[GHC] #8158: Replace IO manager's IntMap with a mutable hash table

[GHC]

#8158: Replace IO manager's IntMap with a mutable hash table
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        Reporter:  bos         |            Owner:
            Type:  feature     |           Status:  patch
  request                      |        Milestone:  7.8.1
        Priority:  normal      |          Version:  7.7
       Component:              |         Keywords:
  libraries/base               |     Architecture:  Unknown/Multiple
      Resolution:              |       Difficulty:  Easy (less than 1 hour)
Operating System:              |       Blocked By:
  Unknown/Multiple             |  Related Tickets:
 Type of failure:  Other       |
       Test Case:              |
        Blocking:              |
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Comment (by hvr):

 ...what's the benefit of using a `ForeignPtr Int` over `IORef Int` in

 {{{#!hs
 data IT a = IT { tabArr  :: {-# UNPACK #-} !(Arr (Bucket a))
                , tabSize :: {-# UNPACK #-} !(ForeignPtr Int)
                }
 }}}

 ?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8158#comment:4>
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