"Scott Marlowe" <scott.marlowe@gmail.com> writes:
> On Nov 12, 2007 11:37 AM, Sam Mason <sam@samason.me.uk> wrote:
>> And what's the performance hit of using native 64bit code? I'd guess
>> similar, moving twice as much data around with each pointer has got to
>> affect things.
>
> That's not been my experience. It's not like everything you do
> requires 64 bits to be moved where in 32 bit code only 32 were moved.
> The performance gain of the 64 bit machine doing 64 bit operations
> over the 32 bit machine doing them (i.e. floating point etc...) is so
> much more that it more than makes up for the overhead of running in 64
> bit mode.
Plus, 64-bit mode gives you twice as many CPU registers, which is a
huge win for some algorithms, though in many cases it doesn't make
much of a difference.
-Doug
