# HG changeset patch
# User rkennke
# Date 1542797259 -3600
#      Wed Nov 21 11:47:39 2018 +0100
# Node ID d21d2ad9492725a2fafbfdc04f6f850e828bf89a
# Parent  f94ac11610b3fc25afc4a9fdfb7df8cf697a766a
8214055: GC/C2 abstraction for phaseX

diff --git a/src/hotspot/share/gc/shared/c2/barrierSetC2.hpp b/src/hotspot/share/gc/shared/c2/barrierSetC2.hpp
--- a/src/hotspot/share/gc/shared/c2/barrierSetC2.hpp
+++ b/src/hotspot/share/gc/shared/c2/barrierSetC2.hpp
@@ -262,7 +262,6 @@
   virtual void clone_barrier_at_expansion(ArrayCopyNode* ac, Node* call, PhaseIterGVN& igvn) const;
 
   // Support for GC barriers emitted during parsing
-  virtual bool has_load_barriers() const { return false; }
   virtual bool is_gc_barrier_node(Node* node) const { return false; }
   virtual Node* step_over_gc_barrier(Node* c) const { return c; }
 
@@ -303,6 +302,10 @@
   virtual bool matcher_find_shared_visit(Matcher* matcher, Matcher::MStack& mstack, Node* n, uint opcode, bool& mem_op, int& mem_addr_idx) const { return false; };
   virtual bool matcher_find_shared_post_visit(Matcher* matcher, Node* n, uint opcode) const { return false; };
   virtual bool matcher_is_store_load_barrier(Node* x, uint xop) const { return false; }
+
+  virtual void igvn_add_users_to_worklist(PhaseIterGVN* igvn, Node* use) const {}
+  virtual void ccp_analyze(PhaseCCP* ccp, Unique_Node_List& worklist, Node* use) const {}
+
 };
 
 #endif // SHARE_GC_SHARED_C2_BARRIERSETC2_HPP
diff --git a/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp b/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp
--- a/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp
+++ b/src/hotspot/share/gc/z/c2/zBarrierSetC2.cpp
@@ -1623,4 +1623,47 @@
       break;
   }
   return false;
-}
\ No newline at end of file
+}
+
+void ZBarrierSetC2::igvn_add_users_to_worklist(PhaseIterGVN* igvn, Node* use) const {
+  // Loading the java mirror from a Klass requires two loads and the type
+  // of the mirror load depends on the type of 'n'. See LoadNode::Value().
+  //   LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
+  int use_op = use->Opcode();
+  if (use_op == Op_LoadP && use->bottom_type()->isa_rawptr()) {
+    for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
+      Node* u = use->fast_out(i2);
+      const Type* ut = u->bottom_type();
+      if (u->Opcode() == Op_LoadP && ut->isa_instptr()) {
+        // Search for load barriers behind the load
+        for (DUIterator_Fast i3max, i3 = u->fast_outs(i3max); i3 < i3max; i3++) {
+          Node* b = u->fast_out(i3);
+          if (is_gc_barrier_node(b)) {
+            igvn->_worklist.push(b);
+          }
+        }
+      }
+    }
+  }
+}
+
+void ZBarrierSetC2::ccp_analyze(PhaseCCP* ccp, Unique_Node_List& worklist, Node* use) const {
+  // Loading the java mirror from a Klass requires two loads and the type
+  // of the mirror load depends on the type of 'n'. See LoadNode::Value().
+  int use_op = use->Opcode();
+  if (use_op == Op_LoadP && use->bottom_type()->isa_rawptr()) {
+    for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
+      Node* u = use->fast_out(i2);
+      const Type* ut = u->bottom_type();
+      if (u->Opcode() == Op_LoadP && ut->isa_instptr() && ut != ccp->type(u)) {
+        // Search for load barriers behind the load
+        for (DUIterator_Fast i3max, i3 = u->fast_outs(i3max); i3 < i3max; i3++) {
+           Node* b = u->fast_out(i3);
+          if (is_gc_barrier_node(b)) {
+            worklist.push(b);
+          }
+        }
+      }
+    }
+  }
+}
diff --git a/src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp b/src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp
--- a/src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp
+++ b/src/hotspot/share/gc/z/c2/zBarrierSetC2.hpp
@@ -190,7 +190,6 @@
                      bool oop_reload_allowed = true) const;
 
   virtual void* create_barrier_state(Arena* comp_arena) const;
-  virtual bool has_load_barriers() const { return true; }
   virtual bool is_gc_barrier_node(Node* node) const;
   virtual void eliminate_gc_barrier(PhaseMacroExpand* macro, Node* node) const { }
   virtual void eliminate_useless_gc_barriers(Unique_Node_List &useful, Compile* C) const;
@@ -218,6 +217,9 @@
   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;
 
+  virtual void igvn_add_users_to_worklist(PhaseIterGVN* igvn, Node* use) const;
+  virtual void ccp_analyze(PhaseCCP* ccp, Unique_Node_List& worklist, Node* use) const;
+
 };
 
 #endif // SHARE_GC_Z_C2_ZBARRIERSETC2_HPP
diff --git a/src/hotspot/share/opto/phaseX.cpp b/src/hotspot/share/opto/phaseX.cpp
--- a/src/hotspot/share/opto/phaseX.cpp
+++ b/src/hotspot/share/opto/phaseX.cpp
@@ -1655,28 +1655,17 @@
     }
     // Loading the java mirror from a Klass requires two loads and the type
     // of the mirror load depends on the type of 'n'. See LoadNode::Value().
-    //   LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
-    BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
-    bool has_load_barriers = bs->has_load_barriers();
-
     if (use_op == Op_LoadP && use->bottom_type()->isa_rawptr()) {
       for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
         Node* u = use->fast_out(i2);
         const Type* ut = u->bottom_type();
         if (u->Opcode() == Op_LoadP && ut->isa_instptr()) {
-          if (has_load_barriers) {
-            // Search for load barriers behind the load
-            for (DUIterator_Fast i3max, i3 = u->fast_outs(i3max); i3 < i3max; i3++) {
-              Node* b = u->fast_out(i3);
-              if (bs->is_gc_barrier_node(b)) {
-                _worklist.push(b);
-              }
-            }
-          }
           _worklist.push(u);
         }
       }
     }
+
+    BarrierSet::barrier_set()->barrier_set_c2()->igvn_add_users_to_worklist(this, use);
   }
 }
 
@@ -1814,27 +1803,17 @@
         }
         // Loading the java mirror from a Klass requires two loads and the type
         // of the mirror load depends on the type of 'n'. See LoadNode::Value().
-        BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
-        bool has_load_barriers = bs->has_load_barriers();
-
         if (m_op == Op_LoadP && m->bottom_type()->isa_rawptr()) {
           for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
             Node* u = m->fast_out(i2);
             const Type* ut = u->bottom_type();
             if (u->Opcode() == Op_LoadP && ut->isa_instptr() && ut != type(u)) {
-              if (has_load_barriers) {
-                // Search for load barriers behind the load
-                for (DUIterator_Fast i3max, i3 = u->fast_outs(i3max); i3 < i3max; i3++) {
-                  Node* b = u->fast_out(i3);
-                  if (bs->is_gc_barrier_node(b)) {
-                    _worklist.push(b);
-                  }
-                }
-              }
               worklist.push(u);
             }
           }
         }
+
+        BarrierSet::barrier_set()->barrier_set_c2()->ccp_analyze(this, worklist, m);
       }
     }
   }