Update clang to 91430.

1 files changed, 49 insertions, 4 deletions

diff --git a/include/clang/AST/DeclContextInternals.h b/include/clang/AST/DeclContextInternals.h
index c2b48ce..32405ee 100644
--- a/include/clang/AST/DeclContextInternals.h
+++ b/include/clang/AST/DeclContextInternals.h
@@ -131,6 +131,25 @@ public:
     return DK == DK_DeclID || DK == DK_ID_Vector;
   }
 
+  void remove(NamedDecl *D) {
+    assert(!isNull() && "removing from empty list");
+    if (NamedDecl *Singleton = getAsDecl()) {
+      assert(Singleton == D && "list is different singleton");
+      (void)Singleton;
+      Data = 0;
+      return;
+    }
+
+    VectorTy &Vec = *getAsVector();
+    VectorTy::iterator I = std::find(Vec.begin(), Vec.end(),
+                                     reinterpret_cast<uintptr_t>(D));
+    assert(I != Vec.end() && "list does not contain decl");
+    Vec.erase(I);
+
+    assert(std::find(Vec.begin(), Vec.end(), reinterpret_cast<uintptr_t>(D))
+             == Vec.end() && "list still contains decl");
+  }
+
   /// getLookupResult - Return an array of all the decls that this list
   /// represents.
   DeclContext::lookup_result getLookupResult(ASTContext &Context) {
@@ -200,11 +219,37 @@ public:
     }
 
     VectorTy &Vec = *getAsVector();
-    if (isa<UsingDirectiveDecl>(D) ||
-        D->getIdentifierNamespace() == Decl::IDNS_Tag)
+
+    // Using directives end up in a special entry which contains only
+    // other using directives, so all this logic is wasted for them.
+    // But avoiding the logic wastes time in the far-more-common case
+    // that we're *not* adding a new using directive.
+
+    // Tag declarations always go at the end of the list so that an
+    // iterator which points at the first tag will start a span of
+    // decls that only contains tags.
+    if (D->getIdentifierNamespace() == Decl::IDNS_Tag)
       Vec.push_back(reinterpret_cast<uintptr_t>(D));
-    else if (reinterpret_cast<NamedDecl *>(Vec.back())
-               ->getIdentifierNamespace() == Decl::IDNS_Tag) {
+
+    // Resolved using declarations go at the front of the list so that
+    // they won't show up in other lookup results.  Unresolved using
+    // declarations (which are always in IDNS_Using | IDNS_Ordinary)
+    // follow that so that the using declarations will be contiguous.
+    else if (D->getIdentifierNamespace() & Decl::IDNS_Using) {
+      VectorTy::iterator I = Vec.begin();
+      if (D->getIdentifierNamespace() != Decl::IDNS_Using) {
+        while (I != Vec.end() &&
+               reinterpret_cast<NamedDecl *>(*I)
+                 ->getIdentifierNamespace() == Decl::IDNS_Using)
+          ++I;
+      }
+      Vec.insert(I, reinterpret_cast<uintptr_t>(D));
+
+    // All other declarations go at the end of the list, but before any
+    // tag declarations.  But we can be clever about tag declarations
+    // because there can only ever be one in a scope.
+    } else if (reinterpret_cast<NamedDecl *>(Vec.back())
+                 ->getIdentifierNamespace() == Decl::IDNS_Tag) {
       uintptr_t TagD = Vec.back();
       Vec.back() = reinterpret_cast<uintptr_t>(D);
       Vec.push_back(TagD);