|Re: [hatari-devel] 68030 cycle timings for 64bit div/mul|
[ Thread Index |
| More lists.tuxfamily.org/hatari-devel Archives
Le 29/01/2013 16:49, Douglas Little a écrit :
This is a question for Laurent I think...
Where can I find the instruction times for the 'div' and 'mul' 64bit
(long form) instructions in the Hatari timing table "falcon_cycle030.h"?
I see indirection to certain tables "table_falcon_cycles_DIVS_L" but the
addressing mode for Dr:Dq does not seem to be present in the comments.
Is it handled specially somewhere else?
it's not handled. 64 bit mul/div are more complex than the 68000
equivalent and so far no one has reverse engineered those instructions
to "guess" the algorithm and its timing.