newCTFE is getting ported to 2.092

[Stefan Koch]

On Friday, 5 June 2020 at 21:52:05 UTC, Steven Schveighoffer 
wrote:
> On 6/5/20 5:46 PM, Stefan Koch wrote:
>> On Friday, 5 June 2020 at 21:09:37 UTC, H. S. Teoh wrote:
>>> On Fri, Jun 05, 2020 at 08:24:10PM +0000, Stefan Koch via 
>>> Digitalmars-d wrote:
>>>> newCTFE port to 2.092
>>>
>>> How close are we to newCTFE being mergeable?  Been slobbering 
>>> over it since it was first announced way back when, can't 
>>> wait for it to arrive already!
>>>
>> Trust me once it's merged you'll be disappointed because the 
>> problem were templates all along (hence my work on type 
>> functions)
>
> But without newCTFE the cure is worse than the disease.
>
> I think it's going to allow more possibilities of replacing 
> templates with CTFE handling.
>
> I have some ideas to do type functions without specialized 
> compiler support. But I think it would be painful without a 
> better CTFE engine.
>
> -Steve

I have a meaningless performance number for you.

for this code:
uint f(uint x)
{
     uint acc;
     foreach(i; 0 .. x) acc += x;
     return acc;
}

pragma(msg, f(ushort.max * 2));

oldCtfeTime: 150 milliseconds.
newCtfeTime:  12 milliseconds.

around a 12x speedup for simple stuff like this.
For more complicated cases the numbers are going to be more 
varied.