[X4U] Re: New Pentium Macs (Altivec)

[Eugene]

> On Thu, Jan 26, 2006 at 12:00:53PM CST, John Richardson <richards at spawar.navy.mil> wrote:
> : Kuestner, Bjoern wrote:
> : >
> : > Does anyone manufacture a SIMD computer?
> : 
> : Both SSE and Altivec units implement SIMD (or vector processing).
> 
> I do not consider a vector processor a SIMD computer. My definition is from
> the wiki paragraph on History.
> 
> "Later machines used a much larger number of relatively simple processors".
> 
> This allows the algorithm complexity to be knocked down by an order of
> magnitude on suitable algorithms from lets say O(n) to O(logn). Each
> processor needs a large amount of memory.
> 
> If you have a vector CPU with a large vector length as part of a system and
> large numbers of such CPU's and the communications architecture is designed
> to distribute data and distribute results to the other CPU's in the system
> then you have something resembling a SIMD machine (example: Virginia Tech
> Mac cluster). However, I do not consider the PowerPC vectors to be large
> enough.

John, your preference for the historical definition is nice.
But SIMD is the modern phrase for vector processing.  So that
means that everyone, including the wiki entry, considers SIMD
to include:

	"...the PowerPC's AltiVec, Intel's MMX, SSE, SSE2 and
	SSE3, AMD's 3DNow!, SPARCs VIS, PA-RISCs MAX and the
	MIPS MDMX and MIPS-3D...."

	<http://en.wikipedia.org/wiki/SIMD#Recent_SIMD_computers>


-- 
Eugene
http://www.coxar.pwp.blueyonder.co.uk/