Fabrizio Diversi wrote:
>Ciao, >Everything started due to my curiosity to understand >why smsqe on latest HW platform (040 and 060) was so >slow in PAN and SCROLL operation (both for high and Ql >resolution). >1 - SMSQE with GD2 using standard QL resolution use >MOVEP instruction. There are no more than 20 MOVEP >references inside the sources that I replaced with >move and shift instructions. The result was more than >perfect obtaining , using speed test program >(test909), value aligned with the other type of test >(math) , graphics from 6.4 sec to .6 secs. > The answer - MOVEP is not implemented on the 68060, so it will be being emulated in software after an invalid instruction interrupt! No wonder it takes an age. A good point to look out for in any other code (I can't recall if Minerva uses movep). >2 - SMSQE do not use MOVEP in High resolution driver, >but the concept beyond should be the same . Maybe MULU >and DIVU are the responsible of this. >Conclusion : no conclusion !! >I personally do not have a deep M68000 assembler >capacity to try to remove efficiently suspicious >instruction , but I think a specific flag to identify >recent platform (060 and 040) should be introduced in >assembler compiler . I know this was already discussed >.... >Fabrizio > >
