https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78379
--- Comment #16 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
(In reply to Thomas Koenig from comment #15)
> OMG, the world of processors is more complicated than I thought.
> So, these rather modern AMD chips support AVX, but suck at it.
>
> Two questions:
>
> - Can you check if -mfma3 and/or -mfma4 make any difference?
>
> - If you start any program compiled with -g under the debugger, break
> anywhere (for example at the beginning of the main program)
> and do a "p __cpu_model", what do you get?
The A10-5800K
p __cpu_model
$1 = {__cpu_vendor = 2, __cpu_type = 5, __cpu_subtype = 8,
__cpu_features = {883711}}
The A8:
p __cpu_model
$2 = {__cpu_vendor = 2, __cpu_type = 9, __cpu_subtype = 0,
__cpu_features = {855039}}
The A6:
p __cpu_model
$1 = {__cpu_vendor = 2, __cpu_type = 0, __cpu_subtype = 0,
__cpu_features = {2111}}
neither -mfma nor -mfma4 help
