Small clean up and barrier performance improvements
Small clean up and barrier performance improvements

- Removed unnecessary on clauses in set up

- Replaced the forall in the inner loop of the backwards pass with a
  for+on.  In terms of communication counts, this is the best thing
  for now, and possibly even for the longer term depending on the
  ultimate performance of the reduction.

- Added on clauses to the barrier code to combine the forks for the 2
  atomics and also to avoid repeated forks for the wait()



git-svn-id: 88467cb1fb04b8a755be7e1ee1026be4190196ef@19850 3a8e244f-b0f2-452b-bcba-4c88e055c3ca

sungeunchoi/chapel,CoryMcCartan/chapel,chizarlicious/chapel,hildeth/chapel,chizarlicious/chapel,sungeunchoi/chapel,chizarlicious/chapel,CoryMcCartan/chapel,CoryMcCartan/chapel,CoryMcCartan/chapel,hildeth/chapel,sungeunchoi/chapel,sungeunchoi/chapel,chizarlicious/chapel,CoryMcCartan/chapel,hildeth/chapel,sungeunchoi/chapel,chizarlicious/chapel,hildeth/chapel,hildeth/chapel,hildeth/chapel,sungeunchoi/chapel,sungeunchoi/chapel,chizarlicious/chapel,sungeunchoi/chapel,CoryMcCartan/chapel,hildeth/chapel,chizarlicious/chapel,CoryMcCartan/chapel