[ARMedslack] mfloat-abi

[Thorsten Mühlfelder]

Am Friday 04 February 2011 15:07:34 schrieb Stuart Winter:
> > Hmm, I did not really see what's the default here (soft, softfp, hard)?
>
> Me neither - I thought that the specs there were what was used by default.
> I had a further quick read about it and that isn't the case.
>
> > As soft/softfpe is some kind of porting floating point operations to
> > integer I've assumed that Armed Slack uses mfloat-abi=hard, which
> > forwards the floating point instructions to the slow kernel FP emulation.
>
> Yes, it's been ages since I looked at the issue -- I know the oldabi
> ARMedslack used that method, but I'd forgotten about the EABI version.
>
> The floating point used is the same as Debian use for their armel port:
> http://wiki.debian.org/ArmEabiPort

They say:
"Floating point performance, with or without an FPU is very much faster, and 
mixing soft and hardfloat code is possible".
This was not possible with OABI but I've never tested this on EABI. Building 
libvorbis with soft, softfp & hard may enlighten me ;-) If it is possible to 
build these three then mixing is allowed and a cpu usage comparison can 
follow.