Fuse long and FP compare & condition on x86/x86-64 in Optimizing.

This is a preliminary implementation of fusing long/float/double
compares with conditions to avoid materializing the result from the
compare and condition.

The information from a HCompare is transferred to the HCondition if it
is legal.  There must be only a single use of the HCompare, the HCompare
and HCondition must be in the same block, the HCondition must not need

Added GetOppositeCondition() to HCondition to return the flipped

Bug: 21120453
Change-Id: I1f1db206e6dc336270cd71070ed3232dedc754d6
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>
12 files changed