[GHC] #7450: Regression in optimisation time of functions with many patterns (6.12 to 7.4)?

[GHC]

#7450: Regression in optimisation time of functions with many patterns (6.12 to
7.4)?
-------------------------------------------+--------------------------------
  Reporter:  iustin                        |          Owner:                  
      Type:  bug                           |         Status:  new             
  Priority:  normal                        |      Milestone:                  
 Component:  Compiler                      |        Version:  7.6.1           
Resolution:                                |       Keywords:                  
        Os:  Unknown/Multiple              |   Architecture:  Unknown/Multiple
   Failure:  Compile-time performance bug  |     Difficulty:  Unknown         
  Testcase:                                |      Blockedby:                  
  Blocking:                                |        Related:                  
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Comment(by simonpj):

 OK with these changes I now get this:

 ||  ||6.12.3||  6.12.3||        HEAD||  HEAD||
 ||#constructors||       Alloc (Mbytes)||        Time (s)||      Alloc
 (Mbytes)  ||Time (s)||
 ||40    ||      || ||   1075||  1.7||
 ||80    ||1646||        4||     2184    ||5||
 ||160|| 3217    ||8     ||4862  ||10||
 ||320   ||6385  ||16    ||12242 ||23||
 ||640|| 12766   ||34||  35009|| 60||

 So it still looks quite a bit less well-behaved than 6.12.3, for reasons I
 don't yet understand.  But better than before.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7450#comment:6>
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