[parser] Skipping inner funcs: make the flag experimental.

The feature is not quite ready for getting ClusterFuzzed.

BUG=v8:5516

Change-Id: I90a42f950727c8ecf46cb2987c9a459b2ba1f5a7
Reviewed-on: https://chromium-review.googlesource.com/480400
Commit-Queue: Marja Hölttä <marja@chromium.org>
Reviewed-by: Daniel Vogelheim <vogelheim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44693}

src/ast/scopes.cc

@@ -612,7 +612,7 @@ void DeclarationScope::HoistSloppyBlockFunctions(AstNodeFactory* factory) {
       Variable* var = DeclareVariableName(name, VAR);
       if (var != kDummyPreParserVariable &&
           var != kDummyPreParserLexicalVariable) {
-        DCHECK(FLAG_preparser_scope_analysis);
+        DCHECK(FLAG_experimental_preparser_scope_analysis);
         var->set_maybe_assigned();
       }
     }
@@ -662,7 +662,7 @@ void DeclarationScope::Analyze(ParseInfo* info, Isolate* isolate,
   scope->set_should_eager_compile();
 
   if (scope->must_use_preparsed_scope_data_) {
-    DCHECK(FLAG_preparser_scope_analysis);
+    DCHECK(FLAG_experimental_preparser_scope_analysis);
     DCHECK_NOT_NULL(info->preparsed_scope_data());
     DCHECK_EQ(scope->scope_type_, ScopeType::FUNCTION_SCOPE);
     info->preparsed_scope_data()->RestoreData(scope);
@@ -1044,7 +1044,7 @@ Variable* DeclarationScope::DeclareParameterName(
   if (name == ast_value_factory->arguments_string()) {
     has_arguments_parameter_ = true;
   }
-  if (FLAG_preparser_scope_analysis) {
+  if (FLAG_experimental_preparser_scope_analysis) {
     Variable* var = Declare(zone(), name, VAR);
     params_.Add(var, zone());
     return var;
@@ -1205,7 +1205,7 @@ Variable* Scope::DeclareVariableName(const AstRawString* name,
   DCHECK(scope_info_.is_null());
 
   // Declare the variable in the declaration scope.
-  if (FLAG_preparser_scope_analysis) {
+  if (FLAG_experimental_preparser_scope_analysis) {
     Variable* var = LookupLocal(name);
     DCHECK_NE(var, kDummyPreParserLexicalVariable);
     DCHECK_NE(var, kDummyPreParserVariable);
@@ -1552,7 +1552,8 @@ void DeclarationScope::AnalyzePartially(
       arguments_ = nullptr;
     }
 
-    if (FLAG_preparser_scope_analysis && preparsed_scope_data->Producing()) {
+    if (FLAG_experimental_preparser_scope_analysis &&
+        preparsed_scope_data->Producing()) {
       // Store the information needed for allocating the locals of this scope
       // and its inner scopes.
       preparsed_scope_data->SaveData(this);
@@ -2257,7 +2258,8 @@ void ModuleScope::AllocateModuleVariables() {
 
 void Scope::AllocateVariablesRecursively() {
   DCHECK(!already_resolved_);
-  DCHECK_IMPLIES(!FLAG_preparser_scope_analysis, num_stack_slots_ == 0);
+  DCHECK_IMPLIES(!FLAG_experimental_preparser_scope_analysis,
+                 num_stack_slots_ == 0);
 
   // Don't allocate variables of preparsed scopes.
   if (is_declaration_scope() && AsDeclarationScope()->was_lazily_parsed()) {

src/compiler.cc

@@ -1082,7 +1082,7 @@ MaybeHandle<Code> GetLazyCode(Handle<JSFunction> function) {
   ParseInfo parse_info(handle(function->shared()));
   Zone compile_zone(isolate->allocator(), ZONE_NAME);
   CompilationInfo info(&compile_zone, &parse_info, isolate, function);
-  if (FLAG_preparser_scope_analysis) {
+  if (FLAG_experimental_preparser_scope_analysis) {
     Handle<SharedFunctionInfo> shared(function->shared());
     Handle<Script> script(Script::cast(function->shared()->script()));
     if (script->HasPreparsedScopeData()) {
@@ -1181,7 +1181,7 @@ Handle<SharedFunctionInfo> CompileToplevel(CompilationInfo* info) {
 
     if (!script.is_null()) {
       script->set_compilation_state(Script::COMPILATION_STATE_COMPILED);
-      if (FLAG_preparser_scope_analysis) {
+      if (FLAG_experimental_preparser_scope_analysis) {
         Handle<FixedUint32Array> data(
             parse_info->preparsed_scope_data()->Serialize(isolate));
         script->set_preparsed_scope_data(*data);

src/flag-definitions.h

@@ -945,9 +945,9 @@ DEFINE_BOOL(lazy_inner_functions, true, "enable lazy parsing inner functions")
 DEFINE_BOOL(aggressive_lazy_inner_functions, false,
             "even lazier inner function parsing")
 DEFINE_IMPLICATION(aggressive_lazy_inner_functions, lazy_inner_functions)
-DEFINE_BOOL(preparser_scope_analysis, false,
+DEFINE_BOOL(experimental_preparser_scope_analysis, false,
             "perform scope analysis for preparsed inner functions")
-DEFINE_IMPLICATION(preparser_scope_analysis, lazy_inner_functions)
+DEFINE_IMPLICATION(experimental_preparser_scope_analysis, lazy_inner_functions)
 
 // simulator-arm.cc, simulator-arm64.cc and simulator-mips.cc
 DEFINE_BOOL(trace_sim, false, "Trace simulator execution")

src/parsing/parser.cc

@@ -2860,7 +2860,7 @@ Parser::LazyParsingResult Parser::SkipFunction(FunctionKind kind,
 
   // FIXME(marja): There are 3 ways to skip functions now. Unify them.
   if (preparsed_scope_data_->Consuming()) {
-    DCHECK(FLAG_preparser_scope_analysis);
+    DCHECK(FLAG_experimental_preparser_scope_analysis);
     const PreParseData::FunctionData& data =
         preparsed_scope_data_->FindFunction(function_scope->start_position());
     if (data.is_valid()) {

src/parsing/preparser.cc

@@ -215,7 +215,8 @@ PreParser::PreParseResult PreParser::PreParseFunction(
     // function var since the arguments object masks 'function arguments'.
     function_scope->DeclareArguments(ast_value_factory());
 
-    if (FLAG_preparser_scope_analysis && preparsed_scope_data_ != nullptr) {
+    if (FLAG_experimental_preparser_scope_analysis &&
+        preparsed_scope_data_ != nullptr) {
       preparsed_scope_data_->AddFunction(
           scope()->start_position(),
           PreParseData::FunctionData(
@@ -354,7 +355,8 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
     }
   }
 
-  if (FLAG_preparser_scope_analysis && preparsed_scope_data_ != nullptr) {
+  if (FLAG_experimental_preparser_scope_analysis &&
+      preparsed_scope_data_ != nullptr) {
     preparsed_scope_data_->AddFunction(
         start_position,
         PreParseData::FunctionData(
@@ -416,7 +418,7 @@ void PreParser::DeclareAndInitializeVariables(
       declaration_descriptor->scope->RemoveUnresolved(variable);
       Variable* var = scope()->DeclareVariableName(
           variable->raw_name(), declaration_descriptor->mode);
-      if (FLAG_preparser_scope_analysis) {
+      if (FLAG_experimental_preparser_scope_analysis) {
         MarkLoopVariableAsAssigned(declaration_descriptor->scope, var);
         // This is only necessary if there is an initializer, but we don't have
         // that information here.  Consequently, the preparser sometimes says

test/cctest/parsing/test-preparser.cc

@@ -28,7 +28,7 @@ enum SkipTests {
 
 TEST(PreParserScopeAnalysis) {
   i::FLAG_lazy_inner_functions = true;
-  i::FLAG_preparser_scope_analysis = true;
+  i::FLAG_experimental_preparser_scope_analysis = true;
   i::Isolate* isolate = CcTest::i_isolate();
   i::Factory* factory = isolate->factory();
   i::HandleScope scope(isolate);

test/mjsunit/skipping-inner-functions.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --preparser-scope-analysis
+// Flags: --experimental-preparser-scope-analysis
 
 (function TestBasicSkipping() {
   var result = 0;