Macro invocation, Local macro labels, Optional macro arguments – Zilog ZUSBOPTS User Manual
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Macros
Zilog Developer Studio II – ZNEO™
User Manual
249
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Macro Invocation
A macro is invoked by specifying the macro name and following the name with the
desired arguments. Use commas to separate the arguments.
Syntax
<macroname>[<arg>[(,<arg>)]...]
Example
store R1,R2,R3
This macro invocation causes registers R1 and R2 to be added and the result stored in reg-
ister R3.
Local Macro Labels
Local macro labels allow labels to be used within multiple macro expansions without
duplication. When used within the body of a macro, symbols preceded by two dollar signs
(
$$
) are considered local to the scope of the macro and therefore are guaranteed to be
unique. The two dollars signs are replaced by an underscore followed by a macro invoca-
tion number.
Syntax
$$
<label>
Example
LJMP: MACRO cc,label
JP cc,$$lab
JP label
$$lab:
ENDMAC
Optional Macro Arguments
A macro can be defined to handle omitted arguments using the
IFMA
(if macro argument)
conditional directive within the macro. The conditional directive can be used to detect if
an argument was supplied with the invocation.
Example
MISSING_ARG: MACRO ARG0,ARG1,ARG2
IFMA 2