CTFE pow()

[Manu via Digitalmars-d]

Awesome. Really looking forward to this! :)

On 13 January 2015 at 03:12, Iain Buclaw via Digitalmars-d
<digitalmars-d at puremagic.com> wrote:
> On 2 January 2015 at 14:19, Iain Buclaw <ibuclaw at gdcproject.org> wrote:
>> On 1 January 2015 at 18:40, H. S. Teoh via Digitalmars-d
>> <digitalmars-d at puremagic.com> wrote:
>>> On Fri, Jan 02, 2015 at 02:56:16AM +1000, Manu via Digitalmars-d wrote:
>>>> Does anyone know how to fix this? Can we please do so? It's been a
>>>> problem for like 5 years it seems.
>>>> It's a bit insane that we can't resolve any non-linear functions at
>>>> compile time.
>>>
>>> I've been waiting for this since like, forever. We even have a D code
>>> implementation of pow() already (thanks to Iain), which *should* have
>>> been CTFE-able, if it weren't for CTFE limitations that prohibit
>>> reinterpreting float values in binary, which is required for certain
>>> basic operations like isInfinite, isNaN, etc..
>>>
>>> So it seems that the blocker right now is CTFE, which, unfortunately, is
>>> not a pretty piece of code, and requires quite a bit of care to get it
>>> done right.
>>>
>>
>> The fundamental structure is in place in Target. where the paintAsType
>> implementation encodes/decodes from a char buffer (and supports up to
>> 512 bytes).  You can add support for painting a double as a ushort[4]
>> by adding a loop, decodeInteger(e, buffer), decodeInteger(e,
>> buffer+2), etc...
>>
>> The second part (and more crucial) is adding the capability into CTFE.
>> Shouldn't be much work, but I've yet to get round to it.
>>
>> See: https://github.com/D-Programming-Language/dmd/blob/master/src/target.c#L287
>>
>>
>
> I've started a branch which works on this.  I expect it will take me a
> week to finish with unittests.
>
> Iain.