[GHC] #11295: Figure out what LLVM passes are fruitful

[GHC]

#11295: Figure out what LLVM passes are fruitful
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        Reporter:  bgamari           |                Owner:  kavon
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (LLVM)   |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by kavon):

 Ben, I think the autotuner is now ready to be applied to Haskell programs:
 it can successfully tune C/C++ programs, with or without running the
 output program, to match -O3 in a reasonable time.

 If it's not too late, I can try to get something in for 8.4. My plan is to
 pick a few "representative" programs*, tune on each one individually, and
 see which pass ordering does the best across nofib. If one of them does
 better than the -Ox passes, we could drop it in GHC pretty easily.

 What do you think?

 * Suggestions are welcome here. Infrastructure to tune against the
 "average" of several programs (using a special objective function) would
 be ideal, but that infrastructure is not ready yet.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11295#comment:14>
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