WIP: Parser: delay string internalization.

src/scopes.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "v8.h"
 
 #include "scopes.h"
 
 #include "accessors.h"
 #include "bootstrapper.h"
 #include "compiler.h"
 #include "messages.h"
 #include "scopeinfo.h"
 
 namespace v8 {
 namespace internal {
 
 // ----------------------------------------------------------------------------
 // Implementation of LocalsMap
 //
 // Note: We are storing the handle locations as key values in the hash map.
 //       When inserting a new variable via Declare(), we rely on the fact that
 //       the handle location remains alive for the duration of that variable
 //       use. Because a Variable holding a handle with the same location exists
 //       this is ensured.
 
-static bool Match(void* key1, void* key2) {
-  String* name1 = *reinterpret_cast<String**>(key1);
-  String* name2 = *reinterpret_cast<String**>(key2);
-  ASSERT(name1->IsInternalizedString());
-  ASSERT(name2->IsInternalizedString());
-  return name1 == name2;
-}
-
-
 VariableMap::VariableMap(Zone* zone)
-    : ZoneHashMap(Match, 8, ZoneAllocationPolicy(zone)),
+    : ZoneHashMap(ZoneHashMap::PointersMatch, 8, ZoneAllocationPolicy(zone)),
       zone_(zone) {}
 VariableMap::~VariableMap() {}
 
 
 Variable* VariableMap::Declare(
     Scope* scope,
-    Handle<String> name,
+    ParserSymbolTable::Symbol* name,
     VariableMode mode,
     bool is_valid_lhs,
     Variable::Kind kind,
     InitializationFlag initialization_flag,
     Interface* interface) {
-  Entry* p = ZoneHashMap::Lookup(name.location(), name->Hash(), true,
+  // ParserSymbolTable::Symbols are unambiguous, i.e., the same string is always
+  // represented by the same Symbol.
+  Entry* p = ZoneHashMap::Lookup(name, name->hash, true,
                                  ZoneAllocationPolicy(zone()));
   if (p->value == NULL) {
     // The variable has not been declared yet -> insert it.
-    ASSERT(p->key == name.location());
-    p->value = new(zone()) Variable(scope,
-                                    name,
-                                    mode,
-                                    is_valid_lhs,
-                                    kind,
-                                    initialization_flag,
-                                    interface);
+    ASSERT(p->key == name);
+    Variable* variable = new(zone()) Variable(scope,
+                                              name,
+                                              mode,
+                                              is_valid_lhs,
+                                              kind,
+                                              initialization_flag,
+                                              interface);
+    p->value = variable;
   }
   return reinterpret_cast<Variable*>(p->value);
 }
 
 
-Variable* VariableMap::Lookup(Handle<String> name) {
-  Entry* p = ZoneHashMap::Lookup(name.location(), name->Hash(), false,
+Variable* VariableMap::Lookup(ParserSymbolTable::Symbol* name) {
+  Entry* p = ZoneHashMap::Lookup(name, name->hash, false,
                                  ZoneAllocationPolicy(NULL));
   if (p != NULL) {
-    ASSERT(*reinterpret_cast<String**>(p->key) == *name);
+    ASSERT(reinterpret_cast<ParserSymbolTable::Symbol*>(p->key) == name);
     ASSERT(p->value != NULL);
     return reinterpret_cast<Variable*>(p->value);
   }
   return NULL;
 }
 
 
 // ----------------------------------------------------------------------------
 // Implementation of Scope
 
-Scope::Scope(Scope* outer_scope, ScopeType scope_type, Zone* zone)
+Scope::Scope(Scope* outer_scope, ScopeType scope_type,
+             ParserSymbolTable* symbol_table, Zone* zone)
     : isolate_(zone->isolate()),
       inner_scopes_(4, zone),
       variables_(zone),
       internals_(4, zone),
       temps_(4, zone),
       params_(4, zone),
       unresolved_(16, zone),
       decls_(4, zone),
-      interface_(FLAG_harmony_modules &&
-                 (scope_type == MODULE_SCOPE || scope_type == GLOBAL_SCOPE)
-                     ? Interface::NewModule(zone) : NULL),
+      interface_(FLAG_harmony_modules && (scope_type == MODULE_SCOPE ||
+                                          scope_type == GLOBAL_SCOPE)
+                     ? Interface::NewModule(zone)
+                     : NULL),

[rossberg, 2014/05/08 12:52:08]

Hey, you uglified it! :)

[marja, 2014/06/03 08:48:20]

Done.

       already_resolved_(false),
+      symbol_table_(symbol_table),
       zone_(zone) {
   SetDefaults(scope_type, outer_scope, Handle<ScopeInfo>::null());
   // The outermost scope must be a global scope.
   ASSERT(scope_type == GLOBAL_SCOPE || outer_scope != NULL);
   ASSERT(!HasIllegalRedeclaration());
 }
 
 
 Scope::Scope(Scope* inner_scope,
              ScopeType scope_type,
              Handle<ScopeInfo> scope_info,
+             ParserSymbolTable* symbol_table,
              Zone* zone)
     : isolate_(zone->isolate()),
       inner_scopes_(4, zone),
       variables_(zone),
       internals_(4, zone),
       temps_(4, zone),
       params_(4, zone),
       unresolved_(16, zone),
       decls_(4, zone),
       interface_(NULL),
       already_resolved_(true),
+      symbol_table_(symbol_table),
       zone_(zone) {
   SetDefaults(scope_type, NULL, scope_info);
   if (!scope_info.is_null()) {
     num_heap_slots_ = scope_info_->ContextLength();
   }
   // Ensure at least MIN_CONTEXT_SLOTS to indicate a materialized context.
   num_heap_slots_ = Max(num_heap_slots_,
                         static_cast<int>(Context::MIN_CONTEXT_SLOTS));
   AddInnerScope(inner_scope);
 }
 
 
-Scope::Scope(Scope* inner_scope, Handle<String> catch_variable_name, Zone* zone)
+Scope::Scope(Scope* inner_scope, ParserSymbolTable::Symbol* catch_variable_name,
+             ParserSymbolTable* symbol_table, Zone* zone)
     : isolate_(zone->isolate()),
       inner_scopes_(1, zone),
       variables_(zone),
       internals_(0, zone),
       temps_(0, zone),
       params_(0, zone),
       unresolved_(0, zone),
       decls_(0, zone),
       interface_(NULL),
       already_resolved_(true),
+      symbol_table_(symbol_table),
       zone_(zone) {
   SetDefaults(CATCH_SCOPE, NULL, Handle<ScopeInfo>::null());
   AddInnerScope(inner_scope);
   ++num_var_or_const_;
   num_heap_slots_ = Context::MIN_CONTEXT_SLOTS;
   Variable* variable = variables_.Declare(this,
                                           catch_variable_name,
                                           VAR,
                                           true,  // Valid left-hand side.
                                           Variable::NORMAL,
                                           kCreatedInitialized);
   AllocateHeapSlot(variable);
 }
 
 
 void Scope::SetDefaults(ScopeType scope_type,
                         Scope* outer_scope,
                         Handle<ScopeInfo> scope_info) {
   outer_scope_ = outer_scope;
   scope_type_ = scope_type;
-  scope_name_ = isolate_->factory()->empty_string();
+  scope_name_ = symbol_table_->empty_string();
   dynamics_ = NULL;
   receiver_ = NULL;
   function_ = NULL;
   arguments_ = NULL;
   illegal_redecl_ = NULL;
   scope_inside_with_ = false;
   scope_contains_with_ = false;
   scope_calls_eval_ = false;
   // Inherit the strict mode from the parent scope.
   strict_mode_ = outer_scope != NULL ? outer_scope->strict_mode_ : SLOPPY;
@@ skipping 21 matching lines @@
                                     Zone* zone) {
   // Reconstruct the outer scope chain from a closure's context chain.
   Scope* current_scope = NULL;
   Scope* innermost_scope = NULL;
   bool contains_with = false;
   while (!context->IsNativeContext()) {
     if (context->IsWithContext()) {
       Scope* with_scope = new(zone) Scope(current_scope,
                                           WITH_SCOPE,
                                           Handle<ScopeInfo>::null(),
+                                          global_scope->symbol_table_,
                                           zone);
       current_scope = with_scope;
       // All the inner scopes are inside a with.
       contains_with = true;
       for (Scope* s = innermost_scope; s != NULL; s = s->outer_scope()) {
         s->scope_inside_with_ = true;
       }
     } else if (context->IsGlobalContext()) {
       ScopeInfo* scope_info = ScopeInfo::cast(context->extension());
       current_scope = new(zone) Scope(current_scope,
                                       GLOBAL_SCOPE,
                                       Handle<ScopeInfo>(scope_info),
+                                      global_scope->symbol_table_,
                                       zone);
     } else if (context->IsModuleContext()) {
       ScopeInfo* scope_info = ScopeInfo::cast(context->module()->scope_info());
       current_scope = new(zone) Scope(current_scope,
                                       MODULE_SCOPE,
                                       Handle<ScopeInfo>(scope_info),
+                                      global_scope->symbol_table_,
                                       zone);
     } else if (context->IsFunctionContext()) {
       ScopeInfo* scope_info = context->closure()->shared()->scope_info();
       current_scope = new(zone) Scope(current_scope,
                                       FUNCTION_SCOPE,
                                       Handle<ScopeInfo>(scope_info),
+                                      global_scope->symbol_table_,
                                       zone);
     } else if (context->IsBlockContext()) {
       ScopeInfo* scope_info = ScopeInfo::cast(context->extension());
       current_scope = new(zone) Scope(current_scope,
                                       BLOCK_SCOPE,
                                       Handle<ScopeInfo>(scope_info),
+                                      global_scope->symbol_table_,
                                       zone);
     } else {
       ASSERT(context->IsCatchContext());
       String* name = String::cast(context->extension());
-      current_scope = new(zone) Scope(
-          current_scope, Handle<String>(name), zone);
+      current_scope = new(zone)
+          Scope(current_scope,
+                global_scope->symbol_table_->GetSymbol(Handle<String>(name)),
+                global_scope->symbol_table_, zone);
     }
     if (contains_with) current_scope->RecordWithStatement();
     if (innermost_scope == NULL) innermost_scope = current_scope;
 
     // Forget about a with when we move to a context for a different function.
     if (context->previous()->closure() != context->closure()) {
       contains_with = false;
     }
     context = context->previous();
   }
@@ skipping 53 matching lines @@
 
   // Declare convenience variables.
   // Declare and allocate receiver (even for the global scope, and even
   // if naccesses_ == 0).
   // NOTE: When loading parameters in the global scope, we must take
   // care not to access them as properties of the global object, but
   // instead load them directly from the stack. Currently, the only
   // such parameter is 'this' which is passed on the stack when
   // invoking scripts
   if (is_declaration_scope()) {
-    Variable* var =
-        variables_.Declare(this,
-                           isolate_->factory()->this_string(),
-                           VAR,
-                           false,
-                           Variable::THIS,
-                           kCreatedInitialized);
+    Variable* var = variables_.Declare(
+        this,
+        symbol_table_->this_string(),
+        VAR,
+        false,
+        Variable::THIS,
+        kCreatedInitialized);
     var->AllocateTo(Variable::PARAMETER, -1);
     receiver_ = var;
   } else {
     ASSERT(outer_scope() != NULL);
     receiver_ = outer_scope()->receiver();
   }
 
   if (is_function_scope()) {
     // Declare 'arguments' variable which exists in all functions.
     // Note that it might never be accessed, in which case it won't be
     // allocated during variable allocation.
-    variables_.Declare(this,
-                       isolate_->factory()->arguments_string(),
-                       VAR,
-                       true,
-                       Variable::ARGUMENTS,
-                       kCreatedInitialized);
+    variables_.Declare(
+        this,
+        symbol_table_->arguments_string(),
+        VAR,
+        true,
+        Variable::ARGUMENTS,
+        kCreatedInitialized);
   }
 }
 
 
 Scope* Scope::FinalizeBlockScope() {
   ASSERT(is_block_scope());
   ASSERT(internals_.is_empty());
   ASSERT(temps_.is_empty());
   ASSERT(params_.is_empty());
 
@@ skipping 14 matching lines @@
 
   // Move unresolved variables
   for (int i = 0; i < unresolved_.length(); i++) {
     outer_scope()->unresolved_.Add(unresolved_[i], zone());
   }
 
   return NULL;
 }
 
 
-Variable* Scope::LocalLookup(Handle<String> name) {
+Variable* Scope::LocalLookup(ParserSymbolTable::Symbol* name) {
   Variable* result = variables_.Lookup(name);
   if (result != NULL || scope_info_.is_null()) {
     return result;
   }
+  Handle<String> name_handle = name->string();
   // If we have a serialized scope info, we might find the variable there.
   // There should be no local slot with the given name.
-  ASSERT(scope_info_->StackSlotIndex(*name) < 0);
+  ASSERT(scope_info_->StackSlotIndex(*name_handle) < 0);
 
   // Check context slot lookup.
   VariableMode mode;
   Variable::Location location = Variable::CONTEXT;
   InitializationFlag init_flag;
-  int index = ScopeInfo::ContextSlotIndex(scope_info_, name, &mode, &init_flag);
+  int index =
+      ScopeInfo::ContextSlotIndex(scope_info_, name_handle, &mode, &init_flag);
   if (index < 0) {
     // Check parameters.
-    index = scope_info_->ParameterIndex(*name);
+    index = scope_info_->ParameterIndex(*name_handle);
     if (index < 0) return NULL;
 
     mode = DYNAMIC;
     location = Variable::LOOKUP;
     init_flag = kCreatedInitialized;
   }
 
-  Variable* var = variables_.Declare(this, name, mode, true, Variable::NORMAL,
-                                     init_flag);
+  Variable* var =
+      variables_.Declare(this, name, mode, true, Variable::NORMAL, init_flag);
   var->AllocateTo(location, index);
   return var;
 }
 
 
-Variable* Scope::LookupFunctionVar(Handle<String> name,
+Variable* Scope::LookupFunctionVar(ParserSymbolTable::Symbol* name,
                                    AstNodeFactory<AstNullVisitor>* factory) {
-  if (function_ != NULL && function_->proxy()->name().is_identical_to(name)) {
+  if (function_ != NULL && function_->proxy()->raw_name() == name) {
     return function_->proxy()->var();
   } else if (!scope_info_.is_null()) {
     // If we are backed by a scope info, try to lookup the variable there.
     VariableMode mode;
-    int index = scope_info_->FunctionContextSlotIndex(*name, &mode);
+    int index = scope_info_->FunctionContextSlotIndex(*(name->string()), &mode);
     if (index < 0) return NULL;
     Variable* var = new(zone()) Variable(
         this, name, mode, true /* is valid LHS */,
         Variable::NORMAL, kCreatedInitialized);
     VariableProxy* proxy = factory->NewVariableProxy(var);
     VariableDeclaration* declaration = factory->NewVariableDeclaration(
         proxy, mode, this, RelocInfo::kNoPosition);
     DeclareFunctionVar(declaration);
     var->AllocateTo(Variable::CONTEXT, index);
     return var;
   } else {
     return NULL;
   }
 }
 
 
-Variable* Scope::Lookup(Handle<String> name) {
+Variable* Scope::Lookup(ParserSymbolTable::Symbol* name) {
   for (Scope* scope = this;
        scope != NULL;
        scope = scope->outer_scope()) {
     Variable* var = scope->LocalLookup(name);
     if (var != NULL) return var;
   }
   return NULL;
 }
 
 
-void Scope::DeclareParameter(Handle<String> name, VariableMode mode) {
+void Scope::DeclareParameter(ParserSymbolTable::Symbol* name,
+                             VariableMode mode) {
   ASSERT(!already_resolved());
   ASSERT(is_function_scope());
-  Variable* var = variables_.Declare(this, name, mode, true, Variable::NORMAL,
-                                     kCreatedInitialized);
+  Variable* var = variables_.Declare(this, name, mode, true,
+                                     Variable::NORMAL, kCreatedInitialized);
   params_.Add(var, zone());
 }
 
 
-Variable* Scope::DeclareLocal(Handle<String> name,
+Variable* Scope::DeclareLocal(ParserSymbolTable::Symbol* name,
                               VariableMode mode,
                               InitializationFlag init_flag,
                               Interface* interface) {
   ASSERT(!already_resolved());
   // This function handles VAR, LET, and CONST modes.  DYNAMIC variables are
   // introduces during variable allocation, INTERNAL variables are allocated
   // explicitly, and TEMPORARY variables are allocated via NewTemporary().
   ASSERT(IsDeclaredVariableMode(mode));
   ++num_var_or_const_;
   return variables_.Declare(
       this, name, mode, true, Variable::NORMAL, init_flag, interface);
 }
 
 
-Variable* Scope::DeclareDynamicGlobal(Handle<String> name) {
+Variable* Scope::DeclareDynamicGlobal(ParserSymbolTable::Symbol* name) {
   ASSERT(is_global_scope());
   return variables_.Declare(this,
                             name,
                             DYNAMIC_GLOBAL,
                             true,
                             Variable::NORMAL,
                             kCreatedInitialized);
 }
 
 
 void Scope::RemoveUnresolved(VariableProxy* var) {
   // Most likely (always?) any variable we want to remove
   // was just added before, so we search backwards.
   for (int i = unresolved_.length(); i-- > 0;) {
     if (unresolved_[i] == var) {
       unresolved_.Remove(i);
       return;
     }
   }
 }
 
 
-Variable* Scope::NewInternal(Handle<String> name) {
+Variable* Scope::NewInternal(ParserSymbolTable::Symbol* name) {
   ASSERT(!already_resolved());
   Variable* var = new(zone()) Variable(this,
                                        name,
                                        INTERNAL,
                                        false,
                                        Variable::NORMAL,
                                        kCreatedInitialized);
   internals_.Add(var, zone());
   return var;
 }
 
 
-Variable* Scope::NewTemporary(Handle<String> name) {
+Variable* Scope::NewTemporary(ParserSymbolTable::Symbol* name) {
   ASSERT(!already_resolved());
   Variable* var = new(zone()) Variable(this,
                                        name,
                                        TEMPORARY,
                                        true,
                                        Variable::NORMAL,
                                        kCreatedInitialized);
   temps_.Add(var, zone());
   return var;
 }
@@ skipping 17 matching lines @@
   ASSERT(HasIllegalRedeclaration());
   illegal_redecl_->Accept(visitor);
 }
 
 
 Declaration* Scope::CheckConflictingVarDeclarations() {
   int length = decls_.length();
   for (int i = 0; i < length; i++) {
     Declaration* decl = decls_[i];
     if (decl->mode() != VAR) continue;
-    Handle<String> name = decl->proxy()->name();
+    ParserSymbolTable::Symbol* name = decl->proxy()->raw_name();
 
     // Iterate through all scopes until and including the declaration scope.
     Scope* previous = NULL;
     Scope* current = decl->scope();
     do {
       // There is a conflict if there exists a non-VAR binding.
       Variable* other_var = current->variables_.Lookup(name);
       if (other_var != NULL && other_var->mode() != VAR) {
         return decl;
       }
@@ skipping 222 matching lines @@
   UNREACHABLE();
   return NULL;
 }
 
 
 static void Indent(int n, const char* str) {
   PrintF("%*s%s", n, "", str);
 }
 
 
-static void PrintName(Handle<String> name) {
-  SmartArrayPointer<char> s = name->ToCString(DISALLOW_NULLS);
-  PrintF("%s", s.get());
+static void PrintName(ParserSymbolTable::Symbol* name) {
+  PrintF("%.*s", name->literal_bytes.length(), name->literal_bytes.start());
 }
 
 
 static void PrintLocation(Variable* var) {
   switch (var->location()) {
     case Variable::UNALLOCATED:
       break;
     case Variable::PARAMETER:
       PrintF("parameter[%d]", var->index());
       break;
     case Variable::LOCAL:
       PrintF("local[%d]", var->index());
       break;
     case Variable::CONTEXT:
       PrintF("context[%d]", var->index());
       break;
     case Variable::LOOKUP:
       PrintF("lookup");
       break;
   }
 }
 
 
 static void PrintVar(int indent, Variable* var) {
   if (var->is_used() || !var->IsUnallocated()) {
     Indent(indent, Variable::Mode2String(var->mode()));
     PrintF(" ");
-    PrintName(var->name());
+    PrintName(var->raw_name());
     PrintF(";  // ");
     PrintLocation(var);
     if (var->has_forced_context_allocation()) {
       if (!var->IsUnallocated()) PrintF(", ");
       PrintF("forced context allocation");
     }
     PrintF("\n");
   }
 }
 
 
 static void PrintMap(int indent, VariableMap* map) {
   for (VariableMap::Entry* p = map->Start(); p != NULL; p = map->Next(p)) {
     Variable* var = reinterpret_cast<Variable*>(p->value);
     PrintVar(indent, var);
   }
 }
 
 
 void Scope::Print(int n) {
   int n0 = (n > 0 ? n : 0);
   int n1 = n0 + 2;  // indentation
 
   // Print header.
   Indent(n0, Header(scope_type_));
-  if (scope_name_->length() > 0) {
+  if (scope_name_ != NULL) {
     PrintF(" ");
     PrintName(scope_name_);
   }
 
   // Print parameters, if any.
   if (is_function_scope()) {
     PrintF(" (");
     for (int i = 0; i < params_.length(); i++) {
       if (i > 0) PrintF(", ");
-      PrintName(params_[i]->name());
+      PrintName(params_[i]->raw_name());
     }
     PrintF(")");
   }
 
   PrintF(" { // (%d, %d)\n", start_position(), end_position());
 
   // Function name, if any (named function literals, only).
   if (function_ != NULL) {
     Indent(n1, "// (local) function name: ");
-    PrintName(function_->proxy()->name());
+    PrintName(function_->proxy()->raw_name());
     PrintF("\n");
   }
 
   // Scope info.
   if (HasTrivialOuterContext()) {
     Indent(n1, "// scope has trivial outer context\n");
   }
   if (strict_mode() == STRICT) {
     Indent(n1, "// strict mode scope\n");
   }
@@ skipping 47 matching lines @@
       PrintF("\n");
       inner_scopes_[i]->Print(n1);
     }
   }
 
   Indent(n0, "}\n");
 }
 #endif  // DEBUG
 
 
-Variable* Scope::NonLocal(Handle<String> name, VariableMode mode) {
+Variable* Scope::NonLocal(ParserSymbolTable::Symbol* name, VariableMode mode) {
   if (dynamics_ == NULL) dynamics_ = new(zone()) DynamicScopePart(zone());
   VariableMap* map = dynamics_->GetMap(mode);
   Variable* var = map->Lookup(name);
   if (var == NULL) {
     // Declare a new non-local.
     InitializationFlag init_flag = (mode == VAR)
         ? kCreatedInitialized : kNeedsInitialization;
     var = map->Declare(NULL,
                        name,
                        mode,
                        true,
                        Variable::NORMAL,
                        init_flag);
     // Allocate it by giving it a dynamic lookup.
     var->AllocateTo(Variable::LOOKUP, -1);
   }
   return var;
 }
 
 
-Variable* Scope::LookupRecursive(Handle<String> name,
+Variable* Scope::LookupRecursive(ParserSymbolTable::Symbol* name,
                                  BindingKind* binding_kind,
                                  AstNodeFactory<AstNullVisitor>* factory) {
   ASSERT(binding_kind != NULL);
   if (already_resolved() && is_with_scope()) {
     // Short-cut: if the scope is deserialized from a scope info, variable
     // allocation is already fixed.  We can simply return with dynamic lookup.
     *binding_kind = DYNAMIC_LOOKUP;
     return NULL;
   }
 
@@ skipping 45 matching lines @@
       *binding_kind = UNBOUND_EVAL_SHADOWED;
     }
   }
   return var;
 }
 
 
 bool Scope::ResolveVariable(CompilationInfo* info,
                             VariableProxy* proxy,
                             AstNodeFactory<AstNullVisitor>* factory) {
+  ASSERT(!proxy->name().is_null());  // proxy should be internalized by now.
   ASSERT(info->global_scope()->is_global_scope());
 
   // If the proxy is already resolved there's nothing to do
   // (functions and consts may be resolved by the parser).
   if (proxy->var() != NULL) return true;
 
   // Otherwise, try to resolve the variable.
   BindingKind binding_kind;
-  Variable* var = LookupRecursive(proxy->name(), &binding_kind, factory);
+  Variable* var = LookupRecursive(proxy->raw_name(), &binding_kind, factory);
   switch (binding_kind) {
     case BOUND:
       // We found a variable binding.
       break;
 
     case BOUND_EVAL_SHADOWED:
       // We either found a variable binding that might be shadowed by eval  or
       // gave up on it (e.g. by encountering a local with the same in the outer
       // scope which was not promoted to a context, this can happen if we use
       // debugger to evaluate arbitrary expressions at a break point).
       if (var->IsGlobalObjectProperty()) {
-        var = NonLocal(proxy->name(), DYNAMIC_GLOBAL);
+        var = NonLocal(proxy->raw_name(), DYNAMIC_GLOBAL);
       } else if (var->is_dynamic()) {
-        var = NonLocal(proxy->name(), DYNAMIC);
+        var = NonLocal(proxy->raw_name(), DYNAMIC);
       } else {
         Variable* invalidated = var;
-        var = NonLocal(proxy->name(), DYNAMIC_LOCAL);
+        var = NonLocal(proxy->raw_name(), DYNAMIC_LOCAL);
         var->set_local_if_not_shadowed(invalidated);
       }
       break;
 
     case UNBOUND:
       // No binding has been found. Declare a variable on the global object.
-      var = info->global_scope()->DeclareDynamicGlobal(proxy->name());
+      var = info->global_scope()->DeclareDynamicGlobal(proxy->raw_name());
       break;
 
     case UNBOUND_EVAL_SHADOWED:
       // No binding has been found. But some scope makes a sloppy 'eval' call.
-      var = NonLocal(proxy->name(), DYNAMIC_GLOBAL);
+      var = NonLocal(proxy->raw_name(), DYNAMIC_GLOBAL);
       break;
 
     case DYNAMIC_LOOKUP:
       // The variable could not be resolved statically.
-      var = NonLocal(proxy->name(), DYNAMIC);
+      var = NonLocal(proxy->raw_name(), DYNAMIC);
       break;
   }
 
   ASSERT(var != NULL);
 
   if (FLAG_harmony_scoping && strict_mode() == STRICT &&
       var->is_const_mode() && proxy->IsLValue()) {
     // Assignment to const. Throw a syntax error.
     MessageLocation location(
         info->script(), proxy->position(), proxy->position());
     Isolate* isolate = info->isolate();
     Factory* factory = isolate->factory();
     Handle<JSArray> array = factory->NewJSArray(0);
     Handle<Object> result =
         factory->NewSyntaxError("harmony_const_assign", array);
     isolate->Throw(*result, &location);
     return false;
   }
 
   if (FLAG_harmony_modules) {
     bool ok;
 #ifdef DEBUG
     if (FLAG_print_interface_details)
+      // FIXME
       PrintF("# Resolve %s:\n", var->name()->ToAsciiArray());
 #endif
     proxy->interface()->Unify(var->interface(), zone(), &ok);
     if (!ok) {
 #ifdef DEBUG
       if (FLAG_print_interfaces) {
         PrintF("SCOPES TYPE ERROR\n");
         PrintF("proxy: ");
         proxy->interface()->Print();
         PrintF("var: ");
@@ skipping 60 matching lines @@
   }
 
   return scope_calls_eval_ || inner_scope_calls_eval_;
 }
 
 
 bool Scope::MustAllocate(Variable* var) {
   // Give var a read/write use if there is a chance it might be accessed
   // via an eval() call.  This is only possible if the variable has a
   // visible name.
-  if ((var->is_this() || var->name()->length() > 0) &&
+  if ((var->is_this() || var->raw_name()->literal_bytes.length() > 0) &&
       (var->has_forced_context_allocation() ||
        scope_calls_eval_ ||
        inner_scope_calls_eval_ ||
        scope_contains_with_ ||
        is_catch_scope() ||
        is_block_scope() ||
        is_module_scope() ||
        is_global_scope())) {
     var->set_is_used(true);
   }
@@ skipping 40 matching lines @@
 }
 
 
 void Scope::AllocateHeapSlot(Variable* var) {
   var->AllocateTo(Variable::CONTEXT, num_heap_slots_++);
 }
 
 
 void Scope::AllocateParameterLocals() {
   ASSERT(is_function_scope());
-  Variable* arguments = LocalLookup(isolate_->factory()->arguments_string());
+  Variable* arguments = LocalLookup(symbol_table_->arguments_string());
   ASSERT(arguments != NULL);  // functions have 'arguments' declared implicitly
 
   bool uses_sloppy_arguments = false;
 
   if (MustAllocate(arguments) && !HasArgumentsParameter()) {
     // 'arguments' is used. Unless there is also a parameter called
     // 'arguments', we must be conservative and allocate all parameters to
     // the context assuming they will be captured by the arguments object.
     // If we have a parameter named 'arguments', a (new) value is always
     // assigned to it via the function invocation. Then 'arguments' denotes
@@ skipping 120 matching lines @@
 
   // Allocation done.
   ASSERT(num_heap_slots_ == 0 || num_heap_slots_ >= Context::MIN_CONTEXT_SLOTS);
 }
 
 
 void Scope::AllocateModulesRecursively(Scope* host_scope) {
   if (already_resolved()) return;
   if (is_module_scope()) {
     ASSERT(interface_->IsFrozen());
-    Handle<String> name = isolate_->factory()->InternalizeOneByteString(
-        STATIC_ASCII_VECTOR(".module"));
     ASSERT(module_var_ == NULL);
-    module_var_ = host_scope->NewInternal(name);
+    module_var_ =
+        host_scope->NewInternal(symbol_table_->dot_module_string());
     ++host_scope->num_modules_;
   }
 
   for (int i = 0; i < inner_scopes_.length(); i++) {
     Scope* inner_scope = inner_scopes_.at(i);
     inner_scope->AllocateModulesRecursively(host_scope);
   }
 }
 
 
 int Scope::StackLocalCount() const {
   return num_stack_slots() -
       (function_ != NULL && function_->proxy()->var()->IsStackLocal() ? 1 : 0);
 }
 
 
 int Scope::ContextLocalCount() const {
   if (num_heap_slots() == 0) return 0;
   return num_heap_slots() - Context::MIN_CONTEXT_SLOTS -
       (function_ != NULL && function_->proxy()->var()->IsContextSlot() ? 1 : 0);
 }
 
 } }  // namespace v8::internal