PreParsing inner funcs: Do fewer variable name lookups.

src/ast/scopes.cc

Index: src/ast/scopes.cc
diff --git a/src/ast/scopes.cc b/src/ast/scopes.cc
index 40c2648befadd946bba6b4b58ec6f6cd59b0fbfa..370569c1c82a3caf048fff0e5b45a0733f5f768f 100644
--- a/src/ast/scopes.cc
+++ b/src/ast/scopes.cc
@@ -53,7 +53,7 @@ Variable* VariableMap::Declare(Zone* zone, Scope* scope,
   return reinterpret_cast<Variable*>(p->value);
 }
 
-void VariableMap::DeclareName(Zone* zone, const AstRawString* name) {
+void VariableMap::LookupOrDeclareName(Zone* zone, const AstRawString* name) {

[jochen (gone - plz use gerrit), 2017/01/04 10:51:13]

LookupOrDeclare sounds strange, as the method doesn't really do an observable
lookup?

[marja, 2017/01/04 11:31:45]

Done.

   Entry* p =
       ZoneHashMap::LookupOrInsert(const_cast<AstRawString*>(name), name->hash(),
                                   ZoneAllocationPolicy(zone));
@@ -1037,11 +1037,10 @@ void Scope::DeclareVariableName(const AstRawString* name, VariableMode mode) {
   DCHECK(!is_eval_scope());
   DCHECK(is_declaration_scope() ||
          (IsLexicalVariableMode(mode) && is_block_scope()));
+  DCHECK(scope_info_.is_null());
 
   // Declare the variable in the declaration scope.
-  if (LookupLocal(name) == nullptr) {
-    variables_.DeclareName(zone(), name);
-  }
+  variables_.LookupOrDeclareName(zone(), name);
 }
 
 VariableProxy* Scope::NewUnresolved(AstNodeFactory* factory,