|
From: | Philippe Michel |
Subject: | Re: [Bug-gnubg] Possible error in SSE sigmoid calculation |
Date: | Sat, 31 Dec 2011 15:26:39 +0100 (CET) |
User-agent: | Alpine 2.00 (BSF 1167 2008-08-23) |
I didn't run serious speed or non-regression tests, but it looks like this option is well worth using.
The differences between nosse and ssecvtt are due, I think, to the usage of a reciprocal instead of a true division in 1/(1+exp(x)). I suppose this was found acceptable at the time and would dissappear if everything was compiled with the -ffast-math flag. Maybe one could use something like#ifdef __FAST_MATH__ ... use reciprocal intrinsic #else ... use divide intrinsic #endif
[Prev in Thread] | Current Thread | [Next in Thread] |