tree 4102f92df6687f6fbdb7b571acbc020f227c0b58
parent 48bc94253fa4e8aaa69a1c11f195b729ff427729
author littledan <littledan@chromium.org> 1452133790 -0800
committer Commit bot <commit-bot@chromium.org> 1452133801 +0000

Add Array support for @@species and subclassing

This patch implements @@species, guarded behind the --harmony-species
flag, on Arrays. Methods which return an Array will instead return
the appropriate instance based on the ArraySpeciesCreate algorithm.
The algorithm is implemented in C++ to get access to realm information
and to implement some Array methods in C++, but it is also accessed
from JavaScript through a new runtime function. A couple interactive
Octane runs show no performance regression with the flag turned off,
but turning --harmony-species on will surely have a significant
regression, as Array methods now heavily use ObjectDefineProperty.

BUG=v8:4093
LOG=Y
R=adamk,cbruni

Review URL: https://codereview.chromium.org/1560763002

Cr-Commit-Position: refs/heads/master@{#33144}