Now that Andreas is on board, time to dust off some older issues
of mine. :-)
I verified that current GCC HEAD generates fsincos on FreeBSD/i386
with -ffastmath (and no options otherwise), and generates a call
to a sin() function otherwise.
So, okay to apply this patch? And if so, okay to push back to
GCC 5 and 4.9 as well?
Gerald
On Wed, 16 Feb 2011, Gerald Pfeifer wrote:
> The documentation indicates that -mno-fancy-math-387 is the default
> on FreeBSD, yet I do not see any code actually implementing that, and
> I verified that the following
>
> #include <math.h>
>
> double f(double d) {
> return __builtin_sin(d);
> }
>
> did generate fsin with -ffast-math as the only option.
>
> Richard, http://gcc.gnu.org/ml/gcc-patches/2002-03/msg02001.html was
> the last time someone really made changes in this area, though the
> reference to FreeBSD predates your patch where you added OpenBSD and
> NetBSD for both of which I _do_ see code in config/i386 to that extent,
> unlike FreeBSD.
>
> Am I missing something obvious, or is the patch below okay?
>
> Gerald
>
>
> 2011-02-16 Gerald Pfeifer <ger...@pfeifer.com>
>
> PR target/37072
> * doc/invoke.texi (i386 and x86-64 Options): -mno-fancy-math-387
> is not actually the default on FreeBSD.
> Uppercase CPU.
>
> Index: doc/invoke.texi
> ===================================================================
> --- doc/invoke.texi (revision 170120)
> +++ doc/invoke.texi (working copy)
> @@ -12273,9 +12273,9 @@
> @opindex mno-fancy-math-387
> Some 387 emulators do not support the @code{sin}, @code{cos} and
> @code{sqrt} instructions for the 387. Specify this option to avoid
> -generating those instructions. This option is the default on FreeBSD,
> +generating those instructions. This option is the default on
> OpenBSD and NetBSD@. This option is overridden when @option{-march}
> -indicates that the target cpu will always have an FPU and so the
> +indicates that the target CPU will always have an FPU and so the
> instruction will not need emulation. As of revision 2.6.1, these
> instructions are not generated unless you also use the
> @option{-funsafe-math-optimizations} switch.
>
