PATCH: string-expansion macros

[Doug Evans]

Greg McGary writes:
 > fche@redhat.com (Frank Ch. Eigler) writes:
 > 
 > > : I'd like to know why the old code tried to match macros before hard
 > > : insns?  The reason I need to try hard insns before macros is that for
 > > : my MIPS-like port, string macros catch cases that can't be handled by
 > > : one insn, and implement a "virtual insn" that do things in 2 or 3 hard
 > > : insns.  [...]
 > >
 > > Yes, this makes sense in most cases, but methinks there are other
 > > opposite cases also.
 > 
 > Can you think of an example?

One way I think of macro insns is as being intercepts/wrappers
for real insns.  If you don't do the intercepts first, you ain't
gonna get the effect you want.

I think that's the way things should work,
and I wonder if needing to reverse it reveals a problem that
is best solved differently.

Note that macros were originally intended to support emitting
code rather than doing text transformation.