jdk8-mips64-public/hotspot: src/share/vm/opto/escape.cpp@cc81b9c09bbb (annotated)

src/share/vm/opto/escape.cpp@cc81b9c09bbb (annotated)

src/share/vm/opto/escape.cpp

Mon, 28 Nov 2011 15:46:31 -0800

author: kvn
date: Mon, 28 Nov 2011 15:46:31 -0800
changeset 3318: cc81b9c09bbb
parent 3311: 1bd45abaa507
child 3392: 1dc233a8c7fe
permissions: -rw-r--r--

7112478: after 7105605 JRuby bench_define_method_methods.rb fails with NPE
Summary: Fixed several EA issues with Connection Graph construction.
Reviewed-by: never, twisti

 /*
  * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "ci/bcEscapeAnalyzer.hpp"
 #include "libadt/vectset.hpp"
 #include "memory/allocation.hpp"
 #include "opto/c2compiler.hpp"
 #include "opto/callnode.hpp"
 #include "opto/cfgnode.hpp"
 #include "opto/compile.hpp"
 #include "opto/escape.hpp"
 #include "opto/phaseX.hpp"
 #include "opto/rootnode.hpp"
 void PointsToNode::add_edge(uint targIdx, PointsToNode::EdgeType et) {
   uint v = (targIdx << EdgeShift) + ((uint) et);
   if (_edges == NULL) {
      Arena *a = Compile::current()->comp_arena();
     _edges = new(a) GrowableArray<uint>(a, INITIAL_EDGE_COUNT, 0, 0);
   }
   _edges->append_if_missing(v);
 }
 void PointsToNode::remove_edge(uint targIdx, PointsToNode::EdgeType et) {
   uint v = (targIdx << EdgeShift) + ((uint) et);
   _edges->remove(v);
 }
 #ifndef PRODUCT
 static const char *node_type_names[] = {
   "UnknownType",
   "JavaObject",
   "LocalVar",
   "Field"
 };
 static const char *esc_names[] = {
   "UnknownEscape",
   "NoEscape",
   "ArgEscape",
   "GlobalEscape"
 };
 static const char *edge_type_suffix[] = {
  "?", // UnknownEdge
  "P", // PointsToEdge
  "D", // DeferredEdge
  "F"  // FieldEdge
 };
 void PointsToNode::dump(bool print_state) const {
   NodeType nt = node_type();
   tty->print("%s ", node_type_names[(int) nt]);
   if (print_state) {
     EscapeState es = escape_state();
     tty->print("%s %s ", esc_names[(int) es], _scalar_replaceable ? "":"NSR");
   }
   tty->print("[[");
   for (uint i = 0; i < edge_count(); i++) {
     tty->print(" %d%s", edge_target(i), edge_type_suffix[(int) edge_type(i)]);
   }
   tty->print("]]  ");
   if (_node == NULL)
     tty->print_cr("<null>");
   else
     _node->dump();
 }
 #endif
 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) :
   _nodes(C->comp_arena(), C->unique(), C->unique(), PointsToNode()),
   _processed(C->comp_arena()),
   pt_ptset(C->comp_arena()),
   pt_visited(C->comp_arena()),
   pt_worklist(C->comp_arena(), 4, 0, 0),
   _collecting(true),
   _progress(false),
   _compile(C),
   _igvn(igvn),
   _node_map(C->comp_arena()) {
   _phantom_object = C->top()->_idx,
   add_node(C->top(), PointsToNode::JavaObject, PointsToNode::GlobalEscape,true);
   // Add ConP(#NULL) and ConN(#NULL) nodes.
   Node* oop_null = igvn->zerocon(T_OBJECT);
   _oop_null = oop_null->_idx;
   assert(_oop_null < nodes_size(), "should be created already");
   add_node(oop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
   if (UseCompressedOops) {
     Node* noop_null = igvn->zerocon(T_NARROWOOP);
     _noop_null = noop_null->_idx;
     assert(_noop_null < nodes_size(), "should be created already");
     add_node(noop_null, PointsToNode::JavaObject, PointsToNode::NoEscape, true);
   } else {
     _noop_null = _oop_null; // Should be initialized
   }
   _pcmp_neq = NULL; // Should be initialized
   _pcmp_eq  = NULL;
 }
 void ConnectionGraph::add_pointsto_edge(uint from_i, uint to_i) {
   PointsToNode *f = ptnode_adr(from_i);
   PointsToNode *t = ptnode_adr(to_i);
   assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
   assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of PointsTo edge");
   assert(t->node_type() == PointsToNode::JavaObject, "invalid destination of PointsTo edge");
   if (to_i == _phantom_object) { // Quick test for most common object
     if (f->has_unknown_ptr()) {
       return;
     } else {
       f->set_has_unknown_ptr();
     }
   }
   add_edge(f, to_i, PointsToNode::PointsToEdge);
 }
 void ConnectionGraph::add_deferred_edge(uint from_i, uint to_i) {
   PointsToNode *f = ptnode_adr(from_i);
   PointsToNode *t = ptnode_adr(to_i);
   assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
   assert(f->node_type() == PointsToNode::LocalVar || f->node_type() == PointsToNode::Field, "invalid source of Deferred edge");
   assert(t->node_type() == PointsToNode::LocalVar || t->node_type() == PointsToNode::Field, "invalid destination of Deferred edge");
   // don't add a self-referential edge, this can occur during removal of
   // deferred edges
   if (from_i != to_i)
     add_edge(f, to_i, PointsToNode::DeferredEdge);
 }
 int ConnectionGraph::address_offset(Node* adr, PhaseTransform *phase) {
   const Type *adr_type = phase->type(adr);
   if (adr->is_AddP() && adr_type->isa_oopptr() == NULL &&
       adr->in(AddPNode::Address)->is_Proj() &&
       adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
     // We are computing a raw address for a store captured by an Initialize
     // compute an appropriate address type. AddP cases #3 and #5 (see below).
     int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
     assert(offs != Type::OffsetBot ||
            adr->in(AddPNode::Address)->in(0)->is_AllocateArray(),
            "offset must be a constant or it is initialization of array");
     return offs;
   }
   const TypePtr *t_ptr = adr_type->isa_ptr();
   assert(t_ptr != NULL, "must be a pointer type");
   return t_ptr->offset();
 }
 void ConnectionGraph::add_field_edge(uint from_i, uint to_i, int offset) {
   // Don't add fields to NULL pointer.
   if (is_null_ptr(from_i))
     return;
   PointsToNode *f = ptnode_adr(from_i);
   PointsToNode *t = ptnode_adr(to_i);
   assert(f->node_type() != PointsToNode::UnknownType && t->node_type() != PointsToNode::UnknownType, "node types must be set");
   assert(f->node_type() == PointsToNode::JavaObject, "invalid destination of Field edge");
   assert(t->node_type() == PointsToNode::Field, "invalid destination of Field edge");
   assert (t->offset() == -1 || t->offset() == offset, "conflicting field offsets");
   t->set_offset(offset);
   add_edge(f, to_i, PointsToNode::FieldEdge);
 }
 void ConnectionGraph::set_escape_state(uint ni, PointsToNode::EscapeState es) {
   // Don't change non-escaping state of NULL pointer.
   if (is_null_ptr(ni))
     return;
   PointsToNode *npt = ptnode_adr(ni);
   PointsToNode::EscapeState old_es = npt->escape_state();
   if (es > old_es)
     npt->set_escape_state(es);
 }
 void ConnectionGraph::add_node(Node *n, PointsToNode::NodeType nt,
                                PointsToNode::EscapeState es, bool done) {
   PointsToNode* ptadr = ptnode_adr(n->_idx);
   ptadr->_node = n;
   ptadr->set_node_type(nt);
   // inline set_escape_state(idx, es);
   PointsToNode::EscapeState old_es = ptadr->escape_state();
   if (es > old_es)
     ptadr->set_escape_state(es);
   if (done)
     _processed.set(n->_idx);
 }
 PointsToNode::EscapeState ConnectionGraph::escape_state(Node *n) {
   uint idx = n->_idx;
   PointsToNode::EscapeState es;
   // If we are still collecting or there were no non-escaping allocations
   // we don't know the answer yet
   if (_collecting)
     return PointsToNode::UnknownEscape;
   // if the node was created after the escape computation, return
   // UnknownEscape
   if (idx >= nodes_size())
     return PointsToNode::UnknownEscape;
   es = ptnode_adr(idx)->escape_state();
   // if we have already computed a value, return it
   if (es != PointsToNode::UnknownEscape &&
       ptnode_adr(idx)->node_type() == PointsToNode::JavaObject)
     return es;
   // PointsTo() calls n->uncast() which can return a new ideal node.
   if (n->uncast()->_idx >= nodes_size())
     return PointsToNode::UnknownEscape;
   PointsToNode::EscapeState orig_es = es;
   // compute max escape state of anything this node could point to
   for(VectorSetI i(PointsTo(n)); i.test() && es != PointsToNode::GlobalEscape; ++i) {
     uint pt = i.elem;
     PointsToNode::EscapeState pes = ptnode_adr(pt)->escape_state();
     if (pes > es)
       es = pes;
   }
   if (orig_es != es) {
     // cache the computed escape state
     assert(es > orig_es, "should have computed an escape state");
     set_escape_state(idx, es);
   } // orig_es could be PointsToNode::UnknownEscape
   return es;
 }
 VectorSet* ConnectionGraph::PointsTo(Node * n) {
   pt_ptset.Reset();
   pt_visited.Reset();
   pt_worklist.clear();
 #ifdef ASSERT
   Node *orig_n = n;
 #endif
   n = n->uncast();
   PointsToNode* npt = ptnode_adr(n->_idx);
   // If we have a JavaObject, return just that object
   if (npt->node_type() == PointsToNode::JavaObject) {
     pt_ptset.set(n->_idx);
     return &pt_ptset;
   }
 #ifdef ASSERT
   if (npt->_node == NULL) {
     if (orig_n != n)
       orig_n->dump();
     n->dump();
     assert(npt->_node != NULL, "unregistered node");
   }
 #endif
   pt_worklist.push(n->_idx);
   while(pt_worklist.length() > 0) {
     int ni = pt_worklist.pop();
     if (pt_visited.test_set(ni))
       continue;
     PointsToNode* pn = ptnode_adr(ni);
     // ensure that all inputs of a Phi have been processed
     assert(!_collecting || !pn->_node->is_Phi() || _processed.test(ni),"");
     int edges_processed = 0;
     uint e_cnt = pn->edge_count();
     for (uint e = 0; e < e_cnt; e++) {
       uint etgt = pn->edge_target(e);
       PointsToNode::EdgeType et = pn->edge_type(e);
       if (et == PointsToNode::PointsToEdge) {
         pt_ptset.set(etgt);
         edges_processed++;
       } else if (et == PointsToNode::DeferredEdge) {
         pt_worklist.push(etgt);
         edges_processed++;
       } else {
         assert(false,"neither PointsToEdge or DeferredEdge");
       }
     }
     if (edges_processed == 0) {
       // no deferred or pointsto edges found.  Assume the value was set
       // outside this method.  Add the phantom object to the pointsto set.
       pt_ptset.set(_phantom_object);
     }
   }
   return &pt_ptset;
 }
 void ConnectionGraph::remove_deferred(uint ni, GrowableArray<uint>* deferred_edges, VectorSet* visited) {
   // This method is most expensive during ConnectionGraph construction.
   // Reuse vectorSet and an additional growable array for deferred edges.
   deferred_edges->clear();
   visited->Reset();
   visited->set(ni);
   PointsToNode *ptn = ptnode_adr(ni);
   assert(ptn->node_type() == PointsToNode::LocalVar ||
          ptn->node_type() == PointsToNode::Field, "sanity");
   assert(ptn->edge_count() != 0, "should have at least phantom_object");
   // Mark current edges as visited and move deferred edges to separate array.
   for (uint i = 0; i < ptn->edge_count(); ) {
     uint t = ptn->edge_target(i);
 #ifdef ASSERT
     assert(!visited->test_set(t), "expecting no duplications");
 #else
     visited->set(t);
 #endif
     if (ptn->edge_type(i) == PointsToNode::DeferredEdge) {
       ptn->remove_edge(t, PointsToNode::DeferredEdge);
       deferred_edges->append(t);
     } else {
       i++;
     }
   }
   for (int next = 0; next < deferred_edges->length(); ++next) {
     uint t = deferred_edges->at(next);
     PointsToNode *ptt = ptnode_adr(t);
     uint e_cnt = ptt->edge_count();
     assert(e_cnt != 0, "should have at least phantom_object");
     for (uint e = 0; e < e_cnt; e++) {
       uint etgt = ptt->edge_target(e);
       if (visited->test_set(etgt))
         continue;
       PointsToNode::EdgeType et = ptt->edge_type(e);
       if (et == PointsToNode::PointsToEdge) {
         add_pointsto_edge(ni, etgt);
       } else if (et == PointsToNode::DeferredEdge) {
         deferred_edges->append(etgt);
       } else {
         assert(false,"invalid connection graph");
       }
     }
   }
   if (ptn->edge_count() == 0) {
     // No pointsto edges found after deferred edges are removed.
     // For example, in the next case where call is replaced
     // with uncommon trap and as result array's load references
     // itself through deferred edges:
     //
     // A a = b[i];
     // if (c!=null) a = c.foo();
     // b[i] = a;
     //
     // Assume the value was set outside this method and
     // add edge to phantom object.
     add_pointsto_edge(ni, _phantom_object);
   }
 }
 //  Add an edge to node given by "to_i" from any field of adr_i whose offset
 //  matches "offset"  A deferred edge is added if to_i is a LocalVar, and
 //  a pointsto edge is added if it is a JavaObject
 void ConnectionGraph::add_edge_from_fields(uint adr_i, uint to_i, int offs) {
   // No fields for NULL pointer.
   if (is_null_ptr(adr_i)) {
     return;
   }
   PointsToNode* an = ptnode_adr(adr_i);
   PointsToNode* to = ptnode_adr(to_i);
   bool deferred = (to->node_type() == PointsToNode::LocalVar);
   bool escaped  = (to_i == _phantom_object) && (offs == Type::OffsetTop);
   if (escaped) {
     // Values in fields escaped during call.
     assert(an->escape_state() >= PointsToNode::ArgEscape, "sanity");
     offs = Type::OffsetBot;
   }
   for (uint fe = 0; fe < an->edge_count(); fe++) {
     assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
     int fi = an->edge_target(fe);
     if (escaped) {
       set_escape_state(fi, PointsToNode::GlobalEscape);
     }
     PointsToNode* pf = ptnode_adr(fi);
     int po = pf->offset();
     if (po == offs || po == Type::OffsetBot || offs == Type::OffsetBot) {
       if (deferred)
         add_deferred_edge(fi, to_i);
       else
         add_pointsto_edge(fi, to_i);
     }
   }
 }
 // Add a deferred  edge from node given by "from_i" to any field of adr_i
 // whose offset matches "offset".
 void ConnectionGraph::add_deferred_edge_to_fields(uint from_i, uint adr_i, int offs) {
   // No fields for NULL pointer.
   if (is_null_ptr(adr_i)) {
     return;
   }
   if (adr_i == _phantom_object) {
     // Add only one edge for unknown object.
     add_pointsto_edge(from_i, _phantom_object);
     return;
   }
   PointsToNode* an = ptnode_adr(adr_i);
   bool is_alloc = an->_node->is_Allocate();
   for (uint fe = 0; fe < an->edge_count(); fe++) {
     assert(an->edge_type(fe) == PointsToNode::FieldEdge, "expecting a field edge");
     int fi = an->edge_target(fe);
     PointsToNode* pf = ptnode_adr(fi);
     int offset = pf->offset();
     if (!is_alloc) {
       // Assume the field was set outside this method if it is not Allocation
       add_pointsto_edge(fi, _phantom_object);
     }
     if (offset == offs || offset == Type::OffsetBot || offs == Type::OffsetBot) {
       add_deferred_edge(from_i, fi);
     }
   }
   // Some fields references (AddP) may still be missing
   // until Connection Graph construction is complete.
   // For example, loads from RAW pointers with offset 0
   // which don't have AddP.
   // A reference to phantom_object will be added if
   // a field reference is still missing after completing
   // Connection Graph (see remove_deferred()).
 }
 // Helper functions
 static Node* get_addp_base(Node *addp) {
   assert(addp->is_AddP(), "must be AddP");
   //
   // AddP cases for Base and Address inputs:
   // case #1. Direct object's field reference:
   //     Allocate
   //       |
   //     Proj #5 ( oop result )
   //       |
   //     CheckCastPP (cast to instance type)
   //      | |
   //     AddP  ( base == address )
   //
   // case #2. Indirect object's field reference:
   //      Phi
   //       |
   //     CastPP (cast to instance type)
   //      | |
   //     AddP  ( base == address )
   //
   // case #3. Raw object's field reference for Initialize node:
   //      Allocate
   //        |
   //      Proj #5 ( oop result )
   //  top   |
   //     \  |
   //     AddP  ( base == top )
   //
   // case #4. Array's element reference:
   //   {CheckCastPP | CastPP}
   //     |  | |
   //     |  AddP ( array's element offset )
   //     |  |
   //     AddP ( array's offset )
   //
   // case #5. Raw object's field reference for arraycopy stub call:
   //          The inline_native_clone() case when the arraycopy stub is called
   //          after the allocation before Initialize and CheckCastPP nodes.
   //      Allocate
   //        |
   //      Proj #5 ( oop result )
   //       | |
   //       AddP  ( base == address )
   //
   // case #6. Constant Pool, ThreadLocal, CastX2P or
   //          Raw object's field reference:
   //      {ConP, ThreadLocal, CastX2P, raw Load}
   //  top   |
   //     \  |
   //     AddP  ( base == top )
   //
   // case #7. Klass's field reference.
   //      LoadKlass
   //       | |
   //       AddP  ( base == address )
   //
   // case #8. narrow Klass's field reference.
   //      LoadNKlass
   //       |
   //      DecodeN
   //       | |
   //       AddP  ( base == address )
   //
   Node *base = addp->in(AddPNode::Base)->uncast();
   if (base->is_top()) { // The AddP case #3 and #6.
     base = addp->in(AddPNode::Address)->uncast();
     while (base->is_AddP()) {
       // Case #6 (unsafe access) may have several chained AddP nodes.
       assert(base->in(AddPNode::Base)->is_top(), "expected unsafe access address only");
       base = base->in(AddPNode::Address)->uncast();
     }
     assert(base->Opcode() == Op_ConP || base->Opcode() == Op_ThreadLocal ||
            base->Opcode() == Op_CastX2P || base->is_DecodeN() ||
            (base->is_Mem() && base->bottom_type() == TypeRawPtr::NOTNULL) ||
            (base->is_Proj() && base->in(0)->is_Allocate()), "sanity");
   }
   return base;
 }
 static Node* find_second_addp(Node* addp, Node* n) {
   assert(addp->is_AddP() && addp->outcnt() > 0, "Don't process dead nodes");
   Node* addp2 = addp->raw_out(0);
   if (addp->outcnt() == 1 && addp2->is_AddP() &&
       addp2->in(AddPNode::Base) == n &&
       addp2->in(AddPNode::Address) == addp) {
     assert(addp->in(AddPNode::Base) == n, "expecting the same base");
     //
     // Find array's offset to push it on worklist first and
     // as result process an array's element offset first (pushed second)
     // to avoid CastPP for the array's offset.
     // Otherwise the inserted CastPP (LocalVar) will point to what
     // the AddP (Field) points to. Which would be wrong since
     // the algorithm expects the CastPP has the same point as
     // as AddP's base CheckCastPP (LocalVar).
     //
     //    ArrayAllocation
     //     |
     //    CheckCastPP
     //     |
     //    memProj (from ArrayAllocation CheckCastPP)
     //     |  ||
     //     |  ||   Int (element index)
     //     |  ||    |   ConI (log(element size))
     //     |  ||    |   /
     //     |  ||   LShift
     //     |  ||  /
     //     |  AddP (array's element offset)
     //     |  |
     //     |  | ConI (array's offset: #12(32-bits) or #24(64-bits))
     //     | / /
     //     AddP (array's offset)
     //      |
     //     Load/Store (memory operation on array's element)
     //
     return addp2;
   }
   return NULL;
 }
 //
 // Adjust the type and inputs of an AddP which computes the
 // address of a field of an instance
 //
 bool ConnectionGraph::split_AddP(Node *addp, Node *base,  PhaseGVN  *igvn) {
   const TypeOopPtr *base_t = igvn->type(base)->isa_oopptr();
   assert(base_t != NULL && base_t->is_known_instance(), "expecting instance oopptr");
   const TypeOopPtr *t = igvn->type(addp)->isa_oopptr();
   if (t == NULL) {
     // We are computing a raw address for a store captured by an Initialize
     // compute an appropriate address type (cases #3 and #5).
     assert(igvn->type(addp) == TypeRawPtr::NOTNULL, "must be raw pointer");
     assert(addp->in(AddPNode::Address)->is_Proj(), "base of raw address must be result projection from allocation");
     intptr_t offs = (int)igvn->find_intptr_t_con(addp->in(AddPNode::Offset), Type::OffsetBot);
     assert(offs != Type::OffsetBot, "offset must be a constant");
     t = base_t->add_offset(offs)->is_oopptr();
   }
   int inst_id =  base_t->instance_id();
   assert(!t->is_known_instance() || t->instance_id() == inst_id,
                              "old type must be non-instance or match new type");
   // The type 't' could be subclass of 'base_t'.
   // As result t->offset() could be large then base_t's size and it will
   // cause the failure in add_offset() with narrow oops since TypeOopPtr()
   // constructor verifies correctness of the offset.
   //
   // It could happened on subclass's branch (from the type profiling
   // inlining) which was not eliminated during parsing since the exactness
   // of the allocation type was not propagated to the subclass type check.
   //
   // Or the type 't' could be not related to 'base_t' at all.
   // It could happened when CHA type is different from MDO type on a dead path
   // (for example, from instanceof check) which is not collapsed during parsing.
   //
   // Do nothing for such AddP node and don't process its users since
   // this code branch will go away.
   //
   if (!t->is_known_instance() &&
       !base_t->klass()->is_subtype_of(t->klass())) {
      return false; // bail out
   }
   const TypeOopPtr *tinst = base_t->add_offset(t->offset())->is_oopptr();
   // Do NOT remove the next line: ensure a new alias index is allocated
   // for the instance type. Note: C++ will not remove it since the call
   // has side effect.
   int alias_idx = _compile->get_alias_index(tinst);
   igvn->set_type(addp, tinst);
   // record the allocation in the node map
   assert(ptnode_adr(addp->_idx)->_node != NULL, "should be registered");
   set_map(addp->_idx, get_map(base->_idx));
   // Set addp's Base and Address to 'base'.
   Node *abase = addp->in(AddPNode::Base);
   Node *adr   = addp->in(AddPNode::Address);
   if (adr->is_Proj() && adr->in(0)->is_Allocate() &&
       adr->in(0)->_idx == (uint)inst_id) {
     // Skip AddP cases #3 and #5.
   } else {
     assert(!abase->is_top(), "sanity"); // AddP case #3
     if (abase != base) {
       igvn->hash_delete(addp);
       addp->set_req(AddPNode::Base, base);
       if (abase == adr) {
         addp->set_req(AddPNode::Address, base);
       } else {
         // AddP case #4 (adr is array's element offset AddP node)
 #ifdef ASSERT
         const TypeOopPtr *atype = igvn->type(adr)->isa_oopptr();
         assert(adr->is_AddP() && atype != NULL &&
                atype->instance_id() == inst_id, "array's element offset should be processed first");
 #endif
       }
       igvn->hash_insert(addp);
     }
   }
   // Put on IGVN worklist since at least addp's type was changed above.
   record_for_optimizer(addp);
   return true;
 }
 //
 // Create a new version of orig_phi if necessary. Returns either the newly
 // created phi or an existing phi.  Sets create_new to indicate whether a new
 // phi was created.  Cache the last newly created phi in the node map.
 //
 PhiNode *ConnectionGraph::create_split_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn, bool &new_created) {
   Compile *C = _compile;
   new_created = false;
   int phi_alias_idx = C->get_alias_index(orig_phi->adr_type());
   // nothing to do if orig_phi is bottom memory or matches alias_idx
   if (phi_alias_idx == alias_idx) {
     return orig_phi;
   }
   // Have we recently created a Phi for this alias index?
   PhiNode *result = get_map_phi(orig_phi->_idx);
   if (result != NULL && C->get_alias_index(result->adr_type()) == alias_idx) {
     return result;
   }
   // Previous check may fail when the same wide memory Phi was split into Phis
   // for different memory slices. Search all Phis for this region.
   if (result != NULL) {
     Node* region = orig_phi->in(0);
     for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
       Node* phi = region->fast_out(i);
       if (phi->is_Phi() &&
           C->get_alias_index(phi->as_Phi()->adr_type()) == alias_idx) {
         assert(phi->_idx >= nodes_size(), "only new Phi per instance memory slice");
         return phi->as_Phi();
       }
     }
   }
   if ((int)C->unique() + 2*NodeLimitFudgeFactor > MaxNodeLimit) {
     if (C->do_escape_analysis() == true && !C->failing()) {
       // Retry compilation without escape analysis.
       // If this is the first failure, the sentinel string will "stick"
       // to the Compile object, and the C2Compiler will see it and retry.
       C->record_failure(C2Compiler::retry_no_escape_analysis());
     }
     return NULL;
   }
   orig_phi_worklist.append_if_missing(orig_phi);
   const TypePtr *atype = C->get_adr_type(alias_idx);
   result = PhiNode::make(orig_phi->in(0), NULL, Type::MEMORY, atype);
   C->copy_node_notes_to(result, orig_phi);
   igvn->set_type(result, result->bottom_type());
   record_for_optimizer(result);
   debug_only(Node* pn = ptnode_adr(orig_phi->_idx)->_node;)
   assert(pn == NULL || pn == orig_phi, "wrong node");
   set_map(orig_phi->_idx, result);
   ptnode_adr(orig_phi->_idx)->_node = orig_phi;
   new_created = true;
   return result;
 }
 //
 // Return a new version of Memory Phi "orig_phi" with the inputs having the
 // specified alias index.
 //
 PhiNode *ConnectionGraph::split_memory_phi(PhiNode *orig_phi, int alias_idx, GrowableArray<PhiNode *>  &orig_phi_worklist, PhaseGVN  *igvn) {
   assert(alias_idx != Compile::AliasIdxBot, "can't split out bottom memory");
   Compile *C = _compile;
   bool new_phi_created;
   PhiNode *result = create_split_phi(orig_phi, alias_idx, orig_phi_worklist, igvn, new_phi_created);
   if (!new_phi_created) {
     return result;
   }
   GrowableArray<PhiNode *>  phi_list;
   GrowableArray<uint>  cur_input;
   PhiNode *phi = orig_phi;
   uint idx = 1;
   bool finished = false;
   while(!finished) {
     while (idx < phi->req()) {
       Node *mem = find_inst_mem(phi->in(idx), alias_idx, orig_phi_worklist, igvn);
       if (mem != NULL && mem->is_Phi()) {
         PhiNode *newphi = create_split_phi(mem->as_Phi(), alias_idx, orig_phi_worklist, igvn, new_phi_created);
         if (new_phi_created) {
           // found an phi for which we created a new split, push current one on worklist and begin
           // processing new one
           phi_list.push(phi);
           cur_input.push(idx);
           phi = mem->as_Phi();
           result = newphi;
           idx = 1;
           continue;
         } else {
           mem = newphi;
         }
       }
       if (C->failing()) {
         return NULL;
       }
       result->set_req(idx++, mem);
     }
 #ifdef ASSERT
     // verify that the new Phi has an input for each input of the original
     assert( phi->req() == result->req(), "must have same number of inputs.");
     assert( result->in(0) != NULL && result->in(0) == phi->in(0), "regions must match");
 #endif
     // Check if all new phi's inputs have specified alias index.
     // Otherwise use old phi.
     for (uint i = 1; i < phi->req(); i++) {
       Node* in = result->in(i);
       assert((phi->in(i) == NULL) == (in == NULL), "inputs must correspond.");
     }
     // we have finished processing a Phi, see if there are any more to do
     finished = (phi_list.length() == 0 );
     if (!finished) {
       phi = phi_list.pop();
       idx = cur_input.pop();
       PhiNode *prev_result = get_map_phi(phi->_idx);
       prev_result->set_req(idx++, result);
       result = prev_result;
     }
   }
   return result;
 }
 //
 // The next methods are derived from methods in MemNode.
 //
 static Node *step_through_mergemem(MergeMemNode *mmem, int alias_idx, const TypeOopPtr *toop) {
   Node *mem = mmem;
   // TypeOopPtr::NOTNULL+any is an OOP with unknown offset - generally
   // means an array I have not precisely typed yet.  Do not do any
   // alias stuff with it any time soon.
   if( toop->base() != Type::AnyPtr &&
       !(toop->klass() != NULL &&
         toop->klass()->is_java_lang_Object() &&
         toop->offset() == Type::OffsetBot) ) {
     mem = mmem->memory_at(alias_idx);
     // Update input if it is progress over what we have now
   }
   return mem;
 }
 //
 // Move memory users to their memory slices.
 //
 void ConnectionGraph::move_inst_mem(Node* n, GrowableArray<PhiNode *>  &orig_phis, PhaseGVN *igvn) {
   Compile* C = _compile;
   const TypePtr* tp = igvn->type(n->in(MemNode::Address))->isa_ptr();
   assert(tp != NULL, "ptr type");
   int alias_idx = C->get_alias_index(tp);
   int general_idx = C->get_general_index(alias_idx);
   // Move users first
   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
     Node* use = n->fast_out(i);
     if (use->is_MergeMem()) {
       MergeMemNode* mmem = use->as_MergeMem();
       assert(n == mmem->memory_at(alias_idx), "should be on instance memory slice");
       if (n != mmem->memory_at(general_idx) || alias_idx == general_idx) {
         continue; // Nothing to do
       }
       // Replace previous general reference to mem node.
       uint orig_uniq = C->unique();
       Node* m = find_inst_mem(n, general_idx, orig_phis, igvn);
       assert(orig_uniq == C->unique(), "no new nodes");
       mmem->set_memory_at(general_idx, m);
       --imax;
       --i;
     } else if (use->is_MemBar()) {
       assert(!use->is_Initialize(), "initializing stores should not be moved");
       if (use->req() > MemBarNode::Precedent &&
           use->in(MemBarNode::Precedent) == n) {
         // Don't move related membars.
         record_for_optimizer(use);
         continue;
       }
       tp = use->as_MemBar()->adr_type()->isa_ptr();
       if (tp != NULL && C->get_alias_index(tp) == alias_idx ||
           alias_idx == general_idx) {
         continue; // Nothing to do
       }
       // Move to general memory slice.
       uint orig_uniq = C->unique();
       Node* m = find_inst_mem(n, general_idx, orig_phis, igvn);
       assert(orig_uniq == C->unique(), "no new nodes");
       igvn->hash_delete(use);
       imax -= use->replace_edge(n, m);
       igvn->hash_insert(use);
       record_for_optimizer(use);
       --i;
 #ifdef ASSERT
     } else if (use->is_Mem()) {
       if (use->Opcode() == Op_StoreCM && use->in(MemNode::OopStore) == n) {
         // Don't move related cardmark.
         continue;
       }
       // Memory nodes should have new memory input.
       tp = igvn->type(use->in(MemNode::Address))->isa_ptr();
       assert(tp != NULL, "ptr type");
       int idx = C->get_alias_index(tp);
       assert(get_map(use->_idx) != NULL || idx == alias_idx,
              "Following memory nodes should have new memory input or be on the same memory slice");
     } else if (use->is_Phi()) {
       // Phi nodes should be split and moved already.
       tp = use->as_Phi()->adr_type()->isa_ptr();
       assert(tp != NULL, "ptr type");
       int idx = C->get_alias_index(tp);
       assert(idx == alias_idx, "Following Phi nodes should be on the same memory slice");
     } else {
       use->dump();
       assert(false, "should not be here");
 #endif
     }
   }
 }
 //
 // Search memory chain of "mem" to find a MemNode whose address
 // is the specified alias index.
 //
 Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArray<PhiNode *>  &orig_phis, PhaseGVN *phase) {
   if (orig_mem == NULL)
     return orig_mem;
   Compile* C = phase->C;
   const TypeOopPtr *toop = C->get_adr_type(alias_idx)->isa_oopptr();
   bool is_instance = (toop != NULL) && toop->is_known_instance();
   Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
   Node *prev = NULL;
   Node *result = orig_mem;
   while (prev != result) {
     prev = result;
     if (result == start_mem)
       break;  // hit one of our sentinels
     if (result->is_Mem()) {
       const Type *at = phase->type(result->in(MemNode::Address));
       if (at == Type::TOP)
         break; // Dead
       assert (at->isa_ptr() != NULL, "pointer type required.");
       int idx = C->get_alias_index(at->is_ptr());
       if (idx == alias_idx)
         break; // Found
       if (!is_instance && (at->isa_oopptr() == NULL ||
                            !at->is_oopptr()->is_known_instance())) {
         break; // Do not skip store to general memory slice.
       }
       result = result->in(MemNode::Memory);
     }
     if (!is_instance)
       continue;  // don't search further for non-instance types
     // skip over a call which does not affect this memory slice
     if (result->is_Proj() && result->as_Proj()->_con == TypeFunc::Memory) {
       Node *proj_in = result->in(0);
       if (proj_in->is_Allocate() && proj_in->_idx == (uint)toop->instance_id()) {
         break;  // hit one of our sentinels
       } else if (proj_in->is_Call()) {
         CallNode *call = proj_in->as_Call();
         if (!call->may_modify(toop, phase)) {
           result = call->in(TypeFunc::Memory);
         }
       } else if (proj_in->is_Initialize()) {
         AllocateNode* alloc = proj_in->as_Initialize()->allocation();
         // Stop if this is the initialization for the object instance which
         // which contains this memory slice, otherwise skip over it.
         if (alloc == NULL || alloc->_idx != (uint)toop->instance_id()) {
           result = proj_in->in(TypeFunc::Memory);
         }
       } else if (proj_in->is_MemBar()) {
         result = proj_in->in(TypeFunc::Memory);
       }
     } else if (result->is_MergeMem()) {
       MergeMemNode *mmem = result->as_MergeMem();
       result = step_through_mergemem(mmem, alias_idx, toop);
       if (result == mmem->base_memory()) {
         // Didn't find instance memory, search through general slice recursively.
         result = mmem->memory_at(C->get_general_index(alias_idx));
         result = find_inst_mem(result, alias_idx, orig_phis, phase);
         if (C->failing()) {
           return NULL;
         }
         mmem->set_memory_at(alias_idx, result);
       }
     } else if (result->is_Phi() &&
                C->get_alias_index(result->as_Phi()->adr_type()) != alias_idx) {
       Node *un = result->as_Phi()->unique_input(phase);
       if (un != NULL) {
         orig_phis.append_if_missing(result->as_Phi());
         result = un;
       } else {
         break;
       }
     } else if (result->is_ClearArray()) {
       if (!ClearArrayNode::step_through(&result, (uint)toop->instance_id(), phase)) {
         // Can not bypass initialization of the instance
         // we are looking for.
         break;
       }
       // Otherwise skip it (the call updated 'result' value).
     } else if (result->Opcode() == Op_SCMemProj) {
       assert(result->in(0)->is_LoadStore(), "sanity");
       const Type *at = phase->type(result->in(0)->in(MemNode::Address));
       if (at != Type::TOP) {
         assert (at->isa_ptr() != NULL, "pointer type required.");
         int idx = C->get_alias_index(at->is_ptr());
         assert(idx != alias_idx, "Object is not scalar replaceable if a LoadStore node access its field");
         break;
       }
       result = result->in(0)->in(MemNode::Memory);
     }
   }
   if (result->is_Phi()) {
     PhiNode *mphi = result->as_Phi();
     assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
     const TypePtr *t = mphi->adr_type();
     if (!is_instance) {
       // Push all non-instance Phis on the orig_phis worklist to update inputs
       // during Phase 4 if needed.
       orig_phis.append_if_missing(mphi);
     } else if (C->get_alias_index(t) != alias_idx) {
       // Create a new Phi with the specified alias index type.
       result = split_memory_phi(mphi, alias_idx, orig_phis, phase);
     }
   }
   // the result is either MemNode, PhiNode, InitializeNode.
   return result;
 }
 //
 //  Convert the types of unescaped object to instance types where possible,
 //  propagate the new type information through the graph, and update memory
 //  edges and MergeMem inputs to reflect the new type.
 //
 //  We start with allocations (and calls which may be allocations)  on alloc_worklist.
 //  The processing is done in 4 phases:
 //
 //  Phase 1:  Process possible allocations from alloc_worklist.  Create instance
 //            types for the CheckCastPP for allocations where possible.
 //            Propagate the the new types through users as follows:
 //               casts and Phi:  push users on alloc_worklist
 //               AddP:  cast Base and Address inputs to the instance type
 //                      push any AddP users on alloc_worklist and push any memnode
 //                      users onto memnode_worklist.
 //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
 //            search the Memory chain for a store with the appropriate type
 //            address type.  If a Phi is found, create a new version with
 //            the appropriate memory slices from each of the Phi inputs.
 //            For stores, process the users as follows:
 //               MemNode:  push on memnode_worklist
 //               MergeMem: push on mergemem_worklist
 //  Phase 3:  Process MergeMem nodes from mergemem_worklist.  Walk each memory slice
 //            moving the first node encountered of each  instance type to the
 //            the input corresponding to its alias index.
 //            appropriate memory slice.
 //  Phase 4:  Update the inputs of non-instance memory Phis and the Memory input of memnodes.
 //
 // In the following example, the CheckCastPP nodes are the cast of allocation
 // results and the allocation of node 29 is unescaped and eligible to be an
 // instance type.
 //
 // We start with:
 //
 //     7 Parm #memory
 //    10  ConI  "12"
 //    19  CheckCastPP   "Foo"
 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
 //    29  CheckCastPP   "Foo"
 //    30  AddP  _ 29 29 10  Foo+12  alias_index=4
 //
 //    40  StoreP  25   7  20   ... alias_index=4
 //    50  StoreP  35  40  30   ... alias_index=4
 //    60  StoreP  45  50  20   ... alias_index=4
 //    70  LoadP    _  60  30   ... alias_index=4
 //    80  Phi     75  50  60   Memory alias_index=4
 //    90  LoadP    _  80  30   ... alias_index=4
 //   100  LoadP    _  80  20   ... alias_index=4
 //
 //
 // Phase 1 creates an instance type for node 29 assigning it an instance id of 24
 // and creating a new alias index for node 30.  This gives:
 //
 //     7 Parm #memory
 //    10  ConI  "12"
 //    19  CheckCastPP   "Foo"
 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
 //    29  CheckCastPP   "Foo"  iid=24
 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
 //
 //    40  StoreP  25   7  20   ... alias_index=4
 //    50  StoreP  35  40  30   ... alias_index=6
 //    60  StoreP  45  50  20   ... alias_index=4
 //    70  LoadP    _  60  30   ... alias_index=6
 //    80  Phi     75  50  60   Memory alias_index=4
 //    90  LoadP    _  80  30   ... alias_index=6
 //   100  LoadP    _  80  20   ... alias_index=4
 //
 // In phase 2, new memory inputs are computed for the loads and stores,
 // And a new version of the phi is created.  In phase 4, the inputs to
 // node 80 are updated and then the memory nodes are updated with the
 // values computed in phase 2.  This results in:
 //
 //     7 Parm #memory
 //    10  ConI  "12"
 //    19  CheckCastPP   "Foo"
 //    20  AddP  _ 19 19 10  Foo+12  alias_index=4
 //    29  CheckCastPP   "Foo"  iid=24
 //    30  AddP  _ 29 29 10  Foo+12  alias_index=6  iid=24
 //
 //    40  StoreP  25  7   20   ... alias_index=4
 //    50  StoreP  35  7   30   ... alias_index=6
 //    60  StoreP  45  40  20   ... alias_index=4
 //    70  LoadP    _  50  30   ... alias_index=6
 //    80  Phi     75  40  60   Memory alias_index=4
 //   120  Phi     75  50  50   Memory alias_index=6
 //    90  LoadP    _ 120  30   ... alias_index=6
 //   100  LoadP    _  80  20   ... alias_index=4
 //
 void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist) {
   GrowableArray<Node *>  memnode_worklist;
   GrowableArray<PhiNode *>  orig_phis;
   PhaseIterGVN  *igvn = _igvn;
   uint new_index_start = (uint) _compile->num_alias_types();
   Arena* arena = Thread::current()->resource_area();
   VectorSet visited(arena);
   //  Phase 1:  Process possible allocations from alloc_worklist.
   //  Create instance types for the CheckCastPP for allocations where possible.
   //
   // (Note: don't forget to change the order of the second AddP node on
   //  the alloc_worklist if the order of the worklist processing is changed,
   //  see the comment in find_second_addp().)
   //
   while (alloc_worklist.length() != 0) {
     Node *n = alloc_worklist.pop();
     uint ni = n->_idx;
     const TypeOopPtr* tinst = NULL;
     if (n->is_Call()) {
       CallNode *alloc = n->as_Call();
       // copy escape information to call node
       PointsToNode* ptn = ptnode_adr(alloc->_idx);
       PointsToNode::EscapeState es = escape_state(alloc);
       // We have an allocation or call which returns a Java object,
       // see if it is unescaped.
       if (es != PointsToNode::NoEscape || !ptn->scalar_replaceable())
         continue;
       // Find CheckCastPP for the allocate or for the return value of a call
       n = alloc->result_cast();
       if (n == NULL) {            // No uses except Initialize node
         if (alloc->is_Allocate()) {
           // Set the scalar_replaceable flag for allocation
           // so it could be eliminated if it has no uses.
           alloc->as_Allocate()->_is_scalar_replaceable = true;
         }
         continue;
       }
       if (!n->is_CheckCastPP()) { // not unique CheckCastPP.
         assert(!alloc->is_Allocate(), "allocation should have unique type");
         continue;
       }
       // The inline code for Object.clone() casts the allocation result to
       // java.lang.Object and then to the actual type of the allocated
       // object. Detect this case and use the second cast.
       // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
       // the allocation result is cast to java.lang.Object and then
       // to the actual Array type.
       if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
           && (alloc->is_AllocateArray() ||
               igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
         Node *cast2 = NULL;
         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
           Node *use = n->fast_out(i);
           if (use->is_CheckCastPP()) {
             cast2 = use;
             break;
           }
         }
         if (cast2 != NULL) {
           n = cast2;
         } else {
           // Non-scalar replaceable if the allocation type is unknown statically
           // (reflection allocation), the object can't be restored during
           // deoptimization without precise type.
           continue;
         }
       }
       if (alloc->is_Allocate()) {
         // Set the scalar_replaceable flag for allocation
         // so it could be eliminated.
         alloc->as_Allocate()->_is_scalar_replaceable = true;
       }
       set_escape_state(n->_idx, es); // CheckCastPP escape state
       // in order for an object to be scalar-replaceable, it must be:
       //   - a direct allocation (not a call returning an object)
       //   - non-escaping
       //   - eligible to be a unique type
       //   - not determined to be ineligible by escape analysis
       assert(ptnode_adr(alloc->_idx)->_node != NULL &&
              ptnode_adr(n->_idx)->_node != NULL, "should be registered");
       set_map(alloc->_idx, n);
       set_map(n->_idx, alloc);
       const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
       if (t == NULL)
         continue;  // not a TypeOopPtr
       tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni);
       igvn->hash_delete(n);
       igvn->set_type(n,  tinst);
       n->raise_bottom_type(tinst);
       igvn->hash_insert(n);
       record_for_optimizer(n);
       if (alloc->is_Allocate() && (t->isa_instptr() || t->isa_aryptr())) {
         // First, put on the worklist all Field edges from Connection Graph
         // which is more accurate then putting immediate users from Ideal Graph.
         for (uint e = 0; e < ptn->edge_count(); e++) {
           Node *use = ptnode_adr(ptn->edge_target(e))->_node;
           assert(ptn->edge_type(e) == PointsToNode::FieldEdge && use->is_AddP(),
                  "only AddP nodes are Field edges in CG");
           if (use->outcnt() > 0) { // Don't process dead nodes
             Node* addp2 = find_second_addp(use, use->in(AddPNode::Base));
             if (addp2 != NULL) {
               assert(alloc->is_AllocateArray(),"array allocation was expected");
               alloc_worklist.append_if_missing(addp2);
             }
             alloc_worklist.append_if_missing(use);
           }
         }
         // An allocation may have an Initialize which has raw stores. Scan
         // the users of the raw allocation result and push AddP users
         // on alloc_worklist.
         Node *raw_result = alloc->proj_out(TypeFunc::Parms);
         assert (raw_result != NULL, "must have an allocation result");
         for (DUIterator_Fast imax, i = raw_result->fast_outs(imax); i < imax; i++) {
           Node *use = raw_result->fast_out(i);
           if (use->is_AddP() && use->outcnt() > 0) { // Don't process dead nodes
             Node* addp2 = find_second_addp(use, raw_result);
             if (addp2 != NULL) {
               assert(alloc->is_AllocateArray(),"array allocation was expected");
               alloc_worklist.append_if_missing(addp2);
             }
             alloc_worklist.append_if_missing(use);
           } else if (use->is_MemBar()) {
             memnode_worklist.append_if_missing(use);
           }
         }
       }
     } else if (n->is_AddP()) {
       VectorSet* ptset = PointsTo(get_addp_base(n));
       assert(ptset->Size() == 1, "AddP address is unique");
       uint elem = ptset->getelem(); // Allocation node's index
       if (elem == _phantom_object) {
         assert(false, "escaped allocation");
         continue; // Assume the value was set outside this method.
       }
       Node *base = get_map(elem);  // CheckCastPP node
       if (!split_AddP(n, base, igvn)) continue; // wrong type from dead path
       tinst = igvn->type(base)->isa_oopptr();
     } else if (n->is_Phi() ||
                n->is_CheckCastPP() ||
                n->is_EncodeP() ||
                n->is_DecodeN() ||
                (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
       if (visited.test_set(n->_idx)) {
         assert(n->is_Phi(), "loops only through Phi's");
         continue;  // already processed
       }
       VectorSet* ptset = PointsTo(n);
       if (ptset->Size() == 1) {
         uint elem = ptset->getelem(); // Allocation node's index
         if (elem == _phantom_object) {
           assert(false, "escaped allocation");
           continue; // Assume the value was set outside this method.
         }
         Node *val = get_map(elem);   // CheckCastPP node
         TypeNode *tn = n->as_Type();
         tinst = igvn->type(val)->isa_oopptr();
         assert(tinst != NULL && tinst->is_known_instance() &&
                (uint)tinst->instance_id() == elem , "instance type expected.");
         const Type *tn_type = igvn->type(tn);
         const TypeOopPtr *tn_t;
         if (tn_type->isa_narrowoop()) {
           tn_t = tn_type->make_ptr()->isa_oopptr();
         } else {
           tn_t = tn_type->isa_oopptr();
         }
         if (tn_t != NULL && tinst->klass()->is_subtype_of(tn_t->klass())) {
           if (tn_type->isa_narrowoop()) {
             tn_type = tinst->make_narrowoop();
           } else {
             tn_type = tinst;
           }
           igvn->hash_delete(tn);
           igvn->set_type(tn, tn_type);
           tn->set_type(tn_type);
           igvn->hash_insert(tn);
           record_for_optimizer(n);
         } else {
           assert(tn_type == TypePtr::NULL_PTR ||
                  tn_t != NULL && !tinst->klass()->is_subtype_of(tn_t->klass()),
                  "unexpected type");
           continue; // Skip dead path with different type
         }
       }
     } else {
       debug_only(n->dump();)
       assert(false, "EA: unexpected node");
       continue;
     }
     // push allocation's users on appropriate worklist
     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
       Node *use = n->fast_out(i);
       if(use->is_Mem() && use->in(MemNode::Address) == n) {
         // Load/store to instance's field
         memnode_worklist.append_if_missing(use);
       } else if (use->is_MemBar()) {
         memnode_worklist.append_if_missing(use);
       } else if (use->is_AddP() && use->outcnt() > 0) { // No dead nodes
         Node* addp2 = find_second_addp(use, n);
         if (addp2 != NULL) {
           alloc_worklist.append_if_missing(addp2);
         }
         alloc_worklist.append_if_missing(use);
       } else if (use->is_Phi() ||
                  use->is_CheckCastPP() ||
                  use->is_EncodeP() ||
                  use->is_DecodeN() ||
                  (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
         alloc_worklist.append_if_missing(use);
 #ifdef ASSERT
       } else if (use->is_Mem()) {
         assert(use->in(MemNode::Address) != n, "EA: missing allocation reference path");
       } else if (use->is_MergeMem()) {
         assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
       } else if (use->is_SafePoint()) {
         // Look for MergeMem nodes for calls which reference unique allocation
         // (through CheckCastPP nodes) even for debug info.
         Node* m = use->in(TypeFunc::Memory);
         if (m->is_MergeMem()) {
           assert(_mergemem_worklist.contains(m->as_MergeMem()), "EA: missing MergeMem node in the worklist");
         }
       } else {
         uint op = use->Opcode();
         if (!(op == Op_CmpP || op == Op_Conv2B ||
               op == Op_CastP2X || op == Op_StoreCM ||
               op == Op_FastLock || op == Op_AryEq || op == Op_StrComp ||
               op == Op_StrEquals || op == Op_StrIndexOf)) {
           n->dump();
           use->dump();
           assert(false, "EA: missing allocation reference path");
         }
 #endif
       }
     }
   }
   // New alias types were created in split_AddP().
   uint new_index_end = (uint) _compile->num_alias_types();
   //  Phase 2:  Process MemNode's from memnode_worklist. compute new address type and
   //            compute new values for Memory inputs  (the Memory inputs are not
   //            actually updated until phase 4.)
   if (memnode_worklist.length() == 0)
     return;  // nothing to do
   while (memnode_worklist.length() != 0) {
     Node *n = memnode_worklist.pop();
     if (visited.test_set(n->_idx))
       continue;
     if (n->is_Phi() || n->is_ClearArray()) {
       // we don't need to do anything, but the users must be pushed
     } else if (n->is_MemBar()) { // Initialize, MemBar nodes
       // we don't need to do anything, but the users must be pushed
       n = n->as_MemBar()->proj_out(TypeFunc::Memory);
       if (n == NULL)
         continue;
     } else {
       assert(n->is_Mem(), "memory node required.");
       Node *addr = n->in(MemNode::Address);
       const Type *addr_t = igvn->type(addr);
       if (addr_t == Type::TOP)
         continue;
       assert (addr_t->isa_ptr() != NULL, "pointer type required.");
       int alias_idx = _compile->get_alias_index(addr_t->is_ptr());
       assert ((uint)alias_idx < new_index_end, "wrong alias index");
       Node *mem = find_inst_mem(n->in(MemNode::Memory), alias_idx, orig_phis, igvn);
       if (_compile->failing()) {
         return;
       }
       if (mem != n->in(MemNode::Memory)) {
         // We delay the memory edge update since we need old one in
         // MergeMem code below when instances memory slices are separated.
         debug_only(Node* pn = ptnode_adr(n->_idx)->_node;)
         assert(pn == NULL || pn == n, "wrong node");
         set_map(n->_idx, mem);
         ptnode_adr(n->_idx)->_node = n;
       }
       if (n->is_Load()) {
         continue;  // don't push users
       } else if (n->is_LoadStore()) {
         // get the memory projection
         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
           Node *use = n->fast_out(i);
           if (use->Opcode() == Op_SCMemProj) {
             n = use;
             break;
           }
         }
         assert(n->Opcode() == Op_SCMemProj, "memory projection required");
       }
     }
     // push user on appropriate worklist
     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
       Node *use = n->fast_out(i);
       if (use->is_Phi() || use->is_ClearArray()) {
         memnode_worklist.append_if_missing(use);
       } else if(use->is_Mem() && use->in(MemNode::Memory) == n) {
         if (use->Opcode() == Op_StoreCM) // Ignore cardmark stores
           continue;
         memnode_worklist.append_if_missing(use);
       } else if (use->is_MemBar()) {
         memnode_worklist.append_if_missing(use);
 #ifdef ASSERT
       } else if(use->is_Mem()) {
         assert(use->in(MemNode::Memory) != n, "EA: missing memory path");
       } else if (use->is_MergeMem()) {
         assert(_mergemem_worklist.contains(use->as_MergeMem()), "EA: missing MergeMem node in the worklist");
       } else {
         uint op = use->Opcode();
         if (!(op == Op_StoreCM ||
               (op == Op_CallLeaf && use->as_CallLeaf()->_name != NULL &&
                strcmp(use->as_CallLeaf()->_name, "g1_wb_pre") == 0) ||
               op == Op_AryEq || op == Op_StrComp ||
               op == Op_StrEquals || op == Op_StrIndexOf)) {
           n->dump();
           use->dump();
           assert(false, "EA: missing memory path");
         }
 #endif
       }
     }
   }
   //  Phase 3:  Process MergeMem nodes from mergemem_worklist.
   //            Walk each memory slice moving the first node encountered of each
   //            instance type to the the input corresponding to its alias index.
   uint length = _mergemem_worklist.length();
   for( uint next = 0; next < length; ++next ) {
     MergeMemNode* nmm = _mergemem_worklist.at(next);
     assert(!visited.test_set(nmm->_idx), "should not be visited before");
     // Note: we don't want to use MergeMemStream here because we only want to
     // scan inputs which exist at the start, not ones we add during processing.
     // Note 2: MergeMem may already contains instance memory slices added
     // during find_inst_mem() call when memory nodes were processed above.
     igvn->hash_delete(nmm);
     uint nslices = nmm->req();
     for (uint i = Compile::AliasIdxRaw+1; i < nslices; i++) {
       Node* mem = nmm->in(i);
       Node* cur = NULL;
       if (mem == NULL || mem->is_top())
         continue;
       // First, update mergemem by moving memory nodes to corresponding slices
       // if their type became more precise since this mergemem was created.
       while (mem->is_Mem()) {
         const Type *at = igvn->type(mem->in(MemNode::Address));
         if (at != Type::TOP) {
           assert (at->isa_ptr() != NULL, "pointer type required.");
           uint idx = (uint)_compile->get_alias_index(at->is_ptr());
           if (idx == i) {
             if (cur == NULL)
               cur = mem;
           } else {
             if (idx >= nmm->req() || nmm->is_empty_memory(nmm->in(idx))) {
               nmm->set_memory_at(idx, mem);
             }
           }
         }
         mem = mem->in(MemNode::Memory);
       }
       nmm->set_memory_at(i, (cur != NULL) ? cur : mem);
       // Find any instance of the current type if we haven't encountered
       // already a memory slice of the instance along the memory chain.
       for (uint ni = new_index_start; ni < new_index_end; ni++) {
         if((uint)_compile->get_general_index(ni) == i) {
           Node *m = (ni >= nmm->req()) ? nmm->empty_memory() : nmm->in(ni);
           if (nmm->is_empty_memory(m)) {
             Node* result = find_inst_mem(mem, ni, orig_phis, igvn);
             if (_compile->failing()) {
               return;
             }
             nmm->set_memory_at(ni, result);
           }
         }
       }
     }
     // Find the rest of instances values
     for (uint ni = new_index_start; ni < new_index_end; ni++) {
       const TypeOopPtr *tinst = _compile->get_adr_type(ni)->isa_oopptr();
       Node* result = step_through_mergemem(nmm, ni, tinst);
       if (result == nmm->base_memory()) {
         // Didn't find instance memory, search through general slice recursively.
         result = nmm->memory_at(_compile->get_general_index(ni));
         result = find_inst_mem(result, ni, orig_phis, igvn);
         if (_compile->failing()) {
           return;
         }
         nmm->set_memory_at(ni, result);
       }
     }
     igvn->hash_insert(nmm);
     record_for_optimizer(nmm);
   }
   //  Phase 4:  Update the inputs of non-instance memory Phis and
   //            the Memory input of memnodes
   // First update the inputs of any non-instance Phi's from
   // which we split out an instance Phi.  Note we don't have
   // to recursively process Phi's encounted on the input memory
   // chains as is done in split_memory_phi() since they  will
   // also be processed here.
   for (int j = 0; j < orig_phis.length(); j++) {
     PhiNode *phi = orig_phis.at(j);
     int alias_idx = _compile->get_alias_index(phi->adr_type());
     igvn->hash_delete(phi);
     for (uint i = 1; i < phi->req(); i++) {
       Node *mem = phi->in(i);
       Node *new_mem = find_inst_mem(mem, alias_idx, orig_phis, igvn);
       if (_compile->failing()) {
         return;
       }
       if (mem != new_mem) {
         phi->set_req(i, new_mem);
       }
     }
     igvn->hash_insert(phi);
     record_for_optimizer(phi);
   }
   // Update the memory inputs of MemNodes with the value we computed
   // in Phase 2 and move stores memory users to corresponding memory slices.
   // Disable memory split verification code until the fix for 6984348.
   // Currently it produces false negative results since it does not cover all cases.
 #if 0 // ifdef ASSERT
   visited.Reset();
   Node_Stack old_mems(arena, _compile->unique() >> 2);
 #endif
   for (uint i = 0; i < nodes_size(); i++) {
     Node *nmem = get_map(i);
     if (nmem != NULL) {
       Node *n = ptnode_adr(i)->_node;
       assert(n != NULL, "sanity");
       if (n->is_Mem()) {
 #if 0 // ifdef ASSERT
         Node* old_mem = n->in(MemNode::Memory);
         if (!visited.test_set(old_mem->_idx)) {
           old_mems.push(old_mem, old_mem->outcnt());
         }
 #endif
         assert(n->in(MemNode::Memory) != nmem, "sanity");
         if (!n->is_Load()) {
           // Move memory users of a store first.
           move_inst_mem(n, orig_phis, igvn);
         }
         // Now update memory input
         igvn->hash_delete(n);
         n->set_req(MemNode::Memory, nmem);
         igvn->hash_insert(n);
         record_for_optimizer(n);
       } else {
         assert(n->is_Allocate() || n->is_CheckCastPP() ||
                n->is_AddP() || n->is_Phi(), "unknown node used for set_map()");
       }
     }
   }
 #if 0 // ifdef ASSERT
   // Verify that memory was split correctly
   while (old_mems.is_nonempty()) {
     Node* old_mem = old_mems.node();
     uint  old_cnt = old_mems.index();
     old_mems.pop();
     assert(old_cnt == old_mem->outcnt(), "old mem could be lost");
   }
 #endif
 }
 bool ConnectionGraph::has_candidates(Compile *C) {
   // EA brings benefits only when the code has allocations and/or locks which
   // are represented by ideal Macro nodes.
   int cnt = C->macro_count();
   for( int i=0; i < cnt; i++ ) {
     Node *n = C->macro_node(i);
     if ( n->is_Allocate() )
       return true;
     if( n->is_Lock() ) {
       Node* obj = n->as_Lock()->obj_node()->uncast();
       if( !(obj->is_Parm() || obj->is_Con()) )
         return true;
     }
   }
   return false;
 }
 void ConnectionGraph::do_analysis(Compile *C, PhaseIterGVN *igvn) {
   // Add ConP#NULL and ConN#NULL nodes before ConnectionGraph construction
   // to create space for them in ConnectionGraph::_nodes[].
   Node* oop_null = igvn->zerocon(T_OBJECT);
   Node* noop_null = igvn->zerocon(T_NARROWOOP);
   ConnectionGraph* congraph = new(C->comp_arena()) ConnectionGraph(C, igvn);
   // Perform escape analysis
   if (congraph->compute_escape()) {
     // There are non escaping objects.
     C->set_congraph(congraph);
   }
   // Cleanup.
   if (oop_null->outcnt() == 0)
     igvn->hash_delete(oop_null);
   if (noop_null->outcnt() == 0)
     igvn->hash_delete(noop_null);
 }
 bool ConnectionGraph::compute_escape() {
   Compile* C = _compile;
   // 1. Populate Connection Graph (CG) with Ideal nodes.
   Unique_Node_List worklist_init;
   worklist_init.map(C->unique(), NULL);  // preallocate space
   // Initialize worklist
   if (C->root() != NULL) {
     worklist_init.push(C->root());
   }
   GrowableArray<Node*> alloc_worklist;
   GrowableArray<Node*> addp_worklist;
   GrowableArray<Node*> ptr_cmp_worklist;
   PhaseGVN* igvn = _igvn;
   // Push all useful nodes onto CG list and set their type.
   for( uint next = 0; next < worklist_init.size(); ++next ) {
     Node* n = worklist_init.at(next);
     record_for_escape_analysis(n, igvn);
     // Only allocations and java static calls results are checked
     // for an escape status. See process_call_result() below.
     if (n->is_Allocate() || n->is_CallStaticJava() &&
         ptnode_adr(n->_idx)->node_type() == PointsToNode::JavaObject) {
       alloc_worklist.append(n);
     } else if(n->is_AddP()) {
       // Collect address nodes. Use them during stage 3 below
       // to build initial connection graph field edges.
       addp_worklist.append(n);
     } else if (n->is_MergeMem()) {
       // Collect all MergeMem nodes to add memory slices for
       // scalar replaceable objects in split_unique_types().
       _mergemem_worklist.append(n->as_MergeMem());
     } else if (OptimizePtrCompare && n->is_Cmp() &&
                (n->Opcode() == Op_CmpP || n->Opcode() == Op_CmpN)) {
       // Compare pointers nodes
       ptr_cmp_worklist.append(n);
     }
     for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
       Node* m = n->fast_out(i);   // Get user
       worklist_init.push(m);
     }
   }
   if (alloc_worklist.length() == 0) {
     _collecting = false;
     return false; // Nothing to do.
   }
   // 2. First pass to create simple CG edges (doesn't require to walk CG).
   uint delayed_size = _delayed_worklist.size();
   for( uint next = 0; next < delayed_size; ++next ) {
     Node* n = _delayed_worklist.at(next);
     build_connection_graph(n, igvn);
   }
   // 3. Pass to create initial fields edges (JavaObject -F-> AddP)
   //    to reduce number of iterations during stage 4 below.
   uint addp_length = addp_worklist.length();
   for( uint next = 0; next < addp_length; ++next ) {
     Node* n = addp_worklist.at(next);
     Node* base = get_addp_base(n);
     if (base->is_Proj() && base->in(0)->is_Call())
       base = base->in(0);
     PointsToNode::NodeType nt = ptnode_adr(base->_idx)->node_type();
     if (nt == PointsToNode::JavaObject) {
       build_connection_graph(n, igvn);
     }
   }
   GrowableArray<int> cg_worklist;
   cg_worklist.append(_phantom_object);
   GrowableArray<uint>  worklist;
   // 4. Build Connection Graph which need
   //    to walk the connection graph.
   _progress = false;
   for (uint ni = 0; ni < nodes_size(); ni++) {
     PointsToNode* ptn = ptnode_adr(ni);
     Node *n = ptn->_node;
     if (n != NULL) { // Call, AddP, LoadP, StoreP
       build_connection_graph(n, igvn);
       if (ptn->node_type() != PointsToNode::UnknownType)
         cg_worklist.append(n->_idx); // Collect CG nodes
       if (!_processed.test(n->_idx))
         worklist.append(n->_idx); // Collect C/A/L/S nodes
     }
   }
   // After IGVN user nodes may have smaller _idx than
   // their inputs so they will be processed first in
   // previous loop. Because of that not all Graph
   // edges will be created. Walk over interesting
   // nodes again until no new edges are created.
   //
   // Normally only 1-3 passes needed to build
   // Connection Graph depending on graph complexity.
   // Observed 8 passes in jvm2008 compiler.compiler.
   // Set limit to 20 to catch situation when something
   // did go wrong and recompile the method without EA.
 #define CG_BUILD_ITER_LIMIT 20
   uint length = worklist.length();
   int iterations = 0;
   while(_progress && (iterations++ < CG_BUILD_ITER_LIMIT)) {
     _progress = false;
     for( uint next = 0; next < length; ++next ) {
       int ni = worklist.at(next);
       PointsToNode* ptn = ptnode_adr(ni);
       Node* n = ptn->_node;
       assert(n != NULL, "should be known node");
       build_connection_graph(n, igvn);
     }
   }
   if (iterations >= CG_BUILD_ITER_LIMIT) {
     assert(iterations < CG_BUILD_ITER_LIMIT,
            err_msg("infinite EA connection graph build with %d nodes and worklist size %d",
            nodes_size(), length));
     // Possible infinite build_connection_graph loop,
     // retry compilation without escape analysis.
     C->record_failure(C2Compiler::retry_no_escape_analysis());
     _collecting = false;
     return false;
   }
 #undef CG_BUILD_ITER_LIMIT
   // 5. Propagate escaped states.
   worklist.clear();
   // mark all nodes reachable from GlobalEscape nodes
   (void)propagate_escape_state(&cg_worklist, &worklist, PointsToNode::GlobalEscape);
   // mark all nodes reachable from ArgEscape nodes
   bool has_non_escaping_obj = propagate_escape_state(&cg_worklist, &worklist, PointsToNode::ArgEscape);
   Arena* arena = Thread::current()->resource_area();
   VectorSet visited(arena);
   // 6. Find fields initializing values for not escaped allocations
   uint alloc_length = alloc_worklist.length();
   for (uint next = 0; next < alloc_length; ++next) {
     Node* n = alloc_worklist.at(next);
     if (ptnode_adr(n->_idx)->escape_state() == PointsToNode::NoEscape) {
       has_non_escaping_obj = true;
       if (n->is_Allocate()) {
         find_init_values(n, &visited, igvn);
       }
     }
   }
   uint cg_length = cg_worklist.length();
   // Skip the rest of code if all objects escaped.
   if (!has_non_escaping_obj) {
     cg_length = 0;
     addp_length = 0;
   }
   for (uint next = 0; next < cg_length; ++next) {
     int ni = cg_worklist.at(next);
     PointsToNode* ptn = ptnode_adr(ni);
     PointsToNode::NodeType nt = ptn->node_type();
     if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) {
       if (ptn->edge_count() == 0) {
         // No values were found. Assume the value was set
         // outside this method - add edge to phantom object.
         add_pointsto_edge(ni, _phantom_object);
       }
     }
   }
   // 7. Remove deferred edges from the graph.
   for (uint next = 0; next < cg_length; ++next) {
     int ni = cg_worklist.at(next);
     PointsToNode* ptn = ptnode_adr(ni);
     PointsToNode::NodeType nt = ptn->node_type();
     if (nt == PointsToNode::LocalVar || nt == PointsToNode::Field) {
       remove_deferred(ni, &worklist, &visited);
     }
   }
   // 8. Adjust escape state of nonescaping objects.
   for (uint next = 0; next < addp_length; ++next) {
     Node* n = addp_worklist.at(next);
     adjust_escape_state(n);
   }
   // push all NoEscape nodes on the worklist
   worklist.clear();
   for( uint next = 0; next < cg_length; ++next ) {
     int nk = cg_worklist.at(next);
     if (ptnode_adr(nk)->escape_state() == PointsToNode::NoEscape &&
         !is_null_ptr(nk))
       worklist.push(nk);
   }
   alloc_worklist.clear();
   // Propagate scalar_replaceable value.
   while(worklist.length() > 0) {
     uint nk = worklist.pop();
     PointsToNode* ptn = ptnode_adr(nk);
     Node* n = ptn->_node;
     bool scalar_replaceable = ptn->scalar_replaceable();
     if (n->is_Allocate() && scalar_replaceable) {
       // Push scalar replaceable allocations on alloc_worklist
       // for processing in split_unique_types(). Note,
       // following code may change scalar_replaceable value.
       alloc_worklist.append(n);
     }
     uint e_cnt = ptn->edge_count();
     for (uint ei = 0; ei < e_cnt; ei++) {
       uint npi = ptn->edge_target(ei);
       if (is_null_ptr(npi))
         continue;
       PointsToNode *np = ptnode_adr(npi);
       if (np->escape_state() < PointsToNode::NoEscape) {
         set_escape_state(npi, PointsToNode::NoEscape);
         if (!scalar_replaceable) {
           np->set_scalar_replaceable(false);
         }
         worklist.push(npi);
       } else if (np->scalar_replaceable() && !scalar_replaceable) {
         np->set_scalar_replaceable(false);
         worklist.push(npi);
       }
     }
   }
   _collecting = false;
   assert(C->unique() == nodes_size(), "there should be no new ideal nodes during ConnectionGraph build");
   assert(ptnode_adr(_oop_null)->escape_state() == PointsToNode::NoEscape &&
          ptnode_adr(_oop_null)->edge_count() == 0, "sanity");
   if (UseCompressedOops) {
     assert(ptnode_adr(_noop_null)->escape_state() == PointsToNode::NoEscape &&
            ptnode_adr(_noop_null)->edge_count() == 0, "sanity");
   }
   if (EliminateLocks && has_non_escaping_obj) {
     // Mark locks before changing ideal graph.
     int cnt = C->macro_count();
     for( int i=0; i < cnt; i++ ) {
       Node *n = C->macro_node(i);
       if (n->is_AbstractLock()) { // Lock and Unlock nodes
         AbstractLockNode* alock = n->as_AbstractLock();
         if (!alock->is_eliminated() || alock->is_coarsened()) {
           PointsToNode::EscapeState es = escape_state(alock->obj_node());
           assert(es != PointsToNode::UnknownEscape, "should know");
           if (es != PointsToNode::UnknownEscape && es != PointsToNode::GlobalEscape) {
             if (!alock->is_eliminated()) {
               // Mark it eliminated to update any counters
               alock->set_eliminated();
             } else {
               // The lock could be marked eliminated by lock coarsening
               // code during first IGVN before EA. Clear coarsened flag
               // to eliminate all associated locks/unlocks and relock
               // during deoptimization.
               alock->clear_coarsened();
             }
           }
         }
       }
     }
   }
   if (OptimizePtrCompare && has_non_escaping_obj) {
     // Add ConI(#CC_GT) and ConI(#CC_EQ).
     _pcmp_neq = igvn->makecon(TypeInt::CC_GT);
     _pcmp_eq = igvn->makecon(TypeInt::CC_EQ);
     // Optimize objects compare.
     while (ptr_cmp_worklist.length() != 0) {
       Node *n = ptr_cmp_worklist.pop();
       Node *res = optimize_ptr_compare(n);
       if (res != NULL) {
 #ifndef PRODUCT
         if (PrintOptimizePtrCompare) {
           tty->print_cr("++++ Replaced: %d %s(%d,%d) --> %s", n->_idx, (n->Opcode() == Op_CmpP ? "CmpP" : "CmpN"), n->in(1)->_idx, n->in(2)->_idx, (res == _pcmp_eq ? "EQ" : "NotEQ"));
           if (Verbose) {
             n->dump(1);
           }
         }
 #endif
         _igvn->replace_node(n, res);
       }
     }
     // cleanup
     if (_pcmp_neq->outcnt() == 0)
       igvn->hash_delete(_pcmp_neq);
     if (_pcmp_eq->outcnt()  == 0)
       igvn->hash_delete(_pcmp_eq);
   }
 #ifndef PRODUCT
   if (PrintEscapeAnalysis) {
     dump(); // Dump ConnectionGraph
   }
 #endif
   bool has_scalar_replaceable_candidates = false;
   alloc_length = alloc_worklist.length();
   for (uint next = 0; next < alloc_length; ++next) {
     Node* n = alloc_worklist.at(next);
     PointsToNode* ptn = ptnode_adr(n->_idx);
     assert(ptn->escape_state() == PointsToNode::NoEscape, "sanity");
     if (ptn->scalar_replaceable()) {
       has_scalar_replaceable_candidates = true;
       break;
     }
   }
   if ( has_scalar_replaceable_candidates &&
        C->AliasLevel() >= 3 && EliminateAllocations ) {
     // Now use the escape information to create unique types for
     // scalar replaceable objects.
     split_unique_types(alloc_worklist);
     if (C->failing())  return false;
     C->print_method("After Escape Analysis", 2);
 #ifdef ASSERT
   } else if (Verbose && (PrintEscapeAnalysis || PrintEliminateAllocations)) {
     tty->print("=== No allocations eliminated for ");
     C->method()->print_short_name();
     if(!EliminateAllocations) {
       tty->print(" since EliminateAllocations is off ===");
     } else if(!has_scalar_replaceable_candidates) {
       tty->print(" since there are no scalar replaceable candidates ===");
     } else if(C->AliasLevel() < 3) {
       tty->print(" since AliasLevel < 3 ===");
     }
     tty->cr();
 #endif
   }
   return has_non_escaping_obj;
 }
 // Find fields initializing values for allocations.
 void ConnectionGraph::find_init_values(Node* alloc, VectorSet* visited, PhaseTransform* phase) {
   assert(alloc->is_Allocate(), "Should be called for Allocate nodes only");
   PointsToNode* pta = ptnode_adr(alloc->_idx);
   assert(pta->escape_state() == PointsToNode::NoEscape, "Not escaped Allocate nodes only");
   InitializeNode* ini = alloc->as_Allocate()->initialization();
   Compile* C = _compile;
   visited->Reset();
   // Check if a oop field's initializing value is recorded and add
   // a corresponding NULL field's value if it is not recorded.
   // Connection Graph does not record a default initialization by NULL
   // captured by Initialize node.
   //
   uint null_idx = UseCompressedOops ? _noop_null : _oop_null;
   uint ae_cnt = pta->edge_count();
   bool visited_bottom_offset = false;
   for (uint ei = 0; ei < ae_cnt; ei++) {
     uint nidx = pta->edge_target(ei); // Field (AddP)
     PointsToNode* ptn = ptnode_adr(nidx);
     assert(ptn->_node->is_AddP(), "Should be AddP nodes only");
     int offset = ptn->offset();
     if (offset == Type::OffsetBot) {
       if (!visited_bottom_offset) {
         visited_bottom_offset = true;
         // Check only oop fields.
         const Type* adr_type = ptn->_node->as_AddP()->bottom_type();
         if (!adr_type->isa_aryptr() ||
             (adr_type->isa_aryptr()->klass() == NULL) ||
              adr_type->isa_aryptr()->klass()->is_obj_array_klass()) {
           // OffsetBot is used to reference array's element,
           // always add reference to NULL since we don't
           // known which element is referenced.
           add_edge_from_fields(alloc->_idx, null_idx, offset);
         }
       }
     } else if (offset != oopDesc::klass_offset_in_bytes() &&
                !visited->test_set(offset)) {
       // Check only oop fields.
       const Type* adr_type = ptn->_node->as_AddP()->bottom_type();
       BasicType basic_field_type = T_INT;
       if (adr_type->isa_instptr()) {
         ciField* field = C->alias_type(adr_type->isa_instptr())->field();
         if (field != NULL) {
           basic_field_type = field->layout_type();
         } else {
           // Ignore non field load (for example, klass load)
         }
       } else if (adr_type->isa_aryptr()) {
         if (offset != arrayOopDesc::length_offset_in_bytes()) {
           const Type* elemtype = adr_type->isa_aryptr()->elem();
           basic_field_type = elemtype->array_element_basic_type();
         } else {
           // Ignore array length load
         }
 #ifdef ASSERT
       } else {
         // Raw pointers are used for initializing stores so skip it
         // since it should be recorded already
         Node* base = get_addp_base(ptn->_node);
         assert(adr_type->isa_rawptr() && base->is_Proj() &&
                (base->in(0) == alloc),"unexpected pointer type");
 #endif
       }
       if (basic_field_type == T_OBJECT ||
           basic_field_type == T_NARROWOOP ||
           basic_field_type == T_ARRAY) {
         Node* value = NULL;
         if (ini != NULL) {
           BasicType ft = UseCompressedOops ? T_NARROWOOP : T_OBJECT;
           Node* store = ini->find_captured_store(offset, type2aelembytes(ft), phase);
           if (store != NULL && store->is_Store()) {
             value = store->in(MemNode::ValueIn);
           } else if (ptn->edge_count() > 0) { // Are there oop stores?
             // Check for a store which follows allocation without branches.
             // For example, a volatile field store is not collected
             // by Initialize node. TODO: it would be nice to use idom() here.
             //
             // Search all references to the same field which use different
             // AddP nodes, for example, in the next case:
             //
             //    Point p[] = new Point[1];
             //    if ( x ) { p[0] = new Point(); p[0].x = x; }
             //    if ( p[0] != null ) { y = p[0].x; } // has CastPP
             //
             for (uint next = ei; (next < ae_cnt) && (value == NULL); next++) {
               uint fpi = pta->edge_target(next); // Field (AddP)
               PointsToNode *ptf = ptnode_adr(fpi);
               if (ptf->offset() == offset) {
                 Node* nf = ptf->_node;
                 for (DUIterator_Fast imax, i = nf->fast_outs(imax); i < imax; i++) {
                   store = nf->fast_out(i);
                   if (store->is_Store() && store->in(0) != NULL) {
                     Node* ctrl = store->in(0);
                     while(!(ctrl == ini || ctrl == alloc || ctrl == NULL ||
                             ctrl == C->root() || ctrl == C->top() || ctrl->is_Region() ||
                             ctrl->is_IfTrue() || ctrl->is_IfFalse())) {
                        ctrl = ctrl->in(0);
                     }
                     if (ctrl == ini || ctrl == alloc) {
                       value = store->in(MemNode::ValueIn);
                       break;
                     }
                   }
                 }
               }
             }
           }
         }
         if (value == NULL || value != ptnode_adr(value->_idx)->_node) {
           // A field's initializing value was not recorded. Add NULL.
           add_edge_from_fields(alloc->_idx, null_idx, offset);
         }
       }
     }
   }
 }
 // Adjust escape state after Connection Graph is built.
 void ConnectionGraph::adjust_escape_state(Node* n) {
   PointsToNode* ptn = ptnode_adr(n->_idx);
   assert(n->is_AddP(), "Should be called for AddP nodes only");
   // Search for objects which are not scalar replaceable
   // and mark them to propagate the state to referenced objects.
   //
   int offset = ptn->offset();
   Node* base = get_addp_base(n);
   VectorSet* ptset = PointsTo(base);
   int ptset_size = ptset->Size();
   // An object is not scalar replaceable if the field which may point
   // to it has unknown offset (unknown element of an array of objects).
   //
   if (offset == Type::OffsetBot) {
     uint e_cnt = ptn->edge_count();
     for (uint ei = 0; ei < e_cnt; ei++) {
       uint npi = ptn->edge_target(ei);
       ptnode_adr(npi)->set_scalar_replaceable(false);
     }
   }
   // Currently an object is not scalar replaceable if a LoadStore node
   // access its field since the field value is unknown after it.
   //
   bool has_LoadStore = false;
   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
     Node *use = n->fast_out(i);
     if (use->is_LoadStore()) {
       has_LoadStore = true;
       break;
     }
   }
   // An object is not scalar replaceable if the address points
   // to unknown field (unknown element for arrays, offset is OffsetBot).
   //
   // Or the address may point to more then one object. This may produce
   // the false positive result (set not scalar replaceable)
   // since the flow-insensitive escape analysis can't separate
   // the case when stores overwrite the field's value from the case
   // when stores happened on different control branches.
   //
   // Note: it will disable scalar replacement in some cases:
   //
   //    Point p[] = new Point[1];
   //    p[0] = new Point(); // Will be not scalar replaced
   //
   // but it will save us from incorrect optimizations in next cases:
   //
   //    Point p[] = new Point[1];
   //    if ( x ) p[0] = new Point(); // Will be not scalar replaced
   //
   if (ptset_size > 1 || ptset_size != 0 &&
       (has_LoadStore || offset == Type::OffsetBot)) {
     for( VectorSetI j(ptset); j.test(); ++j ) {
       ptnode_adr(j.elem)->set_scalar_replaceable(false);
     }
   }
 }
 // Propagate escape states to referenced nodes.
 bool ConnectionGraph::propagate_escape_state(GrowableArray<int>* cg_worklist,
                                              GrowableArray<uint>* worklist,
                                              PointsToNode::EscapeState esc_state) {
   bool has_java_obj = false;
   // push all nodes with the same escape state on the worklist
   uint cg_length = cg_worklist->length();
   for (uint next = 0; next < cg_length; ++next) {
     int nk = cg_worklist->at(next);
     if (ptnode_adr(nk)->escape_state() == esc_state)
       worklist->push(nk);
   }
   // mark all reachable nodes
   while (worklist->length() > 0) {
     int pt = worklist->pop();
     PointsToNode* ptn = ptnode_adr(pt);
     if (ptn->node_type() == PointsToNode::JavaObject &&
         !is_null_ptr(pt)) {
       has_java_obj = true;
       if (esc_state > PointsToNode::NoEscape) {
         // fields values are unknown if object escapes
         add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
       }
     }
     uint e_cnt = ptn->edge_count();
     for (uint ei = 0; ei < e_cnt; ei++) {
       uint npi = ptn->edge_target(ei);
       if (is_null_ptr(npi))
         continue;
       PointsToNode *np = ptnode_adr(npi);
       if (np->escape_state() < esc_state) {
         set_escape_state(npi, esc_state);
         worklist->push(npi);
       }
     }
   }
   // Has not escaping java objects
   return has_java_obj && (esc_state < PointsToNode::GlobalEscape);
 }
 // Optimize objects compare.
 Node* ConnectionGraph::optimize_ptr_compare(Node* n) {
   assert(OptimizePtrCompare, "sanity");
   // Clone returned Set since PointsTo() returns pointer
   // to the same structure ConnectionGraph.pt_ptset.
   VectorSet ptset1 = *PointsTo(n->in(1));
   VectorSet ptset2 = *PointsTo(n->in(2));
   // Check simple cases first.
   if (ptset1.Size() == 1) {
     uint pt1 = ptset1.getelem();
     PointsToNode* ptn1 = ptnode_adr(pt1);
     if (ptn1->escape_state() == PointsToNode::NoEscape) {
       if (ptset2.Size() == 1 && ptset2.getelem() == pt1) {
         // Comparing the same not escaping object.
         return _pcmp_eq;
       }
       Node* obj = ptn1->_node;
       // Comparing not escaping allocation.
       if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
           !ptset2.test(pt1)) {
         return _pcmp_neq; // This includes nullness check.
       }
     }
   } else if (ptset2.Size() == 1) {
     uint pt2 = ptset2.getelem();
     PointsToNode* ptn2 = ptnode_adr(pt2);
     if (ptn2->escape_state() == PointsToNode::NoEscape) {
       Node* obj = ptn2->_node;
       // Comparing not escaping allocation.
       if ((obj->is_Allocate() || obj->is_CallStaticJava()) &&
           !ptset1.test(pt2)) {
         return _pcmp_neq; // This includes nullness check.
       }
     }
   }
   if (!ptset1.disjoint(ptset2)) {
     return NULL; // Sets are not disjoint
   }
   // Sets are disjoint.
   bool set1_has_unknown_ptr = ptset1.test(_phantom_object) != 0;
   bool set2_has_unknown_ptr = ptset2.test(_phantom_object) != 0;
   bool set1_has_null_ptr   = (ptset1.test(_oop_null) | ptset1.test(_noop_null)) != 0;
   bool set2_has_null_ptr   = (ptset2.test(_oop_null) | ptset2.test(_noop_null)) != 0;
   if (set1_has_unknown_ptr && set2_has_null_ptr ||
       set2_has_unknown_ptr && set1_has_null_ptr) {
     // Check nullness of unknown object.
     return NULL;
   }
   // Disjointness by itself is not sufficient since
   // alias analysis is not complete for escaped objects.
   // Disjoint sets are definitely unrelated only when
   // at least one set has only not escaping objects.
   if (!set1_has_unknown_ptr && !set1_has_null_ptr) {
     bool has_only_non_escaping_alloc = true;
     for (VectorSetI i(&ptset1); i.test(); ++i) {
       uint pt = i.elem;
       PointsToNode* ptn = ptnode_adr(pt);
       Node* obj = ptn->_node;
       if (ptn->escape_state() != PointsToNode::NoEscape ||
           !(obj->is_Allocate() || obj->is_CallStaticJava())) {
         has_only_non_escaping_alloc = false;
         break;
       }
     }
     if (has_only_non_escaping_alloc) {
       return _pcmp_neq;
     }
   }
   if (!set2_has_unknown_ptr && !set2_has_null_ptr) {
     bool has_only_non_escaping_alloc = true;
     for (VectorSetI i(&ptset2); i.test(); ++i) {
       uint pt = i.elem;
       PointsToNode* ptn = ptnode_adr(pt);
       Node* obj = ptn->_node;
       if (ptn->escape_state() != PointsToNode::NoEscape ||
           !(obj->is_Allocate() || obj->is_CallStaticJava())) {
         has_only_non_escaping_alloc = false;
         break;
       }
     }
     if (has_only_non_escaping_alloc) {
       return _pcmp_neq;
     }
   }
   return NULL;
 }
 void ConnectionGraph::process_call_arguments(CallNode *call, PhaseTransform *phase) {
     bool is_arraycopy = false;
     switch (call->Opcode()) {
 #ifdef ASSERT
     case Op_Allocate:
     case Op_AllocateArray:
     case Op_Lock:
     case Op_Unlock:
       assert(false, "should be done already");
       break;
 #endif
     case Op_CallLeafNoFP:
       is_arraycopy = (call->as_CallLeaf()->_name != NULL &&
                       strstr(call->as_CallLeaf()->_name, "arraycopy") != 0);
       // fall through
     case Op_CallLeaf:
     {
       // Stub calls, objects do not escape but they are not scale replaceable.
       // Adjust escape state for outgoing arguments.
       const TypeTuple * d = call->tf()->domain();
       bool src_has_oops = false;
       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
         const Type* at = d->field_at(i);
         Node *arg = call->in(i)->uncast();
         const Type *aat = phase->type(arg);
         PointsToNode::EscapeState arg_esc = ptnode_adr(arg->_idx)->escape_state();
         if (!arg->is_top() && at->isa_ptr() && aat->isa_ptr() &&
             (is_arraycopy || arg_esc < PointsToNode::ArgEscape)) {
           assert(aat == Type::TOP || aat == TypePtr::NULL_PTR ||
                  aat->isa_ptr() != NULL, "expecting an Ptr");
           bool arg_has_oops = aat->isa_oopptr() &&
                               (aat->isa_oopptr()->klass() == NULL || aat->isa_instptr() ||
                                (aat->isa_aryptr() && aat->isa_aryptr()->klass()->is_obj_array_klass()));
           if (i == TypeFunc::Parms) {
             src_has_oops = arg_has_oops;
           }
           //
           // src or dst could be j.l.Object when other is basic type array:
           //
           //   arraycopy(char[],0,Object*,0,size);
           //   arraycopy(Object*,0,char[],0,size);
           //
           // Don't add edges from dst's fields in such cases.
           //
           bool arg_is_arraycopy_dest = src_has_oops && is_arraycopy &&
                                        arg_has_oops && (i > TypeFunc::Parms);
 #ifdef ASSERT
           if (!(is_arraycopy ||
                 call->as_CallLeaf()->_name != NULL &&
                 (strcmp(call->as_CallLeaf()->_name, "g1_wb_pre")  == 0 ||
                  strcmp(call->as_CallLeaf()->_name, "g1_wb_post") == 0 ))
           ) {
             call->dump();
             assert(false, "EA: unexpected CallLeaf");
           }
 #endif
           // Always process arraycopy's destination object since
           // we need to add all possible edges to references in
           // source object.
           if (arg_esc >= PointsToNode::ArgEscape &&
               !arg_is_arraycopy_dest) {
             continue;
           }
           set_escape_state(arg->_idx, PointsToNode::ArgEscape);
           Node* arg_base = arg;
           if (arg->is_AddP()) {
             //
             // The inline_native_clone() case when the arraycopy stub is called
             // after the allocation before Initialize and CheckCastPP nodes.
             // Or normal arraycopy for object arrays case.
             //
             // Set AddP's base (Allocate) as not scalar replaceable since
             // pointer to the base (with offset) is passed as argument.
             //
             arg_base = get_addp_base(arg);
           }
           VectorSet argset = *PointsTo(arg_base); // Clone set
           for( VectorSetI j(&argset); j.test(); ++j ) {
             uint pd = j.elem; // Destination object
             set_escape_state(pd, PointsToNode::ArgEscape);
             if (arg_is_arraycopy_dest) {
               PointsToNode* ptd = ptnode_adr(pd);
               // Conservatively reference an unknown object since
               // not all source's fields/elements may be known.
               add_edge_from_fields(pd, _phantom_object, Type::OffsetBot);
               Node *src = call->in(TypeFunc::Parms)->uncast();
               Node* src_base = src;
               if (src->is_AddP()) {
                 src_base  = get_addp_base(src);
               }
               // Create edges from destination's fields to
               // everything known source's fields could point to.
               for( VectorSetI s(PointsTo(src_base)); s.test(); ++s ) {
                 uint ps = s.elem;
                 bool has_bottom_offset = false;
                 for (uint fd = 0; fd < ptd->edge_count(); fd++) {
                   assert(ptd->edge_type(fd) == PointsToNode::FieldEdge, "expecting a field edge");
                   int fdi = ptd->edge_target(fd);
                   PointsToNode* pfd = ptnode_adr(fdi);
                   int offset = pfd->offset();
                   if (offset == Type::OffsetBot)
                     has_bottom_offset = true;
                   assert(offset != -1, "offset should be set");
                   add_deferred_edge_to_fields(fdi, ps, offset);
                 }
                 // Destination object may not have access (no field edge)
                 // to fields which are accessed in source object.
                 // As result no edges will be created to those source's
                 // fields and escape state of destination object will
                 // not be propagated to those fields.
                 //
                 // Mark source object as global escape except in
                 // the case with Type::OffsetBot field (which is
                 // common case for array elements access) when
                 // edges are created to all source's fields.
                 if (!has_bottom_offset) {
                   set_escape_state(ps, PointsToNode::GlobalEscape);
                 }
               }
             }
           }
         }
       }
       break;
     }
     case Op_CallStaticJava:
     // For a static call, we know exactly what method is being called.
     // Use bytecode estimator to record the call's escape affects
     {
       ciMethod *meth = call->as_CallJava()->method();
       BCEscapeAnalyzer *call_analyzer = (meth !=NULL) ? meth->get_bcea() : NULL;
       // fall-through if not a Java method or no analyzer information
       if (call_analyzer != NULL) {
         const TypeTuple * d = call->tf()->domain();
         bool copy_dependencies = false;
         for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
           const Type* at = d->field_at(i);
           int k = i - TypeFunc::Parms;
           Node *arg = call->in(i)->uncast();
           if (at->isa_oopptr() != NULL &&
               ptnode_adr(arg->_idx)->escape_state() < PointsToNode::GlobalEscape) {
             bool global_escapes = false;
             bool fields_escapes = false;
             if (!call_analyzer->is_arg_stack(k)) {
               // The argument global escapes, mark everything it could point to
               set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
               global_escapes = true;
             } else {
               if (!call_analyzer->is_arg_local(k)) {
                 // The argument itself doesn't escape, but any fields might
                 fields_escapes = true;
               }
               set_escape_state(arg->_idx, PointsToNode::ArgEscape);
               copy_dependencies = true;
             }
             for( VectorSetI j(PointsTo(arg)); j.test(); ++j ) {
               uint pt = j.elem;
               if (global_escapes) {
                 // The argument global escapes, mark everything it could point to
                 set_escape_state(pt, PointsToNode::GlobalEscape);
                 add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
               } else {
                 set_escape_state(pt, PointsToNode::ArgEscape);
                 if (fields_escapes) {
                   // The argument itself doesn't escape, but any fields might.
                   // Use OffsetTop to indicate such case.
                   add_edge_from_fields(pt, _phantom_object, Type::OffsetTop);
                 }
               }
             }
           }
         }
         if (copy_dependencies)
           call_analyzer->copy_dependencies(_compile->dependencies());
         break;
       }
     }
     default:
     // Fall-through here if not a Java method or no analyzer information
     // or some other type of call, assume the worst case: all arguments
     // globally escape.
     {
       // adjust escape state for  outgoing arguments
       const TypeTuple * d = call->tf()->domain();
       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
         const Type* at = d->field_at(i);
         if (at->isa_oopptr() != NULL) {
           Node *arg = call->in(i)->uncast();
           set_escape_state(arg->_idx, PointsToNode::GlobalEscape);
           for( VectorSetI j(PointsTo(arg)); j.test(); ++j ) {
             uint pt = j.elem;
             set_escape_state(pt, PointsToNode::GlobalEscape);
             add_edge_from_fields(pt, _phantom_object, Type::OffsetBot);
           }
         }
       }
     }
   }
 }
 void ConnectionGraph::process_call_result(ProjNode *resproj, PhaseTransform *phase) {
   CallNode   *call = resproj->in(0)->as_Call();
   uint    call_idx = call->_idx;
   uint resproj_idx = resproj->_idx;
   switch (call->Opcode()) {
     case Op_Allocate:
     {
       Node *k = call->in(AllocateNode::KlassNode);
       const TypeKlassPtr *kt = k->bottom_type()->isa_klassptr();
       assert(kt != NULL, "TypeKlassPtr  required.");
       ciKlass* cik = kt->klass();
       PointsToNode::EscapeState es;
       uint edge_to;
       if (cik->is_subclass_of(_compile->env()->Thread_klass()) ||
          !cik->is_instance_klass() || // StressReflectiveCode
           cik->as_instance_klass()->has_finalizer()) {
         es = PointsToNode::GlobalEscape;
         edge_to = _phantom_object; // Could not be worse
       } else {
         es = PointsToNode::NoEscape;
         edge_to = call_idx;
         assert(ptnode_adr(call_idx)->scalar_replaceable(), "sanity");
       }
       set_escape_state(call_idx, es);
       add_pointsto_edge(resproj_idx, edge_to);
       _processed.set(resproj_idx);
       break;
     }
     case Op_AllocateArray:
     {
       Node *k = call->in(AllocateNode::KlassNode);
       const TypeKlassPtr *kt = k->bottom_type()->isa_klassptr();
       assert(kt != NULL, "TypeKlassPtr  required.");
       ciKlass* cik = kt->klass();
       PointsToNode::EscapeState es;
       uint edge_to;
       if (!cik->is_array_klass()) { // StressReflectiveCode
         es = PointsToNode::GlobalEscape;
         edge_to = _phantom_object;
       } else {
         es = PointsToNode::NoEscape;
         edge_to = call_idx;
         assert(ptnode_adr(call_idx)->scalar_replaceable(), "sanity");
         int length = call->in(AllocateNode::ALength)->find_int_con(-1);
         if (length < 0 || length > EliminateAllocationArraySizeLimit) {
           // Not scalar replaceable if the length is not constant or too big.
           ptnode_adr(call_idx)->set_scalar_replaceable(false);
         }
       }
       set_escape_state(call_idx, es);
       add_pointsto_edge(resproj_idx, edge_to);
       _processed.set(resproj_idx);
       break;
     }
     case Op_CallStaticJava:
     // For a static call, we know exactly what method is being called.
     // Use bytecode estimator to record whether the call's return value escapes
     {
       bool done = true;
       const TypeTuple *r = call->tf()->range();
       const Type* ret_type = NULL;
       if (r->cnt() > TypeFunc::Parms)
         ret_type = r->field_at(TypeFunc::Parms);
       // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
       //        _multianewarray functions return a TypeRawPtr.
       if (ret_type == NULL || ret_type->isa_ptr() == NULL) {
         _processed.set(resproj_idx);
         break;  // doesn't return a pointer type
       }
       ciMethod *meth = call->as_CallJava()->method();
       const TypeTuple * d = call->tf()->domain();
       if (meth == NULL) {
         // not a Java method, assume global escape
         set_escape_state(call_idx, PointsToNode::GlobalEscape);
         add_pointsto_edge(resproj_idx, _phantom_object);
       } else {
         BCEscapeAnalyzer *call_analyzer = meth->get_bcea();
         bool copy_dependencies = false;
         if (call_analyzer->is_return_allocated()) {
           // Returns a newly allocated unescaped object, simply
           // update dependency information.
           // Mark it as NoEscape so that objects referenced by
           // it's fields will be marked as NoEscape at least.
           set_escape_state(call_idx, PointsToNode::NoEscape);
           ptnode_adr(call_idx)->set_scalar_replaceable(false);
           // Fields values are unknown
           add_edge_from_fields(call_idx, _phantom_object, Type::OffsetBot);
           add_pointsto_edge(resproj_idx, call_idx);
           copy_dependencies = true;
         } else {
           // determine whether any arguments are returned
           set_escape_state(call_idx, PointsToNode::ArgEscape);
           bool ret_arg = false;
           for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
             const Type* at = d->field_at(i);
             if (at->isa_oopptr() != NULL) {
               Node *arg = call->in(i)->uncast();
               if (call_analyzer->is_arg_returned(i - TypeFunc::Parms)) {
                 ret_arg = true;
                 PointsToNode *arg_esp = ptnode_adr(arg->_idx);
                 if (arg_esp->node_type() == PointsToNode::UnknownType)
                   done = false;
                 else if (arg_esp->node_type() == PointsToNode::JavaObject)
                   add_pointsto_edge(resproj_idx, arg->_idx);
                 else
                   add_deferred_edge(resproj_idx, arg->_idx);
               }
             }
           }
           if (done) {
             copy_dependencies = true;
             // is_return_local() is true when only arguments are returned.
             if (!ret_arg || !call_analyzer->is_return_local()) {
               // Returns unknown object.
               add_pointsto_edge(resproj_idx, _phantom_object);
             }
           }
         }
         if (copy_dependencies)
           call_analyzer->copy_dependencies(_compile->dependencies());
       }
       if (done)
         _processed.set(resproj_idx);
       break;
     }
     default:
     // Some other type of call, assume the worst case that the
     // returned value, if any, globally escapes.
     {
       const TypeTuple *r = call->tf()->range();
       if (r->cnt() > TypeFunc::Parms) {
         const Type* ret_type = r->field_at(TypeFunc::Parms);
         // Note:  we use isa_ptr() instead of isa_oopptr()  here because the
         //        _multianewarray functions return a TypeRawPtr.
         if (ret_type->isa_ptr() != NULL) {
           set_escape_state(call_idx, PointsToNode::GlobalEscape);
           add_pointsto_edge(resproj_idx, _phantom_object);
         }
       }
       _processed.set(resproj_idx);
     }
   }
 }
 // Populate Connection Graph with Ideal nodes and create simple
 // connection graph edges (do not need to check the node_type of inputs
 // or to call PointsTo() to walk the connection graph).
 void ConnectionGraph::record_for_escape_analysis(Node *n, PhaseTransform *phase) {
   if (_processed.test(n->_idx))
     return; // No need to redefine node's state.
   if (n->is_Call()) {
     // Arguments to allocation and locking don't escape.
     if (n->is_Allocate()) {
       add_node(n, PointsToNode::JavaObject, PointsToNode::UnknownEscape, true);
       record_for_optimizer(n);
     } else if (n->is_Lock() || n->is_Unlock()) {
       // Put Lock and Unlock nodes on IGVN worklist to process them during
       // the first IGVN optimization when escape information is still available.
       record_for_optimizer(n);
       _processed.set(n->_idx);
     } else {
       // Don't mark as processed since call's arguments have to be processed.
       PointsToNode::NodeType nt = PointsToNode::UnknownType;
       PointsToNode::EscapeState es = PointsToNode::UnknownEscape;
       // Check if a call returns an object.
       const TypeTuple *r = n->as_Call()->tf()->range();
       if (r->cnt() > TypeFunc::Parms &&
           r->field_at(TypeFunc::Parms)->isa_ptr() &&
           n->as_Call()->proj_out(TypeFunc::Parms) != NULL) {
         nt = PointsToNode::JavaObject;
         if (!n->is_CallStaticJava()) {
           // Since the called mathod is statically unknown assume
           // the worst case that the returned value globally escapes.
           es = PointsToNode::GlobalEscape;
         }
       }
       add_node(n, nt, es, false);
     }
     return;
   }
   // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
   // ThreadLocal has RawPrt type.
   switch (n->Opcode()) {
     case Op_AddP:
     {
       add_node(n, PointsToNode::Field, PointsToNode::UnknownEscape, false);
       break;
     }
     case Op_CastX2P:
     { // "Unsafe" memory access.
       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
       break;
     }
     case Op_CastPP:
     case Op_CheckCastPP:
     case Op_EncodeP:
     case Op_DecodeN:
     {
       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
       int ti = n->in(1)->_idx;
       PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
       if (nt == PointsToNode::UnknownType) {
         _delayed_worklist.push(n); // Process it later.
         break;
       } else if (nt == PointsToNode::JavaObject) {
         add_pointsto_edge(n->_idx, ti);
       } else {
         add_deferred_edge(n->_idx, ti);
       }
       _processed.set(n->_idx);
       break;
     }
     case Op_ConP:
     {
       // assume all pointer constants globally escape except for null
       PointsToNode::EscapeState es;
       if (phase->type(n) == TypePtr::NULL_PTR)
         es = PointsToNode::NoEscape;
       else
         es = PointsToNode::GlobalEscape;
       add_node(n, PointsToNode::JavaObject, es, true);
       break;
     }
     case Op_ConN:
     {
       // assume all narrow oop constants globally escape except for null
       PointsToNode::EscapeState es;
       if (phase->type(n) == TypeNarrowOop::NULL_PTR)
         es = PointsToNode::NoEscape;
       else
         es = PointsToNode::GlobalEscape;
       add_node(n, PointsToNode::JavaObject, es, true);
       break;
     }
     case Op_CreateEx:
     {
       // assume that all exception objects globally escape
       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
       break;
     }
     case Op_LoadKlass:
     case Op_LoadNKlass:
     {
       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, true);
       break;
     }
     case Op_LoadP:
     case Op_LoadN:
     {
       const Type *t = phase->type(n);
       if (t->make_ptr() == NULL) {
         _processed.set(n->_idx);
         return;
       }
       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
       break;
     }
     case Op_Parm:
     {
       _processed.set(n->_idx); // No need to redefine it state.
       uint con = n->as_Proj()->_con;
       if (con < TypeFunc::Parms)
         return;
       const Type *t = n->in(0)->as_Start()->_domain->field_at(con);
       if (t->isa_ptr() == NULL)
         return;
       // We have to assume all input parameters globally escape
       // (Note: passing 'false' since _processed is already set).
       add_node(n, PointsToNode::JavaObject, PointsToNode::GlobalEscape, false);
       break;
     }
     case Op_PartialSubtypeCheck:
     { // Produces Null or notNull and is used in CmpP.
       add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true);
       break;
     }
     case Op_Phi:
     {
       const Type *t = n->as_Phi()->type();
       if (t->make_ptr() == NULL) {
         // nothing to do if not an oop or narrow oop
         _processed.set(n->_idx);
         return;
       }
       add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
       uint i;
       for (i = 1; i < n->req() ; i++) {
         Node* in = n->in(i);
         if (in == NULL)
           continue;  // ignore NULL
         in = in->uncast();
         if (in->is_top() || in == n)
           continue;  // ignore top or inputs which go back this node
         int ti = in->_idx;
         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
         if (nt == PointsToNode::UnknownType) {
           break;
         } else if (nt == PointsToNode::JavaObject) {
           add_pointsto_edge(n->_idx, ti);
         } else {
           add_deferred_edge(n->_idx, ti);
         }
       }
       if (i >= n->req())
         _processed.set(n->_idx);
       else
         _delayed_worklist.push(n);
       break;
     }
     case Op_Proj:
     {
       // we are only interested in the oop result projection from a call
       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
         const TypeTuple *r = n->in(0)->as_Call()->tf()->range();
         assert(r->cnt() > TypeFunc::Parms, "sanity");
         if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
           add_node(n, PointsToNode::LocalVar, PointsToNode::UnknownEscape, false);
           int ti = n->in(0)->_idx;
           // The call may not be registered yet (since not all its inputs are registered)
           // if this is the projection from backbranch edge of Phi.
           if (ptnode_adr(ti)->node_type() != PointsToNode::UnknownType) {
             process_call_result(n->as_Proj(), phase);
           }
           if (!_processed.test(n->_idx)) {
             // The call's result may need to be processed later if the call
             // returns it's argument and the argument is not processed yet.
             _delayed_worklist.push(n);
           }
           break;
         }
       }
       _processed.set(n->_idx);
       break;
     }
     case Op_Return:
     {
       if( n->req() > TypeFunc::Parms &&
           phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
         // Treat Return value as LocalVar with GlobalEscape escape state.
         add_node(n, PointsToNode::LocalVar, PointsToNode::GlobalEscape, false);
         int ti = n->in(TypeFunc::Parms)->_idx;
         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
         if (nt == PointsToNode::UnknownType) {
           _delayed_worklist.push(n); // Process it later.
           break;
         } else if (nt == PointsToNode::JavaObject) {
           add_pointsto_edge(n->_idx, ti);
         } else {
           add_deferred_edge(n->_idx, ti);
         }
       }
       _processed.set(n->_idx);
       break;
     }
     case Op_StoreP:
     case Op_StoreN:
     {
       const Type *adr_type = phase->type(n->in(MemNode::Address));
       adr_type = adr_type->make_ptr();
       if (adr_type->isa_oopptr()) {
         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
       } else {
         Node* adr = n->in(MemNode::Address);
         if (adr->is_AddP() && phase->type(adr) == TypeRawPtr::NOTNULL &&
             adr->in(AddPNode::Address)->is_Proj() &&
             adr->in(AddPNode::Address)->in(0)->is_Allocate()) {
           add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
           // We are computing a raw address for a store captured
           // by an Initialize compute an appropriate address type.
           int offs = (int)phase->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
           assert(offs != Type::OffsetBot, "offset must be a constant");
         } else {
           _processed.set(n->_idx);
           return;
         }
       }
       break;
     }
     case Op_StorePConditional:
     case Op_CompareAndSwapP:
     case Op_CompareAndSwapN:
     {
       const Type *adr_type = phase->type(n->in(MemNode::Address));
       adr_type = adr_type->make_ptr();
       if (adr_type->isa_oopptr()) {
         add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
       } else {
         _processed.set(n->_idx);
         return;
       }
       break;
     }
     case Op_AryEq:
     case Op_StrComp:
     case Op_StrEquals:
     case Op_StrIndexOf:
     {
       // char[] arrays passed to string intrinsics are not scalar replaceable.
       add_node(n, PointsToNode::UnknownType, PointsToNode::UnknownEscape, false);
       break;
     }
     case Op_ThreadLocal:
     {
       add_node(n, PointsToNode::JavaObject, PointsToNode::ArgEscape, true);
       break;
     }
     default:
       ;
       // nothing to do
   }
   return;
 }
 void ConnectionGraph::build_connection_graph(Node *n, PhaseTransform *phase) {
   uint n_idx = n->_idx;
   assert(ptnode_adr(n_idx)->_node != NULL, "node should be registered");
   // Don't set processed bit for AddP, LoadP, StoreP since
   // they may need more then one pass to process.
   // Also don't mark as processed Call nodes since their
   // arguments may need more then one pass to process.
   if (_processed.test(n_idx))
     return; // No need to redefine node's state.
   if (n->is_Call()) {
     CallNode *call = n->as_Call();
     process_call_arguments(call, phase);
     return;
   }
   switch (n->Opcode()) {
     case Op_AddP:
     {
       Node *base = get_addp_base(n);
       int offset = address_offset(n, phase);
       // Create a field edge to this node from everything base could point to.
       for( VectorSetI i(PointsTo(base)); i.test(); ++i ) {
         uint pt = i.elem;
         add_field_edge(pt, n_idx, offset);
       }
       break;
     }
     case Op_CastX2P:
     {
       assert(false, "Op_CastX2P");
       break;
     }
     case Op_CastPP:
     case Op_CheckCastPP:
     case Op_EncodeP:
     case Op_DecodeN:
     {
       int ti = n->in(1)->_idx;
       assert(ptnode_adr(ti)->node_type() != PointsToNode::UnknownType, "all nodes should be registered");
       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
         add_pointsto_edge(n_idx, ti);
       } else {
         add_deferred_edge(n_idx, ti);
       }
       _processed.set(n_idx);
       break;
     }
     case Op_ConP:
     {
       assert(false, "Op_ConP");
       break;
     }
     case Op_ConN:
     {
       assert(false, "Op_ConN");
       break;
     }
     case Op_CreateEx:
     {
       assert(false, "Op_CreateEx");
       break;
     }
     case Op_LoadKlass:
     case Op_LoadNKlass:
     {
       assert(false, "Op_LoadKlass");
       break;
     }
     case Op_LoadP:
     case Op_LoadN:
     {
       const Type *t = phase->type(n);
 #ifdef ASSERT
       if (t->make_ptr() == NULL)
         assert(false, "Op_LoadP");
 #endif
       Node* adr = n->in(MemNode::Address)->uncast();
       Node* adr_base;
       if (adr->is_AddP()) {
         adr_base = get_addp_base(adr);
       } else {
         adr_base = adr;
       }
       // For everything "adr_base" could point to, create a deferred edge from
       // this node to each field with the same offset.
       int offset = address_offset(adr, phase);
       for( VectorSetI i(PointsTo(adr_base)); i.test(); ++i ) {
         uint pt = i.elem;
         if (adr->is_AddP()) {
           // Add field edge if it is missing.
           add_field_edge(pt, adr->_idx, offset);
         }
         add_deferred_edge_to_fields(n_idx, pt, offset);
       }
       break;
     }
     case Op_Parm:
     {
       assert(false, "Op_Parm");
       break;
     }
     case Op_PartialSubtypeCheck:
     {
       assert(false, "Op_PartialSubtypeCheck");
       break;
     }
     case Op_Phi:
     {
 #ifdef ASSERT
       const Type *t = n->as_Phi()->type();
       if (t->make_ptr() == NULL)
         assert(false, "Op_Phi");
 #endif
       for (uint i = 1; i < n->req() ; i++) {
         Node* in = n->in(i);
         if (in == NULL)
           continue;  // ignore NULL
         in = in->uncast();
         if (in->is_top() || in == n)
           continue;  // ignore top or inputs which go back this node
         int ti = in->_idx;
         PointsToNode::NodeType nt = ptnode_adr(ti)->node_type();
         assert(nt != PointsToNode::UnknownType, "all nodes should be known");
         if (nt == PointsToNode::JavaObject) {
           add_pointsto_edge(n_idx, ti);
         } else {
           add_deferred_edge(n_idx, ti);
         }
       }
       _processed.set(n_idx);
       break;
     }
     case Op_Proj:
     {
       // we are only interested in the oop result projection from a call
       if (n->as_Proj()->_con == TypeFunc::Parms && n->in(0)->is_Call() ) {
         assert(ptnode_adr(n->in(0)->_idx)->node_type() != PointsToNode::UnknownType,
                "all nodes should be registered");
         const TypeTuple *r = n->in(0)->as_Call()->tf()->range();
         assert(r->cnt() > TypeFunc::Parms, "sanity");
         if (r->field_at(TypeFunc::Parms)->isa_ptr() != NULL) {
           process_call_result(n->as_Proj(), phase);
           assert(_processed.test(n_idx), "all call results should be processed");
           break;
         }
       }
       assert(false, "Op_Proj");
       break;
     }
     case Op_Return:
     {
 #ifdef ASSERT
       if( n->req() <= TypeFunc::Parms ||
           !phase->type(n->in(TypeFunc::Parms))->isa_oopptr() ) {
         assert(false, "Op_Return");
       }
 #endif
       int ti = n->in(TypeFunc::Parms)->_idx;
       assert(ptnode_adr(ti)->node_type() != PointsToNode::UnknownType, "node should be registered");
       if (ptnode_adr(ti)->node_type() == PointsToNode::JavaObject) {
         add_pointsto_edge(n_idx, ti);
       } else {
         add_deferred_edge(n_idx, ti);
       }
       _processed.set(n_idx);
       break;
     }
     case Op_StoreP:
     case Op_StoreN:
     case Op_StorePConditional:
     case Op_CompareAndSwapP:
     case Op_CompareAndSwapN:
     {
       Node *adr = n->in(MemNode::Address);
       const Type *adr_type = phase->type(adr)->make_ptr();
 #ifdef ASSERT
       if (!adr_type->isa_oopptr())
         assert(phase->type(adr) == TypeRawPtr::NOTNULL, "Op_StoreP");
 #endif
       assert(adr->is_AddP(), "expecting an AddP");
       Node *adr_base = get_addp_base(adr);
       Node *val = n->in(MemNode::ValueIn)->uncast();
       int offset = address_offset(adr, phase);
       // For everything "adr_base" could point to, create a deferred edge
       // to "val" from each field with the same offset.
       for( VectorSetI i(PointsTo(adr_base)); i.test(); ++i ) {
         uint pt = i.elem;
         // Add field edge if it is missing.
         add_field_edge(pt, adr->_idx, offset);
         add_edge_from_fields(pt, val->_idx, offset);
       }
       break;
     }
     case Op_AryEq:
     case Op_StrComp:
     case Op_StrEquals:
     case Op_StrIndexOf:
     {
       // char[] arrays passed to string intrinsic do not escape but
       // they are not scalar replaceable. Adjust escape state for them.
       // Start from in(2) edge since in(1) is memory edge.
       for (uint i = 2; i < n->req(); i++) {
         Node* adr = n->in(i)->uncast();
         const Type *at = phase->type(adr);
         if (!adr->is_top() && at->isa_ptr()) {
           assert(at == Type::TOP || at == TypePtr::NULL_PTR ||
                  at->isa_ptr() != NULL, "expecting an Ptr");
           if (adr->is_AddP()) {
             adr = get_addp_base(adr);
           }
           // Mark as ArgEscape everything "adr" could point to.
           set_escape_state(adr->_idx, PointsToNode::ArgEscape);
         }
       }
       _processed.set(n_idx);
       break;
     }
     case Op_ThreadLocal:
     {
       assert(false, "Op_ThreadLocal");
       break;
     }
     default:
       // This method should be called only for EA specific nodes.
       ShouldNotReachHere();
   }
 }
 #ifndef PRODUCT
 void ConnectionGraph::dump() {
   bool first = true;
   uint size = nodes_size();
   for (uint ni = 0; ni < size; ni++) {
     PointsToNode *ptn = ptnode_adr(ni);
     PointsToNode::NodeType ptn_type = ptn->node_type();
     if (ptn_type != PointsToNode::JavaObject || ptn->_node == NULL)
       continue;
     PointsToNode::EscapeState es = escape_state(ptn->_node);
     if (ptn->_node->is_Allocate() && (es == PointsToNode::NoEscape || Verbose)) {
       if (first) {
         tty->cr();
         tty->print("======== Connection graph for ");
         _compile->method()->print_short_name();
         tty->cr();
         first = false;
       }
       tty->print("%6d ", ni);
       ptn->dump();
       // Print all locals which reference this allocation
       for (uint li = ni; li < size; li++) {
         PointsToNode *ptn_loc = ptnode_adr(li);
         PointsToNode::NodeType ptn_loc_type = ptn_loc->node_type();
         if ( ptn_loc_type == PointsToNode::LocalVar && ptn_loc->_node != NULL &&
              ptn_loc->edge_count() == 1 && ptn_loc->edge_target(0) == ni ) {
           ptnode_adr(li)->dump(false);
         }
       }
       if (Verbose) {
         // Print all fields which reference this allocation
         for (uint i = 0; i < ptn->edge_count(); i++) {
           uint ei = ptn->edge_target(i);
           ptnode_adr(ei)->dump(false);
         }
       }
       tty->cr();
     }
   }
 }
 #endif

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/opto/escape.cpp@cc81b9c09bbb (annotated)

src/share/vm/opto/escape.cpp