Make Sema::ReferencedSelectors lazily deserialized.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@136357 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Sema/ExternalSemaSource.h

@@ -125,7 +125,17 @@ public:
   /// to introduce the same declarations repeatedly.
   virtual void ReadLocallyScopedExternalDecls(
                  SmallVectorImpl<NamedDecl *> &Decls) {}
-  
+
+  /// \brief Read the set of referenced selectors known to the
+  /// external Sema source.
+  ///
+  /// The external source should append its own referenced selectors to the 
+  /// given vector of declarations. Note that this routine 
+  /// may be invoked multiple times; the external source should take care not 
+  /// to introduce the same selectors repeatedly.
+  virtual void ReadReferencedSelectors(
+                 SmallVectorImpl<std::pair<Selector, SourceLocation> > &Sels) {}
+
   // isa/cast/dyn_cast support
   static bool classof(const ExternalASTSource *Source) {
     return Source->SemaSource;

include/clang/Serialization/ASTReader.h

@@ -1391,6 +1391,9 @@ public:
   virtual void ReadLocallyScopedExternalDecls(
                  SmallVectorImpl<NamedDecl *> &Decls);
   
+  virtual void ReadReferencedSelectors(
+                 SmallVectorImpl<std::pair<Selector, SourceLocation> > &Sels);
+
   /// \brief Load a selector from disk, registering its ID if it exists.
   void LoadSelector(Selector Sel);
 

lib/Sema/SemaDeclObjC.cpp

@@ -2765,6 +2765,14 @@ void Sema::CollectIvarsToConstructOrDestruct(ObjCInterfaceDecl *OI,
 }
 
 void Sema::DiagnoseUseOfUnimplementedSelectors() {
+  // Load referenced selectors from the external source.
+  if (ExternalSource) {
+    SmallVector<std::pair<Selector, SourceLocation>, 4> Sels;
+    ExternalSource->ReadReferencedSelectors(Sels);
+    for (unsigned I = 0, N = Sels.size(); I != N; ++I)
+      ReferencedSelectors[Sels[I].first] = Sels[I].second;
+  }
+  
   // Warning will be issued only when selector table is
   // generated (which means there is at lease one implementation
   // in the TU). This is to match gcc's behavior.

lib/Serialization/ASTReader.cpp

@@ -4366,19 +4366,6 @@ void ASTReader::InitializeSema(Sema &S) {
       SemaObj->StdBadAlloc = SemaDeclRefs[1];
   }
 
-  // If there are @selector references added them to its pool. This is for
-  // implementation of -Wselector.
-  if (!ReferencedSelectorsData.empty()) {
-    unsigned int DataSize = ReferencedSelectorsData.size()-1;
-    unsigned I = 0;
-    while (I < DataSize) {
-      Selector Sel = DecodeSelector(ReferencedSelectorsData[I++]);
-      SourceLocation SelLoc
-        = SourceLocation::getFromRawEncoding(ReferencedSelectorsData[I++]);
-      SemaObj->ReferencedSelectors.insert(std::make_pair(Sel, SelLoc));
-    }
-  }
-
   // The special data sets below always come from the most recent PCH,
   // which is at the front of the chain.
   Module &F = ModuleMgr.getPrimaryModule();
@@ -4617,6 +4604,24 @@ ASTReader::ReadLocallyScopedExternalDecls(SmallVectorImpl<NamedDecl *> &Decls) {
   LocallyScopedExternalDecls.clear();
 }
 
+void ASTReader::ReadReferencedSelectors(
+       SmallVectorImpl<std::pair<Selector, SourceLocation> > &Sels) {
+  if (ReferencedSelectorsData.empty())
+    return;
+  
+  // If there are @selector references added them to its pool. This is for
+  // implementation of -Wselector.
+  unsigned int DataSize = ReferencedSelectorsData.size()-1;
+  unsigned I = 0;
+  while (I < DataSize) {
+    Selector Sel = DecodeSelector(ReferencedSelectorsData[I++]);
+    SourceLocation SelLoc
+      = SourceLocation::getFromRawEncoding(ReferencedSelectorsData[I++]);
+    Sels.push_back(std::make_pair(Sel, SelLoc));
+  }
+  ReferencedSelectorsData.clear();
+}
+
 void ASTReader::LoadSelector(Selector Sel) {
   // It would be complicated to avoid reading the methods anyway. So don't.
   ReadMethodPool(Sel);