[commit: ghc] wip/ttg-next: Use Plan B for deriving Data Instances (0d06dad)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : wip/ttg-next
Link       : http://ghc.haskell.org/trac/ghc/changeset/0d06dad00a0b3de9ad5257b9a98c2e66f01eb3ec/ghc

>---------------------------------------------------------------

commit 0d06dad00a0b3de9ad5257b9a98c2e66f01eb3ec
Author: Alan Zimmerman <alan.zimm at gmail.com>
Date:   Mon Apr 2 23:38:59 2018 +0200

    Use Plan B for deriving Data Instances
    
    https://ghc.haskell.org/trac/ghc/wiki/ImplementingTreesThatGrow/Instances#PLANB
    
    Illustrative numbers
    
    Compiling HsInstances before using Plan B.
    
    Max residency ~ 5G
    <<ghc: 629,864,691,176 bytes, 5300 GCs,
           321075437/1087762592 avg/max bytes residency (23 samples),
           2953M in use, 0.000 INIT (0.000 elapsed),
           383.511 MUT (384.986 elapsed), 37.426 GC (37.444 elapsed) :ghc>>
    
    Using Plan B
    
    Max residency 1.1G
    
    <<ghc: 78,832,782,968 bytes, 2884 GCs,
           222140352/386470152 avg/max bytes residency (34 samples),
           1062M in use, 0.001 INIT (0.001 elapsed),
           56.612 MUT (62.917 elapsed), 32.974 GC (32.923 elapsed) :ghc>>


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0d06dad00a0b3de9ad5257b9a98c2e66f01eb3ec
 compiler/hsSyn/HsInstances.hs | 430 +++++++++++++++++++++++++++++++++++-------
 compiler/hsSyn/HsSyn.hs       |   6 +-
 2 files changed, 366 insertions(+), 70 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 0d06dad00a0b3de9ad5257b9a98c2e66f01eb3ec