On Friday 08 April 2005 17:41, Sven Neumann wrote:
> Ketil Froyn <[EMAIL PROTECTED]> writes:
> > Thanks for the responses. I guess one major limiting factor could
> > be the types used internally by the GIMP. For instance, if it
> > does operations on uint32 type variables internally, I'd think
> > the compiler needs to be pretty clever to make use of 64 bit
> > operations. But now I'm getting into deep waters here here...:) I
> > was hoping someone in the know could confirm whether there's any
> > point going to 64 bit to make the GIMP faster, rather than just
> > getting a faster 32 bit CPU.
> The only real advantage you will get from a 64bit CPU is that you
> can address more than 4GB of RAM and will be able to handle very
> large images in GIMP provided that you actually stuff more than 4GB
> of RAM into your hardware.
Actually, these 64 bit CPUs have more registers as well. I'd expect
the compiler to make a better usage of them. Does this happen?
Ketil, as for the 64 bit integers - there could not possibly be a
program benefiting from this directly. They still do one operation a
time. Multiple operations with a single instruction (SIMD) is what
would speed up an app CPU usage are the correlate processing units
like 3Dnow, MMX and SSE. I'd guess the GIMP takes advantadge of MMX,
SSE, SSE2, and these had not improved on the new 64 bit chips (btw,
the registers relevant to SIMD were already 64 or 128 bit wide way
before the move to 64 bit on the general purpose registers).
Certainly the SSE2 code might get some improvements..there is room for
implementing 3Dnow code as well - it may not even get faster than
SSE2 code on Athlons, but it would quite a task for one to perform.
Do you have some spare time to learn coding 64/128 bit SIMD? :-)
> Gimp-user mailing list
Gimp-user mailing list