[GHC] #13344: Core string literal patch regresses compiler performance considerably

[GHC]

#13344: Core string literal patch regresses compiler performance considerably
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        Reporter:  bgamari           |                Owner:  bgamari
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by bgamari):

 * owner:  (none) => bgamari
 * failure:  None/Unknown => Compile-time performance bug
 * priority:  normal => high


Old description:

> The Core string literals patch regresses compiler performance by nearly
> 5%.
> https://perf.haskell.org/ghc/#revision/d49b2bb21691892ca6ac8f2403e31f2a5e53feb3
>
> We should really understand why this is; this is a huge regression for
> something that really shouldn't be costly.

New description:

 The Core string literals patch
 [[https://perf.haskell.org/ghc/#revision/d49b2bb21691892ca6ac8f2403e31f2a5e53feb3|regresses]]
 compiler performance by nearly 5%.

 We should really understand why this is; this is a huge regression for
 something that really shouldn't be costly.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13344#comment:1>
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