New primitive types?
david at well-typed.com
Sun Aug 27 05:31:37 UTC 2017
Atomic operations, or the lack thereof, don't seem terribly relevant to immutable Haskell constructor fields.
David FeuerWell-Typed, LLP
-------- Original message --------From: Carter Schonwald <carter.schonwald at gmail.com> Date: 8/26/17 10:56 PM (GMT-05:00) To: Florian Weimer <fw at deneb.enyo.de>, Michal Terepeta <michal.terepeta at gmail.com> Cc: ghc-devs <ghc-devs at haskell.org> Subject: Re: New primitive types?
Which architectures are which?
I assume you mean the dec alpha allowed atomic operations on bytes... but
your phrasing is a teeny bit unclear
On Sat, Aug 19, 2017 at 4:34 AM Florian Weimer <fw at deneb.enyo.de> wrote:
> * Michal Terepeta:
> > On Tue, Aug 1, 2017 at 8:08 PM Carter Schonwald <
> carter.schonwald at gmail.com>
> > wrote:
> >> One issue with packed fields is that on many architectures you can't
> > quite do subword reads or
> >> writes. So it might not always be a win.
> > Could you give any examples?
> Historic DEC Alpha, now long obsolete.
> It is very hard to create compliant and performant implementations of
> Java 5, C 11 or C++ 11 on such architectures. All these languages
> (and their subsequent revisions) require that naturally aligned
> objects can be accessed independently. For example, you can't use a
> simple read-modify-write cycle to implement a single-byte store using
> word operations.
> That's why such architectures really do not have a future (or even a
> present), except maybe in niche markets such as GPGPU (but even there,
> things are heading towards the de-facto standard memory model).
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the ghc-devs