diff --git a/clang/include/clang/Parse/Action.h b/clang/include/clang/Parse/Action.h
index 576f14915d9462fb086eae5a1ec88597300eb736..16a1d46b13563e243852c86dd5410de01925a640 100644
--- a/clang/include/clang/Parse/Action.h
+++ b/clang/include/clang/Parse/Action.h
@@ -3134,14 +3134,17 @@ public:
                                           DeclPtrTy IDecl) {
   }
   
-  /// \brief Code completion for a selector identifier within an Objective-C
-  /// method declaration.
+  /// \brief Code completion for a selector identifier or argument name within
+  /// an Objective-C method declaration.
   ///
   /// \param S The scope in which this code completion occurs.
   ///
   /// \param IsInstanceMethod Whether we are parsing an instance method (or, 
   /// if false, a class method).
   ///
+  /// \param AtParameterName Whether the actual code completion point is at the
+  /// argument name.
+  ///
   /// \param ReturnType If non-NULL, the specified return type of the method
   /// being declared or defined.
   ///
@@ -3151,6 +3154,7 @@ public:
   /// \param NumSelIdents The number of identifiers provided by SelIdents.
   virtual void CodeCompleteObjCMethodDeclSelector(Scope *S, 
                                                   bool IsInstanceMethod,
+                                                  bool AtParameterName,
                                                   TypeTy *ReturnType,
                                                   IdentifierInfo **SelIdents,
                                                   unsigned NumSelIdents) { }
diff --git a/clang/lib/Parse/ParseObjc.cpp b/clang/lib/Parse/ParseObjc.cpp
index 79e432d611447a8e3f074fb9c6804ceafeaab72f..68473a551d1ab1489598d6c98acf3661b022e29b 100644
--- a/clang/lib/Parse/ParseObjc.cpp
+++ b/clang/lib/Parse/ParseObjc.cpp
@@ -856,6 +856,20 @@ Parser::DeclPtrTy Parser::ParseObjCMethodDecl(SourceLocation mLoc,
     if (getLang().ObjC2 && Tok.is(tok::kw___attribute))
       ArgInfo.ArgAttrs = ParseGNUAttributes();
 
+    // Code completion for the next piece of the selector.
+    if (Tok.is(tok::code_completion)) {
+      ConsumeCodeCompletionToken();
+      KeyIdents.push_back(SelIdent);
+      Actions.CodeCompleteObjCMethodDeclSelector(getCurScope(), 
+                                                 mType == tok::minus,
+                                                 /*AtParameterName=*/true,
+                                                 ReturnType,
+                                                 KeyIdents.data(), 
+                                                 KeyIdents.size());
+      KeyIdents.pop_back();
+      break;
+    }
+    
     if (Tok.isNot(tok::identifier)) {
       Diag(Tok, diag::err_expected_ident); // missing argument name.
       break;
@@ -873,6 +887,7 @@ Parser::DeclPtrTy Parser::ParseObjCMethodDecl(SourceLocation mLoc,
       ConsumeCodeCompletionToken();
       Actions.CodeCompleteObjCMethodDeclSelector(getCurScope(), 
                                                  mType == tok::minus,
+                                                 /*AtParameterName=*/false,
                                                  ReturnType,
                                                  KeyIdents.data(), 
                                                  KeyIdents.size());
diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index f4f873df2f3d27c330e63a5deae3072dcdf1f7b3..1f948b6624371ec67063a92f0d64729ada9fbcfb 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -4574,6 +4574,7 @@ public:
                                           DeclPtrTy IDecl);
   virtual void CodeCompleteObjCMethodDeclSelector(Scope *S, 
                                                   bool IsInstanceMethod,
+                                                  bool AtParameterName,
                                                   TypeTy *ReturnType,
                                                   IdentifierInfo **SelIdents,
                                                   unsigned NumSelIdents);
diff --git a/clang/lib/Sema/SemaCodeComplete.cpp b/clang/lib/Sema/SemaCodeComplete.cpp
index 8df9eace276d1e041a7160c24c1274be630ec0fe..6a706dfefe59a9dd76a5c8b805d54f4259547fae 100644
--- a/clang/lib/Sema/SemaCodeComplete.cpp
+++ b/clang/lib/Sema/SemaCodeComplete.cpp
@@ -4147,6 +4147,7 @@ void Sema::CodeCompleteObjCMethodDecl(Scope *S,
 
 void Sema::CodeCompleteObjCMethodDeclSelector(Scope *S, 
                                               bool IsInstanceMethod,
+                                              bool AtParameterName,
                                               TypeTy *ReturnTy,
                                               IdentifierInfo **SelIdents,
                                               unsigned NumSelIdents) {
@@ -4185,6 +4186,20 @@ void Sema::CodeCompleteObjCMethodDeclSelector(Scope *S,
                                   NumSelIdents))
         continue;
       
+      if (AtParameterName) {
+        // Suggest parameter names we've seen before.
+        if (NumSelIdents && NumSelIdents <= MethList->Method->param_size()) {
+          ParmVarDecl *Param = MethList->Method->param_begin()[NumSelIdents-1];
+          if (Param->getIdentifier()) {
+            CodeCompletionString *Pattern = new CodeCompletionString;
+            Pattern->AddTypedTextChunk(Param->getIdentifier()->getName());
+            Results.AddResult(Pattern);
+          }
+        }
+        
+        continue;
+      }
+      
       Result R(MethList->Method, 0);
       R.StartParameter = NumSelIdents;
       R.AllParametersAreInformative = false;
diff --git a/clang/test/Index/complete-method-decls.m b/clang/test/Index/complete-method-decls.m
index 802b360f0049ae8b2eeaeda5201764356feb54fd..a30874b8a28e24b35aa3f58377c55879e03ba809 100644
--- a/clang/test/Index/complete-method-decls.m
+++ b/clang/test/Index/complete-method-decls.m
@@ -44,12 +44,12 @@
 
 @interface C
 - (int)first:(int)x second:(float)y third:(double)z;
-- (id)first:(int)x second2:(float)y third:(double)z;
-- (void*)first:(int)x second3:(float)y third:(double)z;
+- (id)first:(int)xx second2:(float)y2 third:(double)z;
+- (void*)first:(int)xxx second3:(float)y3 third:(double)z;
 @end
 
 @interface D
-- (int)first:(int)x second4:(float)y third:(double)z;
+- (int)first:(int)x second2:(float)y third:(double)z;
 @end
 
 // RUN: c-index-test -code-completion-at=%s:17:3 %s | FileCheck -check-prefix=CHECK-CC1 %s
@@ -90,8 +90,14 @@
 // RUN: c-index-test -code-completion-at=%s:42:3 -Xclang -code-completion-patterns %s | FileCheck -check-prefix=CHECK-CC7 %s
 // CHECK-CC7: NotImplemented:{LeftParen (}{Text id}{RightParen )}{TypedText categoryFunction}{Colon :}{LeftParen (}{Text int}{RightParen )}{Text x}{HorizontalSpace  }{LeftBrace {}{VerticalSpace 
 // RUN: c-index-test -code-completion-at=%s:52:21 -Xclang -code-completion-patterns %s | FileCheck -check-prefix=CHECK-CC8 %s
-// CHECK-CC8: ObjCInstanceMethodDecl:{ResultType id}{Informative first:}{TypedText second2:}{Text (float)y}{HorizontalSpace  }{Text third:}{Text (double)z} (20)
-// CHECK-CC8: ObjCInstanceMethodDecl:{ResultType void *}{Informative first:}{TypedText second3:}{Text (float)y}{HorizontalSpace  }{Text third:}{Text (double)z} (20)
+// CHECK-CC8: ObjCInstanceMethodDecl:{ResultType id}{Informative first:}{TypedText second2:}{Text (float)y2}{HorizontalSpace  }{Text third:}{Text (double)z} (20)
+// CHECK-CC8: ObjCInstanceMethodDecl:{ResultType void *}{Informative first:}{TypedText second3:}{Text (float)y3}{HorizontalSpace  }{Text third:}{Text (double)z} (20)
 // CHECK-CC8: ObjCInstanceMethodDecl:{ResultType int}{Informative first:}{TypedText second:}{Text (float)y}{HorizontalSpace  }{Text third:}{Text (double)z} (5)
+// RUN: c-index-test -code-completion-at=%s:52:19 -Xclang -code-completion-patterns %s | FileCheck -check-prefix=CHECK-CC9 %s
+// CHECK-CC9: NotImplemented:{TypedText x} (30)
+// CHECK-CC9: NotImplemented:{TypedText xx} (30)
+// CHECK-CC9: NotImplemented:{TypedText xxx} (30)
+// RUN: c-index-test -code-completion-at=%s:52:36 -Xclang -code-completion-patterns %s | FileCheck -check-prefix=CHECK-CCA %s
+// CHECK-CCA: NotImplemented:{TypedText y2} (30)