[hatari-devel] [Bug found] : divul.l

[Laurent Sallafranque <laurent.sallafranque@xxxxxxx>]

Hi all,

I think I've found another bug in hatari (new core, but probably old 
core too).

In my test, I've coded the following :

move.l        #100,d3
divul.l    #100000,d3:d4


Hatari disassembled code shows :

$05bf88 : 263c 0000 0064                       move.l    #$64,d3
$05bf8e : 4c7c 4003 0001 86a0                  divu.l    #$186a0,d4


Hatari Trace mode :

> c 2
cpu video_cyc= 27076 452@ 52 : 0005BF88 263c 0000 0064 MOVE.L #$00000064,D3
cpu video_cyc= 27082 458@ 52 : 0005BF8E 4c7c 4003 0001 86a0 DIVL.L 
#$4003,#$000186a0



Hatari registers before the instruction :

CPU=$5bf88, VBL=49175, FrameCycles=37816, HBL=153, LineCycles=74, DSP=$51
> r
  D0 00000000   D1 00000000   D2 00000000   D3 00000000
  D4 00000000   D5 00000000   D6 00000000   D7 00000000
  A0 00000000   A1 00000000   A2 00000000   A3 00000000
  A4 0005BF96   A5 0005BF96   A6 00DC16C6   A7 00DC16F8
USP  00DC16F8 ISP  00008870 SFC  00000000 DFC  00000000
CACR 00000000 VBR  00000000 CAAR 00000000 MSP  00000000
T=00 S=0 M=0 X=0 N=0 Z=0 V=0 C=0 IMASK=3 STP=0
FP0: 0 FP1: 0 FP2: 0 FP3: 0
FP4: 0 FP5: 0 FP6: 0 FP7: 0
N=0 Z=0 I=0 NAN=0
0005BF88 263c 0000 0064           MOVE.L #$00000064,D3
Next PC: 0005bf8e
> trace cpu_disasm
> c 3
Returning to emulation for 3 CPU instructions...
cpu video_cyc= 37816  74@153 : 0005BF88 263c 0000 0064 MOVE.L #$00000064,D3
cpu video_cyc= 37822  80@153 : 0005BF8E 4c7c 4003 0001 86a0 DIVL.L 
#$4003,#$000186a0

CPU=$5bf96, VBL=49175, FrameCycles=37868, HBL=153, LineCycles=126, DSP=$51
> r
  D0 00000000   D1 00000000   D2 00000000   D3 00000000
  D4 00000000   D5 00000000   D6 00000000   D7 00000000
  A0 00000000   A1 00000000   A2 00000000   A3 00000000
  A4 0005BF96   A5 0005BF96   A6 00DC16C6   A7 00DC16F8
USP  00DC16F8 ISP  00008870 SFC  00000000 DFC  00000000
CACR 00000000 VBR  00000000 CAAR 00000000 MSP  00000000
T=00 S=0 M=0 X=0 N=0 Z=1 V=0 C=0 IMASK=3 STP=0
FP0: 0 FP1: 0 FP2: 0 FP3: 0
FP4: 0 FP5: 0 FP6: 0 FP7: 0
N=0 Z=0 I=0 NAN=0
0005BF96 0000 0000                OR.B #$00,D0
Next PC: 0005bf9a


After execution, the registers values haven't changed at all.


TTDigger disassembler (under hatari) shows the correct code (I've 
dissassembled the .prg I just compiled before)


It seems to me that hatari doesn't emulate well the long word divisions 
instructions divu.l divul.l ... and divs.l divsl.l ...

Does someone confirm that ?

Regards

Laurent