Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

The author says who needs SIMD registers! And indeed on early processors like the 68000 you didn't have dedicated SIMD registers so in order to do SIMD within a register (SWAR) you had to do some variant on the techniques presented.

This was used in a fast 4 sample player where it could do math on four 8 bit wave table indices all in one 32 bit operation on the 68000. I had forgotten the details so this was a nice reminder of how it must have worked. I would otherwise have to disassemble it since source no longer exists. Speed was necessary since it was for the Atari ST and the work was done in an interrupt which was quite frequent and it was important to keep the overhead as minimal as possibe.



what does the disassembly look like


To find that out one would need to get the executable for The Duel : Test Drive II for the Atari ST and then disassemble the title screen.

But in any case you can compare the Chip Tune version of the title in Test Drive I vs the MOD player style tune in II

I https://www.youtube.com/watch?v=RGOdHT29Jpc

II https://www.youtube.com/watch?v=1GrdvcghDXE




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: