Remove unnecessary elements type check when allocating array in runtime.

src/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4343 matching lines @@
   return result;
 }
 
 
 MaybeObject* Heap::AllocateJSArray(
     ElementsKind elements_kind,
     PretenureFlag pretenure) {
   Context* global_context = isolate()->context()->global_context();
   JSFunction* array_function = global_context->array_function();
   Map* map = array_function->initial_map();
-  if (elements_kind == FAST_ELEMENTS || !FLAG_smi_only_arrays) {
+  if (elements_kind == FAST_DOUBLE_ELEMENTS) {
+    map = Map::cast(global_context->double_js_array_map());
+  } else if (elements_kind == FAST_ELEMENTS || !FLAG_smi_only_arrays) {
     map = Map::cast(global_context->object_js_array_map());
-  } else if (elements_kind == FAST_DOUBLE_ELEMENTS) {
-    map = Map::cast(global_context->double_js_array_map());
   } else {
     ASSERT(elements_kind == FAST_SMI_ONLY_ELEMENTS);
     ASSERT(map == global_context->smi_js_array_map());
   }
 
   return AllocateJSObjectFromMap(map, pretenure);
 }
 
 
 MaybeObject* Heap::AllocateEmptyFixedArray() {
@@ skipping 2503 matching lines @@
   isolate_->heap()->store_buffer()->Compact();
   isolate_->heap()->store_buffer()->Filter(MemoryChunk::ABOUT_TO_BE_FREED);
   for (chunk = chunks_queued_for_free_; chunk != NULL; chunk = next) {
     next = chunk->next_chunk();
     isolate_->memory_allocator()->Free(chunk);
   }
   chunks_queued_for_free_ = NULL;
 }
 
 } }  // namespace v8::internal