PATCH to emit smlal/umlal for arm

[Jeffrey A Law]

  In message < 199912142150.VAA28234@cam-mail1.cambridge.arm.com >you write:
  > > >> > 
  > > >> > 
  > > >> > 1999-12-10  Clinton Popetz  <cpopetz@cygnus.com>
  > > >> > 
  > > >> > 	* config/arm/arm.md (mulsidi3adddi, umulsidi3adddi): New patter
  > ns
  > > >> > 	for long long multiply-accumlate.
  > > >> 
  > > >> This should have been applied to the merged-arm-thumb-backend-branch. 
  > > >> TARGET_ARM is not valid on the trunk, so it won't compile.
  > > >
  > > >Sorry.  I backed this out and applied it to the branch.
  > > >
  > > 
  > > On Nick's request, I also took out the TARGET_ARM and committed this to t
  > he
  > > trunk.
  > > 				-Clint
  > 
  > How on earth did you back out the previous change?  The CVS log is showing 
  > the head revision of arm.md as 1.40 and the date for this is today, but 
  > 1.40 was the head revision on Saturday when I updated then.
  > 
  > Please don't say you've used cvs admin -o to obsolete the head revision of 
  > a cvs file!
That is indeed what happened.  According to Clint that was SOP at his previous
job when they needed to back out an incorrect change.

Clint -- the right way to back out a change is to re-apply the patch (which
has the effect of un-doing the patch) and check in the result.

  One reason cvs admin -o is considered bad is we can't recreate the sources
  for a particular date.  ie, consider the case where we check in a change C
  on day 1.   On day 5 we realize change C was bad and cvs admin -o it out of
  the repository.  That means we can not recreate the precise state of the
  source tree for day 1 ... day 5 -- which is something we do need to do on a
  fairly regular basis.

Anyway, I'll cobble up something to add to cvswrite.html so that folks won't
make this mistake in the future.

jeff