gas now supports macros

gas now supports macros

[Ian Lance Taylor]

I have added support for macros to gas.  I did it by integrating some
of the code from gasp.

I wouldn't describe this as particularly complete, but it does seem to
work.  I would be interested in getting reactions, patches, and
suggestions for improvement.  It would be particularly nice if
somebody figured out a good way to put macro expansions into a
assembler listing.

Ian

Sample usage:

        .macro  sum from=0, to=5
        .long   \from
        .if     \to-\from
        sum     "(\from+1)",\to
        .endif
        .endm