| Re: [hatari-devel] Suspected Hatari 2.3.0 regression (prefetch?) |
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- To: hatari-devel@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [hatari-devel] Suspected Hatari 2.3.0 regression (prefetch?)
- From: Christian Zietz <czietz@xxxxxxx>
- Date: Wed, 16 Dec 2020 13:41:05 +0100
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Roger Burrows schrieb:
movem.l (a0)+,d1-d7/a2-a6 ; copy 48 bytes ***
movem.l d1-d7/a2-a6,$1d0(a1)
The crash occurs in the second (and last) time through the loop, at the
instruction marked with *** above. After that instruction, a0 will point to
$ff9c00 (although that address has not been read, at least from a programming
POV). The error msg from Hatari is "Bus Error reading at address $ffff9c00".
I know that the 68000 in fact does an extra memory access for MOVEM.x
(Ax)+,... that can cause an unexpected bus error. I'm unsure, however,
if newer 68k CPUs exhibit this side effect, too. To me, the fact that
DELMPAINT runs on a real Falcon without crashing indicates that this
extra access does not happen on a real 68030.
Regards
Christian
--
Christian Zietz - CHZ-Soft - czietz@xxxxxxx
WWW: https://www.chzsoft.de/
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