4 files changed, 50 insertions, 11 deletions

diff --git a/gcc/rust/hir/rust-ast-lower-item.h b/gcc/rust/hir/rust-ast-lower-item.h
index edbc498..18ead3c 100644
--- a/gcc/rust/hir/rust-ast-lower-item.h
+++ b/gcc/rust/hir/rust-ast-lower-item.h
@@ -360,12 +360,14 @@ public:
 				   mappings->get_next_localdef_id (crate_num));
 
     std::vector<std::unique_ptr<HIR::InherentImplItem> > impl_items;
+    std::vector<HirId> impl_item_ids;
     for (auto &impl_item : impl_block.get_impl_items ())
       {
 	HIR::InherentImplItem *lowered
 	  = ASTLowerImplItem::translate (impl_item.get (),
 					 mapping.get_hirid ());
 	impl_items.push_back (std::unique_ptr<HIR::InherentImplItem> (lowered));
+	impl_item_ids.push_back (lowered->get_impl_mappings ().get_hirid ());
       }
 
     translated
@@ -381,6 +383,13 @@ public:
 			       translated);
     mappings->insert_location (crate_num, mapping.get_hirid (),
 			       impl_block.get_locus ());
+
+    for (auto &impl_item_id : impl_item_ids)
+      {
+	mappings->insert_impl_item_mapping (impl_item_id,
+					    static_cast<HIR::InherentImpl *> (
+					      translated));
+      }
   }
 
 private:
diff --git a/gcc/rust/hir/tree/rust-hir-path.h b/gcc/rust/hir/tree/rust-hir-path.h
index 8dbde9c..d6f9fc0 100644
--- a/gcc/rust/hir/tree/rust-hir-path.h
+++ b/gcc/rust/hir/tree/rust-hir-path.h
@@ -255,6 +255,12 @@ public:
       }
   }
 
+  size_t get_num_segments () const { return segments.size (); }
+
+  std::vector<PathExprSegment> &get_segments () { return segments; }
+
+  PathExprSegment &get_root_seg () { return segments.at (0); }
+
   PathExprSegment get_final_segment () const { return segments.back (); }
 };
 
diff --git a/gcc/rust/util/rust-hir-map.cc b/gcc/rust/util/rust-hir-map.cc
index 891618e..0dcbd4f 100644
--- a/gcc/rust/util/rust-hir-map.cc
+++ b/gcc/rust/util/rust-hir-map.cc
@@ -524,5 +524,24 @@ Mappings::resolve_nodeid_to_stmt (CrateNum crate, NodeId id, HIR::Stmt **stmt)
   return resolved_stmt != nullptr;
 }
 
+void
+Mappings::iterate_impl_items (
+  std::function<bool (HirId, HIR::InherentImplItem *, HIR::InherentImpl *)> cb)
+{
+  for (auto it = hirImplItemMappings.begin (); it != hirImplItemMappings.end ();
+       it++)
+    {
+      for (auto iy = it->second.begin (); iy != it->second.end (); iy++)
+	{
+	  auto id = iy->first;
+	  auto impl_item = iy->second.second;
+	  auto impl = lookup_associated_impl (
+	    impl_item->get_impl_mappings ().get_hirid ());
+	  if (!cb (id, impl_item, impl))
+	    return;
+	}
+    }
+}
+
 } // namespace Analysis
 } // namespace Rust
diff --git a/gcc/rust/util/rust-hir-map.h b/gcc/rust/util/rust-hir-map.h
index 2e8a629..9777ee3 100644
--- a/gcc/rust/util/rust-hir-map.h
+++ b/gcc/rust/util/rust-hir-map.h
@@ -158,20 +158,24 @@ public:
     return hirNodesWithinCrate[crate];
   }
 
-  void
-  iterate_impl_items (std::function<bool (HirId, HIR::InherentImplItem *)> cb)
+  void insert_impl_item_mapping (HirId impl_item_id, HIR::InherentImpl *impl)
   {
-    for (auto it = hirImplItemMappings.begin ();
-	 it != hirImplItemMappings.end (); it++)
-      {
-	for (auto iy = it->second.begin (); iy != it->second.end (); iy++)
-	  {
-	    if (!cb (iy->first, iy->second.second))
-	      return;
-	  }
-      }
+    rust_assert (hirImplItemsToImplMappings.find (impl_item_id)
+		 == hirImplItemsToImplMappings.end ());
+    hirImplItemsToImplMappings[impl_item_id] = impl;
   }
 
+  HIR::InherentImpl *lookup_associated_impl (HirId impl_item_id)
+  {
+    auto lookup = hirImplItemsToImplMappings.find (impl_item_id);
+    rust_assert (lookup != hirImplItemsToImplMappings.end ());
+    return lookup->second;
+  }
+
+  void iterate_impl_items (
+    std::function<bool (HirId, HIR::InherentImplItem *, HIR::InherentImpl *)>
+      cb);
+
 private:
   Mappings ();
 
@@ -198,6 +202,7 @@ private:
 	   std::map<HirId, std::pair<HirId, HIR::InherentImplItem *> > >
     hirImplItemMappings;
   std::map<CrateNum, std::map<HirId, HIR::SelfParam *> > hirSelfParamMappings;
+  std::map<HirId, HIR::InherentImpl *> hirImplItemsToImplMappings;
 
   // location info
   std::map<CrateNum, std::map<NodeId, Location> > locations;