[GHC] #11645: Heap profiling - hp2ps: samples out of sequence

[GHC]

#11645: Heap profiling - hp2ps: samples out of sequence
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        Reporter:  thomie            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Profiling         |              Version:  8.0.1-rc2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
                                     |  libraries/hpc/tests/fork/hpc_fork
      Blocked By:                    |             Blocking:
 Related Tickets:  #664              |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by angerman):

 Ohh, i'm super sorry, not to have attached my reorder script.

 {{{#!haskell
 {-# LANGUAGE LambdaCase #-}

 import System.Environment (getArgs)

 import Data.List (mapAccumL, isPrefixOf)
 import GHC.Exts (sortWith)

 main :: IO ()
 main = getArgs >>= \case
   [f] -> readFile f >>= pure . unlines . reorder . lines >>= putStr
   _   -> putStrLn $ "only one input"

 reorder :: [String] -> [String]
 reorder = map snd . sortWith fst . snd . mapAccumL f (-1.0)
   where
     g :: (Double, String) -> (Double, (Double, String))
     g (x,y) = (x,(x,y))
     f :: Double -> String -> (Double, (Double, String))
     f acc line
       | "BEGIN_SAMPLE " `isPrefixOf` line = g (read $ drop 13 line, line)
       | "END_SAMPLE " `isPrefixOf` line && (read $ drop 11 line) /= acc =
 error "BEING/END missmatch"
       | otherwise                         = g (acc, line)
 }}}

 Could have saved someone else some time :(

 However, the generated output still looks rather garbled.
 [[Image(https://dl.dropbox.com/s/yz5d5ug656mziun/Screenshot%202017-10-03%2017.15.58.png)]]

 did you observe the same Fuuzetsu?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11645#comment:9>
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