This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
RE: builtin gamma function
I guess "fold" means do the computation at compile time?
No, it is being called with a variable. That is interesting that libc has a
gamma function. I will have to track down the implementation ...
-----Original Message-----
From: Ian Lance Taylor [mailto:iant@google.com]
Sent: Tuesday, November 15, 2011 1:58 AM
To: James Hirschorn
Cc: gcc@gcc.gnu.org; james.hirschorn@gmail.com
Subject: Re: builtin gamma function
James Hirschorn <James.Hirschorn@hotmail.com> writes:
> I have noticed that the builtin gamma function is very accurate and
> extremely fast. Can someone tell me where to find the source code for the
> implementation?
Are you calling it on a constant? Because gcc will fold gamma applied
to a constant which meets certain characteristics.
If you aren't calling it on a constant, then you are getting the
function from your libc. gcc does not itself include an implementation
of the gamma function.
Ian