On 6 April 2016 at 07:41, Johan Engelen via Digitalmars-d
<digitalmars-d@puremagic.com> wrote:
> On Tuesday, 5 April 2016 at 21:29:41 UTC, Walter Bright wrote:
>>
>>
>> I want to make it clear that dmd does not generate AFX specific code, has
>> no switch to enable AFX code generation and has no basis for setting
>> predefined version identifiers for it.
>
>
> How about adding a "__target(...)" compile-time function, that would return
> false if the compiler doesn't know?
>
> __target("broadwell") --> true means: target cpu is broadwell, false means
> compiler doesn't know or target cpu is not broadwell.
>
> Would that work for all?
With respect to SIMD, knowing a processor model like 'broadwell' is
not helpful, since we really want to know 'sse4'. If we know processor
model, then we need to keep a compile-time table in our code somewhere
if every possible cpu ever known and it's associated feature set.
Knowing the feature we're interested is what we need.
