Does dmd have SSE intrinsics?

[grauzone]

Robert Jacques wrote:
> On Tue, 22 Sep 2009 12:32:25 -0400, Andrei Alexandrescu 
> <SeeWebsiteForEmail at erdani.org> wrote:
>> Daniel Keep wrote:
> [snip]
>>>  The problem is that currently you have a class of types which can be
>>> passed as arguments but cannot be returned.
>>>  For example, Tango's Variant has this horrible hack where the ACTUAL
>>> definition of Variant.get is:
>>>      returnT!(S) get(S)();
>>>  where you have:
>>>      template returnT(T)
>>>     {
>>>         static if( isStaticArrayType!(T) )
>>>             alias typeof(T.dup) returnT;
>>>         else
>>>             alias T returnT;
>>>     }
>>>  I can't recall the number of times this stupid hole in the language has
>>> bitten me.  As for safety concerns, it's really no different to allowing
>>> people to return delegates.  Not a very good reason, but I *REALLY* hate
>>> having to special-case static arrays.
>>
>> Yah, same in std.variant. I think there it's called 
>> DecayStaticToDynamicArray!T. Has someone added the correct handling of 
>> static arrays to bugzilla? Walter wants to implement it, but we want 
>> to make sure it's not forgotten.
> 
> Well, what is the correct handling? Struct style RVO or delegate 
> auto-magical heap allocation? Something else?
> 
> Both solutions are far from perfect.
> RVO breaks the reference semantics of arrays, though it works for many 
> common cases and is high performance. This would be my choice, as I 
> would like to efficiently return short vectors from functions.
> Delegate style heap allocation runs into the whole 
> I'd-rather-be-safe-than-sorry issue of excessive heap allocations. I'd 
> imagine this would be better for generic code, since it would always work.

I think static arrays should be value types. Then this isn't a problem 
anymore, and returning a static array can be handled exactly like 
returning structs.

Didn't Walter once say that a type shouldn't behave differently, if it's 
wrapped into a struct? With current static array semantics, this rule is 
violated. If a static array has reference or value semantics kind of 
depends, if it's inside a struct: if you copy a struct, the embedded 
static array obviously looses its reference semantics.

Also, I second that it should be possible to declare void variables. 
It'd be really useful for doing return value handling when transparently 
wrapping delegate calls in generic code.