[analyzer] Implement an opt-in variant of direct ivar assignment.

This will only check the direct ivar assignments in the annotated
methods.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169349 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/Checkers.td b/lib/StaticAnalyzer/Checkers/Checkers.td
index 235e633..10881b3 100644
--- a/lib/StaticAnalyzer/Checkers/Checkers.td
+++ b/lib/StaticAnalyzer/Checkers/Checkers.td
@@ -417,7 +417,11 @@
   DescFile<"IvarInvalidationChecker.cpp">;
 
 def DirectIvarAssignment : Checker<"DirectIvarAssignment">,
-  HelpText<"Check that the invalidatable instance variables are invalidated in the methods annotated with objc_instance_variable_invalidator">,
+  HelpText<"Check for direct assignments to instance variables">,
+  DescFile<"DirectIvarAssignment.cpp">;
+
+def DirectIvarAssignmentForAnnotatedFunctions : Checker<"DirectIvarAssignmentForAnnotatedFunctions">,
+  HelpText<"Check for direct assignments to instance variables in the methods annotated with objc_no_direct_instance_variable_assignmemt">,
   DescFile<"DirectIvarAssignment.cpp">;
 
 def ObjCSuperCallChecker : Checker<"MissingSuperCall">,