[GHC] #3744: Comparisons against minBound/maxBound not optimised for (Int|Word)(8|16|32)

[GHC]

#3744: Comparisons against minBound/maxBound not optimised for (Int|Word)(8|16|32)
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        Reporter:  rl                |                   Owner:
            Type:  feature request   |                  Status:  new
        Priority:  low               |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  6.13
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Changes (by rwbarton):

 * cc: rwbarton (added)


Comment:

 I just ran into this too. Perhaps the thing to do is to generate rules in
 PrelRules like
 {{{
     narrow8IntOp x < 127 = True
 }}}
 etc.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/3744#comment:19>
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