D for scientific computing

[H. S. Teoh]

On Thu, Jan 24, 2013 at 05:28:16PM +0100, Joseph Rushton Wakeling wrote:
> On 01/24/2013 02:11 PM, John Colvin wrote:
> >Walter, I know you like working with the current backend and you
> >understand it etc..., but this gives dmd a bus factor of 1 and is
> >slowing down code in the process.
> 
> Honestly, I don't feel this is too strong an issue.  The point of
> dmd is to be a reference compiler -- speed is nice if it's possible,
> but not the most important consideration.

I think it would be ideal if the dmd front end were more isolated from
the back end, so that it's easier to port to gdc/ldc (i.e. it can happen
in the matter of days after a dmd release, not, say, weeks or months).

But I believe Walter has already said that patches to this effect are
welcome, so I can only see the situation improve in the future.

Nevertheless, I also have made the same observation that code produced
by gdc consistently outperforms code produced by dmd. Usually by about
20-30%, sometimes as much as 50-60%, IME. That's a pretty big
discrepancy for me, esp. when I'm doing compute-intensive geometric
computations.


> The most important thing is that new frontend updates can get merged
> quickly into ldc/gdc, so that there is no time lag between new
> feature development and their incorporation into other compilers.

Agreed.


T

-- 
It is of the new things that men tire --- of fashions and proposals and improvements and change. It is the old things that startle and intoxicate. It is the old things that are young. -- G.K. Chesterton