patch applied (ghc): Fix #3170: Allow coalescing of the same node during register allocation.

[Ben Lippmeier]

Sat Apr 18 01:22:53 PDT 2009  Ben.Lippmeier at anu.edu.au
  * Fix #3170: Allow coalescing of the same node during register allocation.
  Ignore-this: b3a14959d7616fd53c3334a4f0b30f48
    The x86 code generator sometimes generates nop moves like
    movl %vI_a %vI_a, but we'll just ignore them for coalescing
    purposes instead of emitting an error. It shouldn't hurt anything.

    M ./compiler/utils/GraphOps.hs -3 +3

View patch online:
http://darcs.haskell.org/ghc/_darcs/patches/20090418082253-43c66-44fb2cd6210457fa3f100a63be5a480e985d1474.gz