• Ben Gamari's avatar
    Clean up handling of known-key Names in interface files · 34d933d6
    Ben Gamari authored
    Previously BinIface had some dedicated logic for handling tuple names in
    the symbol table. As it turns out, this logic was essentially dead code
    as it was superceded by the special handling of known-key things. Here
    we cull the tuple code-path and use the known-key codepath for all
    tuple-ish things.
    This had a surprising number of knock-on effects,
     * constraint tuple datacons had to be made known-key (previously they
       were not)
     * IfaceTopBndr was changed from being a synonym of OccName to a
       synonym of Name (since we now need to be able to deserialize Names
       directly from interface files)
     * the change to IfaceTopBndr complicated fingerprinting, since we need
       to ensure that we don't go looking for the fingerprint of the thing
       we are currently fingerprinting in the fingerprint environment (see
       notes in MkIface). Handling this required distinguishing between
       binding and non-binding Name occurrences in the Binary serializers.
     * the original name cache logic which previously lived in IfaceEnv has
       been moved to a new NameCache module
     * I ripped tuples and sums out of knownKeyNames since they introduce a
       very large number of entries. During interface file deserialization
       we use static functions (defined in the new KnownUniques module) to
       map from a Unique to a known-key Name (the Unique better correspond
       to a known-key name!) When we need to do an original name cache
       lookup we rely on the parser implemented in isBuiltInOcc_maybe.
     * HscMain.allKnownKeyNames was folded into PrelInfo.knownKeyNames.
     * Lots of comments were sprinkled about describing the new scheme.
    Updates haddock submodule.
    Test Plan: Validate
    Reviewers: niteria, simonpj, austin, hvr
    Reviewed By: simonpj
    Subscribers: simonmar, niteria, thomie
    Differential Revision: https://phabricator.haskell.org/D2467
    GHC Trac Issues: #12532, #12415
Unique.hs 14.3 KB