GDC review process.

[Alex Rønne Petersen]

On 19-06-2012 23:22, Manu wrote:
> On 19 June 2012 23:59, deadalnix <deadalnix at gmail.com
> <mailto:deadalnix at gmail.com>> wrote:
>
>     Le 19/06/2012 22:08, Iain Buclaw a écrit :
>
>           From what I gathered from further discussion, it made sense for
>         embedded platforms, such as ARM, but not x86.
>
>
>     It has proven to be useful to me, not only for performances reasons,
>     but also for low level manipulations.
>
>     It don't see what make ARM that different on regard to inline
>     assembly capabilities.
>
>
> If you had the register alias feature I described above, would you be
> ale to write such low-level manipulations using intrinsics?
> I think I would be able to rewrite all x86 asm blocks I've ever written
> using that feature.
>
> ARM and PPC both have unique features relating to their branch control
> and branch prediction that x86 doesn't have. Sadly, all high level
> languages COMPLETELY overlook such features when designing high level
> expressions, because they are traditionally designed for x86 first.

To be fair, ARM v8/AArch64 has eliminated predicated execution, simply 
because it turned out that the complexity of writing languages and 
compilers for it was not worth it, compared to just having good branch 
prediction.

> A thorough set of intrinsics can allow access to these features though,
> although since they're related to branch control/conditional execution,
> it feels clumsy, since you lose the feeling of structured code; ie, no
> scoped if blocks, loop constructs, etc,  if you have to use intrinsics
> to generate conditions or masks.
>
> ARM is the most common architecture on earth now. It would be nice if D
> were able to take better advantage of the architecture.


-- 
Alex Rønne Petersen
alex at lycus.org
http://lycus.org