Split GHC.Driver.Types

I was working on making DynFlags stateless (#17957), especially by
storing loaded plugins into HscEnv instead of DynFlags. It turned out to
be complicated because HscEnv is in GHC.Driver.Types but LoadedPlugin
isn't: it is in GHC.Driver.Plugins which depends on GHC.Driver.Types. I
didn't feel like introducing yet another hs-boot file to break the loop.

Additionally I remember that while we introduced the module hierarchy
(#13009) we talked about splitting GHC.Driver.Types because it contained
various unrelated types and functions, but we never executed. I didn't
feel like making GHC.Driver.Types bigger with more unrelated Plugins
related types, so finally I bit the bullet and split GHC.Driver.Types.

As a consequence this patch moves a lot of things. I've tried to put
them into appropriate modules but nothing is set in stone.

Several other things moved to avoid loops.

* Removed Binary instances from GHC.Utils.Binary for random compiler
  things
* Moved Typeable Binary instances into GHC.Utils.Binary.Typeable: they
  import a lot of things that users of GHC.Utils.Binary don't want to
  depend on.
* put everything related to Units/Modules under GHC.Unit:
  GHC.Unit.Finder, GHC.Unit.Module.{ModGuts,ModIface,Deps,etc.}
* Created several modules under GHC.Types: GHC.Types.Fixity, SourceText,
  etc.
* Split GHC.Utils.Error (into GHC.Types.Error)
* Finally removed GHC.Driver.Types

Note that this patch doesn't put loaded plugins into HscEnv. It's left
for another patch.

Bump haddock submodule

1 files changed, 54 insertions, 0 deletions

diff --git a/compiler/GHC/Unit/Module/Imported.hs b/compiler/GHC/Unit/Module/Imported.hs
new file mode 100644
index 0000000000..d6cd3ac88f
--- /dev/null
+++ b/compiler/GHC/Unit/Module/Imported.hs
@@ -0,0 +1,54 @@
+module GHC.Unit.Module.Imported
+   ( ImportedMods
+   , ImportedBy (..)
+   , ImportedModsVal (..)
+   , importedByUser
+   )
+where
+
+import GHC.Prelude
+
+import GHC.Unit.Module
+
+import GHC.Types.Name.Reader
+import GHC.Types.SafeHaskell
+import GHC.Types.SrcLoc
+
+-- | Records the modules directly imported by a module for extracting e.g.
+-- usage information, and also to give better error message
+type ImportedMods = ModuleEnv [ImportedBy]
+
+-- | If a module was "imported" by the user, we associate it with
+-- more detailed usage information 'ImportedModsVal'; a module
+-- imported by the system only gets used for usage information.
+data ImportedBy
+    = ImportedByUser ImportedModsVal
+    | ImportedBySystem
+
+importedByUser :: [ImportedBy] -> [ImportedModsVal]
+importedByUser (ImportedByUser imv : bys) = imv : importedByUser bys
+importedByUser (ImportedBySystem   : bys) =       importedByUser bys
+importedByUser [] = []
+
+data ImportedModsVal = ImportedModsVal
+   { imv_name        :: ModuleName
+      -- ^ The name the module is imported with
+
+   , imv_span        :: SrcSpan
+      -- ^ the source span of the whole import
+
+   , imv_is_safe     :: IsSafeImport
+      -- ^ whether this is a safe import
+
+   , imv_is_hiding   :: Bool
+      -- ^ whether this is an "hiding" import
+
+   , imv_all_exports :: !GlobalRdrEnv
+      -- ^ all the things the module could provide.
+      --
+      -- NB. BangPattern here: otherwise this leaks. (#15111)
+
+   , imv_qualified   :: Bool
+      -- ^ whether this is a qualified import
+   }
+