DMD 1.034 and 2.018 releases

[Don]

Georg Lukas wrote:
> On Mon, 11 Aug 2008 09:55:26 -0400, Pete wrote:
>> Walter Bright Wrote:
>>> This one has (finally) got array operations implemented. For those who
>>> want to show off their leet assembler skills, the initial assembler
>>> implementation code is in phobos/internal/array*.d. Burton Radons wrote
>>> the assembler. Can you make it faster?
>> Not sure if someone else has already mentioned this but would it be
>> possible for the compiler to align these arrays on 16 byte boundaries in
>> order to maximise any possible vector efficiency. AFAIK you can't
>> actually specify align anything higher than align 8 at the moment which
>> is a bit of a problem.
> 
> From a short look at the array*.d source code, it would be better to 
> check if source and destination have the same alignment, i.e.:
> 
> a = 0xf00d0013 (3 mod 16)
> b = 0xdeaffff3 (3 mod 16)
> 
> In that case, the first 16-3 = 13 bytes can be handled using regular D 
> code, and the aligned SSE version can be used for the rest.
> 
> This would also work for slices, at least when both slices have the same 
> alignment remainder. I'm just not sure what overhead such a solution 
> would impose for small arrays.

Just begin with a check for minimal size. If less than that size, don't 
use SSE at all.

> 
> Georg