Moduleghc-9.10.3GHC2021

GHC.Driver.Plugins

Definitions for writing plugins for GHC. Plugins can hook into several areas of the compiler. See the Plugin type. These plugins include type-checker plugins, source plugins, and core-to-core plugins.

17 types
14 values

Packageghc-9.10.3
Exports31
LanguageGHC2021
LicenceBSD-3-Clause
SourcePlugins.hs

Plugins

7 declarations

datadata Plugins

Constructors

Plugins
- staticPlugins :: ![StaticPlugin]
  Static plugins which do not need dynamic loading. These plugins are intended to be added by GHC API users directly to this list.
  To add dynamically loaded plugins through the GHC API see addPluginModuleName instead.
- externalPlugins :: ![ExternalPlugin]
  External plugins loaded directly from libraries without loading module interfaces.
- loadedPlugins :: ![LoadedPlugin]
  Plugins dynamically loaded after processing arguments. What will be loaded here is directed by DynFlags.pluginModNames. Arguments are loaded from DynFlags.pluginModNameOpts.
  The purpose of this field is to cache the plugins so they don't have to be loaded each time they are needed. See initializePlugins.
- loadedPluginDeps :: !([Linkable], PkgsLoaded)
  The object files required by the loaded plugins See Note [Plugin dependencies]

valueemptyPlugins :: Plugins

datadata Plugin

Plugin is the compiler plugin data type. Try to avoid constructing one of these directly, and just modify some fields of defaultPlugin instead: this is to try and preserve source-code compatibility when we add fields to this.

Nonetheless, this API is preliminary and highly likely to change in the future.

Constructors

Plugin
- installCoreToDos :: CorePlugin
  Modify the Core pipeline that will be used for compilation. This is called as the Core pipeline is built for every module being compiled, and plugins get the opportunity to modify the pipeline in a nondeterministic order.
- tcPlugin :: TcPlugin
  An optional typechecker plugin, which may modify the behaviour of the constraint solver.
- defaultingPlugin :: DefaultingPlugin
  An optional defaulting plugin, which may specify the additional type-defaulting rules.
- holeFitPlugin :: HoleFitPlugin
  An optional plugin to handle hole fits, which may re-order or change the list of valid hole fits and refinement hole fits.
- driverPlugin :: [CommandLineOption] -> HscEnv -> IO HscEnv
  An optional plugin to update HscEnv, right after plugin loading. This can be used to register hooks or tweak any field of DynFlags before doing actual work on a module.
- latePlugin :: LatePlugin
  A plugin that runs after interface creation and after late cost centre insertion. Useful for transformations that should not impact interfaces or optimization at all.
- pluginRecompile :: [CommandLineOption] -> IO PluginRecompile
  Specify how the plugin should affect recompilation.
- parsedResultAction :: [CommandLineOption] -> ModSummary -> ParsedResult -> Hsc ParsedResult
  Modify the module when it is parsed. This is called by GHC.Driver.Main when the parser has produced no or only non-fatal errors. Compilation will fail if the messages produced by this function contain any errors.
- renamedResultAction :: [CommandLineOption] -> TcGblEnv -> HsGroup GhcRn -> TcM (TcGblEnv, HsGroup GhcRn)
  Modify each group after it is renamed. This is called after each HsGroup has been renamed.
- typeCheckResultAction :: [CommandLineOption] -> ModSummary -> TcGblEnv -> TcM TcGblEnv
  Modify the module when it is type checked. This is called at the very end of typechecking.
- spliceRunAction :: [CommandLineOption] -> LHsExpr GhcTc -> TcM (LHsExpr GhcTc)
  Modify the TH splice or quasiqoute before it is run.
- interfaceLoadAction :: forall lcl. [CommandLineOption] -> ModIface -> IfM lcl ModIface
  Modify an interface that have been loaded. This is called by GHC.Iface.Load when an interface is successfully loaded. Not applied to the loading of the plugin interface. Tools that rely on information from modules other than the currently compiled one should implement this function.

valuedefaultPlugin :: Plugin

Default plugin: does nothing at all, except for marking that safe inference has failed unless -fplugin-trustworthy is passed. For compatibility reason you should base all your plugin definitions on this default value.

typetype CommandLineOption = String

Command line options gathered from the -PModule.Name:stuff syntax are given to you as this type

datadata PsMessages

Errors and warnings produced by the parser

Constructors

PsMessages
- psWarnings :: Messages PsWarning
- psErrors :: Messages PsError

datadata ParsedResult

Result of running the parser and the parser plugin

Constructors

ParsedResult
- parsedResultModule :: HsParsedModule
  Parsed module, potentially modified by a plugin
- parsedResultMessages :: PsMessages
  Warnings and errors from parser, potentially modified by a plugin

External plugins

1 declaration

valueloadExternalPlugins :: [ExternalPluginSpec] -> IO [ExternalPlugin]

Load external plugins

Recompilation checking

valuepurePlugin :: [CommandLineOption] -> IO PluginRecompile

valueimpurePlugin :: [CommandLineOption] -> IO PluginRecompile

valueflagRecompile :: [CommandLineOption] -> IO PluginRecompile

datadata PluginRecompile

Constructors

ForceRecompile
NoForceRecompile
MaybeRecompile Fingerprint

Instances3Semigroup, Monoid, Outputable

Semigroup PluginRecompileDefined in ghc-9.10.3 · GHC.Driver.Plugins
Monoid PluginRecompileDefined in ghc-9.10.3 · GHC.Driver.Plugins
Outputable PluginRecompileDefined in ghc-9.10.3 · GHC.Driver.Plugins

Plugin types

0 declarations

Frontend plugins

datadata FrontendPlugin

Constructors

FrontendPlugin
- frontend :: FrontendPluginAction

valuedefaultFrontendPlugin :: FrontendPlugin

typetype FrontendPluginAction = [String] -> [(String, Maybe Phase)] -> Ghc ()

Core plugins

Core plugins allow plugins to register as a Core-to-Core pass.

typetype CorePlugin = [CommandLineOption] -> [CoreToDo] -> CoreM [CoreToDo]

Typechecker plugins

Typechecker plugins allow plugins to provide evidence to the typechecker.

typetype TcPlugin = [CommandLineOption] -> Maybe TcPlugin

Source plugins

GHC offers a number of points where plugins can access and modify its front-end ("source") representation. These include:

access to the parser result with parsedResultAction
access to the renamed AST with renamedResultAction
access to the typechecked AST with typeCheckResultAction
access to the Template Haskell splices with spliceRunAction
access to loaded interface files with interfaceLoadAction

valuekeepRenamedSource

A renamer plugin which mades the renamed source available in a typechecker plugin.

Defaulting plugins

Defaulting plugins can add candidate types to the defaulting mechanism.

typetype DefaultingPlugin = [CommandLineOption] -> Maybe DefaultingPlugin

Hole fit plugins

hole fit plugins allow plugins to change the behavior of valid hole fit suggestions

datadata HoleFitPluginR

HoleFitPluginR adds a TcRef to hole fit plugins so that plugins can track internal state. Note the existential quantification, ensuring that the state cannot be modified from outside the plugin.

Late plugins

Late plugins can access and modify the core of a module after optimizations have been applied and after interface creation.

typetype LatePlugin = HscEnv -> [CommandLineOption] -> (CgGuts, CostCentreState) -> IO (CgGuts, CostCentreState)

Internal

10 declarations

datadata PluginWithArgs

Constructors

PluginWithArgs
- paPlugin :: Plugin
  the actual callable plugin
- paArguments :: [CommandLineOption]
  command line arguments for the plugin

valuepluginsWithArgs :: Plugins -> [PluginWithArgs]

valuepluginRecompile' :: PluginWithArgs -> IO PluginRecompile

datadata LoadedPlugin

A plugin with its arguments. The result of loading the plugin.

Constructors

LoadedPlugin
- lpPlugin :: PluginWithArgs
  the actual plugin together with its commandline arguments
- lpModule :: ModIface
  the module containing the plugin

valuelpModuleName :: LoadedPlugin -> ModuleName

datadata StaticPlugin

A static plugin with its arguments. For registering compiled-in plugins through the GHC API.

Constructors

StaticPlugin
- spPlugin :: PluginWithArgs
  the actual plugin together with its commandline arguments

datadata ExternalPlugin

External plugin loaded directly from a library without loading module interfaces

Constructors

ExternalPlugin
- epPlugin :: PluginWithArgs
  Plugin with its arguments
- epUnit :: String
  UnitId
- epModule :: String
  Module name

valuemapPlugins :: Plugins -> (Plugin -> [CommandLineOption] -> a) -> [a]

valuewithPlugins :: Monad m => Plugins -> PluginOperation m a -> a -> m a

Perform an operation by using all of the plugins in turn.

valuewithPlugins_ :: Monad m => Plugins -> ConstPluginOperation m a -> a -> m ()

Perform a constant operation by using all of the plugins in turn.