Safe Haskell	None
Language	GHC2021

GHC.Driver.Plugins

Contents

Plugins
External plugins
- Recompilation checking
Plugin types
Internal

Description

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.

Synopsis

data Plugins = Plugins {
- staticPlugins :: ![StaticPlugin]
- externalPlugins :: ![ExternalPlugin]
- loadedPlugins :: ![LoadedPlugin]
- loadedPluginDeps :: !([Linkable], PkgsLoaded)
}
emptyPlugins :: Plugins
data Plugin = Plugin {
- installCoreToDos :: CorePlugin
- tcPlugin :: TcPlugin
- defaultingPlugin :: DefaultingPlugin
- holeFitPlugin :: HoleFitPlugin
- driverPlugin :: [CommandLineOption] -> HscEnv -> IO HscEnv
- latePlugin :: LatePlugin
- pluginRecompile :: [CommandLineOption] -> IO PluginRecompile
- parsedResultAction :: [CommandLineOption] -> ModSummary -> ParsedResult -> Hsc ParsedResult
- renamedResultAction :: [CommandLineOption] -> TcGblEnv -> HsGroup GhcRn -> TcM (TcGblEnv, HsGroup GhcRn)
- typeCheckResultAction :: [CommandLineOption] -> ModSummary -> TcGblEnv -> TcM TcGblEnv
- spliceRunAction :: [CommandLineOption] -> LHsExpr GhcTc -> TcM (LHsExpr GhcTc)
- interfaceLoadAction :: forall lcl. [CommandLineOption] -> ModIface -> IfM lcl ModIface
}
defaultPlugin :: Plugin
type CommandLineOption = String
data PsMessages = PsMessages {
- psWarnings :: Messages PsWarning
- psErrors :: Messages PsError
}
data ParsedResult = ParsedResult {
- parsedResultModule :: HsParsedModule
- parsedResultMessages :: PsMessages
}
loadExternalPlugins :: [ExternalPluginSpec] -> IO [ExternalPlugin]
purePlugin :: [CommandLineOption] -> IO PluginRecompile
impurePlugin :: [CommandLineOption] -> IO PluginRecompile
flagRecompile :: [CommandLineOption] -> IO PluginRecompile
data PluginRecompile
- = ForceRecompile
- | NoForceRecompile
- | MaybeRecompile Fingerprint
data FrontendPlugin = FrontendPlugin {
- frontend :: FrontendPluginAction
}
defaultFrontendPlugin :: FrontendPlugin
type FrontendPluginAction = [String] -> [(String, Maybe Phase)] -> Ghc ()
type CorePlugin = [CommandLineOption] -> [CoreToDo] -> CoreM [CoreToDo]
type TcPlugin = [CommandLineOption] -> Maybe TcPlugin
keepRenamedSource :: [CommandLineOption] -> TcGblEnv -> HsGroup GhcRn -> TcM (TcGblEnv, HsGroup GhcRn)
type DefaultingPlugin = [CommandLineOption] -> Maybe DefaultingPlugin
data HoleFitPluginR
type LatePlugin = HscEnv -> [CommandLineOption] -> (CgGuts, CostCentreState) -> IO (CgGuts, CostCentreState)
data PluginWithArgs = PluginWithArgs {
- paPlugin :: Plugin
- paArguments :: [CommandLineOption]
}
pluginsWithArgs :: Plugins -> [PluginWithArgs]
pluginRecompile' :: PluginWithArgs -> IO PluginRecompile
data LoadedPlugin = LoadedPlugin {
- lpPlugin :: PluginWithArgs
- lpModule :: ModIface
}
lpModuleName :: LoadedPlugin -> ModuleName
data StaticPlugin = StaticPlugin {
- spPlugin :: PluginWithArgs
- spInitialised :: Bool
}
data ExternalPlugin = ExternalPlugin {
- epPlugin :: PluginWithArgs
- epUnit :: String
- epModule :: String
}
mapPlugins :: Plugins -> (Plugin -> [CommandLineOption] -> a) -> [a]
withPlugins :: Monad m => Plugins -> PluginOperation m a -> a -> m a
withPlugins_ :: Monad m => Plugins -> ConstPluginOperation m a -> a -> m ()

Plugins

data Plugins Source #

Constructors

Plugins

Fields

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]

emptyPlugins :: Plugins Source #

data Plugin Source #

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

Fields

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.
Since: ghc-8.10.1
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.
Since: ghc-9.10.1
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.

defaultPlugin :: Plugin Source #

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.

type CommandLineOption = String Source #

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

data PsMessages Source #

Errors and warnings produced by the parser

Constructors

PsMessages
Fields psWarnings :: Messages PsWarning psErrors :: Messages PsError

data ParsedResult Source #

Result of running the parser and the parser plugin

Constructors

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

External plugins

loadExternalPlugins :: [ExternalPluginSpec] -> IO [ExternalPlugin] Source #

Load external plugins

Recompilation checking

purePlugin :: [CommandLineOption] -> IO PluginRecompile Source #

impurePlugin :: [CommandLineOption] -> IO PluginRecompile Source #

flagRecompile :: [CommandLineOption] -> IO PluginRecompile Source #

data PluginRecompile Source #

Constructors

ForceRecompile
NoForceRecompile
MaybeRecompile Fingerprint

Instances

Instances details

Outputable PluginRecompile Source #
Instance details Defined in GHC.Driver.Plugins Methods ppr :: PluginRecompile -> SDoc Source #
Monoid PluginRecompile Source #
Instance details Defined in GHC.Driver.Plugins Methods mempty :: PluginRecompile # mappend :: PluginRecompile -> PluginRecompile -> PluginRecompile # mconcat :: [PluginRecompile] -> PluginRecompile #
Semigroup PluginRecompile Source #
Instance details Defined in GHC.Driver.Plugins Methods (<>) :: PluginRecompile -> PluginRecompile -> PluginRecompile # sconcat :: NonEmpty PluginRecompile -> PluginRecompile # stimes :: Integral b => b -> PluginRecompile -> PluginRecompile #

Plugin types

Frontend plugins

data FrontendPlugin Source #

Constructors

FrontendPlugin
Fields frontend :: FrontendPluginAction

defaultFrontendPlugin :: FrontendPlugin Source #

type FrontendPluginAction = [String] -> [(String, Maybe Phase)] -> Ghc () Source #

Core plugins

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

type CorePlugin = [CommandLineOption] -> [CoreToDo] -> CoreM [CoreToDo] Source #

Typechecker plugins

Typechecker plugins allow plugins to provide evidence to the typechecker.

type TcPlugin = [CommandLineOption] -> Maybe TcPlugin Source #

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

keepRenamedSource :: [CommandLineOption] -> TcGblEnv -> HsGroup GhcRn -> TcM (TcGblEnv, HsGroup GhcRn) Source #

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.

type DefaultingPlugin = [CommandLineOption] -> Maybe DefaultingPlugin Source #

Hole fit plugins

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

data HoleFitPluginR Source #

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.

type LatePlugin = HscEnv -> [CommandLineOption] -> (CgGuts, CostCentreState) -> IO (CgGuts, CostCentreState) Source #

Internal

data PluginWithArgs Source #

Constructors

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

pluginsWithArgs :: Plugins -> [PluginWithArgs] Source #

pluginRecompile' :: PluginWithArgs -> IO PluginRecompile Source #

data LoadedPlugin Source #

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

Constructors

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

lpModuleName :: LoadedPlugin -> ModuleName Source #

data StaticPlugin Source #

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

Constructors

StaticPlugin
Fields spPlugin :: PluginWithArgs the actual plugin together with its commandline arguments spInitialised :: Bool has this plugin been initialised (i.e. driverPlugin has been run)

data ExternalPlugin Source #

External plugin loaded directly from a library without loading module interfaces

Constructors

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

mapPlugins :: Plugins -> (Plugin -> [CommandLineOption] -> a) -> [a] Source #

withPlugins :: Monad m => Plugins -> PluginOperation m a -> a -> m a Source #

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

withPlugins_ :: Monad m => Plugins -> ConstPluginOperation m a -> a -> m () Source #

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