Need Lua portable byte code between architectures?

["=?gb18030?b?1PjA2g==?=" <tech@...>]

hi all,
    now, more than more apps need cross architectures.

such as:
    iOS8's ipa:  must have tow architectures support.
    armv7, armv7s, arm64

    Why not design goal of Lua portable byte code between architectures?

I'm sorry that I weak at English.

Thx