Macro Instruction Arguments

• Parameters referred to as dummy or macro instruction arguments are used to define the macro.

• Instead than using macro calls, the macro facility can insert blocks of instructions. Any given macro's calls will all be replaced with blocks that are exactly the same.

• There is no method for a single macro call to alter the code that replaces it, which limits the versatility of this macro feature. Including arguments, or parameters, in macro calls is a significant development of this feature.

• The definitions of macros will have corresponding macro dummy arguments.

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A  1, VALUE 1
A  2, VALUE 1
A  3, VALUE 1
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A  1, VALUE 2
A  2, VALUE 2
A  3, VALUE 1
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VALUE 1  DC F'7'
VALUE 2  DC F'14'

• The sequence mentioned above is fairly similar but not exact. The first sequence uses the operand DATA1 for its operation, whereas the second uses VALUE 2 for its operation.

• Therefore, the arguments are defined in the macro definition together with the macro name, and the statement in the body uses these arguments in place of data.

• VALUE 1 is the parameter in the first macro call INCR VALUE 1, and VALUE 2 is the argument given in the second macro call.

• They may be thought of as carrying out the same action with a varied input or parameter. A macro instruction argument, often known as a dummy argument, is one such parameter. The ampersand, which is always the first character, serves as a distinguishing feature and is supplied on the macro name line.