Hi Bernd,
On 22/01/16 14:53, Bernd Schmidt wrote:
On 01/22/2016 10:52 AM, Kyrill Tkachov wrote:
AFAICT the new sequence is better than the old one even for
-mtune=cortex-a9 since it contains two fewer instructions.
Just curious (I think this patch series is good but will leave it to the arm
folks) - are these instructions equally expensive? Some CPUs are faster when
doing widening multiplies on smaller objects.
The widening multiplies are indeed faster on some targets (which is why we want
to keep them in the wmul-[12].c tests).
But for wmul-3.c the new sequence uses fewer instructions. So, while the
resulting sequences should be
of similar performance overall, the new sequence has a smaller code size.
Kyrill
Bernd
