[Simh] PDP-11 MUL / DIV Bug

[Ludwig TAUER]

Hi folks!

Seems I have found a bug in the PDP-11 emulating the
MUL instruction.

The current code takes the specified register as source
instead of the register pair R and R+1 if the register is even.

The DIV instruction is also invalid, but the other way around:
if R is odd, R is duplicated into the high half of the 32 bit int.

The attached patch will correct the problems.

Hope that helps

Ludwig Tauer
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