode_adr(ni);
  1652     PointsToNode::NodeType nt = ptn->node_type();
  1653     if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) {
  1654       remove_deferred(ni, &worklist, &visited);
  1655       Node *n = ptn->_node;
  1656       if (n->is_AddP()) {
  1657         // Search for objects which are not scalar replaceable
  1658         // and adjust their escape state.
  1659         adjust_escape_state(ni, igvn);
  1664   // 6. Propagate escape states.
  1665   worklist.clear();
  1666   bool has_non_escaping_obj = false;
  1668   // push all GlobalEscape nodes on the worklist
  1669   for( uint next = 0; next < cg_length; ++next ) {
  1670     int nk = cg_worklist.at(next);
  1671     if (ptnode_adr(nk)->escape_state() == PointsToNode::GlobalEscape)
  1672       worklist.push(nk);
  1674   // mark all nodes reachable from GlobalEscape nodes
  1675   while(worklist.length() > 0) {
  1676     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1677     uint e_cnt = ptn->edge_count();
  1678     for (uint ei = 0; ei < e_cnt; ei++) {
  1679       uint npi = ptn->edge_target(ei);
  1680       PointsToNode *np = ptnode_adr(npi);
  1681       if (np->escape_state() < PointsToNode::GlobalEscape) {
  1682         np->set_escape_state(PointsToNode::GlobalEscape);
  1683         worklist.push(npi);
  1688   // push all ArgEscape nodes on the worklist
  1689   for( uint next = 0; next < cg_length; ++next ) {
  1690     int nk = cg_worklist.at(next);
  1691     if (ptnode_adr(nk)->escape_state() == PointsToNode::ArgEscape)
  1692       worklist.push(nk);
  1694   // mark all nodes reachable from ArgEscape nodes
  1695   while(worklist.length() > 0) {
  1696     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1697     if (ptn->node_type() == PointsToNode::JavaObject)
  1698       has_non_escaping_obj = true; // Non GlobalEscape
  1699     uint e_cnt = ptn->edge_count();
  1700     for (uint ei = 0; ei < e_cnt; ei++) {
  1701       uint npi = ptn->edge_target(ei);
  1702       PointsToNode *np = ptnode_adr(npi);
  1703       if (np->escape_state() < PointsToNode::ArgEscape) {
  1704         np->set_escape_state(PointsToNode::ArgEscape);
  1705         worklist.push(npi);
  1710   GrowableArray<Node*> alloc_worklist;
  1712   // push all NoEscape nodes on the worklist
  1713   for( uint next = 0; next < cg_length; ++next ) {
  1714     int nk = cg_worklist.at(next);
  1715     if (ptnode_adr(nk)->escape_state() == PointsToNode::NoEscape)
  1716       worklist.push(nk);
  1718   // mark all nodes reachable from NoEscape nodes
  1719   while(worklist.length() > 0) {
  1720     PointsToNode* ptn = ptnode_adr(worklist.pop());
  1721     if (ptn->node_type() == PointsToNode::JavaObject)
  1722       has_non_escaping_obj = true; // Non GlobalEscape
  1723     Node* n = ptn->_node;
  1724     if (n->is_Allocate() && ptn->_scalar_replaceable ) {
  1725       // Push scalar replaceable allocations on alloc_worklist
  1726       // for processing in split_unique_types().
  1727       alloc_worklist.append(n);
  1729     uint e_cnt = ptn->edge_count();
  1730     for (uint ei = 0; ei < e_cnt; ei++) {
  1731       uint npi = ptn->edge_target(ei);
  1732       PointsToNode *np = ptnode_adr(npi);
  1733       if (np->escape_state() < PointsToNode::NoEscape) {
  1734         np->set_escape_state(PointsToNode::NoEscape);
  1735         worklist.push(npi);
  1740   _collecting = false;
  1741   assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build");
  1743 #ifndef PRODUCT
  1744   if (PrintEscapeAnalysis) {
  1745     dump(); // Dump ConnectionGraph
  1747 #endif
  1749   bool has_scalar_replaceable_candidates = alloc_worklist.length() > 0;
  1750   if ( has_scalar_replaceable_candidates &&
  1751        C->AliasLevel() >= 3 && EliminateAllocations ) {
  1753     // Now use the escape information to create unique types for
  1754     // scalar replaceable objects.
  1755     split_unique_types(alloc_worklist);
  1757     if (C->failing())  return false;
  1759     C->print_method("After Escape Analysis", 2);
  1761 #ifdef ASSERT
  1762   } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
  1763     tty->print("=== No allocations eliminated for ");
  1764     C->method()->print_short_name();
  1765     if(!EliminateAllocations) {
  1766       tty->print(" since EliminateAllocations is off ===");
  1767     } else if(!has_scalar_replaceable_candidates) {
  1768       tty->print(" since there are no scalar replaceable candidates ===");
  1769     } else if(C->AliasLevel() < 3) {
  1770       tty->print(" since AliasLevel < 3 ===");
  1772     tty->cr();
  1773 #endif
  1775   return has_non_escaping_obj;
  1778 // Adjust escape state after Connection Graph is built.
  1779 void ConnectionGraph::adjust_escape_state(int nidx, PhaseTransform* phase) {
  1780   PointsToNode* ptn = ptnode_adr(nidx);
  1781   Node* n = ptn->_node;
  1782   assert(n->is_AddP(), "Should be called for AddP nodes only");
  1783   // Search for objects which are not scalar replaceable.
  1784   // Mark their escape state as ArgEscape to propagate the state
  1785   // to referenced objects.
  1786   // Note: currently there are no difference in compiler optimizations
  1787   // for ArgEscape objects and NoEscape objects which are not
  1788   // scalar replaceable.
  1790   Compile* C = _compile;
  1792   int offset = ptn->offset();
  1793   Node* base = get_addp_base(n);
  1794   VectorSet* ptset = PointsTo(base);
  1795   int ptset_size = ptset->Size();
  1797   // Check if a oop field's initializing value is recorded and add
  1798   // a corresponding NULL field's value if it is not recorded.
  1799   // Connection Graph does not record a default initialization by NULL
  1800   // captured by Initialize node.
  1801   //
  1802   // Note: it will disable scalar replacement in some cases:
  1803   //
  1804   //    Point p[] = new Point[1];
  1805   //    p[0] = new Point(); // Will be not scalar replaced
  1806   //
  1807   // but it will save us from incorrect optimizations in next cases:
  1808   //
  1809   //    Point p[] = new Point[1];
  1810   //    if ( x ) p[0] = new Point(); // Will be not scalar replaced
  1811   //
  1812   // Do a simple control flow analysis to distinguish above cases.
  1813   //
  1814   if (offset != Type::OffsetBot && ptset_size == 1) {
  1815     uint elem = ptset->getelem(); // Allocation node's index
  1816     // It does not matter if it is not Allocation node since
  1817     // only non-escaping allocations are scalar replaced.
  1818     if (ptnode_adr(elem)->_node->is_Allocate() &&
  1819         ptnode_adr(elem)->escape_state() == PointsToNode::NoEscape) {
  1820       AllocateNode* alloc = ptnode_adr(elem)->_node->as_Allocate();
  1821       InitializeNode* ini = alloc->initialization();
  1823       // Check only oop fields.
  1824       const Type* adr_type = n->as_AddP()->bottom_type();
  1825       BasicType basic_field_type = T_INT;
  1826       if (adr_type->isa_instptr()) {
  1827         ciField* field = C->alias_type(adr_type->isa_instptr())->field();
  1828         if (field != NULL) {
  1829           basic_field_type = field->layout_type();
  1830         } else {
  1831           // Ignore non field load (for example, klass load)
  1833       } else if (adr_type->isa_aryptr()) {
  1834         const Type* elemtype = adr_type->isa_aryptr()->elem();
  1835         basic_field_type = elemtype->array_element_basic_type();
  1836       } else {
  1837         // Raw pointers are used for initializing stores so skip it.
  1838         assert(adr_type->isa_rawptr() && base->is_Proj() &&
  1839                (base->in(0) == alloc),"unexpected pointer type");
  1841       if (basic_field_type == T_OBJECT ||
  1842           basic_field_type == T_NARROWOOP ||
  1843           basic_field_type == T_ARRAY) {
  1844         Node* value = NULL;
  1845         if (ini != NULL) {
  1846           BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT;
  1847           Node* store = ini->find_captured_store(offset, type2aelembytes(ft), phase);
  1848           if (store != NULL && store->is_Store()) {
  1849             value = store->in(MemNode::ValueIn);
  1850           } else if (ptn->edge_count() > 0) { // Are there oop stores?
  1851             // Check for a store which follows allocation without branches.
  1852             // For example, a volatile field store is not collected
  1853             // by Initialize node. TODO: it would be nice to use idom() here.
  1854             for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1855               store = n->fast_out(i);
  1856               if (store->is_Store() && store->in(0) != NULL) {
  1857                 Node* ctrl = store->in(0);
  1858                 while(!(ctrl == ini || ctrl == alloc || ctrl == NULL ||
  1859                         ctrl == C->root() || ctrl == C->top() || ctrl->is_Region() ||
  1860                         ctrl->is_IfTrue() || ctrl->is_IfFalse())) {
  1861                    ctrl = ctrl->in(0);
  1863                 if (ctrl == ini || ctrl == alloc) {
  1864                   value = store->in(MemNode::ValueIn);
  1865                   break;
  1871         if (value == NULL || value != ptnode_adr(value->_idx)->_node) {
  1872           // A field's initializing value was not recorded. Add NULL.
  1873           uint null_idx = UseCompressedOops ? _noop_null : _oop_null;
  1874           add_pointsto_edge(nidx, null_idx);
  1880   // An object is not scalar replaceable if the field which may point
  1881   // to it has unknown offset (unknown element of an array of objects).
  1882   //
  1883   if (offset == Type::OffsetBot) {
  1884     uint e_cnt = ptn->edge_count();
  1885     for (uint ei = 0; ei < e_cnt; ei++) {
  1886       uint npi = ptn->edge_target(ei);
  1887       set_escape_state(npi, PointsToNode::ArgEscape);
  1888       ptnode_adr(npi)->_scalar_replaceable = false;
  1892   // Currently an object is not scalar replaceable if a LoadStore node
  1893   // access its field since the field value is unknown after it.
  1894   //
  1895   bool has_LoadStore = false;
  1896   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
  1897     Node *use = n->fast_out(i);
  1898     if (use->is_LoadStore()) {
  1899       has_LoadStore = true;
  1900       break;
  1903   // An object is not scalar replaceable if the address points
  1904   // to unknown field (unknown element for arrays, offset is OffsetBot).
  1905   //
  1906   // Or the address may point to more then one object. This may produce
  1907   // the false positive result (set scalar_replaceable to false)
  1908   // since the flow-insensitive escape analysis can't separate
  1909   // the case when stores overwrite the field's value from the case
  1910   // when stores happened on different control branches.
  1911   //
  1912   if (ptset_size > 1 || ptset_size != 0 &&
  1913       (has_LoadStore || offset == Type::OffsetBot)) {
  1914     for( VectorSetI j(ptset); j.test(); ++j ) {
  1915       set_escape_state(j.elem, PointsToNode::ArgEscape);
  1916       ptnode_adr(j.elem)->_scalar_replaceable = false;
  1921 void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) {
  1923     switch (call->Opcode()) {
  1924 #ifdef ASSERT
  1925     case Op_Allocate:
  1926     case Op_AllocateArray:
  1927     case Op_Lock:
  1928     case Op_Unlock:
  1929       assert(false, "should be done already");
  1930       break;
  1931 #endif
  1932     case Op_CallLeaf:
  1933     case Op_CallLeafNoFP:
  1935       // Stub calls, objects do not escape but they are not scale replaceable.
  1936       // Adjust escape state for outgoing arguments.
  1937       const TypeTuple * d = call->tf()->domain();
  1938       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1939         const Type* at = d->field_at(i);
  1940         Node *arg = call->in(i)->uncast();
  1941         const Type *aat = phase->type(arg);
  1942         if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr() &&
  1943             ptnode_adr(arg->_idx)->escape_state() < PointsToNode::ArgEscape) {
  1945           assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
  1946                  aat->isa_ptr() != NULL, "expecting an Ptr");
  1947 #ifdef ASSERT
  1948           if (!(call->Opcode() == Op_CallLeafNoFP &&
  1949                 call->as_CallLeaf()->_name != NULL &&
  1950                 (strstr(call->as_CallLeaf()->_name, "arraycopy")  != 0) ||
  1951                 call->as_CallLeaf()->_name != NULL &&
  1952                 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre")  == 0 ||
  1953                  strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 ))
  1954           ) {
  1955             call->dump();
  1956             assert(false, "EA: unexpected CallLeaf");
  1958 #endif
  1959           set_escape_state(arg->_idx, PointsToNode::ArgEscape);
  1960           if (arg->is_AddP()) {
  1961             //
  1962             // The inline_native_clone() case when the arraycopy stub is called
  1963             // after the allocation before Initialize and CheckCastPP nodes.
  1964             //
  1965             // Set AddP's base (Allocate) as not scalar replaceable since
  1966             // pointer to the base (with offset) is passed as argument.
  1967             //
  1968             arg = get_addp_base(arg);
  1970           for( VectorSetI j(PointsTo(arg)); j.test(); ++j ) {
  1971             uint pt = j.elem;
  1972             set_escape_state(pt, PointsToNode::ArgEscape);
  1976       break;
  1979     case Op_CallStaticJava:
  1980     // For a static call, we know exactly what method is being called.
  1981     // Use bytecode estimator to record the call's escape affects
  1983       ciMethod *meth = call->as_CallJava()->method();
  1984       BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
  1985       // fall-through if not a Java method or no analyzer information
  1986       if (call_analyzer != NULL) {
  1987         const TypeTuple * d = call->tf()->domain();
  1988         bool copy_dependencies = false;
  1989         for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  1990           const Type* at = d->field_at(i);
  1991           int k = i - TypeFunc::Parms;
  1992           Node *arg = call->in(i)->uncast();
  1994           if (at->isa_oopptr() != NULL &&
  1995               ptnode_adr(arg->_idx)->escape_state() < PointsToNode::GlobalEscape) {
  1997             bool global_escapes = false;
  1998             bool fields_escapes = false;
  1999             if (!call_analyzer->is_arg_stack(k)) {
  2000               // The argument global escapes, mark everything it could point to
  2001               set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
  2002               global_escapes = true;
  2003             } else {
  2004               if (!call_analyzer->is_arg_local(k)) {
  2005                 // The argument itself doesn't escape, but any fields might
  2006                 fields_escapes = true;
  2008               set_escape_state(arg->_idx, PointsToNode::ArgEscape);
  2009               copy_dependencies = true;
  2012             for( VectorSetI j(PointsTo(arg)); j.test(); ++j ) {
  2013               uint pt = j.elem;
  2014               if (global_escapes) {
  2015                 //The argument global escapes, mark everything it could point to
  2016                 set_escape_state(pt, PointsToNode::GlobalEscape);
  2017               } else {
  2018                 if (fields_escapes) {
  2019                   // The argument itself doesn't escape, but any fields might
  2020                   add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
  2022                 set_escape_state(pt, PointsToNode::ArgEscape);
  2027         if (copy_dependencies)
  2028           call_analyzer->copy_dependencies(_compile->dependencies());
  2029         break;
  2033     default:
  2034     // Fall-through here if not a Java method or no analyzer information
  2035     // or some other type of call, assume the worst case: all arguments
  2036     // globally escape.
  2038       // adjust escape state for  outgoing arguments
  2039       const TypeTuple * d = call->tf()->domain();
  2040       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  2041         const Type* at = d->field_at(i);
  2042         if (at->isa_oopptr() != NULL) {
  2043           Node *arg = call->in(i)->uncast();
  2044           set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
  2045           for( VectorSetI j(PointsTo(arg)); j.test(); ++j ) {
  2046             uint pt = j.elem;
  2047             set_escape_state(pt, PointsToNode::GlobalEscape);
  2054 void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) {
  2055   CallNode   *call = resproj->in(0)->as_Call();
  2056   uint    call_idx = call->_idx;
  2057   uint resproj_idx = resproj->_idx;
  2059   switch (call->Opcode()) {
  2060     case Op_Allocate:
  2062       Node *k = call->in(AllocateNode::KlassNode);
  2063       const TypeKlassPtr *kt = k->bottom_type()->isa_klassptr();
  2064       assert(kt != NULL, "TypeKlassPtr  required.");
  2065       ciKlass* cik = kt->klass();
  2067       PointsToNode::EscapeState es;
  2068       uint edge_to;
  2069       if (cik->is_subclass_of(_compile->env()->Thread_klass()) ||
  2070          !cik->is_instance_klass() || // StressReflectiveCode
  2071           cik->as_instance_klass()->has_finalizer()) {
  2072         es = PointsToNode::GlobalEscape;
  2073         edge_to = _phantom_object; // Could not be worse
  2074       } else {
  2075         es = PointsToNode::NoEscape;
  2076         edge_to = call_idx;
  2078       set_escape_state(call_idx, es);
  2079       add_pointsto_edge(resproj_idx, edge_to);
  2080       _processed.set(resproj_idx);
  2081       break;
  2084     case Op_AllocateArray:
  2087       Node *k = call->in(AllocateNode::KlassNode);
  2088       const TypeKlassPtr *kt = k->bottom_type()->isa_klassptr();
  2089       assert(kt != NULL, "TypeKlassPtr  required.");
  2090       ciKlass* cik = kt->klass();
  2092       PointsToNode::EscapeState es;
  2093       uint edge_to;
  2094       if (!cik->is_array_klass()) { // StressReflectiveCode
  2095         es = PointsToNode::GlobalEscape;
  2096         edge_to = _phantom_object;
  2097       } else {
  2098         es = PointsToNode::NoEscape;
  2099         edge_to = call_idx;
  2100         int length = call->in(AllocateNode::ALength)->find_int_con(-1);
  2101         if (length < 0 || length > EliminateAllocationArraySizeLimit) {
  2102           // Not scalar replaceable if the length is not constant or too big.
  2103           ptnode_adr(call_idx)->_scalar_replaceable = false;
  2106       set_escape_state(call_idx, es);
  2107       add_pointsto_edge(resproj_idx, edge_to);
  2108       _processed.set(resproj_idx);
  2109       break;
  2112     case Op_CallStaticJava:
  2113     // For a static call, we know exactly what method is being called.
  2114     // Use bytecode estimator to record whether the call's return value escapes
  2116       bool done = true;
  2117       const TypeTuple *r = call->tf()->range();
  2118       const Type* ret_type = NULL;
  2120       if (r->cnt() > TypeFunc::Parms)
  2121         ret_type = r->field_at(TypeFunc::Parms);
  2123       // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
  2124       //        _multianewarray functions return a TypeRawPtr.
  2125       if (ret_type == NULL || ret_type->isa_ptr() == NULL) {
  2126         _processed.set(resproj_idx);
  2127         break;  // doesn't return a pointer type
  2129       ciMethod *meth = call->as_CallJava()->method();
  2130       const TypeTuple * d = call->tf()->domain();
  2131       if (meth == NULL) {
  2132         // not a Java method, assume global escape
  2133         set_escape_state(call_idx, PointsToNode::GlobalEscape);
  2134         add_pointsto_edge(resproj_idx, _phantom_object);
  2135       } else {
  2136         BCEscapeAnalyzer *call_analyzer = meth->get_bcea();
  2137         bool copy_dependencies = false;
  2139         if (call_analyzer->is_return_allocated()) {
  2140           // Returns a newly allocated unescaped object, simply
  2141           // update dependency information.
  2142           // Mark it as NoEscape so that objects referenced by
  2143           // it's fields will be marked as NoEscape at least.
  2144           set_escape_state(call_idx, PointsToNode::NoEscape);
  2145           add_pointsto_edge(resproj_idx, call_idx);
  2146           copy_dependencies = true;
  2147         } else if (call_analyzer->is_return_local()) {
  2148           // determine whether any arguments are returned
  2149           set_escape_state(call_idx, PointsToNode::NoEscape);
  2150           bool ret_arg = false;
  2151           for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  2152             const Type* at = d->field_at(i);
  2154             if (at->isa_oopptr() != NULL) {
  2155               Node *arg = call->in(i)->uncast();
  2157               if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
  2158                 ret_arg = true;
  2159                 PointsToNode *arg_esp = ptnode_adr(arg->_idx);
  2160                 if (arg_esp->node_type() == PointsToNode::UnknownType)
  2161                   done = false;
  2162                 else if (arg_esp->node_type() == PointsToNode::JavaObject)
  2163                   add_pointsto_edge(resproj_idx, arg->_idx);
  2164                 else
  2165                   add_deferred_edge(resproj_idx, arg->_idx);
  2166                 arg_esp->_hidden_alias = true;
  2170           if (done && !ret_arg) {
  2171             // Returns unknown object.
  2172             set_escape_state(call_idx, PointsToNode::GlobalEscape);
  2173             add_pointsto_edge(resproj_idx, _phantom_object);
  2175           copy_dependencies = true;
  2176         } else {
  2177           set_escape_state(call_idx, PointsToNode::GlobalEscape);
  2178           add_pointsto_edge(resproj_idx, _phantom_object);
  2179           for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
  2180             const Type* at = d->field_at(i);
  2181             if (at->isa_oopptr() != NULL) {
  2182               Node *arg = call->in(i)->uncast();
  2183               PointsToNode *arg_esp = ptnode_adr(arg->_idx);
  2184               arg_esp->_hidden_alias = true;
  2188         if (copy_dependencies)
  2189           call_analyzer->copy_dependencies(_compile->dependencies());
  2191       if (done)
  2192         _processed.set(resproj_idx);
  2193       break;
  2196     default:
  2197     // Some other type of call, assume the worst case that the
  2198     // returned value, if any, globally escapes.
  2200       const TypeTuple *r = call->tf()->range();
  2201       if (r->cnt() > TypeFunc::Parms) {
  2202         const Type* ret_type = r->field_at(TypeFunc::Parms);
  2204         // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
  2205         //        _multianewarray functions return a TypeRawPtr.
  2206         if (ret_type->isa_ptr() != NULL) {
  2207           set_escape_state(call_idx, PointsToNode::GlobalEscape);
  2208           add_pointsto_edge(resproj_idx, _phantom_object);
  2211       _processed.set(resproj_idx);
  2216 // Populate Connection Graph with Ideal nodes and create simple
  2217 // connection graph edges (do not need to check the node_type of inputs
  2218 // or to call PointsTo() to walk the connection graph).
  2219 void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) {
  2220   if (_processed.test(n->_idx))
  2221     return; // No need to redefine node's state.
  2223   if (n->is_Call()) {
  2224     // Arguments to allocation and locking don't escape.
  2225     if (n->is_Allocate()) {
  2226       add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true);
  2227       record_for_optimizer(n);
  2228     } else if (n->is_Lock() || n->is_Unlock()) {
  2229       // Put Lock and Unlock nodes on IGVN worklist to process them during
  2230       // the first IGVN optimization when escape information is still available.
  2231       record_for_optimizer(n);
  2232       _processed.set(n->_idx);
  2233     } else {
  2234       // Don't mark as processed since call's arguments have to be processed.
  2235       PointsToNode::NodeType nt = PointsToNode::UnknownType;
  2236       PointsToNode::EscapeState es = PointsToNode::UnknownEscape;
  2238       // Check if a call returns an object.
  2239       const TypeTuple *r = n->as_Call()->tf()->range();
  2240       if (r->cnt() > TypeFunc::Parms &&
  2241           r->field_at(TypeFunc::Parms)->isa_ptr() &&
  2242           n->as_Call()->proj_out(TypeFunc::Parms) != NULL) {
  2243         nt = PointsToNode::JavaObject;
  2244         if (!n->is_CallStaticJava()) {
  2245           // Since the called mathod is statically unknown assume
  2246           // the worst case that the returned value globally escapes.
  2247           es = PointsToNode::GlobalEscape;
  2250       add_node(n, nt, es, false);
  2252     return;
  2255   // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
  2256   // ThreadLocal has RawPrt type.
  2257   switch (n->Opcode()) {
  2258     case Op_AddP:
  2260       add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false);
  2261       break;
  2263     case Op_CastX2P:
  2264     { // "Unsafe" memory access.
  2265       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  2266       break;
  2268     case Op_CastPP:
  2269     case Op_CheckCastPP:
  2270     case Op_EncodeP:
  2271     case Op_DecodeN:
  2273       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2274       int ti = n->in(1)->_idx;
  2275       PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2276       if (nt == PointsToNode::UnknownType) {
  2277         _delayed_worklist.push(n); // Process it later.
  2278         break;
  2279       } else if (nt == PointsToNode::JavaObject) {
  2280         add_pointsto_edge(n->_idx, ti);
  2281       } else {
  2282         add_deferred_edge(n->_idx, ti);
  2284       _processed.set(n->_idx);
  2285       break;
  2287     case Op_ConP:
  2289       // assume all pointer constants globally escape except for null
  2290       PointsToNode::EscapeState es;
  2291       if (phase->type(n) == TypePtr::NULL_PTR)
  2292         es = PointsToNode::NoEscape;
  2293       else
  2294         es = PointsToNode::GlobalEscape;
  2296       add_node(n, PointsToNode::JavaObject, es, true);
  2297       break;
  2299     case Op_ConN:
  2301       // assume all narrow oop constants globally escape except for null
  2302       PointsToNode::EscapeState es;
  2303       if (phase->type(n) == TypeNarrowOop::NULL_PTR)
  2304         es = PointsToNode::NoEscape;
  2305       else
  2306         es = PointsToNode::GlobalEscape;
  2308       add_node(n, PointsToNode::JavaObject, es, true);
  2309       break;
  2311     case Op_CreateEx:
  2313       // assume that all exception objects globally escape
  2314       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  2315       break;
  2317     case Op_LoadKlass:
  2318     case Op_LoadNKlass:
  2320       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
  2321       break;
  2323     case Op_LoadP:
  2324     case Op_LoadN:
  2326       const Type *t = phase->type(n);
  2327       if (t->make_ptr() == NULL) {
  2328         _processed.set(n->_idx);
  2329         return;
  2331       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2332       break;
  2334     case Op_Parm:
  2336       _processed.set(n->_idx); // No need to redefine it state.
  2337       uint con = n->as_Proj()->_con;
  2338       if (con < TypeFunc::Parms)
  2339         return;
  2340       const Type *t = n->in(0)->as_Start()->_domain->field_at(con);
  2341       if (t->isa_ptr() == NULL)
  2342         return;
  2343       // We have to assume all input parameters globally escape
  2344       // (Note: passing 'false' since _processed is already set).
  2345       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false);
  2346       break;
  2348     case Op_Phi:
  2350       const Type *t = n->as_Phi()->type();
  2351       if (t->make_ptr() == NULL) {
  2352         // nothing to do if not an oop or narrow oop
  2353         _processed.set(n->_idx);
  2354         return;
  2356       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2357       uint i;
  2358       for (i = 1; i < n->req() ; i++) {
  2359         Node* in = n->in(i);
  2360         if (in == NULL)
  2361           continue;  // ignore NULL
  2362         in = in->uncast();
  2363         if (in->is_top() || in == n)
  2364           continue;  // ignore top or inputs which go back this node
  2365         int ti = in->_idx;
  2366         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2367         if (nt == PointsToNode::UnknownType) {
  2368           break;
  2369         } else if (nt == PointsToNode::JavaObject) {
  2370           add_pointsto_edge(n->_idx, ti);
  2371         } else {
  2372           add_deferred_edge(n->_idx, ti);
  2375       if (i >= n->req())
  2376         _processed.set(n->_idx);
  2377       else
  2378         _delayed_worklist.push(n);
  2379       break;
  2381     case Op_Proj:
  2383       // we are only interested in the oop result projection from a call
  2384       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
  2385         const TypeTuple *r = n->in(0)->as_Call()->tf()->range();
  2386         assert(r->cnt() > TypeFunc::Parms, "sanity");
  2387         if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
  2388           add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
  2389           int ti = n->in(0)->_idx;
  2390           // The call may not be registered yet (since not all its inputs are registered)
  2391           // if this is the projection from backbranch edge of Phi.
  2392           if (ptnode_adr(ti)->node_type() != PointsToNode::UnknownType) {
  2393             process_call_result(n->as_Proj(), phase);
  2395           if (!_processed.test(n->_idx)) {
  2396             // The call's result may need to be processed later if the call
  2397             // returns it's argument and the argument is not processed yet.
  2398             _delayed_worklist.push(n);
  2400           break;
  2403       _processed.set(n->_idx);
  2404       break;
  2406     case Op_Return:
  2408       if( n->req() > TypeFunc::Parms &&
  2409           phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
  2410         // Treat Return value as LocalVar with GlobalEscape escape state.
  2411         add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false);
  2412         int ti = n->in(TypeFunc::Parms)->_idx;
  2413         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2414         if (nt == PointsToNode::UnknownType) {
  2415           _delayed_worklist.push(n); // Process it later.
  2416           break;
  2417         } else if (nt == PointsToNode::JavaObject) {
  2418           add_pointsto_edge(n->_idx, ti);
  2419         } else {
  2420           add_deferred_edge(n->_idx, ti);
  2423       _processed.set(n->_idx);
  2424       break;
  2426     case Op_StoreP:
  2427     case Op_StoreN:
  2429       const Type *adr_type = phase->type(n->in(MemNode::Address));
  2430       adr_type = adr_type->make_ptr();
  2431       if (adr_type->isa_oopptr()) {
  2432         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2433       } else {
  2434         Node* adr = n->in(MemNode::Address);
  2435         if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL &&
  2436             adr->in(AddPNode::Address)->is_Proj() &&
  2437             adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
  2438           add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2439           // We are computing a raw address for a store captured
  2440           // by an Initialize compute an appropriate address type.
  2441           int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
  2442           assert(offs != Type::OffsetBot, "offset must be a constant");
  2443         } else {
  2444           _processed.set(n->_idx);
  2445           return;
  2448       break;
  2450     case Op_StorePConditional:
  2451     case Op_CompareAndSwapP:
  2452     case Op_CompareAndSwapN:
  2454       const Type *adr_type = phase->type(n->in(MemNode::Address));
  2455       adr_type = adr_type->make_ptr();
  2456       if (adr_type->isa_oopptr()) {
  2457         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2458       } else {
  2459         _processed.set(n->_idx);
  2460         return;
  2462       break;
  2464     case Op_AryEq:
  2465     case Op_StrComp:
  2466     case Op_StrEquals:
  2467     case Op_StrIndexOf:
  2469       // char[] arrays passed to string intrinsics are not scalar replaceable.
  2470       add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
  2471       break;
  2473     case Op_ThreadLocal:
  2475       add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true);
  2476       break;
  2478     default:
  2480       // nothing to do
  2482   return;
  2485 void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) {
  2486   uint n_idx = n->_idx;
  2487   assert(ptnode_adr(n_idx)->_node != NULL, "node should be registered");
  2489   // Don't set processed bit for AddP, LoadP, StoreP since
  2490   // they may need more then one pass to process.
  2491   // Also don't mark as processed Call nodes since their
  2492   // arguments may need more then one pass to process.
  2493   if (_processed.test(n_idx))
  2494     return; // No need to redefine node's state.
  2496   if (n->is_Call()) {
  2497     CallNode *call = n->as_Call();
  2498     process_call_arguments(call, phase);
  2499     return;
  2502   switch (n->Opcode()) {
  2503     case Op_AddP:
  2505       Node *base = get_addp_base(n);
  2506       // Create a field edge to this node from everything base could point to.
  2507       for( VectorSetI i(PointsTo(base)); i.test(); ++i ) {
  2508         uint pt = i.elem;
  2509         add_field_edge(pt, n_idx, address_offset(n, phase));
  2511       break;
  2513     case Op_CastX2P:
  2515       assert(false, "Op_CastX2P");
  2516       break;
  2518     case Op_CastPP:
  2519     case Op_CheckCastPP:
  2520     case Op_EncodeP:
  2521     case Op_DecodeN:
  2523       int ti = n->in(1)->_idx;
  2524       assert(ptnode_adr(ti)->node_type() != PointsToNode::UnknownType, "all nodes should be registered");
  2525       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
  2526         add_pointsto_edge(n_idx, ti);
  2527       } else {
  2528         add_deferred_edge(n_idx, ti);
  2530       _processed.set(n_idx);
  2531       break;
  2533     case Op_ConP:
  2535       assert(false, "Op_ConP");
  2536       break;
  2538     case Op_ConN:
  2540       assert(false, "Op_ConN");
  2541       break;
  2543     case Op_CreateEx:
  2545       assert(false, "Op_CreateEx");
  2546       break;
  2548     case Op_LoadKlass:
  2549     case Op_LoadNKlass:
  2551       assert(false, "Op_LoadKlass");
  2552       break;
  2554     case Op_LoadP:
  2555     case Op_LoadN:
  2557       const Type *t = phase->type(n);
  2558 #ifdef ASSERT
  2559       if (t->make_ptr() == NULL)
  2560         assert(false, "Op_LoadP");
  2561 #endif
  2563       Node* adr = n->in(MemNode::Address)->uncast();
  2564       Node* adr_base;
  2565       if (adr->is_AddP()) {
  2566         adr_base = get_addp_base(adr);
  2567       } else {
  2568         adr_base = adr;
  2571       // For everything "adr_base" could point to, create a deferred edge from
  2572       // this node to each field with the same offset.
  2573       int offset = address_offset(adr, phase);
  2574       for( VectorSetI i(PointsTo(adr_base)); i.test(); ++i ) {
  2575         uint pt = i.elem;
  2576         add_deferred_edge_to_fields(n_idx, pt, offset);
  2578       break;
  2580     case Op_Parm:
  2582       assert(false, "Op_Parm");
  2583       break;
  2585     case Op_Phi:
  2587 #ifdef ASSERT
  2588       const Type *t = n->as_Phi()->type();
  2589       if (t->make_ptr() == NULL)
  2590         assert(false, "Op_Phi");
  2591 #endif
  2592       for (uint i = 1; i < n->req() ; i++) {
  2593         Node* in = n->in(i);
  2594         if (in == NULL)
  2595           continue;  // ignore NULL
  2596         in = in->uncast();
  2597         if (in->is_top() || in == n)
  2598           continue;  // ignore top or inputs which go back this node
  2599         int ti = in->_idx;
  2600         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
  2601         assert(nt != PointsToNode::UnknownType, "all nodes should be known");
  2602         if (nt == PointsToNode::JavaObject) {
  2603           add_pointsto_edge(n_idx, ti);
  2604         } else {
  2605           add_deferred_edge(n_idx, ti);
  2608       _processed.set(n_idx);
  2609       break;
  2611     case Op_Proj:
  2613       // we are only interested in the oop result projection from a call
  2614       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
  2615         assert(ptnode_adr(n->in(0)->_idx)->node_type() != PointsToNode::UnknownType,
  2616                "all nodes should be registered");
  2617         const TypeTuple *r = n->in(0)->as_Call()->tf()->range();
  2618         assert(r->cnt() > TypeFunc::Parms, "sanity");
  2619         if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
  2620           process_call_result(n->as_Proj(), phase);
  2621           assert(_processed.test(n_idx), "all call results should be processed");
  2622           break;
  2625       assert(false, "Op_Proj");
  2626       break;
  2628     case Op_Return:
  2630 #ifdef ASSERT
  2631       if( n->req() <= TypeFunc::Parms ||
  2632           !phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
  2633         assert(false, "Op_Return");
  2635 #endif
  2636       int ti = n->in(TypeFunc::Parms)->_idx;
  2637       assert(ptnode_adr(ti)->node_type() != PointsToNode::UnknownType, "node should be registered");
  2638       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
  2639         add_pointsto_edge(n_idx, ti);
  2640       } else {
  2641         add_deferred_edge(n_idx, ti);
  2643       _processed.set(n_idx);
  2644       break;
  2646     case Op_StoreP:
  2647     case Op_StoreN:
  2648     case Op_StorePConditional:
  2649     case Op_CompareAndSwapP:
  2650     case Op_CompareAndSwapN:
  2652       Node *adr = n->in(MemNode::Address);
  2653       const Type *adr_type = phase->type(adr)->make_ptr();
  2654 #ifdef ASSERT
  2655       if (!adr_type->isa_oopptr())
  2656         assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP");
  2657 #endif
  2659       assert(adr->is_AddP(), "expecting an AddP");
  2660       Node *adr_base = get_addp_base(adr);
  2661       Node *val = n->in(MemNode::ValueIn)->uncast();
  2662       // For everything "adr_base" could point to, create a deferred edge
  2663       // to "val" from each field with the same offset.
  2664       for( VectorSetI i(PointsTo(adr_base)); i.test(); ++i ) {
  2665         uint pt = i.elem;
  2666         add_edge_from_fields(pt, val->_idx, address_offset(adr, phase));
  2668       break;
  2670     case Op_AryEq:
  2671     case Op_StrComp:
  2672     case Op_StrEquals:
  2673     case Op_StrIndexOf:
  2675       // char[] arrays passed to string intrinsic do not escape but
  2676       // they are not scalar replaceable. Adjust escape state for them.
  2677       // Start from in(2) edge since in(1) is memory edge.
  2678       for (uint i = 2; i < n->req(); i++) {
  2679         Node* adr = n->in(i)->uncast();
  2680         const Type *at = phase->type(adr);
  2681         if (!adr->is_top() && at->isa_ptr()) {
  2682           assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
  2683                  at->isa_ptr() != NULL, "expecting an Ptr");
  2684           if (adr->is_AddP()) {
  2685             adr = get_addp_base(adr);
  2687           // Mark as ArgEscape everything "adr" could point to.
  2688           set_escape_state(adr->_idx, PointsToNode::ArgEscape);
  2691       _processed.set(n_idx);
  2692       break;
  2694     case Op_ThreadLocal:
  2696       assert(false, "Op_ThreadLocal");
  2697       break;
  2699     default:
  2700       // This method should be called only for EA specific nodes.
  2701       ShouldNotReachHere();
  2705 #ifndef PRODUCT
  2706 void ConnectionGraph::dump() {
  2707   bool first = true;
  2709   uint size = nodes_size();
  2710   for (uint ni = 0; ni < size; ni++) {
  2711     PointsToNode *ptn = ptnode_adr(ni);
  2712     PointsToNode::NodeType ptn_type = ptn->node_type();
  2714     if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL)
  2715       continue;
  2716     PointsToNode::EscapeState es = escape_state(ptn->_node);
  2717     if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) {
  2718       if (first) {
  2719         tty->cr();
  2720         tty->print("======== Connection graph for ");
  2721         _compile->method()->print_short_name();
  2722         tty->cr();
  2723         first = false;
  2725       tty->print("%6d ", ni);
  2726       ptn->dump();
  2727       // Print all locals which reference this allocation
  2728       for (uint li = ni; li < size; li++) {
  2729         PointsToNode *ptn_loc = ptnode_adr(li);
  2730         PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type();
  2731         if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL &&
  2732              ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) {
  2733           ptnode_adr(li)->dump(false);
  2736       if (Verbose) {
  2737         // Print all fields which reference this allocation
  2738         for (uint i = 0; i < ptn->edge_count(); i++) {
  2739           uint ei = ptn->edge_target(i);
  2740           ptnode_adr(ei)->dump(false);
  2743       tty->cr();
  2747 #endif

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