[GHC] #1498: Optimisation: eliminate unnecessary heap check in recursive function

[GHC]

#1498: Optimisation: eliminate unnecessary heap check in recursive function
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    Reporter:  simonmar                    |       Owner:                         
        Type:  bug                         |      Status:  new                    
    Priority:  normal                      |   Milestone:  7.4.1                  
   Component:  Compiler                    |     Version:  6.6.1                  
    Keywords:                              |          Os:  Unknown/Multiple       
Architecture:  Unknown/Multiple            |     Failure:  Runtime performance bug
  Difficulty:  Moderate (less than a day)  |    Testcase:                         
   Blockedby:  4258                        |    Blocking:                         
     Related:                              |  
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Changes (by rl):

  * failure:  None/Unknown => Runtime performance bug
  * type:  task => bug


Comment:

 This is actually biting high-performance code with the LLVM backend quite
 badly. I'm not sure if and how the new codegen will affect the LLVM
 backend but this is one of the top reasons for suboptimal loop performance
 right now.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1498#comment:9>
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