remove the type_info identifier cache. Compared to the cost

of doing the lookup_decl, the hash lookup is cheap.  Also,
typeid doesn't happen enough in real world code to worry about
it.

I'd like to eventually get rid of KnownFunctionIDs from Sema
also, but today is not that day.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@59711 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/Sema.cpp

@@ -103,9 +103,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer)
   KnownFunctionIDs[id_vsnprintf_chk] = &IT.get("__builtin___vsnprintf_chk");
   KnownFunctionIDs[id_vprintf]       = &IT.get("vprintf");
 
-  Ident_TypeInfo = 0;
   StdNamespace = 0;
-
   TUScope = 0;
   if (getLangOptions().CPlusPlus)
     FieldCollector.reset(new CXXFieldCollector());

lib/Sema/Sema.h

@@ -192,9 +192,6 @@ public:
   /// This list is populated upon the creation of a Sema object.    
   IdentifierInfo* KnownFunctionIDs[id_num_known_functions];
 
-  /// Identifiers used by the C++ language
-  IdentifierInfo *Ident_TypeInfo; // "type_info" - lazily created
-
   /// Translation Unit Scope - useful to Objective-C actions that need
   /// to lookup file scope declarations in the "ordinary" C decl namespace.
   /// For example, user-defined classes, built-in "id" type, etc.

lib/Sema/SemaExprCXX.cpp

@@ -55,21 +55,16 @@ Action::ExprResult
 Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
                      bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
   const NamespaceDecl *StdNs = GetStdNamespace();
-  if (!StdNs) {
-    Diag(OpLoc, diag::err_need_header_before_typeid);
-    return ExprResult(true);
-  }
-  if (!Ident_TypeInfo) {
-    Ident_TypeInfo = &PP.getIdentifierTable().get("type_info");
-  }
-  Decl *TypeInfoDecl = LookupDecl(Ident_TypeInfo,
+  if (!StdNs)
+    return Diag(OpLoc, diag::err_need_header_before_typeid);
+  
+  IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
+  Decl *TypeInfoDecl = LookupDecl(TypeInfoII,
                                   Decl::IDNS_Tag | Decl::IDNS_Ordinary,
                                   0, StdNs, /*createBuiltins=*/false);
   RecordDecl *TypeInfoRecordDecl = dyn_cast_or_null<RecordDecl>(TypeInfoDecl);
-  if (!TypeInfoRecordDecl) {
-    Diag(OpLoc, diag::err_need_header_before_typeid);
-    return ExprResult(true);
-  }
+  if (!TypeInfoRecordDecl)
+    return Diag(OpLoc, diag::err_need_header_before_typeid);
 
   QualType TypeInfoType = Context.getTypeDeclType(TypeInfoRecordDecl);