[GHC] #14490: TTG Snags

[GHC]

#14490: TTG Snags
-------------------------------------+-------------------------------------
        Reporter:  alanz             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14482            |  Differential Rev(s):
       Wiki Page:                    |
  ImplementingTreesThatGrow          |
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Comment (by alanz):

 I agree on Plan C.

 But I am currently concerned that the major slowdown is not just from the
 instances.

 I understand bgamari is going to revert the TTG commits, and there is now
 a detailed timing flag
 (https://phabricator.haskell.org/rGHC2da7813b771edcb3efb1b067b986d10f5de4beaf)
 which we will be able to use to compare the compilation time for the
 before and after versions.

 This should at least give us an idea of where the major impacts are coming
 from, in terms of modules.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14490#comment:3>
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