-ffast-math and floating point reordering

[law@redhat.com]

In message <4064721A.6060905@tat.physik.uni-tuebingen.de>, Richard Guenther wri
tes:
 >> Yeah.  We sort of discussed adding additional PLUS_EXPR operands and/or
 >> attributes at last year's summit.  But I think that was the extent of
 >> it.  IIRC, there was beer involved, so I doubt anybody was taking notes.
 >
 >Hmm, this is usually the point where we get the LLVM people tell us what 
 >they are doing here...  I consider not being able to do something about 
 >this in tree-ssa a major defect, too.
Well, given that the front-ends don't even provide this information at this
time, I don't consider it a defect.  I consider it a long term enhancement
we need to add first to the front-ends, then to the SSA bits.

jeff