What Benefits Does the iPhone 5S Get From Being 64-bit?
That means, for instance, that Anand’s comparison on the same hardware of two versions of Geekbench: the one just before and the one just after addition of ARM64 support, while clever and the best he could do, is not really a fair comparison of ARM64v8 and ARM32v8, but in fact a comparison between ARM64v8 and ARMv7. When you remove the impressive AES and SHA1 advantages from the comparison table, you end up with something that may be fair, though it’s still hard to know for sure.
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I’m not going to conclude one way or the other: neither that the 64-bit aspect of the iPhone 5S is a marketing gimmick, or that it is everything Apple implied it would be. I won’t enter this game. Because what I do see here is the result of awesome work from both the processor side, the OS side, and the toolchain side at Apple to seamlessly get us a full 64-bit ARM environment (with 32-bit compatibility) all at once, without us having to double-guess the next increment. The shorter the transition, the better we’ll all be, and Apple couldn’t do shorter than that.
