[GHC] #1434: Missing RULEs for truncate

[GHC]

#1434: Missing RULEs for truncate
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    Reporter:  ghc@…                      |        Owner:                         
        Type:  task                       |       Status:  patch                  
    Priority:  low                        |    Milestone:  7.0.1                  
   Component:  libraries/base             |      Version:  6.4.1                  
    Keywords:  rules                      |     Testcase:                         
   Blockedby:                             |   Difficulty:  Unknown                
          Os:  Unknown/Multiple           |     Blocking:                         
Architecture:  Unknown/Multiple           |      Failure:  Runtime performance bug
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Changes (by daniel.is.fischer):

  * status:  new => patch


Comment:

 Patch with rewrite rules for the sized Int and Word types whose ranges are
 contained in Int's range. Unfortunately, we can't have a rule for Word
 here, that would need its own primop to improve much on the default
 implementation. It doesn't depend on #2271, but it will only help with
 truncate without it.

 Please review and merge.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1434#comment:21>
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