On Saturday, 6 August 2016 at 09:35:32 UTC, Walter Bright wrote:
On 8/6/2016 1:21 AM, Ilya Yaroshenko wrote:
We need 2 new pragmas with the same syntax as `pragma(inline,
xxx)`:
1. `pragma(fusedMath)` allows fused mul-add, mul-sub, div-add,
div-sub operations.
2. `pragma(fastMath)` equivalents to [1]. This pragma can be
used to allow
extended precision.
The LDC fastmath bothers me a lot. It throws away proper NaN
and infinity handling, and throws away precision by allowing
reciprocal and algebraic transformations. As I've said before,
correctness should be first, not speed, and fastmath has
nothing to do with this thread.
I don't know what the point of fusedMath is.
It's not as cut and dry. Sometime, processing faster mean you can
process more data to begin with, and get a better result.
