11.1: Single-Line Macros
- Page ID
- 19925
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There are two key types of macros; single-line macros and multi-line macros. Each of these is described in the following sections.
Single-line macros are defined using the %define directive. The definitions work in a similar way to C/C++; so you can do things like:
%define mulby4(x) shl x, 2
And, then use the macro by entering:
mulby4 (rax)
in the source, which will multiply the contents to the rax register by 4 (via shifting two bits).