Reland: [Compiler] Enable handles created during parsing and scope analysis to be deferred.

src/compilation-info.cc

 // Copyright 2016 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/compilation-info.h"
 
 #include "src/api.h"
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/debug/debug.h"
@@ skipping 89 matching lines @@
       parameter_count_(0),
       optimization_id_(-1),
       osr_expr_stack_height_(-1),
       debug_name_(debug_name) {}
 
 CompilationInfo::~CompilationInfo() {
   if (GetFlag(kDisableFutureOptimization) && has_shared_info()) {
     shared_info()->DisableOptimization(bailout_reason());
   }
   dependencies()->Rollback();
-  delete deferred_handles_;
 }
 
 int CompilationInfo::num_parameters() const {
   return !IsStub() ? scope()->num_parameters() : parameter_count_;
 }
 
 int CompilationInfo::num_parameters_including_this() const {
   return num_parameters() + (is_this_defined() ? 1 : 0);
 }
 
 bool CompilationInfo::is_this_defined() const { return !IsStub(); }
 
 // Primitive functions are unlikely to be picked up by the stack-walking
 // profiler, so they trigger their own optimization when they're called
 // for the SharedFunctionInfo::kCallsUntilPrimitiveOptimization-th time.
 bool CompilationInfo::ShouldSelfOptimize() {
   return FLAG_opt && FLAG_crankshaft &&
          !(literal()->flags() & AstProperties::kDontSelfOptimize) &&
          !literal()->dont_optimize() &&
          literal()->scope()->AllowsLazyCompilation() &&
          !shared_info()->optimization_disabled();
 }
 
+void CompilationInfo::set_deferred_handles(
+    std::shared_ptr<DeferredHandles> deferred_handles) {
+  DCHECK(deferred_handles_.get() == nullptr);
+  deferred_handles_.swap(deferred_handles);
+}
+
+void CompilationInfo::set_deferred_handles(DeferredHandles* deferred_handles) {
+  DCHECK(deferred_handles_.get() == nullptr);
+  deferred_handles_.reset(deferred_handles);
+}
+
 void CompilationInfo::ReopenHandlesInNewHandleScope() {
-  closure_ = Handle<JSFunction>(*closure_);
+  if (!closure_.is_null()) {
+    closure_ = Handle<JSFunction>(*closure_);
+  }
 }
 
 bool CompilationInfo::has_simple_parameters() {
   return scope()->has_simple_parameters();
 }
 
 std::unique_ptr<char[]> CompilationInfo::GetDebugName() const {
   if (parse_info() && parse_info()->literal()) {
     AllowHandleDereference allow_deref;
     return parse_info()->literal()->debug_name()->ToCString();
@@ skipping 85 matching lines @@
       inlined_function, handle(inlined_function->code()), pos));
   return id;
 }
 
 Code::Kind CompilationInfo::output_code_kind() const {
   return Code::ExtractKindFromFlags(code_flags_);
 }
 
 }  // namespace internal
 }  // namespace v8