[GHC] #8317: Optimize tagToEnum# at Core level

[GHC]

#8317: Optimize tagToEnum# at Core level
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        Reporter:  jstolarek         |            Owner:
            Type:  task              |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.7
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:  8326
        Blocking:                    |  Related Tickets:  #6135
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Comment (by Jan Stolarek <jan.stolarek@…>):

 In [changeset:53948f915140396acd1b80c6a7a252b2d1e12635/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="53948f915140396acd1b80c6a7a252b2d1e12635"
 Restore old names of comparison primops

 In 6579a6c we removed existing comparison primops and introduced new ones
 returning Int# instead of Bool. This commit (and associated commits in
 array, base, dph, ghc-prim, integer-gmp, integer-simple, primitive,
 testsuite and
 template-haskell) restores old names of primops. This allows us to keep
 our API cleaner at the price of not having backwards compatibility.

 This patch also temporalily disables fix for #8317 (optimization of
 tagToEnum# at Core level). We need to fix #8326 first, otherwise
 our primops code will be very slow.
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8317#comment:3>
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