[elements] Precisely estimate elements size for large-object limits

src/factory.h

 // Copyright 2014 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.
 
 #ifndef V8_FACTORY_H_
 #define V8_FACTORY_H_
 
 #include "src/globals.h"
 #include "src/isolate.h"
 #include "src/messages.h"
@@ skipping 13 matching lines @@
 // Interface for handle based allocation.
 class V8_EXPORT_PRIVATE Factory final {
  public:
   Handle<Oddball> NewOddball(Handle<Map> map, const char* to_string,
                              Handle<Object> to_number, const char* type_of,
                              byte kind);
 
   // Allocates a fixed array initialized with undefined values.
   Handle<FixedArray> NewFixedArray(int size,
                                    PretenureFlag pretenure = NOT_TENURED);
+  // Tries allocating a fixed array initialized with undefined values.
+  // In case of an allocation failure (OOM) an empty handle is returned.
+  // The caller has to manually signal an
+  // v8::internal::Heap::FatalProcessOutOfMemory typically by calling
+  // NewFixedArray as a fallback.
+  MUST_USE_RESULT
+  MaybeHandle<FixedArray> TryNewFixedArray(
+      int size, PretenureFlag pretenure = NOT_TENURED);
 
   // Allocate a new fixed array with non-existing entries (the hole).
   Handle<FixedArray> NewFixedArrayWithHoles(
       int size,
       PretenureFlag pretenure = NOT_TENURED);
 
   // Allocates an uninitialized fixed array. It must be filled by the caller.
   Handle<FixedArray> NewUninitializedFixedArray(int size);
 
   // Allocate a new uninitialized fixed double array.
@@ skipping 744 matching lines @@
                                      FunctionMode function_mode);
 
   void SetStrictFunctionInstanceDescriptor(Handle<Map> map,
                                            FunctionMode function_mode);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_FACTORY_H_