[GHC] #16233: HIE file generation is inefficient

[GHC]

#16233: HIE file generation is inefficient
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        Reporter:  harpocrates       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.7
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #15320            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"5ed48d25decc9dec29659482644b136cff91606e/ghc"
 5ed48d25/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="5ed48d25decc9dec29659482644b136cff91606e"
 Include type info for only some exprs in HIE files

 This commit relinquishes some some type information in `.hie` files in
 exchange for better performance. See #16233 for more on this.

 Using `.hie` files to generate hyperlinked sources is a crucial milestone
 towards Hi Haddock (the initiative to move Haddock to work over `.hi`
 files and embed docstrings in those). Unfortunately, even after much
 optimization on the Haddock side, the `.hie` based solution is still
 considerably slower and more memory hungry than the existing
 implementation
 - and the @.hie@ code is to blame.

 This changes `.hie` file generation to track type information for only
 a limited subset of expressions (specifically, those that might eventually
 turn into hyperlinks in the Haddock's hyperlinker backend).
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16233#comment:4>
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