On 15/01/12 3:31 AM, Andrei Alexandrescu wrote:
1. SIMD is not the top of the list. Two weeks ago it wasn't _on_ the list. Now it's like the last 'copter outta Saigon.
That's not true. SIMD intrinsics has always been on the list. I've only been in this newsgroup for a year or so, but I've definitely seen D's lack of SIMD support mentioned in several discussions so far. It's a frequent complaint about the language.
2. We haven't identified game designers as a core market, and one that's more important than e.g. general purpose programmers who need the like of working qualifiers, multithreading, and shared libraries.
Game programming is quite clearly a very large market for D. The game industry is perhaps one of the largest software industries that still relies on having C/C++ level of efficiency and low-level access. It's also an industry that is absolutely sick of having to use C++. D is quite close to the perfect language for game developers.
I think it's also telling that perhaps the most prolific (ex-)D coder, Tomasz, was a game programmer, and that one of the largest D libraries is Derelict, which is also aimed at games.
Finally, if you look at the dsource projects, http://dsource.org/projects/ you'll see that Games make up quite a large chunk of what people are using D for.
What do you think our core market is?
3. There was never a promise or even a mention that we'll deliver SIMD. We virtually promise we deliver threads and expressive qualifiers, and there's still work to do on that.
Fair point.
4. There was broad agreement that the main foci going forward would be quality, expressive qualifiers, shared libraries, Phobos work, and publicizing the language. We can't work with and publicize D's awesome concurrency design if parts of it aren't implemented.
I suspect that SIMD support will greatly help to publicize the language.
5. The SIMD work has _zero_ acceleration on existing code; it only allows experts to write non-portable code that uses SIMD instructions. Updating to the next release of dmd has zero SIMD-related benefit to statistically our entire user base.
Where are you getting the figures for the % of people that will benefit from SIMD support? The SIMD support thread is rather large, so that suggests to me that a significant number of people are quite interested in the SIMD work.
Walter and I spend hours on the phone discussing strategies and tactics to make D more successful. And then comes this binge. Doing anything on SIMD now is a mistake that I am sorry I was unable to stop. About the only thing that's good about it all is that it'll be over soon.
I can't speak on your private conversations with Walter, but I think you're underestimating how important SIMD support is for D.
Also, it appears (from his rate of progress) that Walter is quite enjoying the SIMD work. I see no harm in a short-lived "binge" if it reinvigorates Walter's interest in compiler work -- especially if you please a large part of the community in the process.
