It is worth noting that this is likely to be an iOS-on-AArch64 specific tweak. Apple doesn't do this on x64 OS X (right?). Furthermore, nothing has been said (

It is worth noting that this is likely to be an iOS-on-AArch64 specific tweak. Apple doesn't do this on x64 OS X (right?). Furthermore, nothing has been said (AFAIK) about similar tricks Google is doing with Android on AArch64 or 64 bit architectures in general. From what I've heard they just made the Android runtime capable of emitting AArch64 (and x64, MIPS64) instructions instead of 32-bit ARMv7 ones. That alone gives plenty of a performance boost as AArch64 instructions are supposedly quite a bit faster than the old 32-bit ones. It remains to be seen though whether Google can make as much use of clever allocation tricks as much as Apple can: Android is much more platform agnostic and uses a garbage collector for some of these tasks.