Re: Computer architects leaving Intel...

John Dallman <jgd@cix.co.uk> schrieb:

In article <vaqgtl$3526$1@dont-email.me>, cr88192@gmail.com (BGB) wrote:
>

On 8/29/2024 11:23 AM, MitchAlsup1 wrote:

>

With differing instructions, how does a software vendor write
software such that it can run near optimally on any implementation?

 
They presumably target whatever is common, or the least common
denominator (such as RV64G or RV64GC), and settle with "probably
good enough"...

>
ISVs can be proactive or passive about adopting a new ISA.

What is an ISV? I assume "SV" is for "software vendor", but what
does the I stand for?

[...]

Variant ISAs create fear, uncertainty and doubt, and that means delay.
ISA promotors fear delay, because their investors will run out of
patience.

Which makes me wonder why companies such as Intel introduce new
instructions all the time.  For people who compile their own code
(scientists and engineers) that can be OK, they can just use
-march=native (or equivalent), and it can even make sense to have
architecture-optimized core libraries such as BLAS, or switch on
availability of features such as AVX512 (but that again has many
sub-features and highly different performance characteristics,
depending on the micro-arch).

But standard software (office applications, browsers...) should
just run everywhere, and there it gets hard to justify.