[tree-ssa] Small dominator optimizer compile-time improvement

[law@redhat.com]

In message <9E904FC8-8D81-11D8-B711-000A95967F9E@physics.uc.edu>, Andrew Pinski
 writes:
 >On Apr 12, 2004, at 16:02, law@redhat.com wrote:
 >> Bootstrapped and regression tested.
 >
 >For some reason this patch causes my bootstrap to fail on 
 >i686-pc-linux-gnu.
 >I use the mainline GCC as the stage1 compiler and CVS binutils.  The 
 >machine
 >has 1GB of memory and it stops in the same place each time.
Seems to work fine for me.  Regardless, I'm not going to have time to 
analyze this before I leave tomorrow.  I've reverted both of my commits
to tree-ssa-dom.c from 2004/04/12.

Jeff