[Info-vax] Itanium support is back in GCC 15

[John Dallman]

In article <lp6284Fll3cU1 at mid.individual.net>,
gerard.calliet at pia-sofer.fr (gcalliet) wrote:

> About Itanium, who knows? I heard about some specific uses of 
> Itanium. So perhaps a very little business with Itanium could exist 
> sometime.

It can't last now. There are a finite supply of Itanium CPUs and no more
being made. 

> On my side I have always thought the failure of Itanium - they said 
> Itanic - have been just the bad meeting between the conservatism of 
> geeks and the inchoate laws of the market.

It also had fundamental technical flaws. The basic idea of EPIC, that a
compiler with plenty of time to plan, can optimise memory advance loads
to make Out-of-Order execution unnecessary, is wrong.

It would be possible to do that in a single-core system with no processor
caches, a single-tasking operating system, and few interrupts going off.
In a multi-processor, multi-tasking system which is taking interrupts, it
is impossible to know in advance what data will be in which cache levels,
and hence to optimise memory access in advance. 

John