On 1/22/19 12:31 PM, Rafael Tsuha wrote: > This patch simplifies the expression sinh (x) / cosh (x) to tanh (x). > This rule is mathematically valid. > > There's a slight difference in the result when applying this > optimization with x in the interval 0 < x <= 1e-4951. With the > optimization, the result using long double is -0 and without the > optimization, the result is +0. That's an indication something has gone wrong.
If I'm reading this correctly it sounds like tanh in that range is returning -0? If so, that just seems like the wrong output from tanh since IIUC for a positive input tanh will always have a positive output. Jeff
