| Re: [hatari-devel] Reeking rumber analysis |
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Am Sun, 08 Sep 2013 23:33:01 +0200
schrieb Laurent Sallafranque <laurent.sallafranque@xxxxxxx>:
> Hi,
>
> I've given a closer look at reeking rumber :
[...]
> $0707a0 : 2811 move.l (a1),d4
> $0707a2 : 2612 move.l (a2),d3
> $0707a4 : b803 cmp.b d3,d4
> >
> $0707a6 : 6706 beq.s $707ae
> $0707a8 : 6202 bhi.s $707ac
> $0707aa : 5103 subq.b #8,d3
> $0707ac : 5803 addq.b #4,d3
> $0707ae : e19b rol.l #8,d3
> $0707b0 : e19c rol.l #8,d4
> $0707b2 : b803 cmp.b d3,d4
> $0707b4 : 6706 beq.s $707bc
> >
> $0707b6 : 6202 bhi.s $707ba
> $0707b8 : 5103 subq.b #8,d3
> $0707ba : 5803 addq.b #4,d3
> $0707bc : e19b rol.l #8,d3
> $0707be : e19c rol.l #8,d4
> $0707c0 : b803 cmp.b d3,d4
> $0707c2 : 6706 beq.s $707ca
> $0707c4 : 6202 bhi.s $707c8
> >
> $0707c6 : 5103 subq.b #8,d3
> $0707c8 : 5803 addq.b #4,d3
> $0707ca : 4843 swap d3
> $0707cc : b699 cmp.l (a1)+,d3
> $0707ce : 6702 beq.s $707d2
> $0707d0 : 7a01 moveq #1,d5
> $0707d2 : 24c3 move.l d3,(a2)+
> $0707d4 : 51ce ffca dbra d6,$707a0
> >
> $0707d8 : 4a85 tst.l d5
> <------- Here is the the test that never goes throw with hatari
> $0707da : 6680 bne.s $7075c
> $0707dc : 4cdf 07ff movem.l (sp)+,d0-d7/a0-a2
> $0707e0 : 4e75 rts
>
>
> At least, the game runs under hatari except for this infinite loop that
> never finishs because of this d5 register.
>
> May this gives some ideas to somebody.
As far as I can see, d5 is never set back to 0 in this loop ... that
could mean that it is supposed to be changed by an interrupt handler
instead. Have you checked the usual suspects? VBL? HBL? Timer-B?
Thomas