Re: is Vax addressing sane today

On Tue, 1 Oct 2024 10:12 +0100 (BST)
jgd@cix.co.uk (John Dallman) wrote:

In article <vdg3d1$2kdqr$1@dont-email.me>, ldo@nz.invalid (Lawrence
D'Oliveiro) wrote:
 

Wasn't Windows NT supposed to be some kind of _portable_ OS? Wasn't
it supposed to run on big-endian architectures too, like POWER, MIPS
and SPARC? 

 
It did. I have no experience with Windows NT on SPARC or PowerPC,

Did WinNT on SPARC ever ship? I don't think so.

but
the OS ran fine on MIPS. It was a commercial failure, because MIPS
didn't keep up with the performance growth of x86.
 

Wasn't MIPS edition of WinNT Little Endian?

PowerPC did for a while, but the company interested in NT on PowerPC
was IBM, and their hardware prices were a /lot/ higher than x86
prices. They didn't see that as a problem, but all the potential
customers did.
 
John

Now I wonder what endiannes was used by PowerPC variant WinNT.
In theory, PPC/POWER could run in Little Endian mode, but before v3 of
POWER ISA it wasn't as full-featured as Big Endian mode. If I am not
mistaken, the difference was that in LE mode there was no support for
unaligned memory accesses.