c/7949: [3.2/3.3 regression] Mishandling of double != 0.0 at -O1

[Janis Johnson]

The regression showed up with this patch:

Tue Feb 19 12:37:23 CET 2002  Jan Hubicka  <jh@suse.cz>

        * regmove.c (regmove_optimize): Avoid increasing of
        register pressure.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=7949