Address review feedback on r221933.

Remove ObjCMethodList::Count, instead store a "has more than one decl" bit in
the low bit of the ObjCMethodDecl pointer, using a PointerIntPair.

Most of this patch is replacing ".Method" with ".getMethod()".

No intended behavior change.

llvm-svn: 224876

1 files changed, 62 insertions, 56 deletions

diff --git a/clang/lib/Sema/SemaDeclObjC.cpp b/clang/lib/Sema/SemaDeclObjC.cpp
index eccf2e1d2ae..90835be722b 100644
--- a/clang/lib/Sema/SemaDeclObjC.cpp
+++ b/clang/lib/Sema/SemaDeclObjC.cpp
@@ -2004,13 +2004,12 @@ void Sema::ImplMethodsVsClassMethods(Scope *S, ObjCImplDecl* IMPDecl,
                                 IncompleteImpl, InsMap, ClsMap, CDecl,
                                 ExplicitImplProtocols);
       DiagnoseUnimplementedProperties(S, IMPDecl, CDecl,
-                                      /* SynthesizeProperties */ false);
+                                      /*SynthesizeProperties=*/false);
     } 
   } else
     llvm_unreachable("invalid ObjCContainerDecl type.");
 }
 
-/// ActOnForwardClassDeclaration -
 Sema::DeclGroupPtrTy
 Sema::ActOnForwardClassDeclaration(SourceLocation AtClassLoc,
                                    IdentifierInfo **IdentList,
@@ -2037,10 +2036,11 @@ Sema::ActOnForwardClassDeclaration(SourceLocation AtClassLoc,
       } else {
         // a forward class declaration matching a typedef name of a class refers
         // to the underlying class. Just ignore the forward class with a warning
-        // as this will force the intended behavior which is to lookup the typedef
-        // name.
+        // as this will force the intended behavior which is to lookup the
+        // typedef name.
         if (isa<ObjCObjectType>(TDD->getUnderlyingType())) {
-          Diag(AtClassLoc, diag::warn_forward_class_redefinition) << IdentList[i];
+          Diag(AtClassLoc, diag::warn_forward_class_redefinition)
+              << IdentList[i];
           Diag(PrevDecl->getLocation(), diag::note_previous_definition);
           continue;
         }
@@ -2217,22 +2217,22 @@ bool Sema::MatchTwoMethodDeclarations(const ObjCMethodDecl *left,
   return true;
 }
 
-void Sema::addMethodToGlobalList(ObjCMethodList *List, ObjCMethodDecl *Method) {
+void Sema::addMethodToGlobalList(ObjCMethodList *List,
+                                 ObjCMethodDecl *Method) {
   // Record at the head of the list whether there were 0, 1, or >= 2 methods
   // inside categories.
-  if (ObjCCategoryDecl *
-        CD = dyn_cast<ObjCCategoryDecl>(Method->getDeclContext()))
+  if (ObjCCategoryDecl *CD =
+          dyn_cast<ObjCCategoryDecl>(Method->getDeclContext()))
     if (!CD->IsClassExtension() && List->getBits() < 2)
-        List->setBits(List->getBits()+1);
+      List->setBits(List->getBits() + 1);
 
   // If the list is empty, make it a singleton list.
-  if (List->Method == nullptr) {
-    List->Method = Method;
+  if (List->getMethod() == nullptr) {
+    List->setMethod(Method);
     List->setNext(nullptr);
-      List->Count = Method->isDefined() ? 0 : 1;
     return;
   }
-  
+
   // We've seen a method with this name, see if we have already seen this type
   // signature.
   ObjCMethodList *Previous = List;
@@ -2241,37 +2241,42 @@ void Sema::addMethodToGlobalList(ObjCMethodList *List, ObjCMethodDecl *Method) {
     if (getLangOpts().Modules && !getLangOpts().CurrentModule.empty())
       continue;
 
-    if (!MatchTwoMethodDeclarations(Method, List->Method))
+    if (!MatchTwoMethodDeclarations(Method, List->getMethod()))
       continue;
-      
-    ObjCMethodDecl *PrevObjCMethod = List->Method;
+
+    ObjCMethodDecl *PrevObjCMethod = List->getMethod();
 
     // Propagate the 'defined' bit.
     if (Method->isDefined())
       PrevObjCMethod->setDefined(true);
-    else
-      ++List->Count;
-    
+    else if (!PrevObjCMethod->isDefined()) {
+      // Objective-C doesn't allow an @interface for a class after its
+      // @implementation. So if Method is not defined and there already is
+      // an entry for this type signature, Method has to be for a different
+      // class than PrevObjCMethod.
+      List->setHasMoreThanOneDecl(true);
+    }
+
     // If a method is deprecated, push it in the global pool.
     // This is used for better diagnostics.
     if (Method->isDeprecated()) {
       if (!PrevObjCMethod->isDeprecated())
-        List->Method = Method;
+        List->setMethod(Method);
     }
-    // If new method is unavailable, push it into global pool
+    // If the new method is unavailable, push it into global pool
     // unless previous one is deprecated.
     if (Method->isUnavailable()) {
       if (PrevObjCMethod->getAvailability() < AR_Deprecated)
-        List->Method = Method;
+        List->setMethod(Method);
     }
-    
+
     return;
   }
-  
+
   // We have a new signature for an existing method - add it.
   // This is extremely rare. Only 1% of Cocoa selectors are "overloaded".
   ObjCMethodList *Mem = BumpAlloc.Allocate<ObjCMethodList>();
-  Previous->setNext(new (Mem) ObjCMethodList(Method, 0, nullptr));
+  Previous->setNext(new (Mem) ObjCMethodList(Method));
 }
 
 /// \brief Read the contents of the method pool for a given selector from
@@ -2294,7 +2299,7 @@ void Sema::AddMethodToGlobalPool(ObjCMethodDecl *Method, bool impl,
   if (Pos == MethodPool.end())
     Pos = MethodPool.insert(std::make_pair(Method->getSelector(),
                                            GlobalMethods())).first;
-  
+
   Method->setDefined(impl);
   
   ObjCMethodList &Entry = instance ? Pos->second.first : Pos->second.second;
@@ -2320,9 +2325,8 @@ static bool isAcceptableMethodMismatch(ObjCMethodDecl *chosen,
   return (chosen->getReturnType()->isIntegerType());
 }
 
-bool Sema::CollectMultipleMethodsInGlobalPool(Selector Sel,
-                                              SmallVectorImpl<ObjCMethodDecl*>& Methods,
-                                              bool instance) {
+bool Sema::CollectMultipleMethodsInGlobalPool(
+    Selector Sel, SmallVectorImpl<ObjCMethodDecl *> &Methods, bool instance) {
   if (ExternalSource)
     ReadMethodPool(Sel);
 
@@ -2332,19 +2336,19 @@ bool Sema::CollectMultipleMethodsInGlobalPool(Selector Sel,
   // Gather the non-hidden methods.
   ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second;
   for (ObjCMethodList *M = &MethList; M; M = M->getNext())
-    if (M->Method && !M->Method->isHidden())
-      Methods.push_back(M->Method);
-  return (Methods.size() > 1);
+    if (M->getMethod() && !M->getMethod()->isHidden())
+      Methods.push_back(M->getMethod());
+  return Methods.size() > 1;
 }
 
-bool Sema::AreMultipleMethodsInGlobalPool(Selector Sel,
-                                          bool instance) {
+bool Sema::AreMultipleMethodsInGlobalPool(Selector Sel, bool instance) {
   GlobalMethodPool::iterator Pos = MethodPool.find(Sel);
-  // Test for no method in the pool which should not trigger any warning by caller.
+  // Test for no method in the pool which should not trigger any warning by
+  // caller.
   if (Pos == MethodPool.end())
     return true;
   ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second;
-  return MethList.Count > 1;
+  return MethList.hasMoreThanOneDecl();
 }
 
 ObjCMethodDecl *Sema::LookupMethodInGlobalPool(Selector Sel, SourceRange R,
@@ -2361,12 +2365,12 @@ ObjCMethodDecl *Sema::LookupMethodInGlobalPool(Selector Sel, SourceRange R,
   ObjCMethodList &MethList = instance ? Pos->second.first : Pos->second.second;
   SmallVector<ObjCMethodDecl *, 4> Methods;
   for (ObjCMethodList *M = &MethList; M; M = M->getNext()) {
-    if (M->Method && !M->Method->isHidden()) {
+    if (M->getMethod() && !M->getMethod()->isHidden()) {
       // If we're not supposed to warn about mismatches, we're done.
       if (!warn)
-        return M->Method;
+        return M->getMethod();
 
-      Methods.push_back(M->Method);
+      Methods.push_back(M->getMethod());
     }
   }
 
@@ -2438,13 +2442,13 @@ ObjCMethodDecl *Sema::LookupImplementedMethodInGlobalPool(Selector Sel) {
   GlobalMethods &Methods = Pos->second;
   for (const ObjCMethodList *Method = &Methods.first; Method;
        Method = Method->getNext())
-    if (Method->Method && Method->Method->isDefined())
-      return Method->Method;
+    if (Method->getMethod() && Method->getMethod()->isDefined())
+      return Method->getMethod();
   
   for (const ObjCMethodList *Method = &Methods.second; Method;
        Method = Method->getNext())
-    if (Method->Method && Method->Method->isDefined())
-      return Method->Method;
+    if (Method->getMethod() && Method->getMethod()->isDefined())
+      return Method->getMethod();
   return nullptr;
 }
 
@@ -2507,25 +2511,27 @@ Sema::SelectorsForTypoCorrection(Selector Sel,
        e = MethodPool.end(); b != e; b++) {
     // instance methods
     for (ObjCMethodList *M = &b->second.first; M; M=M->getNext())
-      if (M->Method &&
-          (M->Method->getSelector().getNumArgs() == NumArgs) &&
-          (M->Method->getSelector() != Sel)) {
+      if (M->getMethod() &&
+          (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
+          (M->getMethod()->getSelector() != Sel)) {
         if (ObjectIsId)
-          Methods.push_back(M->Method);
+          Methods.push_back(M->getMethod());
         else if (!ObjectIsClass &&
-                 HelperIsMethodInObjCType(*this, M->Method->getSelector(), ObjectType))
-          Methods.push_back(M->Method);
+                 HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
+                                          ObjectType))
+          Methods.push_back(M->getMethod());
       }
     // class methods
     for (ObjCMethodList *M = &b->second.second; M; M=M->getNext())
-      if (M->Method &&
-          (M->Method->getSelector().getNumArgs() == NumArgs) &&
-          (M->Method->getSelector() != Sel)) {
+      if (M->getMethod() &&
+          (M->getMethod()->getSelector().getNumArgs() == NumArgs) &&
+          (M->getMethod()->getSelector() != Sel)) {
         if (ObjectIsClass)
-          Methods.push_back(M->Method);
+          Methods.push_back(M->getMethod());
         else if (!ObjectIsId &&
-                 HelperIsMethodInObjCType(*this, M->Method->getSelector(), ObjectType))
-          Methods.push_back(M->Method);
+                 HelperIsMethodInObjCType(*this, M->getMethod()->getSelector(),
+                                          ObjectType))
+          Methods.push_back(M->getMethod());
       }
   }
   
@@ -2855,7 +2861,7 @@ public:
     }
     ObjCMethodList &list =
       method->isInstanceMethod() ? it->second.first : it->second.second;
-    if (!list.Method) return;
+    if (!list.getMethod()) return;
 
     ObjCContainerDecl *container
       = cast<ObjCContainerDecl>(method->getDeclContext());