[GHC] #13960: Ticks exhausted with 8.0.2

[GHC]

#13960: Ticks exhausted with 8.0.2
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        Reporter:  tom-bop           |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        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:                    |
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Comment (by bgamari):

 Thanks tom-bop!

 What is happening here is that GHC is inlining the guts of `toStrict
 (toLazyByteString x)` into each call site of `fromString` (since this is
 what `bytestring` requests). In the case that we are calling `fromString`
 on a dynamically computed `String` this might make sense since we could
 possibly fuse the encoding logic and buffer write into the producer.

 However, in this particular case the `String` is a literal (that is,
 produced by `unpackCString#`). I really don't think there is any good
 reason to inline here. Moreover, in principle `Builder` should handle
 string literals with a simple `memcpy`. Unfortunately, it can't currently
 do this (easily) since string literals don't have an exposed size and we
 treat `'\0'` a bit funnily (encoding it as `'\xC0\x80'`, which the
 `memcpy` would need to undo).

 Ultimately I think the right solution would be to simply treat literals
 properly.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13960#comment:12>
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