[GHC] #14287: Early inlining causes potential join points to be missed

[GHC]

#14287: Early inlining causes potential join points to be missed
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        Reporter:  jheek             |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by mpickering):

 How are you compiling, with which version of the compiler? All 3
 `filterTest`s were csed to the same definition when I tried with my
 modified compiler.

 Here is the test file and results.

 https://gist.github.com/7c7cb362206f60bc85a76ceb30d786c3

 Observe that in the `loopification.simpl` dump file, all 3 are CSEd but in
 `no-loopification.simpl` only 1 and 3 are CSEd.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14287#comment:5>
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