Table of Contents - TG Drives

38
Multiline Macro
MACRO DEFINITION
PL2 NATIVE POSITION LANGUAGE
A macro definition needs information regarding the type of the argument, with an
arg-specifier placed after each argument.
Format:
.MACRO
.MACRO foo [,sym:arg-specifier] [,nn:as] [; Comment]
[lab:] [macro body]
.ENDMACRO [; Comment]
The macro body specifies what operation the “new instruction” will perform when
invoked (macro expansion). Standard native instructions or other macros can be
used and the nesting depth of a macro calling another macro is limited only by the
amount of available memory. Macro recursion is not allowed and generates an
error message.
Names of labels within the macro body can be used freely. Each macro maintains
its own symbol table. This means that symbols defined in the program scope are
not accessible within a macro definition.
Example:
.DEFINE foo = 4711 ; The symbol has program scope
.MACRO bar, foobar:v
LET r0, foo ; This will generate an error, foo is undefined
.ENDMACRO
In the list file, any label used within a macro definition ends with the ($) symbol
instead of the standard colon (:) symbol.
NOTE: It is possible to use the absolute label format in a macro definition, but there
can only be one within the macro. For a second occurrence within the macro, the
compiler generates a “previous line overwritten” error message.
MACRO ARG SPECIFIERS
Arg specifiers are divided into 8 categories
No Symbol Description NOTE
1 r General register type, Reg, XReg, or IRreg.
2 v General value type, i32 or i16.
3 lrf General line reference.
4 i32 Long value.
5 i16 Short value. Not impl.
6 reg Ordinarily register.
7 ireg Index register.
8 xreg Extended register.
Valid arg-specifiers for DMC 2 compilers are all those that are implemented.
User's Manual 5.1 Inmotion Technologies AB
Doc. No.9032 0027 01 (B), Rev. 11.07.2001