[GHC] #13344: Core string literal patch regresses compiler performance considerably

[GHC]

#13344: Core string literal patch regresses compiler performance considerably
-------------------------------------+-------------------------------------
        Reporter:  bgamari           |                Owner:  bgamari
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.1
      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:                    |
-------------------------------------+-------------------------------------

Comment (by bgamari):

 Reid and I had a rather lengthy discussion about this problem. The take-
 away message is that while there are a variety of things that we could do
 to avoid moving string literals up to the top-level (and consequently
 avoid the costs associated with interface file names, as seen in
 comment:10), it is unfortunately rather tricky to do in a way that doesn't
 either come at significant implementation cost or risk regressing #12585.

 Consequently, we came up with a few ideas for instead reducing the cost of
 the now-larger interface files. Happily, this effort may also have helpful
 effects beyond string literals. The gist is that we want make interface
 file deserialisation more lazy. Reid is working on a patch.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13344#comment:15>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler