Floating point rounding modes: we should restrict them slightly

[Lionello Lunesu]

#ponce wrote:
> Why not imposing a rounding mode (ex :  toward minus infinity) ?
> And then disallowing to change it in assembly.
> 
> I mean, you can still do :
>   round(x) as floor(x + 0.5L)
>   ceil(x) as floor(x + 1.0L)
> 
> Iit would cost some precision with large floating-point number, but not much since rounding such large numbers has few meaning.
> 
> It would clear up the rounding-mode mess a bit.

Shouldn't ceil(1.0) return 1.0, and wouldn't floor(1.0 + 1.0L) return 2.0?

L.