When deserializing a declaration, don't look for redeclarations if its

kind indicates that it can never be redeclared. Good for a 1% speedup,
and redeclaration searching drops off the profile.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173054 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 14 deletions

diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 146065866b..4ae67a04e7 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -116,29 +116,25 @@ namespace clang {
       ASTReader &Reader;
       GlobalDeclID FirstID;
       mutable bool Owning;
+      Decl::Kind DeclKind;
       
       void operator=(RedeclarableResult &) LLVM_DELETED_FUNCTION;
       
     public:
-      RedeclarableResult(ASTReader &Reader, GlobalDeclID FirstID)
-        : Reader(Reader), FirstID(FirstID), Owning(true) { }
+      RedeclarableResult(ASTReader &Reader, GlobalDeclID FirstID,
+                         Decl::Kind DeclKind)
+        : Reader(Reader), FirstID(FirstID), Owning(true), DeclKind(DeclKind) { }
 
       RedeclarableResult(const RedeclarableResult &Other)
-        : Reader(Other.Reader), FirstID(Other.FirstID), Owning(Other.Owning) 
+        : Reader(Other.Reader), FirstID(Other.FirstID), Owning(Other.Owning) ,
+          DeclKind(Other.DeclKind)
       { 
         Other.Owning = false;
       }
 
       ~RedeclarableResult() {
-        // FIXME: We want to suppress this when the declaration is local to
-        // a function, since there's no reason to search other AST files
-        // for redeclarations (they can't exist). However, this is hard to 
-        // do locally because the declaration hasn't necessarily loaded its
-        // declaration context yet. Also, local externs still have the function
-        // as their (semantic) declaration context, which is wrong and would
-        // break this optimize.
-        
-        if (FirstID && Owning && Reader.PendingDeclChainsKnown.insert(FirstID))
+        if (FirstID && Owning && isRedeclarableDeclKind(DeclKind) &&
+            Reader.PendingDeclChainsKnown.insert(FirstID))
           Reader.PendingDeclChains.push_back(FirstID);
       }
       
@@ -151,7 +147,7 @@ namespace clang {
         Owning = false;
       }
     };
-    
+
     /// \brief Class used to capture the result of searching for an existing
     /// declaration of a specific kind and name, along with the ability
     /// to update the place where this result was found (the declaration
@@ -1562,7 +1558,8 @@ ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
                              
   // The result structure takes care to note that we need to load the 
   // other declaration chains for this ID.
-  return RedeclarableResult(Reader, FirstDeclID);
+  return RedeclarableResult(Reader, FirstDeclID,
+                            static_cast<T *>(D)->getKind());
 }
 
 /// \brief Attempts to merge the given declaration (D) with another declaration