The extra registers and other advancements in instruction sets help a lot. x86 has some enchancements, but if you think that 64-bit is bad for mobile, I strong

The extra registers and other advancements in instruction sets help a lot. x86 has some enchancements, but if you think that 64-bit is bad for mobile, I strongly suggest looking at the A7 32 vs 64 benchmarks. ( http://anandtech.com/show/7335/the-iphone-5s-review/4 http://anandtech.com/show/7335/the-iphone-5s-review/4 ) Of course, the performance gains have really nothing to do with 64-bit addressing alone, but ARM took the opportunity to almost completely redesign the ISA, and A64 is in general a better and faster ISA than A32. So all else is not equal.