Re: [hatari-devel] New SYNC release. New Hatari bugs found ;)

[ Thread Index | Date Index | More Archives ]

Le 04/11/2017 à 12:22, Nicolas Pomarède a écrit :

2) In TT mode (68030/16/MMU is what I tested) I had no issues until I added my intro, and then something really strange happened. It's been tested not to happen on real hw, but this issue is the same on Hatari v2.0 and current dev versions it seems. This is in the Audio Sculpture code, so something changes in the emulation from when I only loaded the AS binaries compared to when running the (TOS friendly) intro beforehand as well. But, on real hw it's fine.

Will look at this later.


I gave a look to this ; always complicated to debug, because caches are rather complex on the 68030. So far, I found nothing in the cpu code :(

But I see the intro does some uncompressing or copy some code to other part of the memory. Toni told me he had no idea of a bug in the curent i-cache code (which is certainly true, because all 68030 programs would likely crash rather often if i-cache was wrong).

So, it's quite likely that this uncompressing / copying of code is messing with the internal i-cache state and will make audio sculpture crashes later when accessing one of those addresses.

You can go the brute force way and disable the i-cache completely in the start of your intro (and in the start of AS). This should fix the problem.

A better solution if you want to keep i-cache enabled would be to flush it after each parts that writes code to memory (uncompressing and so on).
Hopefully, cleaning i-cache after such parts should fix the problem

(some packers/depackers automatically do that for you, but I don't know which one you used)


Mail converted by MHonArc 2.6.19+