[GHC] #13861: Take more advantage of STG representation invariance (follows up #9291)

[GHC]

#13861: Take more advantage of STG representation invariance (follows up #9291)
-------------------------------------+-------------------------------------
        Reporter:  heisenbug         |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.2
      Resolution:                    |             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:                    |
-------------------------------------+-------------------------------------

Comment (by simonpj):

 If the paper doesn't say and there are no comments to explain, the last
 port of call would be Simon Marlow.  Otherwise I'd assume it was just
 becuase it seemed like the easiest thing, and most data types are smaller.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13861#comment:8>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler