How is the iPhone 5 armv7s processor different from its predecessors?

Question

The iPhone 5 is the first Apple device with armv7s processors.

Is the instruction set identical?

What about backwards compatibility? Will the iPhone 5 be able to run apps compiled for the armv6 and armv7 architectures?

Gilbye

the armv7 has been in use since the iPhone 3GS – Camilacamile

its still in the same generation though. To answer your other question though: No, because the new Xcode wont support armv6 – Camilacamile

armv7s is probably the name of the instruction set, at least for the purposes of clang. The name of the processor is Apple A6. Otherwise, not much for certain can be said about it: arstechnica.com/apple/2012/09/… – Enjoy

Thanks for the link. Yes, but I chose to write "armv7s processor" instead of "processor supporting armv7s instruction set". – Gilbye

Answer 1

AnandTech has an analysis of the new CPU: http://www.anandtech.com/show/6292/iphone-5-a6-not-a15-custom-core

The main difference is apparently that ARMv7s has VFPv4 support (but you should read the full article, it's very thorough).

The cpu is backwards compatible, it will be able to execute apps compiled for both ARMv6 and ARMv7.

Pallaton

Answer 2

This may not be a different processor at all. They may have just started compiling everything for a new mode that has a different ABI. In the Linux world they're doing a similar transition with the move to hard-float (arm7hf).

Isogamete