[GHC] #13442: Add a coercion/cast operator to CMM

[GHC]

#13442: Add a coercion/cast operator to CMM
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        Reporter:  erikd             |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.0.1
      Resolution:  invalid           |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by rwbarton):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 Replying to [comment:10 erikd]:
 > Thinking about it some more, I can't see how CMM could represent a
 casting operation without the `CmmCast` expression I added.

 Let's please not add a generic casting operation to Cmm. We already have a
 variety of specific conversions; and the whole point here is that it is
 not easy to implement the specific conversion that you need (as in
 ticket:4092#comment:9).

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13442#comment:12>
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