[GHC] #7847: Maintain per-generation lists of weak pointers

[GHC]

#7847: Maintain per-generation lists of weak pointers
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    Reporter:  akio              |       Owner:                              
        Type:  feature request   |      Status:  infoneeded                  
    Priority:  normal            |   Milestone:                              
   Component:  Runtime System    |     Version:  7.7                         
    Keywords:                    |          Os:  Unknown/Multiple            
Architecture:  Unknown/Multiple  |     Failure:  Compile-time performance bug
  Difficulty:  Unknown           |    Testcase:                              
   Blockedby:                    |    Blocking:                              
     Related:                    |  
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Comment(by akio):

 Thank you for review.

 Replying to [comment:9 simonmar]:
 > patch 0001 looks good to me.
 >
 > On patch 0002:
 >
 > * Why do we have `dead_weak_ptr_list_tail` rather than just consing new
 items on the front of the list?

 This is a trace of an earlier design that survived by accident. I'll clean
 it up in a few days.

 >
 > If you haven't already, I recommend testing these patches with
 `libraries/base/tests/memo001.hs` and `libraries/base/tests/memo002.hs`.
 Those are pretty good stress tests of the weak pointer implementation.

 Yes, the patches passed these tests (and the rest of validation).

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7847#comment:10>
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