[GHC] #7574: Register allocator chokes on certain branches with literals

[GHC]

#7574: Register allocator chokes on certain branches with literals
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    Reporter:  thoughtpolice     |       Owner:  thoughtpolice     
        Type:  bug               |      Status:  new               
    Priority:  high              |   Milestone:  7.8.1             
   Component:  Compiler (NCG)    |     Version:  7.7               
    Keywords:  ncg, codegen      |          Os:  Unknown/Multiple  
Architecture:  Unknown/Multiple  |     Failure:  Compile-time crash
  Difficulty:  Unknown           |    Testcase:                    
   Blockedby:  7573              |    Blocking:                    
     Related:  #7571,#7534       |  
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Comment(by simonmar):

 @thoughtpolice - I presume you got stalled?  I looked into this myself and
 somehow couldn't get my fix to work properly, the NCG was throwing away
 code that it shouldn't have been.  I shall try again when I get some time,
 but it definitely needs fixing before 7.8.1.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7574#comment:16>
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