[commit: ghc] ghc-7.10: Fix a long-standing bug in the demand analyser (37f928a)

[git at git.haskell.org]

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

On branch  : ghc-7.10
Link       : http://ghc.haskell.org/trac/ghc/changeset/37f928aa8bb55f888ca6e22ec9f8605f695d0b44/ghc

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commit 37f928aa8bb55f888ca6e22ec9f8605f695d0b44
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Apr 6 14:10:52 2015 +0100

    Fix a long-standing bug in the demand analyser
    
    This patch fixes Trac #10148, an outright and egregious
    bug in the demand analyser.
    
    It is explained in Note [Demand on case-alternative binders]
    in Demand.hs.
    
    I did some other minor refactoring.
    
    To my astonishment I got some big compiler perf changes
    
    * perf/compiler/T5837: bytes allocated -76%
    * perf/compiler/T5030: bytes allocated -10%
    * perf/compiler/T3294: max bytes used  -25%
    
    Happy days
    
    (cherry picked from commit 9f0f99fd41ff82cc223d3b682703e508efb564d2)


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37f928aa8bb55f888ca6e22ec9f8605f695d0b44
 compiler/basicTypes/Demand.hs |  58 ++++++++++++-
 compiler/stranal/DmdAnal.hs   | 194 ++++++++++++++++++++++++------------------
 2 files changed, 165 insertions(+), 87 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 37f928aa8bb55f888ca6e22ec9f8605f695d0b44