Rework the traversal of Objective-C categories and extensions to

consider (sub)module visibility.

The bulk of this change replaces myriad hand-rolled loops over the
linked list of Objective-C categories/extensions attached to an
interface declaration with loops using one of the four new category
iterator kinds:

  visible_categories_iterator: Iterates over all visible categories
  and extensions, hiding any that have their "hidden" bit set. This is
  by far the most commonly used iterator.

  known_categories_iterator: Iterates over all categories and
  extensions, ignoring the "hidden" bit. This tends to be used for
  redeclaration-like traversals.

  visible_extensions_iterator: Iterates over all visible extensions,
  hiding any that have their "hidden" bit set.

  known_extensions_iterator: Iterates over all extensions, whether
  they are visible to normal name lookup or not.

The effect of this change is that any uses of the visible_ iterators
will respect module-import visibility. See the new tests for examples.

Note that the old accessors for categories and extensions are gone;
there are *Raw() forms for some of them, for those (few) areas of the
compiler that have to manipulate the linked list of categories
directly. This is generally discouraged.

Part two of <rdar://problem/10634711>.
 



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172665 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 9 deletions

diff --git a/lib/AST/DumpXML.cpp b/lib/AST/DumpXML.cpp
index 1e7523f3b9..be22ae450b 100644
--- a/lib/AST/DumpXML.cpp
+++ b/lib/AST/DumpXML.cpp
@@ -748,14 +748,6 @@ struct XMLDumper : public XMLDeclVisitor<XMLDumper>,
     visitDeclContext(D);
   }
 
-  // ObjCInterfaceDecl
-  void visitCategoryList(ObjCCategoryDecl *D) {
-    if (!D) return;
-
-    TemporaryContainer C(*this, "categories");
-    for (; D; D = D->getNextClassCategory())
-      visitDeclRef(D);
-  }
   void visitObjCInterfaceDeclAttrs(ObjCInterfaceDecl *D) {
     setPointer("typeptr", D->getTypeForDecl());
     setFlag("forward_decl", !D->isThisDeclarationADefinition());
@@ -770,7 +762,17 @@ struct XMLDumper : public XMLDeclVisitor<XMLDumper>,
              I = D->protocol_begin(), E = D->protocol_end(); I != E; ++I)
         visitDeclRef(*I);
     }
-    visitCategoryList(D->getCategoryList());
+
+    if (!D->visible_categories_empty()) {
+      TemporaryContainer C(*this, "categories");
+
+      for (ObjCInterfaceDecl::visible_categories_iterator
+               Cat = D->visible_categories_begin(),
+             CatEnd = D->visible_categories_end();
+           Cat != CatEnd; ++Cat) {
+        visitDeclRef(*Cat);
+      }
+    }
   }
   void visitObjCInterfaceDeclAsContext(ObjCInterfaceDecl *D) {
     visitDeclContext(D);