big slowdown in egcs-1.1.2->gcc-2.95 on alpha

[Jeffrey A Law]

  In message < 199908070139.CAA18804@phal.cygnus.co.uk >you write:
  > Hmm, I wonder if the CONFLICT_P tests take a lot of time, or if the rest
  > of the operations in the inner loop cost more.
  > 
  > I wonder if this works:
  > 
  > Thu Aug  5 22:27:15 1999  J"orn Rennecke <amylaar@cygnus.co.uk>
  > 
  > 	* global.c (prune_preferences): Move some invariants out of the
  > 	inner loop.
This patch is fine, even if it did not make a significant difference for
the compile time slowdown in question.   Thanks.
jeff