Revert of Eagerly declare eval scopes, even for sloppy scopes (patchset #2...

Revert of Eagerly declare eval scopes, even for sloppy scopes (patchset #2 id:20001 of https://codereview.chromium.org/1085263003/)

Reason for revert:
Regresses CodeLoad (crbug.com/480774).

Original issue's description:
> Eagerly declare eval scopes, even for sloppy scopes
>
> R=marja@chromium.org, mstarzinger@chromium.org
> LOG=N
> BUG=N
>
> Committed: https://crrev.com/fe9efc121c8cba8b6aee1a9cf36c68ee97c44d99
> Cr-Commit-Position: refs/heads/master@{#28027}

TBR=mstarzinger@chromium.org,verwaest@chromium.org,wingo@igalia.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=N

Review URL: https://codereview.chromium.org/1082013003

Cr-Commit-Position: refs/heads/master@{#28037}

src/parser.cc

@@ -977,7 +977,9 @@ FunctionLiteral* Parser::DoParseProgram(ParseInfo* info) {
     }
     original_scope_ = scope;
     if (info->is_eval()) {
+      if (!scope->is_script_scope() || is_strict(info->language_mode())) {
         scope = NewScope(scope, EVAL_SCOPE);
+      }
     } else if (info->is_module()) {
       scope = NewScope(scope, MODULE_SCOPE);
     }
@@ -1004,7 +1006,10 @@ FunctionLiteral* Parser::DoParseProgram(ParseInfo* info) {
       DCHECK(allow_harmony_modules());
       ParseModuleItemList(body, &ok);
     } else {
-      ParseStatementList(body, Token::EOS, &ok);
+      Scope* eval_scope = nullptr;
+      ParseStatementList(body, Token::EOS, info->is_eval(), &eval_scope, &ok);
+      if (eval_scope != nullptr)
+        eval_scope->set_end_position(scanner()->peek_location().beg_pos);
     }
 
     // The parser will peek but not consume EOS.  Our scope logically goes all
@@ -1190,7 +1195,7 @@ FunctionLiteral* Parser::ParseLazy(Isolate* isolate, ParseInfo* info,
 
 
 void* Parser::ParseStatementList(ZoneList<Statement*>* body, int end_token,
-                                 bool* ok) {
+                                 bool is_eval, Scope** eval_scope, bool* ok) {
   // StatementList ::
   //   (StatementListItem)* <end_token>
 
@@ -1262,6 +1267,23 @@ void* Parser::ParseStatementList(ZoneList<Statement*>* body, int end_token,
           // Strong mode implies strict mode. If there are several "use strict"
           // / "use strong" directives, do the strict mode changes only once.
           if (is_sloppy(scope_->language_mode())) {
+            // TODO(mstarzinger): Global strict eval calls, need their own scope
+            // as specified in ES5 10.4.2(3). The correct fix would be to always
+            // add this scope in DoParseProgram(), but that requires adaptations
+            // all over the code base, so we go with a quick-fix for now.
+            // In the same manner, we have to patch the parsing mode.
+            if (is_eval && !scope_->is_eval_scope()) {
+              DCHECK(scope_->is_script_scope());
+              Scope* scope = NewScope(scope_, EVAL_SCOPE);
+              scope->set_start_position(scope_->start_position());
+              scope->set_end_position(scope_->end_position());
+              scope_ = scope;
+              if (eval_scope != NULL) {
+                // Caller will correct the positions of the ad hoc eval scope.
+                *eval_scope = scope;
+              }
+              mode_ = PARSE_EAGERLY;
+            }
             scope_->SetLanguageMode(static_cast<LanguageMode>(
                 scope_->language_mode() | STRICT_BIT));
           }
@@ -4249,7 +4271,7 @@ ZoneList<Statement*>* Parser::ParseEagerFunctionBody(
         yield, RelocInfo::kNoPosition), zone());
   }
 
-  ParseStatementList(body, Token::RBRACE, CHECK_OK);
+  ParseStatementList(body, Token::RBRACE, false, NULL, CHECK_OK);
 
   if (IsGeneratorFunction(kind)) {
     VariableProxy* get_proxy = factory()->NewVariableProxy(

src/parser.h

@@ -910,7 +910,8 @@ class Parser : public ParserBase<ParserTraits> {
   // which is set to false if parsing failed; it is unchanged otherwise.
   // By making the 'exception handling' explicit, we are forced to check
   // for failure at the call sites.
-  void* ParseStatementList(ZoneList<Statement*>* body, int end_token, bool* ok);
+  void* ParseStatementList(ZoneList<Statement*>* body, int end_token,
+                           bool is_eval, Scope** ad_hoc_eval_scope, bool* ok);
   Statement* ParseStatementListItem(bool* ok);
   void* ParseModuleItemList(ZoneList<Statement*>* body, bool* ok);
   Statement* ParseModuleItem(bool* ok);

src/runtime/runtime-scopes.cc

@@ -240,17 +240,12 @@ RUNTIME_FUNCTION(Runtime_DeclareLookupSlot) {
 
   // TODO(verwaest): This case should probably not be covered by this function,
   // but by DeclareGlobals instead.
-  if (attributes != ABSENT && holder->IsJSGlobalObject()) {
+  if ((attributes != ABSENT && holder->IsJSGlobalObject()) ||
+      (context_arg->has_extension() &&
+       context_arg->extension()->IsJSGlobalObject())) {
     return DeclareGlobals(isolate, Handle<JSGlobalObject>::cast(holder), name,
                           value, attr, is_var, is_const, is_function);
   }
-  if (context_arg->has_extension() &&
-      context_arg->extension()->IsJSGlobalObject()) {
-    Handle<JSGlobalObject> global(
-        JSGlobalObject::cast(context_arg->extension()), isolate);
-    return DeclareGlobals(isolate, global, name, value, attr, is_var, is_const,
-                          is_function);
-  }
 
   if (attributes != ABSENT) {
     // The name was declared before; check for conflicting re-declarations.