Track allocation info

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 374e54c97389e448721421ca80898aeb6d42df1d..10623fb59db1ef8268f0c662a551f296b64bfefd 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -7747,6 +7747,10 @@ static bool IsAllocationInlineable(Handle<JSFunction> constructor) {
       constructor->initial_map()->instance_size() < HAllocateObject::kMaxSize;
 }
 
+static bool IsArrayConstructInlinable(Handle<JSFunction> constructor) {
+  return constructor->GetIsolate()->global_context()->array_function() ==
+      *constructor;
+}
 
 void HGraphBuilder::VisitCallNew(CallNew* expr) {
   ASSERT(!HasStackOverflow());
@@ -7795,6 +7799,30 @@ void HGraphBuilder::VisitCallNew(CallNew* expr) {
         new(zone()) HCallNew(context, function, argument_count));
     call->set_position(expr->position());
     return ast_context()->ReturnInstruction(call, expr->id());
+  } else if (expr->IsMonomorphic() &&
+             argument_count == 1 &&
+             IsArrayConstructInlinable(expr->target())) {
+    CHECK_ALIVE(VisitForValue(expr->expression()));
+    HValue* function = Top();
+    environment()->Drop(1);
+    Handle<JSFunction> constructor = expr->target();
+    ElementsKind elements_kind = expr->elements_kind();
+    AddInstruction(new(zone()) HCheckFunction(function, constructor));
+    Factory* f = graph()->isolate()->factory();
+    Handle<JSArray> boilerplate = f->NewEmptyJSArray(elements_kind, TENURED);
+    HValue* context = environment()->LookupContext();
+    int total_size = JSArray::kSize + FixedArray::kHeaderSize;
+    if (IsFastDoubleElementsKind(elements_kind)) {
+      total_size += boilerplate->elements()->length() * kDoubleSize;
+    } else {
+      total_size += boilerplate->elements()->length() * kPointerSize;
+    }
+    HFastLiteral* empty_array = new(zone()) HFastLiteral(context,
+                                                         boilerplate,
+                                                         total_size,
+                                                         0,
+                                                         0);
+    return ast_context()->ReturnInstruction(empty_array, expr->id());    
   } else {
     // The constructor function is both an operand to the instruction and an
     // argument to the construct call.