[ignition] desugar async functions/generators/modules in BytecodeGenerator

src/ast/scopes.cc

Index: src/ast/scopes.cc
diff --git a/src/ast/scopes.cc b/src/ast/scopes.cc
index bd91e16a5220cccfab9ccb59f7eee7464dedac52..4f720b94eadc18a35c587cb9663b8edaff1451ec 100644
--- a/src/ast/scopes.cc
+++ b/src/ast/scopes.cc
@@ -298,6 +298,8 @@ void DeclarationScope::SetDefaults() {
   function_ = nullptr;
   arguments_ = nullptr;
   this_function_ = nullptr;
+  generator_object_ = nullptr;
+  promise_ = nullptr;
   should_eager_compile_ = false;
   was_lazily_parsed_ = false;
 #ifdef DEBUG
@@ -703,6 +705,21 @@ Variable* DeclarationScope::DeclareFunctionVar(const AstRawString* name) {
   return function_;
 }
 
+Variable* DeclarationScope::DeclareGeneratorObjectVar(
+    const AstRawString* name) {
+  DCHECK(is_function_scope() || is_module_scope());
+  DCHECK_NULL(generator_object_);
+  generator_object_ = NewTemporary(name);
+  return generator_object_;
+}
+
+Variable* DeclarationScope::DeclarePromiseVar(const AstRawString* name) {
+  DCHECK(is_function_scope());
+  DCHECK_NULL(promise_);
+  promise_ = NewTemporary(name);
+  return promise_;
+}
+
 bool Scope::HasBeenRemoved() const {
   if (sibling() == this) {
     DCHECK_NULL(inner_scope_);
@@ -1357,6 +1374,19 @@ Scope* Scope::GetOuterScopeWithContext() {
   return scope;
 }
 
+bool Scope::HasLazilyParsedInnerFunctionScope() const {
+  for (Scope* scope = inner_scope_; scope; scope = scope->sibling_) {
+    if (scope->is_function_scope()) {
+      DCHECK(scope->is_declaration_scope_);
+      if (static_cast<DeclarationScope*>(scope)->was_lazily_parsed()) {
+        return true;
+      }
+      if (scope->HasLazilyParsedInnerFunctionScope()) return true;
+    }
+  }
+  return false;
+}
+
 Handle<StringSet> DeclarationScope::CollectNonLocals(
     ParseInfo* info, Handle<StringSet> non_locals) {
   VariableProxy* free_variables = FetchFreeVariables(this, info);