[commit: ghc] ghc-8.4: Fix join-point decision (20afdaa)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/20afdaa75e269697c2f9608e6d29f720a6387d01/ghc

>---------------------------------------------------------------

commit 20afdaa75e269697c2f9608e6d29f720a6387d01
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Tue Jan 9 13:53:09 2018 +0000

    Fix join-point decision
    
    This patch moves the "ok_unfolding" test
       from  CoreOpt.joinPointBinding_maybe
       to    OccurAnal.decideJoinPointHood
    
    Previously the occurrence analyser was deciding to make
    something a join point, but the simplifier was reversing
    that decision, which made the decision about /other/ bindings
    invalid.
    
    Fixes Trac #14650.
    
    (cherry picked from commit 66ff794fedf6e81e727dc8f651e63afe6f2a874b)


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20afdaa75e269697c2f9608e6d29f720a6387d01
 compiler/coreSyn/CoreOpt.hs                        | 44 +------------
 compiler/simplCore/OccurAnal.hs                    | 68 +++++++++++++++----
 testsuite/tests/simplCore/should_compile/T14650.hs | 76 ++++++++++++++++++++++
 testsuite/tests/simplCore/should_compile/all.T     |  1 +
 4 files changed, 136 insertions(+), 53 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 20afdaa75e269697c2f9608e6d29f720a6387d01