Load and store on the Alpha

[Thomas Koenig]

There's an interesting series of articles on the Alpha, written by a
Microsoft employee. The articles are partially interlinked.

The first part of the series (articles
1-7 are linked together) starts with
https://devblogs.microsoft.com/oldnewthing/20170808-00/?p=96775
and goes up to part 7 on how to load unaligned data.

The second part of the series (as far as they are linked) starts
with article 8 on how to store unaligned data, it can be found
at https://devblogs.microsoft.com/oldnewthing/20170816-00/?p=96825

Having read that, I think it is clear to see why the Byte/Word
extensions were added.

[Terje Mathisen]

It's been a few decades since I read the original alpha architecture
manual, afair you needed 7(or 8?) instructions to load a potentially
misaligned 16-bit value and 11 to write it?

Terje

--
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

[MitchAlsup]

On Thursday, June 30, 2022 at 2:19:18 PM UTC-5, Terje Mathisen wrote:
> Thomas Koenig wrote:
> > There's an interesting series of articles on the Alpha, written by a
> > Microsoft employee. The articles are partially interlinked.
> >
> > The first part of the series (articles
> > 1-7 are linked together) starts with
> > https://devblogs.microsoft.com/oldnewthing/20170808-00/?p=96775
> > and goes up to part 7 on how to load unaligned data.
> >
> > The second part of the series (as far as they are linked) starts
> > with article 8 on how to store unaligned data, it can be found
> > at https://devblogs.microsoft.com/oldnewthing/20170816-00/?p=96825
> >
> > Having read that, I think it is clear to see why the Byte/Word
> > extensions were added.
<
> It's been a few decades since I read the original alpha architecture
> manual, afair you needed 7(or 8?) instructions to load a potentially
> misaligned 16-bit value and 11 to write it?
<

First order, this seems both:
a) correct
b) bad.