On Thu, 15 Nov 2018 08:33:55 -0800, Charles Mills wrote:

>LARL is also very cool. It is like LA without a base register.

Agreed. One thing to be aware of with LARL. It uses a signed 
halfword that is added to the current PSW address. As a result 
it cannot be used to get the address of an odd address. Nor 
can it be used to get an address in a DSECT, or in a CSECT that 
is not part of the same load module.

There are still situations where LA is appropriate.

There is no need to change every Branch instruction to Branch 
Relative (Jump) in order to start using relative instructions. If you 
are changing an existing program you can code any new branches 
as branch relative, except for the situation where you want to use 
an indexed branch.

-- 
Tom Marchant

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