[GHC] #11486: info tables are no longer aligned

[GHC]

#11486: info tables are no longer aligned
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        Reporter:  rwbarton          |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  high              |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  8.1
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1847
       Wiki Page:                    |
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Comment (by rwbarton):

 This had a small, but mostly beneficial effect on performance:
 https://perf.haskell.org/ghc/#revision/0dc7b36c3c261b3eccf8460581fcd3d71f6e6ff6

 As expected, there is a code size cost, which has an indirect performance
 cost as well (since density of real code in the instruction cache is
 lower).

 Not exactly germane to this ticket, but perhaps it would be worth
 experimenting with half-word-aligned info tables? Many of the info table
 fields are half-word-sized anyways.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11486#comment:9>
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