Thank you for your replies.
I too was originally taught to use DS 0H for a label statement, because it
guaranteed halfword instruction alignment. But I recently started using EQU *
because a) it seemed to be clearer as to the intent, and b) I figured that if
your instructions weren't aligned you've got bigger problems. I hadn't
considered someone intentionally embedding an odd size storage area in the
instruction stream without taking care to realign. I may rethink this, perhaps
with Charles Mills suggestion to use DS 0H at the start of routines but
continue to use EQU * inside them.
As for the question of stand-alone labels vs. putting the label on the next
instruction, I like the stand-alone labels because it promotes maintainable
code. You can put comments on the label, but more important is that you can
code multiple labels for the same address.
For example, if you have this kind of structure (begging Outlook not to
collapse the leading spaces):
if x
if y
do a
endif
else
do b
endif
you can code one label for the first ENDIF and another for the ELSE. Then
later if you want to insert more instructions immediately before the ELSE, it
is very clear where to put them and none of the labels change.
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