[GHC] #14677: Code generator does not correctly tag a pointer

[GHC]

#14677: Code generator does not correctly tag a pointer
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:  14626
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by heisenbug):

 Replying to [comment:20 alexbiehl]:
 > Gabor,
 >
 > see https://github.com/ghc/ghc/blob/master/rts/StgMiscClosures.cmm#L268.
 Take the indirectee, untag and enter. (Btw. why do we untag the value and
 enter, wouldn't we want to just return R1 if it is tagged?)

 So `StgInd_indirectee` grabs the value `evtWrite1_r3aU_closure+1` (why the
 two zeroes behind that???).

 If we (could?) know that `evtWrite_closure` just redirects to that, why
 not perform the redirection at Cmm-gen time? The unfolding TMPL surely
 gives a hint how to do it!

 >
 > edit: (entering the indirectee makes sense to reduce chains of
 IND_STATICs to the static value)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14677#comment:21>
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