Fixed Point arithmetic support

Hello,

I see that GCC supports fixed point calculations

https://gcc.gnu.org/onlinedocs/gccint/Fixed-point-fractional-library-routines.html

I wonder what is the status of these routines and whether they could be integrated into the Arduino environment.

As of today, one may either use the C only fixed point implementation AvrFix
http://avrfix.sourceforge.net/
but the C only implementation is not quite efficient,

or one may use a set of pre-baked optimized assembly functions like
http://www.mikrocontroller.net/articles/AVR_Arithmetik
but they do not implement the fixed point arithmetic directly.

A direct GCC support of fixed point calculations would be perfect as I expect that these routines were finely hand optimized. Why are they not enabled in Arduino by default?

Thanks,
Vojtech