Enlighten me.
What is the purpose of AR mode?
Does not a length of zero mean that the content of the corresponding
address register not be used?
On 2025-03-18 05:32, Richard Zierdt wrote:
The following is documented in PoPs, but what the hey.
Primary (ASC) Mode: MVCL R0,Rx is fine
AR (ASC) Mode: MVCL R0,Rx is *not* fine — AR0 is not honored
The PoPs manual on MVCL:
"In the access-register mode, the contents of access
register R1 and access register R2 are compared. If
the R1 or R2 field is zero, 32 zeros are used rather
than the contents of access register 0. "
There is probably a reason why AR0 is not supported as MVCL operands;
it's just that it's inconsistent with the corresponding behavior in
Primary ACS mode.
Richard Zierdt
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