
64 bits. It’s Nothing. You Don’t Need It. And We’ll Have It In 6 Months  - coloneltcb
http://www.mondaynote.com/2013/09/22/64-bits-its-nothing-you-dont-need-it-and-well-have-it-in-6-months/
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kevingadd
I don't understand how you write a post this long and meandering, talking
about how Google will select a 64-bit processor, without even noting the
obvious, fundamental fact that _Apple 's new processor is faster because it's
a new ARM architecture, not because it's 64-bit_. It would probably be faster
if it were 32-bit. Doubling the size of your pointers and/or machine words
certainly does not make typical code (passing around 32-bit integers - or
smaller - most of the time) faster. Architectural improvements make code
faster, and the arch used in the A7 is much improved.

EDIT: Does the new iPhone even have 2GB of addressable memory? Does it benefit
from the 64-bit address space at all? Apple's specs don't say how much RAM the
thing has, and whether it has any VRAM. What else would the address space be
used for? I imagine you could map the whole internal flash to memory, but that
seems like an incredibly awful idea to me unless you want random addressing
errors to corrupt storage (maybe it'd be fine if only ring 0 had access)

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seanmcdirmid
It is obvious that smartphones will break the 4GB limit fairly soon (< 5
years), though I think right now the 5S has 1GB.

They added more registers and cleaned up some cruft in the 64-bit ISA, so that
is where the speed is coming from. You also get some speed from the extra bits
even if you aren't addressing 4+ GB of memory (e.g. 64 bit longs are native).

It doesn't make much sense to clean up the architecture without adding 64-bit
at the same time. X86 -> X64 followed the same path.

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threeseed
It would be much sooner than 5 years. And it's not about smartphones but
tablets.

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corresation
Absolutely horrendous post that uses the trope of presenting a wide array of
opinions as if they all come from a singular. ARMv8 is pretty cool, which is
why the entire industry is moving to it, and were before this.

