https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109008
--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> --- I think for the reverse op I'd naiively try to compute the result as we do now and then extend the range by one ulp of the input range with the largest magnitude. Does real_nextafter (0.0) result in a denormal? For multiplication we have to consider underflow, say, if 0.0 = x * 1e-63; depending on whether we represent denormals in ranges x is the range where the operation underflows. As said we probably have to think and document what we do for individual operations. We can also conservatively widen the input ranges by one ulp, that's going to be always correct and maybe the best thing to do for GCC 13? It should be only necessary for the reverse operations.
