54

Chapter 8. Assembler Directives

8.58.

.list

Control (in conjunction with the

.nolist

directive) whether or not assembly listings are generated.

These two directives maintain an internal counter (which is zero initially).

.list

increments the

counter, and

.nolist

decrements it. Assembly listings are generated whenever the counter is greater

than zero.

By default, listings are disabled. When you enable them (with the

 a

command line option; Chapter

3 Command Line Options), the initial value of the listing counter is one.

8.59.

.long expressions

.long

is the same as

.int

, Section 8.48

.int expressions

.

8.60.

.macro

The commands

.macro

and

.endm

allow you to define macros that generate assembly output. For

example, this definition specifies a macro

sum

that puts a sequence of numbers into memory:

.macro

sum from=0, to=5

.long

\from

.if

\to \from

sum

"(\from+1)",\to

.endif

.endm

With that definition,

SUM 0,5

is equivalent to this assembly input:

.long

0

.long

1

.long

2

.long

3

.long

4

.long

5

.macro macname

.macro macname macargs ...

Begin the definition of a macro called

macname

. If your macro definition requires arguments,

specify their names after the macro name, separated by commas or spaces. You can supply a

default value for any macro argument by following the name with

=deflt

. For example, these

are all valid

.macro

statements:

.macro comm

Begin the definition of a macro called

comm

, which takes no arguments.

.macro plus1 p, p1

.macro plus1 p p1

Either statement begins the definition of a macro called

plus1

, which takes two arguments;

within the macro definition, write

\p

or

\p1

to evaluate the arguments.