Everyone came up with the right alternatives.

Among XR, SLR, and SR,
XR is thought best (not necessarily measurable better).

If you don't need a condition code (and certainly if you need to preserve a 
condition code), LHI is thought best.

I'm not sure to what extent the fact that the first three are 2-byte 
instructions and LHI is a 4-byte instruction comes into play. It is apparent 
that LHI creates a bigger instruction-space footprint. That in turn can lead to 
increased cache line usage.

Peter Relson
z/OS Core Technology Design

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