[GHC] #12900: Common up identical info tables

[GHC]

#12900: Common up identical info tables
-------------------------------------+-------------------------------------
        Reporter:  dobenour          |                Owner:
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by osa1):

 We discussed this on the IRC channel and @ezyang pointed out two things:

 - Assuming this is only for merging same info tables, we can go even
 further by
   reordering fields so that {{{data T1 = T1 Int# Bool}}} and {{{data T2 =
 T2
   Bool Int#}}} would get same info tables. This obviously needs a lot more
 work
   but saves more space.

 - This breaks {{{-h}}} which works even in non-profiled mode.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12900#comment:2>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler