changeset 53536:40474b7105f4

8213615: GC/C2 abstraction for escape analysis Reviewed-by: kvn, roland
author rkennke
date Thu, 15 Nov 2018 10:59:56 +0100
parents 9111de8b09a1
children 1a534c7926cc
files src/hotspot/share/gc/g1/c2/g1BarrierSetC2.cpp src/hotspot/share/gc/g1/c2/g1BarrierSetC2.hpp src/hotspot/share/gc/shared/c2/barrierSetC2.hpp src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp src/hotspot/share/opto/escape.cpp src/hotspot/share/opto/escape.hpp
diffstat 7 files changed, 223 insertions(+), 152 deletions(-) [+]
line wrap: on
line diff
--- a/src/hotspot/share/gc/g1/c2/g1BarrierSetC2.cpp	Wed Nov 14 23:12:19 2018 -0800
+++ b/src/hotspot/share/gc/g1/c2/g1BarrierSetC2.cpp	Thu Nov 15 10:59:56 2018 +0100
@@ -31,6 +31,7 @@
 #include "gc/g1/heapRegion.hpp"
 #include "opto/arraycopynode.hpp"
 #include "opto/compile.hpp"
+#include "opto/escape.hpp"
 #include "opto/graphKit.hpp"
 #include "opto/idealKit.hpp"
 #include "opto/macro.hpp"
@@ -840,3 +841,32 @@
   }
 }
 #endif
+
+bool G1BarrierSetC2::escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const {
+  if (opcode == Op_StoreP) {
+    Node* adr = n->in(MemNode::Address);
+    const Type* adr_type = gvn->type(adr);
+    // Pointer stores in G1 barriers looks like unsafe access.
+    // Ignore such stores to be able scalar replace non-escaping
+    // allocations.
+    if (adr_type->isa_rawptr() && adr->is_AddP()) {
+      Node* base = conn_graph->get_addp_base(adr);
+      if (base->Opcode() == Op_LoadP &&
+          base->in(MemNode::Address)->is_AddP()) {
+        adr = base->in(MemNode::Address);
+        Node* tls = conn_graph->get_addp_base(adr);
+        if (tls->Opcode() == Op_ThreadLocal) {
+          int offs = (int) gvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
+          const int buf_offset = in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset());
+          if (offs == buf_offset) {
+            return true; // G1 pre barrier previous oop value store.
+          }
+          if (offs == in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset())) {
+            return true; // G1 post barrier card address store.
+          }
+        }
+      }
+    }
+  }
+  return false;
+}
--- a/src/hotspot/share/gc/g1/c2/g1BarrierSetC2.hpp	Wed Nov 14 23:12:19 2018 -0800
+++ b/src/hotspot/share/gc/g1/c2/g1BarrierSetC2.hpp	Thu Nov 15 10:59:56 2018 +0100
@@ -92,6 +92,8 @@
 #ifdef ASSERT
   virtual void verify_gc_barriers(Compile* compile, CompilePhase phase) const;
 #endif
+
+  virtual bool escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const;
 };
 
 #endif // SHARE_GC_SHARED_C2_G1BARRIERSETC2_HPP
--- a/src/hotspot/share/gc/shared/c2/barrierSetC2.hpp	Wed Nov 14 23:12:19 2018 -0800
+++ b/src/hotspot/share/gc/shared/c2/barrierSetC2.hpp	Thu Nov 15 10:59:56 2018 +0100
@@ -55,12 +55,15 @@
 const DecoratorSet C2_ARRAY_COPY             = DECORATOR_LAST << 10;
 
 class Compile;
+class ConnectionGraph;
 class GraphKit;
 class IdealKit;
 class Node;
+class PhaseGVN;
+class PhaseMacroExpand;
 class Type;
 class TypePtr;
-class PhaseMacroExpand;
+class Unique_Node_List;
 
 // This class wraps a node and a type.
 class C2AccessValue: public StackObj {
@@ -291,6 +294,10 @@
 
   virtual bool final_graph_reshaping(Compile* compile, Node* n, uint opcode) const { return false; }
 
+  virtual bool escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const { return false; }
+  virtual bool escape_add_final_edges(ConnectionGraph* conn_graph, PhaseGVN* gvn, Node* n, uint opcode) const { return false; }
+  virtual bool escape_has_out_with_unsafe_object(Node* n) const { return false; }
+  virtual bool escape_is_barrier_node(Node* n) const { return false; }
 };
 
 #endif // SHARE_GC_SHARED_C2_BARRIERSETC2_HPP
--- a/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp	Wed Nov 14 23:12:19 2018 -0800
+++ b/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp	Thu Nov 15 10:59:56 2018 +0100
@@ -24,6 +24,7 @@
 #include "precompiled.hpp"
 #include "opto/compile.hpp"
 #include "opto/castnode.hpp"
+#include "opto/escape.hpp"
 #include "opto/graphKit.hpp"
 #include "opto/idealKit.hpp"
 #include "opto/loopnode.hpp"
@@ -1571,3 +1572,44 @@
 }
 
 #endif
+
+bool ZBarrierSetC2::escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const {
+  switch (opcode) {
+    case Op_LoadBarrierSlowReg:
+    case Op_LoadBarrierWeakSlowReg:
+      conn_graph->add_objload_to_connection_graph(n, delayed_worklist);
+      return true;
+    case Op_Proj:
+      if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) {
+        conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop),
+                                           delayed_worklist);
+        return true;
+      }
+    default:
+      break;
+  }
+  return false;
+}
+
+bool ZBarrierSetC2::escape_add_final_edges(ConnectionGraph* conn_graph, PhaseGVN* gvn, Node* n, uint opcode) const {
+  switch (opcode) {
+    case Op_LoadBarrierSlowReg:
+    case Op_LoadBarrierWeakSlowReg: {
+      const Type *t = gvn->type(n);
+      if (t->make_ptr() != NULL) {
+        Node *adr = n->in(MemNode::Address);
+        conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
+        return true;
+      }
+    }
+    case Op_Proj: {
+      if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) {
+        conn_graph->add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), NULL);
+        return true;
+      }
+    }
+    default:
+      break;
+  }
+  return false;
+}
\ No newline at end of file
--- a/src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp	Wed Nov 14 23:12:19 2018 -0800
+++ b/src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp	Thu Nov 15 10:59:56 2018 +0100
@@ -212,6 +212,10 @@
 #ifdef ASSERT
   virtual void verify_gc_barriers(Compile* compile, CompilePhase phase) const;
 #endif
+
+  virtual bool escape_add_to_con_graph(ConnectionGraph* conn_graph, PhaseGVN* gvn, Unique_Node_List* delayed_worklist, Node* n, uint opcode) const;
+  virtual bool escape_add_final_edges(ConnectionGraph* conn_graph, PhaseGVN* gvn, Node* n, uint opcode) const;
+
 };
 
 #endif // SHARE_GC_Z_C2_ZBARRIERSETC2_HPP
--- a/src/hotspot/share/opto/escape.cpp	Wed Nov 14 23:12:19 2018 -0800
+++ b/src/hotspot/share/opto/escape.cpp	Thu Nov 15 10:59:56 2018 +0100
@@ -25,6 +25,7 @@
 #include "precompiled.hpp"
 #include "ci/bcEscapeAnalyzer.hpp"
 #include "compiler/compileLog.hpp"
+#include "gc/shared/barrierSet.hpp"
 #include "gc/shared/c2/barrierSetC2.hpp"
 #include "libadt/vectset.hpp"
 #include "memory/allocation.hpp"
@@ -39,12 +40,6 @@
 #include "opto/movenode.hpp"
 #include "opto/rootnode.hpp"
 #include "utilities/macros.hpp"
-#if INCLUDE_G1GC
-#include "gc/g1/g1ThreadLocalData.hpp"
-#endif // INCLUDE_G1GC
-#if INCLUDE_ZGC
-#include "gc/z/c2/zBarrierSetC2.hpp"
-#endif
 
 ConnectionGraph::ConnectionGraph(Compile * C, PhaseIterGVN *igvn) :
   _nodes(C->comp_arena(), C->unique(), C->unique(), NULL),
@@ -388,6 +383,10 @@
     return; // Skip predefined nodes.
 
   int opcode = n->Opcode();
+  bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_to_con_graph(this, igvn, delayed_worklist, n, opcode);
+  if (gc_handled) {
+    return; // Ignore node if already handled by GC.
+  }
   switch (opcode) {
     case Op_AddP: {
       Node* base = get_addp_base(n);
@@ -453,10 +452,6 @@
       break;
     }
     case Op_LoadP:
-#if INCLUDE_ZGC
-    case Op_LoadBarrierSlowReg:
-    case Op_LoadBarrierWeakSlowReg:
-#endif
     case Op_LoadN:
     case Op_LoadPLocked: {
       add_objload_to_connection_graph(n, delayed_worklist);
@@ -491,13 +486,6 @@
         add_local_var_and_edge(n, PointsToNode::NoEscape,
                                n->in(0), delayed_worklist);
       }
-#if INCLUDE_ZGC
-      else if (UseZGC) {
-        if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) {
-          add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), delayed_worklist);
-        }
-      }
-#endif
       break;
     }
     case Op_Rethrow: // Exception object escapes
@@ -525,62 +513,7 @@
     case Op_WeakCompareAndSwapN:
     case Op_CompareAndSwapP:
     case Op_CompareAndSwapN: {
-      Node* adr = n->in(MemNode::Address);
-      const Type *adr_type = igvn->type(adr);
-      adr_type = adr_type->make_ptr();
-      if (adr_type == NULL) {
-        break; // skip dead nodes
-      }
-      if (   adr_type->isa_oopptr()
-          || (   (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
-              && adr_type == TypeRawPtr::NOTNULL
-              && adr->in(AddPNode::Address)->is_Proj()
-              && adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
-        delayed_worklist->push(n); // Process it later.
-#ifdef ASSERT
-        assert(adr->is_AddP(), "expecting an AddP");
-        if (adr_type == TypeRawPtr::NOTNULL) {
-          // Verify a raw address for a store captured by Initialize node.
-          int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
-          assert(offs != Type::OffsetBot, "offset must be a constant");
-        }
-#endif
-      } else {
-        // Ignore copy the displaced header to the BoxNode (OSR compilation).
-        if (adr->is_BoxLock())
-          break;
-        // Stored value escapes in unsafe access.
-        if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
-          // Pointer stores in G1 barriers looks like unsafe access.
-          // Ignore such stores to be able scalar replace non-escaping
-          // allocations.
-#if INCLUDE_G1GC
-          if (UseG1GC && adr->is_AddP()) {
-            Node* base = get_addp_base(adr);
-            if (base->Opcode() == Op_LoadP &&
-                base->in(MemNode::Address)->is_AddP()) {
-              adr = base->in(MemNode::Address);
-              Node* tls = get_addp_base(adr);
-              if (tls->Opcode() == Op_ThreadLocal) {
-                int offs = (int)igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
-                if (offs == in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset())) {
-                  break; // G1 pre barrier previous oop value store.
-                }
-                if (offs == in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset())) {
-                  break; // G1 post barrier card address store.
-                }
-              }
-            }
-          }
-#endif
-          delayed_worklist->push(n); // Process unsafe access later.
-          break;
-        }
-#ifdef ASSERT
-        n->dump(1);
-        assert(false, "not unsafe or G1 barrier raw StoreP");
-#endif
-      }
+      add_to_congraph_unsafe_access(n, opcode, delayed_worklist);
       break;
     }
     case Op_AryEq:
@@ -633,6 +566,10 @@
          (n_ptn != NULL) && (n_ptn->ideal_node() != NULL),
          "node should be registered already");
   int opcode = n->Opcode();
+  bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->escape_add_final_edges(this, _igvn, n, opcode);
+  if (gc_handled) {
+    return; // Ignore node if already handled by GC.
+  }
   switch (opcode) {
     case Op_AddP: {
       Node* base = get_addp_base(n);
@@ -666,10 +603,6 @@
       break;
     }
     case Op_LoadP:
-#if INCLUDE_ZGC
-    case Op_LoadBarrierSlowReg:
-    case Op_LoadBarrierWeakSlowReg:
-#endif
     case Op_LoadN:
     case Op_LoadPLocked: {
       // Using isa_ptr() instead of isa_oopptr() for LoadP and Phi because
@@ -709,14 +642,6 @@
         add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0), NULL);
         break;
       }
-#if INCLUDE_ZGC
-      else if (UseZGC) {
-        if (n->as_Proj()->_con == LoadBarrierNode::Oop && n->in(0)->is_LoadBarrier()) {
-          add_local_var_and_edge(n, PointsToNode::NoEscape, n->in(0)->in(LoadBarrierNode::Oop), NULL);
-          break;
-        }
-      }
-#endif
       ELSE_FAIL("Op_Proj");
     }
     case Op_Rethrow: // Exception object escapes
@@ -742,47 +667,7 @@
     case Op_WeakCompareAndSwapN:
     case Op_GetAndSetP:
     case Op_GetAndSetN: {
-      Node* adr = n->in(MemNode::Address);
-      const Type *adr_type = _igvn->type(adr);
-      adr_type = adr_type->make_ptr();
-#ifdef ASSERT
-      if (adr_type == NULL) {
-        n->dump(1);
-        assert(adr_type != NULL, "dead node should not be on list");
-        break;
-      }
-#endif
-      if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN ||
-          opcode == Op_CompareAndExchangeN || opcode == Op_CompareAndExchangeP) {
-        add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
-      }
-      if (   adr_type->isa_oopptr()
-          || (   (opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
-              && adr_type == TypeRawPtr::NOTNULL
-              && adr->in(AddPNode::Address)->is_Proj()
-              && adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
-        // Point Address to Value
-        PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
-        assert(adr_ptn != NULL &&
-               adr_ptn->as_Field()->is_oop(), "node should be registered");
-        Node *val = n->in(MemNode::ValueIn);
-        PointsToNode* ptn = ptnode_adr(val->_idx);
-        assert(ptn != NULL, "node should be registered");
-        add_edge(adr_ptn, ptn);
-        break;
-      } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
-        // Stored value escapes in unsafe access.
-        Node *val = n->in(MemNode::ValueIn);
-        PointsToNode* ptn = ptnode_adr(val->_idx);
-        assert(ptn != NULL, "node should be registered");
-        set_escape_state(ptn, PointsToNode::GlobalEscape);
-        // Add edge to object for unsafe access with offset.
-        PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
-        assert(adr_ptn != NULL, "node should be registered");
-        if (adr_ptn->is_Field()) {
-          assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
-          add_edge(adr_ptn, ptn);
-        }
+      if (add_final_edges_unsafe_access(n, opcode)) {
         break;
       }
       ELSE_FAIL("Op_StoreP");
@@ -827,6 +712,93 @@
   return;
 }
 
+void ConnectionGraph::add_to_congraph_unsafe_access(Node* n, uint opcode, Unique_Node_List* delayed_worklist) {
+  Node* adr = n->in(MemNode::Address);
+  const Type* adr_type = _igvn->type(adr);
+  adr_type = adr_type->make_ptr();
+  if (adr_type == NULL) {
+    return; // skip dead nodes
+  }
+  if (adr_type->isa_oopptr()
+      || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
+          && adr_type == TypeRawPtr::NOTNULL
+          && adr->in(AddPNode::Address)->is_Proj()
+          && adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
+    delayed_worklist->push(n); // Process it later.
+#ifdef ASSERT
+    assert (adr->is_AddP(), "expecting an AddP");
+    if (adr_type == TypeRawPtr::NOTNULL) {
+      // Verify a raw address for a store captured by Initialize node.
+      int offs = (int) _igvn->find_intptr_t_con(adr->in(AddPNode::Offset), Type::OffsetBot);
+      assert(offs != Type::OffsetBot, "offset must be a constant");
+    }
+#endif
+  } else {
+    // Ignore copy the displaced header to the BoxNode (OSR compilation).
+    if (adr->is_BoxLock()) {
+      return;
+    }
+    // Stored value escapes in unsafe access.
+    if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
+      delayed_worklist->push(n); // Process unsafe access later.
+      return;
+    }
+#ifdef ASSERT
+    n->dump(1);
+    assert(false, "not unsafe");
+#endif
+  }
+}
+
+bool ConnectionGraph::add_final_edges_unsafe_access(Node* n, uint opcode) {
+  Node* adr = n->in(MemNode::Address);
+  const Type *adr_type = _igvn->type(adr);
+  adr_type = adr_type->make_ptr();
+#ifdef ASSERT
+  if (adr_type == NULL) {
+    n->dump(1);
+    assert(adr_type != NULL, "dead node should not be on list");
+    return true;
+  }
+#endif
+
+  if (opcode == Op_GetAndSetP || opcode == Op_GetAndSetN ||
+      opcode == Op_CompareAndExchangeN || opcode == Op_CompareAndExchangeP) {
+    add_local_var_and_edge(n, PointsToNode::NoEscape, adr, NULL);
+  }
+
+  if (adr_type->isa_oopptr()
+      || ((opcode == Op_StoreP || opcode == Op_StoreN || opcode == Op_StoreNKlass)
+           && adr_type == TypeRawPtr::NOTNULL
+           && adr->in(AddPNode::Address)->is_Proj()
+           && adr->in(AddPNode::Address)->in(0)->is_Allocate())) {
+    // Point Address to Value
+    PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
+    assert(adr_ptn != NULL &&
+           adr_ptn->as_Field()->is_oop(), "node should be registered");
+    Node* val = n->in(MemNode::ValueIn);
+    PointsToNode* ptn = ptnode_adr(val->_idx);
+    assert(ptn != NULL, "node should be registered");
+    add_edge(adr_ptn, ptn);
+    return true;
+  } else if ((opcode == Op_StoreP) && adr_type->isa_rawptr()) {
+    // Stored value escapes in unsafe access.
+    Node* val = n->in(MemNode::ValueIn);
+    PointsToNode* ptn = ptnode_adr(val->_idx);
+    assert(ptn != NULL, "node should be registered");
+    set_escape_state(ptn, PointsToNode::GlobalEscape);
+    // Add edge to object for unsafe access with offset.
+    PointsToNode* adr_ptn = ptnode_adr(adr->_idx);
+    assert(adr_ptn != NULL, "node should be registered");
+    if (adr_ptn->is_Field()) {
+      assert(adr_ptn->as_Field()->is_oop(), "should be oop field");
+      add_edge(adr_ptn, ptn);
+    }
+    return true;
+  }
+  return false;
+}
+
 void ConnectionGraph::add_call_node(CallNode* call) {
   assert(call->returns_pointer(), "only for call which returns pointer");
   uint call_idx = call->_idx;
@@ -2100,7 +2072,8 @@
         // Check for unsafe oop field access
         if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
             n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
-            n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) {
+            n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN) ||
+            BarrierSet::barrier_set()->barrier_set_c2()->escape_has_out_with_unsafe_object(n)) {
           bt = T_OBJECT;
           (*unsafe) = true;
         }
@@ -2118,7 +2091,8 @@
       // Allocation initialization, ThreadLocal field access, unsafe access
       if (n->has_out_with(Op_StoreP, Op_LoadP, Op_StoreN, Op_LoadN) ||
           n->has_out_with(Op_GetAndSetP, Op_GetAndSetN, Op_CompareAndExchangeP, Op_CompareAndExchangeN) ||
-          n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN)) {
+          n->has_out_with(Op_CompareAndSwapP, Op_CompareAndSwapN, Op_WeakCompareAndSwapP, Op_WeakCompareAndSwapN) ||
+          BarrierSet::barrier_set()->barrier_set_c2()->escape_has_out_with_unsafe_object(n)) {
         bt = T_OBJECT;
       }
     }
@@ -2359,7 +2333,8 @@
       assert(opcode == Op_ConP || opcode == Op_ThreadLocal ||
              opcode == Op_CastX2P || uncast_base->is_DecodeNarrowPtr() ||
              (uncast_base->is_Mem() && (uncast_base->bottom_type()->isa_rawptr() != NULL)) ||
-             (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()), "sanity");
+             (uncast_base->is_Proj() && uncast_base->in(0)->is_Allocate()) ||
+             BarrierSet::barrier_set()->barrier_set_c2()->escape_is_barrier_node(uncast_base), "sanity");
     }
   }
   return base;
@@ -3092,6 +3067,7 @@
                n->is_CheckCastPP() ||
                n->is_EncodeP() ||
                n->is_DecodeN() ||
+               BarrierSet::barrier_set()->barrier_set_c2()->escape_is_barrier_node(n) ||
                (n->is_ConstraintCast() && n->Opcode() == Op_CastPP)) {
       if (visited.test_set(n->_idx)) {
         assert(n->is_Phi(), "loops only through Phi's");
@@ -3162,6 +3138,7 @@
                  use->is_CheckCastPP() ||
                  use->is_EncodeNarrowPtr() ||
                  use->is_DecodeNarrowPtr() ||
+                 BarrierSet::barrier_set()->barrier_set_c2()->escape_is_barrier_node(use) ||
                  (use->is_ConstraintCast() && use->Opcode() == Op_CastPP)) {
         alloc_worklist.append_if_missing(use);
 #ifdef ASSERT
@@ -3564,3 +3541,8 @@
   }
 }
 #endif
+
+void ConnectionGraph::record_for_optimizer(Node *n) {
+  _igvn->_worklist.push(n);
+  _igvn->add_users_to_worklist(n);
+}
--- a/src/hotspot/share/opto/escape.hpp	Wed Nov 14 23:12:19 2018 -0800
+++ b/src/hotspot/share/opto/escape.hpp	Thu Nov 15 10:59:56 2018 +0100
@@ -371,8 +371,6 @@
     _nodes.at_put(n->_idx, ptn);
   }
 
-  // Utility function for nodes that load an object
-  void add_objload_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist);
   // Create PointsToNode node and add it to Connection Graph.
   void add_node_to_connection_graph(Node *n, Unique_Node_List *delayed_worklist);
 
@@ -511,24 +509,8 @@
     return is_new;
   }
 
-  // Add LocalVar node and edge if possible
-  void add_local_var_and_edge(Node* n, PointsToNode::EscapeState es, Node* to,
-                              Unique_Node_List *delayed_worklist) {
-    PointsToNode* ptn = ptnode_adr(to->_idx);
-    if (delayed_worklist != NULL) { // First iteration of CG construction
-      add_local_var(n, es);
-      if (ptn == NULL) {
-        delayed_worklist->push(n);
-        return; // Process it later.
-      }
-    } else {
-      assert(ptn != NULL, "node should be registered");
-    }
-    add_edge(ptnode_adr(n->_idx), ptn);
- }
   // Helper functions
   bool   is_oop_field(Node* n, int offset, bool* unsafe);
-  Node* get_addp_base(Node *addp);
   static Node* find_second_addp(Node* addp, Node* n);
   // offset of a field reference
   int address_offset(Node* adr, PhaseTransform *phase);
@@ -574,10 +556,7 @@
   }
 
   // Notify optimizer that a node has been modified
-  void record_for_optimizer(Node *n) {
-    _igvn->_worklist.push(n);
-    _igvn->add_users_to_worklist(n);
-  }
+  void record_for_optimizer(Node *n);
 
   // Compute the escape information
   bool compute_escape();
@@ -593,6 +572,31 @@
 
   bool not_global_escape(Node *n);
 
+  // To be used by, e.g., BarrierSetC2 impls
+  Node* get_addp_base(Node* addp);
+
+  // Utility function for nodes that load an object
+  void add_objload_to_connection_graph(Node* n, Unique_Node_List* delayed_worklist);
+
+  // Add LocalVar node and edge if possible
+  void add_local_var_and_edge(Node* n, PointsToNode::EscapeState es, Node* to,
+                              Unique_Node_List *delayed_worklist) {
+    PointsToNode* ptn = ptnode_adr(to->_idx);
+    if (delayed_worklist != NULL) { // First iteration of CG construction
+      add_local_var(n, es);
+      if (ptn == NULL) {
+        delayed_worklist->push(n);
+        return; // Process it later.
+      }
+    } else {
+      assert(ptn != NULL, "node should be registered");
+    }
+    add_edge(ptnode_adr(n->_idx), ptn);
+  }
+
+  void add_to_congraph_unsafe_access(Node* n, uint opcode, Unique_Node_List* delayed_worklist);
+  bool add_final_edges_unsafe_access(Node* n, uint opcode);
+
 #ifndef PRODUCT
   void dump(GrowableArray<PointsToNode*>& ptnodes_worklist);
 #endif