[GHC] #13745: Investigate compile-time regressions in regex-tdfa-1.2.2

[GHC]

#13745: Investigate compile-time regressions in regex-tdfa-1.2.2
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  high              |            Milestone:  8.2.2
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by dfeuer):

 I was able to get enough to compare the results of `LiberateCase`. Things
 generally look the same at the top level, but after the `SetLevels` patch
 there's a bunch more local code. Everything is rather huge, so it's hard
 to see just what the deal is, but interestingly it really seems to be
 ''added'' code more than ''replaced'' code. Virtually everything that used
 to be there is still there, but now there's more. I'll attach diffable
 dump files.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13745#comment:12>
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