{-# LANGUAGE DataKinds #-} {-# LANGUAGE TypeFamilies #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE FlexibleInstances #-} {-# LANGUAGE UndecidableInstances #-} module GHC.Unit.Module.ModIface ( ModIface , ModIface_ (..) , PartialModIface , ModIfaceBackend (..) , IfaceDeclExts , IfaceBackendExts , IfaceExport , WhetherHasOrphans , WhetherHasFamInst , mi_boot , mi_fix , mi_semantic_module , mi_free_holes , mi_mnwib , renameFreeHoles , emptyPartialModIface , emptyFullModIface , mkIfaceHashCache , emptyIfaceHashCache , forceModIface ) where import GHC.Prelude import GHC.Hs import GHC.Iface.Syntax import GHC.Iface.Ext.Fields import GHC.Unit import GHC.Unit.Module.Deps import GHC.Unit.Module.Warnings import GHC.Types.Avail import GHC.Types.Fixity import GHC.Types.Fixity.Env import GHC.Types.HpcInfo import GHC.Types.Name import GHC.Types.Name.Reader import GHC.Types.SafeHaskell import GHC.Types.SourceFile import GHC.Types.Unique.DSet import GHC.Types.Unique.FM import GHC.Data.Maybe import GHC.Utils.Fingerprint import GHC.Utils.Binary import Control.DeepSeq import Control.Exception {- Note [Interface file stages] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Interface files have two possible stages. * A partial stage built from the result of the core pipeline. * A fully instantiated form. Which also includes fingerprints and potentially information provided by backends. We can build a full interface file two ways: * Directly from a partial one: Then we omit backend information and mostly compute fingerprints. * From a partial one + information produced by a backend. Then we store the provided information and fingerprint both. -} type PartialModIface = ModIface_ 'ModIfaceCore type ModIface = ModIface_ 'ModIfaceFinal -- | Extends a PartialModIface with information which is either: -- * Computed after codegen -- * Or computed just before writing the iface to disk. (Hashes) -- In order to fully instantiate it. data ModIfaceBackend = ModIfaceBackend { mi_iface_hash :: !Fingerprint -- ^ Hash of the whole interface , mi_mod_hash :: !Fingerprint -- ^ Hash of the ABI only , mi_flag_hash :: !Fingerprint -- ^ Hash of the important flags used when compiling the module, excluding -- optimisation flags , mi_opt_hash :: !Fingerprint -- ^ Hash of optimisation flags , mi_hpc_hash :: !Fingerprint -- ^ Hash of hpc flags , mi_plugin_hash :: !Fingerprint -- ^ Hash of plugins , mi_orphan :: !WhetherHasOrphans -- ^ Whether this module has orphans , mi_finsts :: !WhetherHasFamInst -- ^ Whether this module has family instances. See Note [The type family -- instance consistency story]. , mi_exp_hash :: !Fingerprint -- ^ Hash of export list , mi_orphan_hash :: !Fingerprint -- ^ Hash for orphan rules, class and family instances combined -- Cached environments for easy lookup. These are computed (lazily) from -- other fields and are not put into the interface file. -- Not really produced by the backend but there is no need to create them -- any earlier. , mi_warn_fn :: !(OccName -> Maybe (WarningTxt GhcRn)) -- ^ Cached lookup for 'mi_warns' , mi_fix_fn :: !(OccName -> Maybe Fixity) -- ^ Cached lookup for 'mi_fixities' , mi_hash_fn :: !(OccName -> Maybe (OccName, Fingerprint)) -- ^ Cached lookup for 'mi_decls'. The @Nothing@ in 'mi_hash_fn' means that -- the thing isn't in decls. It's useful to know that when seeing if we are -- up to date wrt. the old interface. The 'OccName' is the parent of the -- name, if it has one. } data ModIfacePhase = ModIfaceCore -- ^ Partial interface built based on output of core pipeline. | ModIfaceFinal -- | Selects a IfaceDecl representation. -- For fully instantiated interfaces we also maintain -- a fingerprint, which is used for recompilation checks. type family IfaceDeclExts (phase :: ModIfacePhase) where IfaceDeclExts 'ModIfaceCore = IfaceDecl IfaceDeclExts 'ModIfaceFinal = (Fingerprint, IfaceDecl) type family IfaceBackendExts (phase :: ModIfacePhase) where IfaceBackendExts 'ModIfaceCore = () IfaceBackendExts 'ModIfaceFinal = ModIfaceBackend -- | A 'ModIface' plus a 'ModDetails' summarises everything we know -- about a compiled module. The 'ModIface' is the stuff *before* linking, -- and can be written out to an interface file. The 'ModDetails is after -- linking and can be completely recovered from just the 'ModIface'. -- -- When we read an interface file, we also construct a 'ModIface' from it, -- except that we explicitly make the 'mi_decls' and a few other fields empty; -- as when reading we consolidate the declarations etc. into a number of indexed -- maps and environments in the 'ExternalPackageState'. -- -- See Note [Strictness in ModIface] to learn about why some fields are -- strict and others are not. data ModIface_ (phase :: ModIfacePhase) = ModIface { mi_module :: !Module, -- ^ Name of the module we are for mi_sig_of :: !(Maybe Module), -- ^ Are we a sig of another mod? mi_hsc_src :: !HscSource, -- ^ Boot? Signature? mi_deps :: Dependencies, -- ^ The dependencies of the module. This is -- consulted for directly-imported modules, but not -- for anything else (hence lazy) mi_usages :: [Usage], -- ^ Usages; kept sorted so that it's easy to decide -- whether to write a new iface file (changing usages -- doesn't affect the hash of this module) -- NOT STRICT! we read this field lazily from the interface file -- It is *only* consulted by the recompilation checker mi_exports :: ![IfaceExport], -- ^ Exports -- Kept sorted by (mod,occ), to make version comparisons easier -- Records the modules that are the declaration points for things -- exported by this module, and the 'OccName's of those things mi_used_th :: !Bool, -- ^ Module required TH splices when it was compiled. -- This disables recompilation avoidance (see #481). mi_fixities :: [(OccName,Fixity)], -- ^ Fixities -- NOT STRICT! we read this field lazily from the interface file mi_warns :: (Warnings GhcRn), -- ^ Warnings -- NOT STRICT! we read this field lazily from the interface file mi_anns :: [IfaceAnnotation], -- ^ Annotations -- NOT STRICT! we read this field lazily from the interface file mi_decls :: [IfaceDeclExts phase], -- ^ Type, class and variable declarations -- The hash of an Id changes if its fixity or deprecations change -- (as well as its type of course) -- Ditto data constructors, class operations, except that -- the hash of the parent class/tycon changes mi_globals :: !(Maybe GlobalRdrEnv), -- ^ Binds all the things defined at the top level in -- the /original source/ code for this module. which -- is NOT the same as mi_exports, nor mi_decls (which -- may contains declarations for things not actually -- defined by the user). Used for GHCi and for inspecting -- the contents of modules via the GHC API only. -- -- (We need the source file to figure out the -- top-level environment, if we didn't compile this module -- from source then this field contains @Nothing@). -- -- Strictly speaking this field should live in the -- 'HomeModInfo', but that leads to more plumbing. -- Instance declarations and rules mi_insts :: [IfaceClsInst], -- ^ Sorted class instance mi_fam_insts :: [IfaceFamInst], -- ^ Sorted family instances mi_rules :: [IfaceRule], -- ^ Sorted rules mi_hpc :: !AnyHpcUsage, -- ^ True if this program uses Hpc at any point in the program. mi_trust :: !IfaceTrustInfo, -- ^ Safe Haskell Trust information for this module. mi_trust_pkg :: !Bool, -- ^ Do we require the package this module resides in be trusted -- to trust this module? This is used for the situation where a -- module is Safe (so doesn't require the package be trusted -- itself) but imports some trustworthy modules from its own -- package (which does require its own package be trusted). -- See Note [Trust Own Package] in GHC.Rename.Names mi_complete_matches :: ![IfaceCompleteMatch], mi_docs :: Maybe Docs, -- ^ Docstrings and related data for use by haddock, the ghci -- @:doc@ command, and other tools. -- -- @Just _@ @<=>@ the module was built with @-haddock@. mi_final_exts :: !(IfaceBackendExts phase), -- ^ Either `()` or `ModIfaceBackend` for -- a fully instantiated interface. mi_ext_fields :: !ExtensibleFields, -- ^ Additional optional fields, where the Map key represents -- the field name, resulting in a (size, serialized data) pair. -- Because the data is intended to be serialized through the -- internal `Binary` class (increasing compatibility with types -- using `Name` and `FastString`, such as HIE), this format is -- chosen over `ByteString`s. -- mi_src_hash :: !Fingerprint -- ^ Hash of the .hs source, used for recompilation checking. } {- Note [Strictness in ModIface] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The ModIface is the Haskell representation of an interface (.hi) file. * During compilation we write out ModIface values to disk for files that we have just compiled * For packages that we depend on we load the ModIface from disk. Some fields in the ModIface are deliberately lazy because when we read an interface file we don't always need all the parts. For example, an interface file contains information about documentation which is often not needed during compilation. This is achieved using the lazyPut/lazyGet pair. If the field was strict then we would pointlessly load this information into memory. On the other hand, if we create a ModIface but **don't** write it to disk then to avoid space leaks we need to make sure to deepseq all these lazy fields because the ModIface might live for a long time (for instance in a GHCi session). That's why in GHC.Driver.Main.hscMaybeWriteIface there is the call to forceModIface. -} -- | Old-style accessor for whether or not the ModIface came from an hs-boot -- file. mi_boot :: ModIface -> IsBootInterface mi_boot iface = if mi_hsc_src iface == HsBootFile then IsBoot else NotBoot mi_mnwib :: ModIface -> ModuleNameWithIsBoot mi_mnwib iface = GWIB (moduleName $ mi_module iface) (mi_boot iface) -- | Lookups up a (possibly cached) fixity from a 'ModIface'. If one cannot be -- found, 'defaultFixity' is returned instead. mi_fix :: ModIface -> OccName -> Fixity mi_fix iface name = mi_fix_fn (mi_final_exts iface) name `orElse` defaultFixity -- | The semantic module for this interface; e.g., if it's a interface -- for a signature, if 'mi_module' is @p[A=]:A@, 'mi_semantic_module' -- will be @@. mi_semantic_module :: ModIface_ a -> Module mi_semantic_module iface = case mi_sig_of iface of Nothing -> mi_module iface Just mod -> mod -- | The "precise" free holes, e.g., the signatures that this -- 'ModIface' depends on. mi_free_holes :: ModIface -> UniqDSet ModuleName mi_free_holes iface = case getModuleInstantiation (mi_module iface) of (_, Just indef) -- A mini-hack: we rely on the fact that 'renameFreeHoles' -- drops things that aren't holes. -> renameFreeHoles (mkUniqDSet cands) (instUnitInsts (moduleUnit indef)) _ -> emptyUniqDSet where cands = dep_sig_mods $ mi_deps iface -- | Given a set of free holes, and a unit identifier, rename -- the free holes according to the instantiation of the unit -- identifier. For example, if we have A and B free, and -- our unit identity is @p[A=,B=impl:B]@, the renamed free -- holes are just C. renameFreeHoles :: UniqDSet ModuleName -> [(ModuleName, Module)] -> UniqDSet ModuleName renameFreeHoles fhs insts = unionManyUniqDSets (map lookup_impl (uniqDSetToList fhs)) where hmap = listToUFM insts lookup_impl mod_name | Just mod <- lookupUFM hmap mod_name = moduleFreeHoles mod -- It wasn't actually a hole | otherwise = emptyUniqDSet -- See Note [Strictness in ModIface] about where we use lazyPut vs put instance Binary ModIface where put_ bh (ModIface { mi_module = mod, mi_sig_of = sig_of, mi_hsc_src = hsc_src, mi_src_hash = _src_hash, -- Don't `put_` this in the instance -- because we are going to write it -- out separately in the actual file mi_deps = deps, mi_usages = usages, mi_exports = exports, mi_used_th = used_th, mi_fixities = fixities, mi_warns = warns, mi_anns = anns, mi_decls = decls, mi_insts = insts, mi_fam_insts = fam_insts, mi_rules = rules, mi_hpc = hpc_info, mi_trust = trust, mi_trust_pkg = trust_pkg, mi_complete_matches = complete_matches, mi_docs = docs, mi_ext_fields = _ext_fields, -- Don't `put_` this in the instance so we -- can deal with it's pointer in the header -- when we write the actual file mi_final_exts = ModIfaceBackend { mi_iface_hash = iface_hash, mi_mod_hash = mod_hash, mi_flag_hash = flag_hash, mi_opt_hash = opt_hash, mi_hpc_hash = hpc_hash, mi_plugin_hash = plugin_hash, mi_orphan = orphan, mi_finsts = hasFamInsts, mi_exp_hash = exp_hash, mi_orphan_hash = orphan_hash }}) = do put_ bh mod put_ bh sig_of put_ bh hsc_src put_ bh iface_hash put_ bh mod_hash put_ bh flag_hash put_ bh opt_hash put_ bh hpc_hash put_ bh plugin_hash put_ bh orphan put_ bh hasFamInsts lazyPut bh deps lazyPut bh usages put_ bh exports put_ bh exp_hash put_ bh used_th put_ bh fixities lazyPut bh warns lazyPut bh anns put_ bh decls put_ bh insts put_ bh fam_insts lazyPut bh rules put_ bh orphan_hash put_ bh hpc_info put_ bh trust put_ bh trust_pkg put_ bh complete_matches lazyPutMaybe bh docs get bh = do mod <- get bh sig_of <- get bh hsc_src <- get bh iface_hash <- get bh mod_hash <- get bh flag_hash <- get bh opt_hash <- get bh hpc_hash <- get bh plugin_hash <- get bh orphan <- get bh hasFamInsts <- get bh deps <- lazyGet bh usages <- {-# SCC "bin_usages" #-} lazyGet bh exports <- {-# SCC "bin_exports" #-} get bh exp_hash <- get bh used_th <- get bh fixities <- {-# SCC "bin_fixities" #-} get bh warns <- {-# SCC "bin_warns" #-} lazyGet bh anns <- {-# SCC "bin_anns" #-} lazyGet bh decls <- {-# SCC "bin_tycldecls" #-} get bh insts <- {-# SCC "bin_insts" #-} get bh fam_insts <- {-# SCC "bin_fam_insts" #-} get bh rules <- {-# SCC "bin_rules" #-} lazyGet bh orphan_hash <- get bh hpc_info <- get bh trust <- get bh trust_pkg <- get bh complete_matches <- get bh docs <- lazyGetMaybe bh return (ModIface { mi_module = mod, mi_sig_of = sig_of, mi_hsc_src = hsc_src, mi_src_hash = fingerprint0, -- placeholder because this is dealt -- with specially when the file is read mi_deps = deps, mi_usages = usages, mi_exports = exports, mi_used_th = used_th, mi_anns = anns, mi_fixities = fixities, mi_warns = warns, mi_decls = decls, mi_globals = Nothing, mi_insts = insts, mi_fam_insts = fam_insts, mi_rules = rules, mi_hpc = hpc_info, mi_trust = trust, mi_trust_pkg = trust_pkg, -- And build the cached values mi_complete_matches = complete_matches, mi_docs = docs, mi_ext_fields = emptyExtensibleFields, -- placeholder because this is dealt -- with specially when the file is read mi_final_exts = ModIfaceBackend { mi_iface_hash = iface_hash, mi_mod_hash = mod_hash, mi_flag_hash = flag_hash, mi_opt_hash = opt_hash, mi_hpc_hash = hpc_hash, mi_plugin_hash = plugin_hash, mi_orphan = orphan, mi_finsts = hasFamInsts, mi_exp_hash = exp_hash, mi_orphan_hash = orphan_hash, mi_warn_fn = mkIfaceWarnCache warns, mi_fix_fn = mkIfaceFixCache fixities, mi_hash_fn = mkIfaceHashCache decls }}) -- | The original names declared of a certain module that are exported type IfaceExport = AvailInfo emptyPartialModIface :: Module -> PartialModIface emptyPartialModIface mod = ModIface { mi_module = mod, mi_sig_of = Nothing, mi_hsc_src = HsSrcFile, mi_src_hash = fingerprint0, mi_deps = noDependencies, mi_usages = [], mi_exports = [], mi_used_th = False, mi_fixities = [], mi_warns = NoWarnings, mi_anns = [], mi_insts = [], mi_fam_insts = [], mi_rules = [], mi_decls = [], mi_globals = Nothing, mi_hpc = False, mi_trust = noIfaceTrustInfo, mi_trust_pkg = False, mi_complete_matches = [], mi_docs = Nothing, mi_final_exts = (), mi_ext_fields = emptyExtensibleFields } emptyFullModIface :: Module -> ModIface emptyFullModIface mod = (emptyPartialModIface mod) { mi_decls = [] , mi_final_exts = ModIfaceBackend { mi_iface_hash = fingerprint0, mi_mod_hash = fingerprint0, mi_flag_hash = fingerprint0, mi_opt_hash = fingerprint0, mi_hpc_hash = fingerprint0, mi_plugin_hash = fingerprint0, mi_orphan = False, mi_finsts = False, mi_exp_hash = fingerprint0, mi_orphan_hash = fingerprint0, mi_warn_fn = emptyIfaceWarnCache, mi_fix_fn = emptyIfaceFixCache, mi_hash_fn = emptyIfaceHashCache } } -- | Constructs cache for the 'mi_hash_fn' field of a 'ModIface' mkIfaceHashCache :: [(Fingerprint,IfaceDecl)] -> (OccName -> Maybe (OccName, Fingerprint)) mkIfaceHashCache pairs = \occ -> lookupOccEnv env occ where env = foldl' add_decl emptyOccEnv pairs add_decl env0 (v,d) = foldl' add env0 (ifaceDeclFingerprints v d) where add env0 (occ,hash) = extendOccEnv env0 occ (occ,hash) emptyIfaceHashCache :: OccName -> Maybe (OccName, Fingerprint) emptyIfaceHashCache _occ = Nothing -- Take care, this instance only forces to the degree necessary to -- avoid major space leaks. instance (NFData (IfaceBackendExts (phase :: ModIfacePhase)), NFData (IfaceDeclExts (phase :: ModIfacePhase))) => NFData (ModIface_ phase) where rnf (ModIface f1 f2 f3 f4 f5 f6 f7 f8 f9 f10 f11 f12 f13 f14 f15 f16 f17 f18 f19 f20 f21 f22 f23) = rnf f1 `seq` rnf f2 `seq` f3 `seq` f4 `seq` f5 `seq` f6 `seq` rnf f7 `seq` f8 `seq` f9 `seq` rnf f10 `seq` rnf f11 `seq` f12 `seq` rnf f13 `seq` rnf f14 `seq` rnf f15 `seq` rnf f16 `seq` f17 `seq` rnf f18 `seq` rnf f19 `seq` f20 `seq` f21 `seq` f22 `seq` rnf f23 `seq` () instance NFData (ModIfaceBackend) where rnf (ModIfaceBackend f1 f2 f3 f4 f5 f6 f7 f8 f9 f10 f11 f12 f13) = rnf f1 `seq` rnf f2 `seq` rnf f3 `seq` rnf f4 `seq` rnf f5 `seq` rnf f6 `seq` rnf f7 `seq` rnf f8 `seq` rnf f9 `seq` rnf f10 `seq` rnf f11 `seq` rnf f12 `seq` rnf f13 forceModIface :: ModIface -> IO () forceModIface iface = () <$ (evaluate $ force iface) -- | Records whether a module has orphans. An \"orphan\" is one of: -- -- * An instance declaration in a module other than the definition -- module for one of the type constructors or classes in the instance head -- -- * A rewrite rule in a module other than the one defining -- the function in the head of the rule -- type WhetherHasOrphans = Bool -- | Does this module define family instances? type WhetherHasFamInst = Bool