[rescue] SS10 Accessories

[Romain Dolbeau]

2015-11-22 4:06 GMT+01:00 Eddie Cottongim <jcotton at intergate.net>:

> Out of curiosity, when Linux/Solaris etc dropped support for sun4m/sun4c,
> is it because there was something inconvenient about the architecture that
> they wanted to get rid of
>

Probably. SPARC V7 (all sun4, sun4c & the 600MP with SM100 modules) doesn't
have integer multiply/divide instructions, which were added in SPARC V8.
Supporting V7 means you can't use those in libraries & binary software, or
you need two versions which is cumbersome. For some software the more
efficient integer instructions are a boon (some cryptographic algorithms
come to mind).

Then V8 (all sun4m but the SM100 modules)  was 32 bits only and didn't have
more sophisticated instructions for synchronization (it's missing
compare-and-swap for instance). SPARC V9 has them in 64 bits and in the 32
bits "V8plus" mode, plus some additional stuff like better condition
registers.

By the time Solaris 10 came out, even x86 had moved to 64 bits (all the
surviving RISC architectures but ARM had moved to 64 bits in the 90s, or
started as 64 bits like Alpha). Supporting 32 bits didn't make much sense
in servers or even desktop (or deskside :-) then.

Cordially,

-- 
Romain Dolbeau