Factor static-local nil IntrusivePtrs to global locations

Minor optimization to remove any run-time impact.

src/EventHandler.cc

@@ -28,8 +28,6 @@ EventHandler::operator bool() const
 
 const IntrusivePtr<FuncType>& EventHandler::GetType(bool check_export)
 	{
-	static IntrusivePtr<FuncType> nil;
-
 	if ( type )
 		return type;
 
@@ -37,10 +35,10 @@ const IntrusivePtr<FuncType>& EventHandler::GetType(bool check_export)
 	                           check_export);
 
 	if ( ! id )
-		return nil;
+		return FuncType::nil;
 
 	if ( id->GetType()->Tag() != TYPE_FUNC )
-		return nil;
+		return FuncType::nil;
 
 	type = id->GetType<FuncType>();
 	return type;

src/Func.h

@@ -30,6 +30,8 @@ class Scope;
 
 class Func : public BroObj {
 public:
+	static inline const IntrusivePtr<Func> nil;
+
 	enum Kind { BRO_FUNC, BUILTIN_FUNC };
 
 	explicit Func(Kind arg_kind);
@@ -99,10 +101,7 @@ public:
 
 	uint32_t GetUniqueFuncID() const { return unique_id; }
 	static const IntrusivePtr<Func>& GetFuncPtrByID(uint32_t id)
-		{
-		static IntrusivePtr<Func> nil;
-		return id >= unique_ids.size() ? nil : unique_ids[id];
-		}
+		{ return id >= unique_ids.size() ? Func::nil : unique_ids[id]; }
 
 protected:
 	Func();

src/ID.h

@@ -28,6 +28,8 @@ typedef enum { SCOPE_FUNCTION, SCOPE_MODULE, SCOPE_GLOBAL } IDScope;
 
 class ID final : public BroObj, public notifier::Modifiable {
 public:
+	static inline const IntrusivePtr<ID> nil;
+
 	ID(const char* name, IDScope arg_scope, bool arg_is_export);
 	~ID() override;
 

src/Scope.cc

@@ -14,7 +14,6 @@ typedef PList<Scope> scope_list;
 
 static scope_list scopes;
 static Scope* top_scope;
-static IntrusivePtr<ID> nil_id;
 
 Scope::Scope(IntrusivePtr<ID> id, attr_list* al)
 	: scope_id(std::move(id))
@@ -64,7 +63,7 @@ const IntrusivePtr<ID>& Scope::Find(std::string_view name) const
 	if ( entry != local.end() )
 		return entry->second;
 
-	return nil_id;
+	return ID::nil;
 	}
 
 IntrusivePtr<ID> Scope::Remove(std::string_view name)
@@ -172,7 +171,7 @@ const IntrusivePtr<ID>& lookup_ID(const char* name, const char* curr_module,
 		return global_scope()->Find(globalname);
 		}
 
-	return nil_id;
+	return ID::nil;
 	}
 
 IntrusivePtr<ID> install_ID(const char* name, const char* module_name,

src/Type.cc

@@ -111,8 +111,7 @@ int BroType::MatchesIndex(ListExpr* const index) const
 
 const IntrusivePtr<BroType>& BroType::Yield() const
 	{
-	static IntrusivePtr<BroType> nil;
-	return nil;
+	return BroType::nil;
 	}
 
 bool BroType::HasField(const char* /* field */) const

src/Type.h

@@ -141,6 +141,8 @@ const int MATCHES_INDEX_VECTOR = 2;
 
 class BroType : public BroObj {
 public:
+	static inline const IntrusivePtr<BroType> nil;
+
 	explicit BroType(TypeTag tag, bool base_type = false);
 
 	// Performs a shallow clone operation of the Bro type.
@@ -456,6 +458,8 @@ protected:
 
 class FuncType final : public BroType {
 public:
+	static inline const IntrusivePtr<FuncType> nil;
+
 	/**
 	 * Prototype is only currently used for events and hooks which declare
 	 * multiple signature prototypes that allow users to have handlers

src/Val.cc

@@ -1897,9 +1897,6 @@ IntrusivePtr<Val> TableVal::Default(const IntrusivePtr<Val>& index)
 
 const IntrusivePtr<Val>& TableVal::Find(const IntrusivePtr<Val>& index)
 	{
-	static IntrusivePtr<Val> nil;
-	static IntrusivePtr<Val> exists = val_mgr->True();
-
 	if ( subnets )
 		{
 		TableEntryVal* v = (TableEntryVal*) subnets->Lookup(index.get());
@@ -1911,10 +1908,10 @@ const IntrusivePtr<Val>& TableVal::Find(const IntrusivePtr<Val>& index)
 			if ( v->GetVal() )
 				return v->GetVal();
 
-			return exists;
+			return val_mgr->True();
 			}
 
-		return nil;
+		return Val::nil;
 		}
 
 	const PDict<TableEntryVal>* tbl = AsTable();
@@ -1935,12 +1932,12 @@ const IntrusivePtr<Val>& TableVal::Find(const IntrusivePtr<Val>& index)
 				if ( v->GetVal() )
 					return v->GetVal();
 
-				return exists;
+				return val_mgr->True();
 				}
 			}
 		}
 
-	return nil;
+	return Val::nil;
 	}
 
 IntrusivePtr<Val> TableVal::FindOrDefault(const IntrusivePtr<Val>& index)
@@ -3139,10 +3136,8 @@ bool VectorVal::AddTo(Val* val, bool /* is_first_init */) const
 
 const IntrusivePtr<Val>& VectorVal::At(unsigned int index) const
 	{
-	static IntrusivePtr<Val> nil;
-
 	if ( index >= val.vector_val->size() )
-		return nil;
+		return Val::nil;
 
 	return (*val.vector_val)[index];
 	}

src/Val.h

@@ -118,6 +118,8 @@ union BroValUnion {
 
 class Val : public BroObj {
 public:
+	static inline const IntrusivePtr<Val> nil;
+
 	Val(double d, TypeTag t)
 		: val(d), type(base_type(t))
 		{}