Revert of Put Scopes into temporary Zone

src/ast/ast.h

Index: src/ast/ast.h
diff --git a/src/ast/ast.h b/src/ast/ast.h
index 85f15fb2d0a00a32a1959f49acf482711fcaebf8..19e530c915912f5df9a28ca6581df7b6d8cc40d0 100644
--- a/src/ast/ast.h
+++ b/src/ast/ast.h
@@ -1690,7 +1690,6 @@
   VariableProxy(Zone* zone, const AstRawString* name,
                 Variable::Kind variable_kind, int start_position,
                 int end_position);
-  VariableProxy(Zone* zone, const VariableProxy* copy_from);
   static int parent_num_ids() { return Expression::num_ids(); }
   int local_id(int n) const { return base_id() + parent_num_ids() + n; }
 
@@ -3044,22 +3043,27 @@
 class AstNodeFactory final BASE_EMBEDDED {
  public:
   explicit AstNodeFactory(AstValueFactory* ast_value_factory)
-      : zone_(nullptr), ast_value_factory_(ast_value_factory) {
+      : local_zone_(nullptr),
+        parser_zone_(nullptr),
+        ast_value_factory_(ast_value_factory) {
     if (ast_value_factory != nullptr) {
-      zone_ = ast_value_factory->zone();
+      local_zone_ = ast_value_factory->zone();
+      parser_zone_ = ast_value_factory->zone();
     }
   }
 
   AstValueFactory* ast_value_factory() const { return ast_value_factory_; }
   void set_ast_value_factory(AstValueFactory* ast_value_factory) {
     ast_value_factory_ = ast_value_factory;
-    zone_ = ast_value_factory->zone();
+    local_zone_ = ast_value_factory->zone();
+    parser_zone_ = ast_value_factory->zone();
   }
 
   VariableDeclaration* NewVariableDeclaration(VariableProxy* proxy,
                                               VariableMode mode, Scope* scope,
                                               int pos) {
-    return new (zone_) VariableDeclaration(zone_, proxy, mode, scope, pos);
+    return new (parser_zone_)
+        VariableDeclaration(parser_zone_, proxy, mode, scope, pos);
   }
 
   FunctionDeclaration* NewFunctionDeclaration(VariableProxy* proxy,
@@ -3067,18 +3071,19 @@
                                               FunctionLiteral* fun,
                                               Scope* scope,
                                               int pos) {
-    return new (zone_) FunctionDeclaration(zone_, proxy, mode, fun, scope, pos);
+    return new (parser_zone_)
+        FunctionDeclaration(parser_zone_, proxy, mode, fun, scope, pos);
   }
 
   Block* NewBlock(ZoneList<const AstRawString*>* labels, int capacity,
                   bool ignore_completion_value, int pos) {
-    return new (zone_)
-        Block(zone_, labels, capacity, ignore_completion_value, pos);
+    return new (local_zone_)
+        Block(local_zone_, labels, capacity, ignore_completion_value, pos);
   }
 
 #define STATEMENT_WITH_LABELS(NodeType)                                     \
   NodeType* New##NodeType(ZoneList<const AstRawString*>* labels, int pos) { \
-    return new (zone_) NodeType(zone_, labels, pos);                        \
+    return new (local_zone_) NodeType(local_zone_, labels, pos);            \
   }
   STATEMENT_WITH_LABELS(DoWhileStatement)
   STATEMENT_WITH_LABELS(WhileStatement)
@@ -3091,10 +3096,10 @@
                                         int pos) {
     switch (visit_mode) {
       case ForEachStatement::ENUMERATE: {
-        return new (zone_) ForInStatement(zone_, labels, pos);
+        return new (local_zone_) ForInStatement(local_zone_, labels, pos);
       }
       case ForEachStatement::ITERATE: {
-        return new (zone_) ForOfStatement(zone_, labels, pos);
+        return new (local_zone_) ForOfStatement(local_zone_, labels, pos);
       }
     }
     UNREACHABLE();
@@ -3102,41 +3107,42 @@
   }
 
   ExpressionStatement* NewExpressionStatement(Expression* expression, int pos) {
-    return new (zone_) ExpressionStatement(zone_, expression, pos);
+    return new (local_zone_) ExpressionStatement(local_zone_, expression, pos);
   }
 
   ContinueStatement* NewContinueStatement(IterationStatement* target, int pos) {
-    return new (zone_) ContinueStatement(zone_, target, pos);
+    return new (local_zone_) ContinueStatement(local_zone_, target, pos);
   }
 
   BreakStatement* NewBreakStatement(BreakableStatement* target, int pos) {
-    return new (zone_) BreakStatement(zone_, target, pos);
+    return new (local_zone_) BreakStatement(local_zone_, target, pos);
   }
 
   ReturnStatement* NewReturnStatement(Expression* expression, int pos) {
-    return new (zone_) ReturnStatement(zone_, expression, pos);
+    return new (local_zone_) ReturnStatement(local_zone_, expression, pos);
   }
 
   WithStatement* NewWithStatement(Scope* scope,
                                   Expression* expression,
                                   Statement* statement,
                                   int pos) {
-    return new (zone_) WithStatement(zone_, scope, expression, statement, pos);
+    return new (local_zone_)
+        WithStatement(local_zone_, scope, expression, statement, pos);
   }
 
   IfStatement* NewIfStatement(Expression* condition,
                               Statement* then_statement,
                               Statement* else_statement,
                               int pos) {
-    return new (zone_)
-        IfStatement(zone_, condition, then_statement, else_statement, pos);
+    return new (local_zone_) IfStatement(local_zone_, condition, then_statement,
+                                         else_statement, pos);
   }
 
   TryCatchStatement* NewTryCatchStatement(Block* try_block, Scope* scope,
                                           Variable* variable,
                                           Block* catch_block, int pos) {
-    return new (zone_)
-        TryCatchStatement(zone_, try_block, scope, variable, catch_block,
+    return new (local_zone_)
+        TryCatchStatement(local_zone_, try_block, scope, variable, catch_block,
                           HandlerTable::CAUGHT, pos);
   }
 
@@ -3145,8 +3151,8 @@
                                                     Variable* variable,
                                                     Block* catch_block,
                                                     int pos) {
-    return new (zone_)
-        TryCatchStatement(zone_, try_block, scope, variable, catch_block,
+    return new (local_zone_)
+        TryCatchStatement(local_zone_, try_block, scope, variable, catch_block,
                           HandlerTable::UNCAUGHT, pos);
   }
 
@@ -3155,81 +3161,88 @@
                                                           Variable* variable,
                                                           Block* catch_block,
                                                           int pos) {
-    return new (zone_)
-        TryCatchStatement(zone_, try_block, scope, variable, catch_block,
+    return new (local_zone_)
+        TryCatchStatement(local_zone_, try_block, scope, variable, catch_block,
                           HandlerTable::PROMISE, pos);
   }
 
   TryFinallyStatement* NewTryFinallyStatement(Block* try_block,
                                               Block* finally_block, int pos) {
-    return new (zone_)
-        TryFinallyStatement(zone_, try_block, finally_block, pos);
+    return new (local_zone_)
+        TryFinallyStatement(local_zone_, try_block, finally_block, pos);
   }
 
   DebuggerStatement* NewDebuggerStatement(int pos) {
-    return new (zone_) DebuggerStatement(zone_, pos);
+    return new (local_zone_) DebuggerStatement(local_zone_, pos);
   }
 
   EmptyStatement* NewEmptyStatement(int pos) {
-    return new (zone_) EmptyStatement(zone_, pos);
+    return new (local_zone_) EmptyStatement(local_zone_, pos);
   }
 
   SloppyBlockFunctionStatement* NewSloppyBlockFunctionStatement(
       Statement* statement, Scope* scope) {
-    return new (zone_) SloppyBlockFunctionStatement(zone_, statement, scope);
+    return new (parser_zone_)
+        SloppyBlockFunctionStatement(parser_zone_, statement, scope);
   }
 
   CaseClause* NewCaseClause(
       Expression* label, ZoneList<Statement*>* statements, int pos) {
-    return new (zone_) CaseClause(zone_, label, statements, pos);
+    return new (local_zone_) CaseClause(local_zone_, label, statements, pos);
   }
 
   Literal* NewStringLiteral(const AstRawString* string, int pos) {
-    return new (zone_)
-        Literal(zone_, ast_value_factory_->NewString(string), pos);
+    return new (local_zone_)
+        Literal(local_zone_, ast_value_factory_->NewString(string), pos);
   }
 
   // A JavaScript symbol (ECMA-262 edition 6).
   Literal* NewSymbolLiteral(const char* name, int pos) {
-    return new (zone_) Literal(zone_, ast_value_factory_->NewSymbol(name), pos);
+    return new (local_zone_)
+        Literal(local_zone_, ast_value_factory_->NewSymbol(name), pos);
   }
 
   Literal* NewNumberLiteral(double number, int pos, bool with_dot = false) {
-    return new (zone_)
-        Literal(zone_, ast_value_factory_->NewNumber(number, with_dot), pos);
+    return new (local_zone_) Literal(
+        local_zone_, ast_value_factory_->NewNumber(number, with_dot), pos);
   }
 
   Literal* NewSmiLiteral(int number, int pos) {
-    return new (zone_) Literal(zone_, ast_value_factory_->NewSmi(number), pos);
+    return new (local_zone_)
+        Literal(local_zone_, ast_value_factory_->NewSmi(number), pos);
   }
 
   Literal* NewBooleanLiteral(bool b, int pos) {
-    return new (zone_) Literal(zone_, ast_value_factory_->NewBoolean(b), pos);
+    return new (local_zone_)
+        Literal(local_zone_, ast_value_factory_->NewBoolean(b), pos);
   }
 
   Literal* NewNullLiteral(int pos) {
-    return new (zone_) Literal(zone_, ast_value_factory_->NewNull(), pos);
+    return new (local_zone_)
+        Literal(local_zone_, ast_value_factory_->NewNull(), pos);
   }
 
   Literal* NewUndefinedLiteral(int pos) {
-    return new (zone_) Literal(zone_, ast_value_factory_->NewUndefined(), pos);
+    return new (local_zone_)
+        Literal(local_zone_, ast_value_factory_->NewUndefined(), pos);
   }
 
   Literal* NewTheHoleLiteral(int pos) {
-    return new (zone_) Literal(zone_, ast_value_factory_->NewTheHole(), pos);
+    return new (local_zone_)
+        Literal(local_zone_, ast_value_factory_->NewTheHole(), pos);
   }
 
   ObjectLiteral* NewObjectLiteral(
       ZoneList<ObjectLiteral::Property*>* properties, int literal_index,
       uint32_t boilerplate_properties, int pos) {
-    return new (zone_) ObjectLiteral(zone_, properties, literal_index,
-                                     boilerplate_properties, pos);
+    return new (local_zone_) ObjectLiteral(
+        local_zone_, properties, literal_index, boilerplate_properties, pos);
   }
 
   ObjectLiteral::Property* NewObjectLiteralProperty(
       Expression* key, Expression* value, ObjectLiteralProperty::Kind kind,
       bool is_static, bool is_computed_name) {
-    return new (zone_)
+    return new (local_zone_)
         ObjectLiteral::Property(key, value, kind, is_static, is_computed_name);
   }
 
@@ -3237,32 +3250,35 @@
                                                     Expression* value,
                                                     bool is_static,
                                                     bool is_computed_name) {
-    return new (zone_) ObjectLiteral::Property(ast_value_factory_, key, value,
-                                               is_static, is_computed_name);
+    return new (local_zone_) ObjectLiteral::Property(
+        ast_value_factory_, key, value, is_static, is_computed_name);
   }
 
   RegExpLiteral* NewRegExpLiteral(const AstRawString* pattern, int flags,
                                   int literal_index, int pos) {
-    return new (zone_) RegExpLiteral(zone_, pattern, flags, literal_index, pos);
+    return new (local_zone_)
+        RegExpLiteral(local_zone_, pattern, flags, literal_index, pos);
   }
 
   ArrayLiteral* NewArrayLiteral(ZoneList<Expression*>* values,
                                 int literal_index,
                                 int pos) {
-    return new (zone_) ArrayLiteral(zone_, values, -1, literal_index, pos);
+    return new (local_zone_)
+        ArrayLiteral(local_zone_, values, -1, literal_index, pos);
   }
 
   ArrayLiteral* NewArrayLiteral(ZoneList<Expression*>* values,
                                 int first_spread_index, int literal_index,
                                 int pos) {
-    return new (zone_)
-        ArrayLiteral(zone_, values, first_spread_index, literal_index, pos);
+    return new (local_zone_) ArrayLiteral(
+        local_zone_, values, first_spread_index, literal_index, pos);
   }
 
   VariableProxy* NewVariableProxy(Variable* var,
                                   int start_position = kNoSourcePosition,
                                   int end_position = kNoSourcePosition) {
-    return new (zone_) VariableProxy(zone_, var, start_position, end_position);
+    return new (parser_zone_)
+        VariableProxy(parser_zone_, var, start_position, end_position);
   }
 
   VariableProxy* NewVariableProxy(const AstRawString* name,
@@ -3270,89 +3286,87 @@
                                   int start_position = kNoSourcePosition,
                                   int end_position = kNoSourcePosition) {
     DCHECK_NOT_NULL(name);
-    return new (zone_)
-        VariableProxy(zone_, name, variable_kind, start_position, end_position);
-  }
-
-  // Recreates the VariableProxy in this Zone.
-  VariableProxy* CopyVariableProxy(VariableProxy* proxy) {
-    return new (zone_) VariableProxy(zone_, proxy);
+    return new (parser_zone_) VariableProxy(parser_zone_, name, variable_kind,
+                                            start_position, end_position);
   }
 
   Property* NewProperty(Expression* obj, Expression* key, int pos) {
-    return new (zone_) Property(zone_, obj, key, pos);
+    return new (local_zone_) Property(local_zone_, obj, key, pos);
   }
 
   Call* NewCall(Expression* expression,
                 ZoneList<Expression*>* arguments,
                 int pos) {
-    return new (zone_) Call(zone_, expression, arguments, pos);
+    return new (local_zone_) Call(local_zone_, expression, arguments, pos);
   }
 
   CallNew* NewCallNew(Expression* expression,
                       ZoneList<Expression*>* arguments,
                       int pos) {
-    return new (zone_) CallNew(zone_, expression, arguments, pos);
+    return new (local_zone_) CallNew(local_zone_, expression, arguments, pos);
   }
 
   CallRuntime* NewCallRuntime(Runtime::FunctionId id,
                               ZoneList<Expression*>* arguments, int pos) {
-    return new (zone_)
-        CallRuntime(zone_, Runtime::FunctionForId(id), arguments, pos);
+    return new (local_zone_)
+        CallRuntime(local_zone_, Runtime::FunctionForId(id), arguments, pos);
   }
 
   CallRuntime* NewCallRuntime(const Runtime::Function* function,
                               ZoneList<Expression*>* arguments, int pos) {
-    return new (zone_) CallRuntime(zone_, function, arguments, pos);
+    return new (local_zone_) CallRuntime(local_zone_, function, arguments, pos);
   }
 
   CallRuntime* NewCallRuntime(int context_index,
                               ZoneList<Expression*>* arguments, int pos) {
-    return new (zone_) CallRuntime(zone_, context_index, arguments, pos);
+    return new (local_zone_)
+        CallRuntime(local_zone_, context_index, arguments, pos);
   }
 
   UnaryOperation* NewUnaryOperation(Token::Value op,
                                     Expression* expression,
                                     int pos) {
-    return new (zone_) UnaryOperation(zone_, op, expression, pos);
+    return new (local_zone_) UnaryOperation(local_zone_, op, expression, pos);
   }
 
   BinaryOperation* NewBinaryOperation(Token::Value op,
                                       Expression* left,
                                       Expression* right,
                                       int pos) {
-    return new (zone_) BinaryOperation(zone_, op, left, right, pos);
+    return new (local_zone_) BinaryOperation(local_zone_, op, left, right, pos);
   }
 
   CountOperation* NewCountOperation(Token::Value op,
                                     bool is_prefix,
                                     Expression* expr,
                                     int pos) {
-    return new (zone_) CountOperation(zone_, op, is_prefix, expr, pos);
+    return new (local_zone_)
+        CountOperation(local_zone_, op, is_prefix, expr, pos);
   }
 
   CompareOperation* NewCompareOperation(Token::Value op,
                                         Expression* left,
                                         Expression* right,
                                         int pos) {
-    return new (zone_) CompareOperation(zone_, op, left, right, pos);
+    return new (local_zone_)
+        CompareOperation(local_zone_, op, left, right, pos);
   }
 
   Spread* NewSpread(Expression* expression, int pos, int expr_pos) {
-    return new (zone_) Spread(zone_, expression, pos, expr_pos);
+    return new (local_zone_) Spread(local_zone_, expression, pos, expr_pos);
   }
 
   Conditional* NewConditional(Expression* condition,
                               Expression* then_expression,
                               Expression* else_expression,
                               int position) {
-    return new (zone_) Conditional(zone_, condition, then_expression,
-                                   else_expression, position);
+    return new (local_zone_) Conditional(
+        local_zone_, condition, then_expression, else_expression, position);
   }
 
   RewritableExpression* NewRewritableExpression(Expression* expression) {
     DCHECK_NOT_NULL(expression);
-    return new (zone_) RewritableExpression(zone_, expression);
+    return new (local_zone_) RewritableExpression(local_zone_, expression);
   }
 
   Assignment* NewAssignment(Token::Value op,
@@ -3360,7 +3374,8 @@
                             Expression* value,
                             int pos) {
     DCHECK(Token::IsAssignmentOp(op));
-    Assignment* assign = new (zone_) Assignment(zone_, op, target, value, pos);
+    Assignment* assign =
+        new (local_zone_) Assignment(local_zone_, op, target, value, pos);
     if (assign->is_compound()) {
       DCHECK(Token::IsAssignmentOp(op));
       assign->binary_operation_ =
@@ -3372,12 +3387,12 @@
   Yield* NewYield(Expression* generator_object, Expression* expression, int pos,
                   Yield::OnException on_exception) {
     if (!expression) expression = NewUndefinedLiteral(pos);
-    return new (zone_)
-        Yield(zone_, generator_object, expression, pos, on_exception);
+    return new (local_zone_)
+        Yield(local_zone_, generator_object, expression, pos, on_exception);
   }
 
   Throw* NewThrow(Expression* exception, int pos) {
-    return new (zone_) Throw(zone_, exception, pos);
+    return new (local_zone_) Throw(local_zone_, exception, pos);
   }
 
   FunctionLiteral* NewFunctionLiteral(
@@ -3388,8 +3403,8 @@
       FunctionLiteral::FunctionType function_type,
       FunctionLiteral::EagerCompileHint eager_compile_hint, FunctionKind kind,
       int position) {
-    return new (zone_) FunctionLiteral(
-        zone_, name, ast_value_factory_, scope, body,
+    return new (local_zone_) FunctionLiteral(
+        local_zone_, name, ast_value_factory_, scope, body,
         materialized_literal_count, expected_property_count, parameter_count,
         function_type, has_duplicate_parameters, eager_compile_hint, kind,
         position, true);
@@ -3401,9 +3416,9 @@
   FunctionLiteral* NewScriptOrEvalFunctionLiteral(
       Scope* scope, ZoneList<Statement*>* body, int materialized_literal_count,
       int expected_property_count) {
-    return new (zone_) FunctionLiteral(
-        zone_, ast_value_factory_->empty_string(), ast_value_factory_, scope,
-        body, materialized_literal_count, expected_property_count, 0,
+    return new (local_zone_) FunctionLiteral(
+        local_zone_, ast_value_factory_->empty_string(), ast_value_factory_,
+        scope, body, materialized_literal_count, expected_property_count, 0,
         FunctionLiteral::kAnonymousExpression,
         FunctionLiteral::kNoDuplicateParameters,
         FunctionLiteral::kShouldLazyCompile, FunctionKind::kNormalFunction, 0,
@@ -3414,58 +3429,59 @@
                                 FunctionLiteral* constructor,
                                 ZoneList<ObjectLiteral::Property*>* properties,
                                 int start_position, int end_position) {
-    return new (zone_) ClassLiteral(zone_, proxy, extends, constructor,
-                                    properties, start_position, end_position);
+    return new (local_zone_)
+        ClassLiteral(local_zone_, proxy, extends, constructor, properties,
+                     start_position, end_position);
   }
 
   NativeFunctionLiteral* NewNativeFunctionLiteral(const AstRawString* name,
                                                   v8::Extension* extension,
                                                   int pos) {
-    return new (zone_) NativeFunctionLiteral(zone_, name, extension, pos);
+    return new (local_zone_)
+        NativeFunctionLiteral(local_zone_, name, extension, pos);
   }
 
   DoExpression* NewDoExpression(Block* block, Variable* result_var, int pos) {
     VariableProxy* result = NewVariableProxy(result_var, pos);
-    return new (zone_) DoExpression(zone_, block, result, pos);
+    return new (local_zone_) DoExpression(local_zone_, block, result, pos);
   }
 
   ThisFunction* NewThisFunction(int pos) {
-    return new (zone_) ThisFunction(zone_, pos);
+    return new (local_zone_) ThisFunction(local_zone_, pos);
   }
 
   SuperPropertyReference* NewSuperPropertyReference(VariableProxy* this_var,
                                                     Expression* home_object,
                                                     int pos) {
-    return new (zone_)
-        SuperPropertyReference(zone_, this_var, home_object, pos);
+    return new (local_zone_)
+        SuperPropertyReference(local_zone_, this_var, home_object, pos);
   }
 
   SuperCallReference* NewSuperCallReference(VariableProxy* this_var,
                                             VariableProxy* new_target_var,
                                             VariableProxy* this_function_var,
                                             int pos) {
-    return new (zone_) SuperCallReference(zone_, this_var, new_target_var,
-                                          this_function_var, pos);
+    return new (local_zone_) SuperCallReference(
+        local_zone_, this_var, new_target_var, this_function_var, pos);
   }
 
   EmptyParentheses* NewEmptyParentheses(int pos) {
-    return new (zone_) EmptyParentheses(zone_, pos);
-  }
-
-  Zone* zone() const { return zone_; }
-  void set_zone(Zone* zone) { zone_ = zone; }
+    return new (local_zone_) EmptyParentheses(local_zone_, pos);
+  }
+
+  Zone* zone() const { return local_zone_; }
 
   // Handles use of temporary zones when parsing inner function bodies.
   class BodyScope {
    public:
     BodyScope(AstNodeFactory* factory, Zone* temp_zone, bool use_temp_zone)
-        : factory_(factory), prev_zone_(factory->zone_) {
+        : factory_(factory), prev_zone_(factory->local_zone_) {
       if (use_temp_zone) {
-        factory->zone_ = temp_zone;
+        factory->local_zone_ = temp_zone;
       }
     }
 
-    ~BodyScope() { factory_->zone_ = prev_zone_; }
+    ~BodyScope() { factory_->local_zone_ = prev_zone_; }
 
    private:
     AstNodeFactory* factory_;
@@ -3477,7 +3493,10 @@
   // which we can guarantee is not going to be compiled or have its AST
   // inspected.
   // See ParseFunctionLiteral in parser.cc for preconditions.
-  Zone* zone_;
+  Zone* local_zone_;
+  // ZoneObjects which need to persist until scope analysis must be allocated in
+  // the parser-level zone.
+  Zone* parser_zone_;
   AstValueFactory* ast_value_factory_;
 };