Redirect most NewUnresolved calls over Parser

src/parsing/parser.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 "src/parsing/parser.h"
 
 #include <memory>
 
 #include "src/api.h"
 #include "src/ast/ast.h"
@@ skipping 257 matching lines @@
       auto constructor_args_name = ast_value_factory()->empty_string();
       bool is_duplicate;
       bool is_rest = true;
       bool is_optional = false;
       Variable* constructor_args = function_scope->DeclareParameter(
           constructor_args_name, TEMPORARY, is_optional, is_rest, &is_duplicate,
           ast_value_factory());
 
       ZoneList<Expression*>* args =
           new (zone()) ZoneList<Expression*>(2, zone());
-      VariableProxy* this_function_proxy = this->scope()->NewUnresolved(
-          factory(), ast_value_factory()->this_function_string(),
-          Variable::NORMAL, pos);
+      VariableProxy* this_function_proxy =
+          NewUnresolved(ast_value_factory()->this_function_string(), pos);
       ZoneList<Expression*>* tmp =
           new (zone()) ZoneList<Expression*>(1, zone());
       tmp->Add(this_function_proxy, zone());
       Expression* super_constructor = factory()->NewCallRuntime(
           Runtime::kInlineGetSuperConstructor, tmp, pos);
       args->Add(super_constructor, zone());
       Spread* spread_args = factory()->NewSpread(
           factory()->NewVariableProxy(constructor_args), pos, pos);
       ZoneList<Expression*>* spread_args_expr =
           new (zone()) ZoneList<Expression*>(1, zone());
       spread_args_expr->Add(spread_args, zone());
       args->AddAll(*PrepareSpreadArguments(spread_args_expr), zone());
-      VariableProxy* new_target_proxy = this->scope()->NewUnresolved(
-          factory(), ast_value_factory()->new_target_string(), Variable::NORMAL,
-          pos);
+      VariableProxy* new_target_proxy =
+          NewUnresolved(ast_value_factory()->new_target_string(), pos);
       args->Add(new_target_proxy, zone());
       CallRuntime* call = factory()->NewCallRuntime(
           Context::REFLECT_CONSTRUCT_INDEX, args, pos);
       body->Add(factory()->NewReturnStatement(call, pos), zone());
     }
 
     materialized_literal_count = function_state.materialized_literal_count();
     expected_property_count = function_state.expected_property_count();
   }
 
@@ skipping 377 matching lines @@
   char array[100];
   const char* string = DoubleToCString(double_value, ArrayVector(array));
   return parser_->ast_value_factory()->GetOneByteString(string);
 }
 
 
 const AstRawString* ParserTraits::GetNextSymbol(Scanner* scanner) {
   return parser_->scanner()->NextSymbol(parser_->ast_value_factory());
 }
 
-Expression* ParserTraits::ThisExpression(AstNodeFactory* factory, int pos) {
-  return parser_->scope()->NewUnresolved(
-      factory, parser_->ast_value_factory()->this_string(), Variable::THIS, pos,
-      pos + 4);
+Expression* ParserTraits::ThisExpression(int pos) {
+  return parser_->NewUnresolved(parser_->ast_value_factory()->this_string(),
+                                pos, pos + 4, Variable::THIS);
 }
 
 Expression* ParserTraits::NewSuperPropertyReference(AstNodeFactory* factory,
                                                     int pos) {
   // this_function[home_object_symbol]
-  VariableProxy* this_function_proxy = parser_->scope()->NewUnresolved(
-      factory, parser_->ast_value_factory()->this_function_string(),
-      Variable::NORMAL, pos);
+  VariableProxy* this_function_proxy = parser_->NewUnresolved(
+      parser_->ast_value_factory()->this_function_string(), pos);
   Expression* home_object_symbol_literal =
       factory->NewSymbolLiteral("home_object_symbol", kNoSourcePosition);
   Expression* home_object = factory->NewProperty(
       this_function_proxy, home_object_symbol_literal, pos);
   return factory->NewSuperPropertyReference(
-      ThisExpression(factory, pos)->AsVariableProxy(), home_object, pos);
+      ThisExpression(pos)->AsVariableProxy(), home_object, pos);
 }
 
 Expression* ParserTraits::NewSuperCallReference(AstNodeFactory* factory,
                                                 int pos) {
-  VariableProxy* new_target_proxy = parser_->scope()->NewUnresolved(
-      factory, parser_->ast_value_factory()->new_target_string(),
-      Variable::NORMAL, pos);
-  VariableProxy* this_function_proxy = parser_->scope()->NewUnresolved(
-      factory, parser_->ast_value_factory()->this_function_string(),
-      Variable::NORMAL, pos);
-  return factory->NewSuperCallReference(
-      ThisExpression(factory, pos)->AsVariableProxy(), new_target_proxy,
-      this_function_proxy, pos);
+  VariableProxy* new_target_proxy = parser_->NewUnresolved(
+      parser_->ast_value_factory()->new_target_string(), pos);
+  VariableProxy* this_function_proxy = parser_->NewUnresolved(
+      parser_->ast_value_factory()->this_function_string(), pos);
+  return factory->NewSuperCallReference(ThisExpression(pos)->AsVariableProxy(),
+                                        new_target_proxy, this_function_proxy,
+                                        pos);
 }
 
-Expression* ParserTraits::NewTargetExpression(AstNodeFactory* factory,
-                                              int pos) {
+Expression* ParserTraits::NewTargetExpression(int pos) {
   static const int kNewTargetStringLength = 10;
-  auto proxy = parser_->scope()->NewUnresolved(
-      factory, parser_->ast_value_factory()->new_target_string(),
-      Variable::NORMAL, pos, pos + kNewTargetStringLength);
+  auto proxy =
+      parser_->NewUnresolved(parser_->ast_value_factory()->new_target_string(),
+                             pos, pos + kNewTargetStringLength);
   proxy->set_is_new_target();
   return proxy;
 }
 
 Expression* ParserTraits::FunctionSentExpression(AstNodeFactory* factory,
                                                  int pos) {
   // We desugar function.sent into %_GeneratorGetInputOrDebugPos(generator).
   Zone* zone = parser_->zone();
   ZoneList<Expression*>* args = new (zone) ZoneList<Expression*>(1, zone);
   VariableProxy* generator = factory->NewVariableProxy(
@@ skipping 22 matching lines @@
       bool has_dot = scanner->ContainsDot();
       double value = scanner->DoubleValue();
       return factory->NewNumberLiteral(value, pos, has_dot);
     }
     default:
       DCHECK(false);
   }
   return NULL;
 }
 
-
 Expression* ParserTraits::ExpressionFromIdentifier(const AstRawString* name,
                                                    int start_position,
-                                                   int end_position,
-                                                   AstNodeFactory* factory) {
+                                                   int end_position) {
   if (parser_->fni_ != NULL) parser_->fni_->PushVariableName(name);
-  return parser_->scope()->NewUnresolved(factory, name, Variable::NORMAL,
-                                         start_position, end_position);
+  return parser_->NewUnresolved(name, start_position, end_position);
 }
 
 
 Expression* ParserTraits::ExpressionFromString(int pos, Scanner* scanner,
                                                AstNodeFactory* factory) {
   const AstRawString* symbol = GetSymbol(scanner);
   if (parser_->fni_ != NULL) parser_->fni_->PushLiteralName(symbol);
   return factory->NewStringLiteral(symbol, pos);
 }
 
@@ skipping 1150 matching lines @@
 
     case Token::TRY:
       return ParseTryStatement(ok);
 
     default:
       UNREACHABLE();
       return NULL;
   }
 }
 
+VariableProxy* Parser::NewUnresolved(const AstRawString* name, int begin_pos,
+                                     int end_pos, Variable::Kind kind) {
+  return scope()->NewUnresolved(factory(), name, begin_pos, end_pos, kind);
+}
 
-VariableProxy* Parser::NewUnresolved(const AstRawString* name,
-                                     VariableMode mode) {
-  // If we are inside a function, a declaration of a 'var' variable is a
-  // truly local variable, and the scope of the variable is always the function
-  // scope.
-  // Let/const variables are always added to the immediately enclosing scope.
-  Scope* scope =
-      IsLexicalVariableMode(mode) ? this->scope() : GetDeclarationScope();
-  return scope->NewUnresolved(factory(), name, Variable::NORMAL,
-                              scanner()->location().beg_pos,
-                              scanner()->location().end_pos);
+VariableProxy* Parser::NewUnresolved(const AstRawString* name) {
+  return scope()->NewUnresolved(factory(), name, scanner()->location().beg_pos,
+                                scanner()->location().end_pos);
 }
 
 InitializationFlag Parser::DefaultInitializationFlag(VariableMode mode) {
   DCHECK(IsDeclaredVariableMode(mode));
   return mode == VAR ? kCreatedInitialized : kNeedsInitialization;
 }
 
 Declaration* Parser::DeclareVariable(const AstRawString* name,
                                      VariableMode mode, int pos, bool* ok) {
   return DeclareVariable(name, mode, DefaultInitializationFlag(mode), pos, ok);
 }
 
 Declaration* Parser::DeclareVariable(const AstRawString* name,
                                      VariableMode mode, InitializationFlag init,
                                      int pos, bool* ok) {
   DCHECK_NOT_NULL(name);
-  VariableProxy* proxy = NewUnresolved(name, mode);
+  Scope* scope =
+      IsLexicalVariableMode(mode) ? this->scope() : GetDeclarationScope();

[Toon Verwaest, 2016/08/10 06:47:53]

Now only declarations need to use the mode to choose the scope. Unfortunately
this is also used in the pattern rewriter with random scopes for Declare-target
and declaration-position (descriptor_->scope and descriptor_->hoist_scope).

Moving it closer to the declaration since we've anyway been discussing whether
it makes sense to have unresolved proxies for this case at all.

+  VariableProxy* proxy =
+      scope->NewUnresolved(factory(), name, scanner()->location().beg_pos,
+                           scanner()->location().end_pos);
   Declaration* declaration =
-      factory()->NewVariableDeclaration(proxy, mode, scope(), pos);
+      factory()->NewVariableDeclaration(proxy, mode, this->scope(), pos);
   Declare(declaration, DeclarationDescriptor::NORMAL, init, CHECK_OK);
   return declaration;
 }
 
 Variable* Parser::Declare(Declaration* declaration,
                           DeclarationDescriptor::Kind declaration_kind,
                           InitializationFlag init, bool* ok, Scope* scope) {
   VariableProxy* proxy = declaration->proxy();
   DCHECK(proxy->raw_name() != NULL);
   const AstRawString* name = proxy->raw_name();
@@ skipping 210 matching lines @@
       is_generator ? FunctionKind::kGeneratorFunction
                    : is_async ? FunctionKind::kAsyncFunction
                               : FunctionKind::kNormalFunction,
       pos, FunctionLiteral::kDeclaration, language_mode(), CHECK_OK);
 
   // In ES6, a function behaves as a lexical binding, except in
   // a script scope, or the initial scope of eval or another function.
   VariableMode mode =
       (!scope()->is_declaration_scope() || scope()->is_module_scope()) ? LET
                                                                        : VAR;
-  VariableProxy* proxy = NewUnresolved(variable_name, mode);
+  VariableProxy* proxy = NewUnresolved(variable_name);
   Declaration* declaration =
       factory()->NewFunctionDeclaration(proxy, mode, fun, scope(), pos);
   Declare(declaration, DeclarationDescriptor::NORMAL, kCreatedInitialized,
           CHECK_OK);
   if (names) names->Add(variable_name, zone());
   EmptyStatement* empty = factory()->NewEmptyStatement(kNoSourcePosition);
   // Async functions don't undergo sloppy mode block scoped hoisting, and don't
   // allow duplicates in a block. Both are represented by the
   // sloppy_block_function_map. Don't add them to the map for async functions.
   // Generators are also supposed to be prohibited; currently doing this behind
@@ skipping 487 matching lines @@
   Scanner::Location loc = scanner()->location();
 
   Token::Value tok = peek();
   Statement* result;
   Expression* return_value;
   if (scanner()->HasAnyLineTerminatorBeforeNext() ||
       tok == Token::SEMICOLON ||
       tok == Token::RBRACE ||
       tok == Token::EOS) {
     if (IsSubclassConstructor(function_state_->kind())) {
-      return_value = ThisExpression(factory(), loc.beg_pos);
+      return_value = ThisExpression(loc.beg_pos);
     } else {
       return_value = GetLiteralUndefined(position());
     }
   } else {
     int pos = peek_position();
 
     if (IsSubclassConstructor(function_state_->kind())) {
       // Because of the return code rewriting that happens in case of a subclass
       // constructor we don't want to accept tail calls, therefore we don't set
       // ReturnExprScope to kInsideValidReturnStatement here.
@@ skipping 26 matching lines @@
       Expression* is_object_conditional = factory()->NewConditional(
           is_spec_object_call, factory()->NewVariableProxy(temp),
           factory()->NewSmiLiteral(1, pos), pos);
 
       // temp === undefined
       Expression* is_undefined = factory()->NewCompareOperation(
           Token::EQ_STRICT, assign,
           factory()->NewUndefinedLiteral(kNoSourcePosition), pos);
 
       // is_undefined ? this : is_object_conditional
-      return_value = factory()->NewConditional(is_undefined,
-                                               ThisExpression(factory(), pos),
-                                               is_object_conditional, pos);
+      return_value = factory()->NewConditional(
+          is_undefined, ThisExpression(pos), is_object_conditional, pos);
     } else {
       ReturnExprScope maybe_allow_tail_calls(
           function_state_, ReturnExprContext::kInsideValidReturnStatement);
       return_value = ParseExpression(true, CHECK_OK);
 
       if (allow_tailcalls() && !is_sloppy(language_mode())) {
         // ES6 14.6.1 Static Semantics: IsInTailPosition
         function_state_->AddImplicitTailCallExpression(return_value);
       }
     }
@@ skipping 658 matching lines @@
       factory()->NewBlock(NULL, names->length() + 4, false, kNoSourcePosition);
 
   // Add statement: let/const x = i.
   outer_block->statements()->Add(init, zone());
 
   const AstRawString* temp_name = ast_value_factory()->dot_for_string();
 
   // For each lexical variable x:
   //   make statement: temp_x = x.
   for (int i = 0; i < names->length(); i++) {
-    VariableProxy* proxy = NewUnresolved(names->at(i), LET);
+    VariableProxy* proxy = NewUnresolved(names->at(i));
     Variable* temp = NewTemporary(temp_name);
     VariableProxy* temp_proxy = factory()->NewVariableProxy(temp);
     Assignment* assignment = factory()->NewAssignment(Token::ASSIGN, temp_proxy,
                                                       proxy, kNoSourcePosition);
     Statement* assignment_statement =
         factory()->NewExpressionStatement(assignment, kNoSourcePosition);
     outer_block->statements()->Add(assignment_statement, zone());
     temps.Add(temp, zone());
   }
 
@@ skipping 250 matching lines @@
         bound_names_are_lexical =
             IsLexicalVariableMode(parsing_result.descriptor.mode);
 
         // special case for legacy for (var ... = ... in ...)
         if (!bound_names_are_lexical && decl.pattern->IsVariableProxy() &&
             decl.initializer != nullptr) {
           DCHECK(!allow_harmony_for_in());
           ++use_counts_[v8::Isolate::kForInInitializer];
           const AstRawString* name =
               decl.pattern->AsVariableProxy()->raw_name();
-          VariableProxy* single_var = NewUnresolved(name, VAR);
+          VariableProxy* single_var = NewUnresolved(name);
           init_block = factory()->NewBlock(
               nullptr, 2, true, parsing_result.descriptor.declaration_pos);
           init_block->statements()->Add(
               factory()->NewExpressionStatement(
                   factory()->NewAssignment(Token::ASSIGN, single_var,
                                            decl.initializer, kNoSourcePosition),
                   kNoSourcePosition),
               zone());
         }
 
@@ skipping 1022 matching lines @@
 
   block = factory()->NewBlock(nullptr, 1, true, kNoSourcePosition);
   block->statements()->Add(try_catch_statement, zone());
   return block;
 }
 
 Expression* Parser::BuildCreateJSGeneratorObject(int pos, FunctionKind kind) {
   DCHECK_NOT_NULL(function_state_->generator_object_variable());
   ZoneList<Expression*>* args = new (zone()) ZoneList<Expression*>(2, zone());
   args->Add(factory()->NewThisFunction(pos), zone());
-  args->Add(IsArrowFunction(kind)
-                ? GetLiteralUndefined(pos)
-                : ThisExpression(factory(), kNoSourcePosition),
+  args->Add(IsArrowFunction(kind) ? GetLiteralUndefined(pos)
+                                  : ThisExpression(kNoSourcePosition),
             zone());
   return factory()->NewCallRuntime(Runtime::kCreateJSGeneratorObject, args,
                                    pos);
 }
 
 Expression* Parser::BuildPromiseResolve(Expression* value, int pos) {
   ZoneList<Expression*>* args = new (zone()) ZoneList<Expression*>(1, zone());
   args->Add(value, zone());
   return factory()->NewCallRuntime(Context::PROMISE_CREATE_RESOLVED_INDEX, args,
                                    pos);
@@ skipping 100 matching lines @@
     } else if (IsAsyncFunction(kind)) {
       const bool accept_IN = true;
       DesugarAsyncFunctionBody(function_name, inner_scope, body, nullptr, kind,
                                FunctionBody::Normal, accept_IN, pos, CHECK_OK);
     } else {
       ParseStatementList(body, Token::RBRACE, CHECK_OK);
     }
 
     if (IsSubclassConstructor(kind)) {
       body->Add(factory()->NewReturnStatement(
-                    this->ThisExpression(factory(), kNoSourcePosition),
-                    kNoSourcePosition),
+                    this->ThisExpression(kNoSourcePosition), kNoSourcePosition),
                 zone());
     }
   }
 
   Expect(Token::RBRACE, CHECK_OK);
   scope()->set_end_position(scanner()->location().end_pos);
 
   if (!parameters.is_simple) {
     DCHECK_NOT_NULL(inner_scope);
     DCHECK_EQ(function_scope, scope());
@@ skipping 113 matching lines @@
   }
 
   BlockState block_state(&scope_state_);
   RaiseLanguageMode(STRICT);
 #ifdef DEBUG
   scope()->SetScopeName(name);
 #endif
 
   VariableProxy* proxy = nullptr;
   if (name != nullptr) {
-    proxy = NewUnresolved(name, CONST);
+    proxy = NewUnresolved(name);
     // TODO(verwaest): declare via block_state.
     Declaration* declaration = factory()->NewVariableDeclaration(
         proxy, CONST, block_state.scope(), pos);
     Declare(declaration, DeclarationDescriptor::NORMAL,
             DefaultInitializationFlag(CONST), CHECK_OK);
   }
 
   Expression* extends = nullptr;
   if (Check(Token::EXTENDS)) {
     block_state.set_start_position(scanner()->location().end_pos);
@@ skipping 181 matching lines @@
   Scope* function_scope = inner_scope->outer_scope();
   DCHECK(function_scope->is_function_scope());
   ZoneList<Declaration*>* decls = inner_scope->declarations();
   BlockState block_state(&scope_state_, inner_scope);
   for (int i = 0; i < decls->length(); ++i) {
     Declaration* decl = decls->at(i);
     if (decl->mode() != VAR || !decl->IsVariableDeclaration()) continue;
     const AstRawString* name = decl->proxy()->raw_name();
     Variable* parameter = function_scope->LookupLocal(name);
     if (parameter == nullptr) continue;
-    VariableProxy* to = NewUnresolved(name, VAR);
+    VariableProxy* to = NewUnresolved(name);
     VariableProxy* from = factory()->NewVariableProxy(parameter);
     Expression* assignment =
         factory()->NewAssignment(Token::ASSIGN, to, from, kNoSourcePosition);
     Statement* statement =
         factory()->NewExpressionStatement(assignment, kNoSourcePosition);
     inner_block->statements()->InsertAt(0, statement, zone());
   }
 }
 
 void Parser::InsertSloppyBlockFunctionVarBindings(DeclarationScope* scope,
@@ skipping 461 matching lines @@
     Expression* super_constructor = factory()->NewCallRuntime(
         Runtime::kInlineGetSuperConstructor, tmp, pos);
     args->InsertAt(0, super_constructor, zone());
     args->Add(function->AsSuperCallReference()->new_target_var(), zone());
     return factory()->NewCallRuntime(Context::REFLECT_CONSTRUCT_INDEX, args,
                                      pos);
   } else {
     if (function->IsProperty()) {
       // Method calls
       if (function->AsProperty()->IsSuperAccess()) {
-        Expression* home = ThisExpression(factory(), kNoSourcePosition);
+        Expression* home = ThisExpression(kNoSourcePosition);
         args->InsertAt(0, function, zone());
         args->InsertAt(1, home, zone());
       } else {
         Variable* temp = NewTemporary(ast_value_factory()->empty_string());
         VariableProxy* obj = factory()->NewVariableProxy(temp);
         Assignment* assign_obj = factory()->NewAssignment(
             Token::ASSIGN, obj, function->AsProperty()->obj(),
             kNoSourcePosition);
         function = factory()->NewProperty(
             assign_obj, function->AsProperty()->key(), kNoSourcePosition);
@@ skipping 220 matching lines @@
 
 Expression* Parser::RewriteAssignExponentiation(Expression* left,
                                                 Expression* right, int pos) {
   ZoneList<Expression*>* args = new (zone()) ZoneList<Expression*>(2, zone());
   if (left->IsVariableProxy()) {
     VariableProxy* lhs = left->AsVariableProxy();
 
     Expression* result;
     DCHECK_NOT_NULL(lhs->raw_name());
     result = this->ExpressionFromIdentifier(lhs->raw_name(), lhs->position(),
-                                            lhs->end_position(), factory());
+                                            lhs->end_position());
     args->Add(left, zone());
     args->Add(right, zone());
     Expression* call =
         factory()->NewCallRuntime(Context::MATH_POW_INDEX, args, pos);
     return factory()->NewAssignment(Token::ASSIGN, result, call, pos);
   } else if (left->IsProperty()) {
     Property* prop = left->AsProperty();
     auto temp_obj = NewTemporary(ast_value_factory()->empty_string());
     auto temp_key = NewTemporary(ast_value_factory()->empty_string());
     Expression* assign_obj = factory()->NewAssignment(
@@ skipping 1134 matching lines @@
   node->Print(Isolate::Current());
 }
 #endif  // DEBUG
 
 #undef CHECK_OK
 #undef CHECK_OK_VOID
 #undef CHECK_FAILED
 
 }  // namespace internal
 }  // namespace v8