[GHC] #12367: Commit adding instances to GHC.Generics regression compiler performance

[GHC]

#12367: Commit adding instances to GHC.Generics regression compiler performance
-------------------------------------+-------------------------------------
        Reporter:  bgamari           |                Owner:  bgamari
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.0.2
       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:                    |
-------------------------------------+-------------------------------------

@@ -4,1 +4,1 @@
- compile time) by about 10%.
+ compile time) by between 0 and 20% (on average about 5%).

New description:

 Recently 673efccb3b348e9daf23d9e65460691bbea8586e added a number of new
 instances for types defined in `GHC.Generics`. Unfortunately, it seems
 that this has regressed nofib compilation allocations (and also, it seems,
 compile time) by between 0 and 20% (on average about 5%).

--

Comment (by bgamari):

 ||= Test name =||= Absolute change =||= relative change =||
 || compile-allocs/MyList             || 20238384 ||     0.208624775040415
 ||
 || compile-allocs/MyList             || 20281496 ||     0.206217801180845
 ||
 || compile-allocs/Prog               || 20334192 ||     0.202959317331712
 ||
 || compile-allocs/Prog               || 20344656 ||      0.20053198007393
 ||
 || compile-allocs/Basics             || 22115840 ||     0.185615422473695
 ||
 || compile-allocs/Basics             || 22149816 ||     0.183089910175923
 ||
 || compile-allocs/Assemble_loadvec   || 20347184 ||     0.166966893079396
 ||
 || compile-allocs/Digraph            || 21606168 ||     0.166243308385695
 ||
 || compile-allocs/Assemble_loadvec   || 20357600 ||     0.165346296105217
 ||
 || compile-allocs/Shows              || 20296024 ||     0.165204453781781
 ||
 || compile-allocs/Digraph            || 21659944 ||     0.165084805640568
 ||
 || compile-allocs/Shows              || 20338616 ||     0.163719820616552
 ||
 || compile-allocs/Tol_cal            || 20737568 ||     0.161829271665394
 ||
 || compile-allocs/Queue              || 20579112 ||     0.161181557853612
 ||
 || compile-allocs/Tol_cal            || 20731568 ||     0.160175008827888
 ||
 || compile-allocs/Queue              || 20600368 ||     0.159599282181737
 ||
 || compile-allocs/Vtslib             || 20374904 ||     0.155144898631996
 ||
 || compile-allocs/Match              || 20975896 ||     0.154183839207216
 ||
 || compile-allocs/Vtslib             || 20368168 ||     0.153618623974637
 ||
 || compile-allocs/Match              || 21000088 ||     0.152948131340001
 ||
 || compile-allocs/Preds              || 20369168 ||     0.150245373920468
 ||
 || compile-allocs/Preds              || 20382840 ||      0.14899133906394
 ||
 || compile-allocs/BinConv            || 21814376 ||     0.147565217236013
 ||
 || compile-allocs/BinConv            || 21843560 ||     0.146507544982022
 ||
 || compile-allocs/Shapes             || 20121512 ||     0.144706659929922
 ||

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12367#comment:1>
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