[Git][ghc/ghc][master] Document IfaceTupleTy

[Marge Bot]

 Marge Bot pushed to branch master at Glasgow Haskell Compiler / GHC


Commits:
da8f4ddd by Richard Eisenberg at 2020-09-17T01:28:38-04:00
Document IfaceTupleTy

- - - - -


1 changed file:

- compiler/GHC/Iface/Type.hs


Changes:

=====================================
compiler/GHC/Iface/Type.hs
=====================================
@@ -176,6 +176,11 @@ data IfaceType
        PromotionFlag                 -- A bit like IfaceTyCon
        IfaceAppArgs               -- arity = length args
           -- For promoted data cons, the kind args are omitted
+          -- Why have this? Only for efficiency: IfaceTupleTy can omit the
+          -- type arguments, as they can be recreated when deserializing.
+          -- In an experiment, removing IfaceTupleTy resulted in a 0.75% regression
+          -- in interface file size (in GHC's boot libraries).
+          -- See !3987.
 
 type IfaceMult = IfaceType
 



View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/da8f4ddd76bac18c721aeaa247725953604206d3

-- 
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/da8f4ddd76bac18c721aeaa247725953604206d3
You're receiving this email because of your account on gitlab.haskell.org.


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/ghc-commits/attachments/20200917/006c1510/attachment.html>