80 bit floating point emulator

[max haughton]

On Sunday, 6 February 2022 at 12:02:56 UTC, Ola Fosheim Grøstad 
wrote:
> On Sunday, 6 February 2022 at 11:27:28 UTC, max haughton wrote:
>> We already have moved on, technically. There are still some 
>> places using real in Phobos IIRC that should be violently 
>> culled because it destroys performance, but having the 
>> precision available isn't so bad.
>
> The only thing needed is to load and save 80bits from 64bit and 
> 128bit. I wonder who would want 80 bits? If they need more than 
> 64bits then they most likely want 128 bits or 256 bits.

80 bits actually exists in the hardware.

real isn't defined to be 80bits, it's just the widest float 
available in the hardware.

If we ever have a fp128 risc-v machine real could be 128bit there.