Hi Johny,
> Hum. Do I remember wrong? I seem to remember that when you MOVB to a
> register, the value should be sign extended. So not just the low byte should
> have been modified.
I thought so too, but decided to check and found this is not true.
From the “VAX Architecture Handbook”, 1981, page 179:
“Unlike the PDP-11, but like the other VAX-11 instructions, MOVB and MOVW do
not modify the high order bytes of a register destination. Refer to the MOVZxL
and CVTxL instructions to update the full register contents.”
Regards,
Jeremy Begg
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