Re: [hatari-devel] Re: 040/060 emulation issue with Q2

[Douglas Little <doug694@xxxxxxxxxxxxxx>]

OK, so back to the opcode ff70, and looking at 68030 user manual chapter 10..1.3 with the format of line F instructions, it is stated that CpID 001 (bit 9 to 11) is used for 68881 and 6882, and 111 is reserved.

So, this really looks like an illegal instruction that should not be used in the 1st place. Is this handmade asm, or the result of a C compiler ?

This case was the result of the C compiler. However, I also noted that the PC addresses were incrementing by strange values in the debugger trace - too big for normal instructions ($00028092 -> $000280ce). So it may well have just run off into dead space by that point. The whole thing looks quite strange TBH.

I'll try to get something a bit more concrete later on after work.

D