GHC.Core.Opt.Monad

Configuration of the core-to-core passes

data CoreToDo

Constructors

CoreDoSimplify Int SimplMode

CoreDoPluginPass String CorePluginPass

CoreDoFloatInwards

CoreDoFloatOutwards FloatOutSwitches

CoreLiberateCase

CoreDoPrintCore

CoreDoStaticArgs

CoreDoCallArity

CoreDoExitify

CoreDoDemand

CoreDoCpr

CoreDoWorkerWrapper

CoreDoSpecialising

CoreDoSpecConstr

CoreCSE

CoreDoRuleCheck CompilerPhase String

CoreDoNothing

CoreDoPasses [CoreToDo]

CoreDesugar

CoreDesugarOpt

CoreTidy

CorePrep

CoreAddCallerCcs

CoreAddLateCcs

CoreOccurAnal

Instances

Outputable CoreToDo

Defined in GHC.Core.Opt.Monad

Methods

ppr :: CoreToDo -> SDoc

runWhen :: Bool -> CoreToDo -> CoreToDo

runMaybe :: Maybe a -> (a -> CoreToDo) -> CoreToDo

data SimplMode

Constructors

SimplMode

Fields

• sm_names :: [String]

  Name(s) of the phase

• sm_phase :: CompilerPhase
• sm_uf_opts :: !UnfoldingOpts

  Unfolding options

• sm_rules :: !Bool

  Whether RULES are enabled

• sm_inline :: !Bool

  Whether inlining is enabled

• sm_case_case :: !Bool

  Whether case-of-case is enabled

• sm_eta_expand :: !Bool

  Whether eta-expansion is enabled

• sm_cast_swizzle :: !Bool

  Do we swizzle casts past lambdas?

• sm_pre_inline :: !Bool

  Whether pre-inlining is enabled

• sm_logger :: !Logger
• sm_dflags :: DynFlags

Instances

Outputable SimplMode

Defined in GHC.Core.Opt.Monad

Methods

ppr :: SimplMode -> SDoc

data FloatOutSwitches

Constructors

FloatOutSwitches

Fields

• floatOutLambdas :: Maybe Int

  Just n = float lambdas to top level, if doing so will abstract over n or fewer value variables Nothing = float all lambdas to top level, regardless of how many free variables Just 0 is the vanilla case: float a lambda iff it has no free vars

• floatOutConstants :: Bool

  True = float constants to top level, even if they do not escape a lambda

• floatOutOverSatApps :: Bool

  True = float out over-saturated applications based on arity information. See Note [Floating over-saturated applications] in GHC.Core.Opt.SetLevels

• floatToTopLevelOnly :: Bool

  Allow floating to the top level only.

Instances

Outputable FloatOutSwitches

Defined in GHC.Core.Opt.Monad

Methods

ppr :: FloatOutSwitches -> SDoc

pprPassDetails :: CoreToDo -> SDoc

Plugins

type CorePluginPass = ModGuts -> CoreM ModGuts

A description of the plugin pass itself

bindsOnlyPass :: (CoreProgram -> CoreM CoreProgram) -> ModGuts -> CoreM ModGuts

Counting

data SimplCount

doSimplTick :: DynFlags -> Tick -> SimplCount -> SimplCount

doFreeSimplTick :: Tick -> SimplCount -> SimplCount

simplCountN :: SimplCount -> Int

pprSimplCount :: SimplCount -> SDoc

plusSimplCount :: SimplCount -> SimplCount -> SimplCount

zeroSimplCount :: DynFlags -> SimplCount

isZeroSimplCount :: SimplCount -> Bool

hasDetailedCounts :: SimplCount -> Bool

data Tick

Constructors

PreInlineUnconditionally Id

PostInlineUnconditionally Id

UnfoldingDone Id

RuleFired FastString

LetFloatFromLet

EtaExpansion Id

EtaReduction Id

BetaReduction Id

CaseOfCase Id

KnownBranch Id

CaseMerge Id

AltMerge Id

CaseElim Id

CaseIdentity Id

FillInCaseDefault Id

SimplifierDone

Instances

Outputable Tick

Defined in GHC.Core.Opt.Monad

Methods

ppr :: Tick -> SDoc

Eq Tick

Defined in GHC.Core.Opt.Monad

Methods

(==) :: Tick -> Tick -> Bool

(/=) :: Tick -> Tick -> Bool

Ord Tick

Defined in GHC.Core.Opt.Monad

Methods

compare :: Tick -> Tick -> Ordering

(<) :: Tick -> Tick -> Bool

(<=) :: Tick -> Tick -> Bool

(>) :: Tick -> Tick -> Bool

(>=) :: Tick -> Tick -> Bool

max :: Tick -> Tick -> Tick

min :: Tick -> Tick -> Tick

The monad

data CoreM a

The monad used by Core-to-Core passes to register simplification statistics. Also used to have common state (in the form of UniqueSupply) for generating Uniques.

Instances

MonadIO CoreM

Defined in GHC.Core.Opt.Monad

Methods

liftIO :: IO a -> CoreM a

Alternative CoreM

Defined in GHC.Core.Opt.Monad

Methods

empty :: CoreM a

(<|>) :: CoreM a -> CoreM a -> CoreM a

some :: CoreM a -> CoreM [a]

many :: CoreM a -> CoreM [a]

Applicative CoreM

Defined in GHC.Core.Opt.Monad

Methods

pure :: a -> CoreM a

(<*>) :: CoreM (a -> b) -> CoreM a -> CoreM b

liftA2 :: (a -> b -> c) -> CoreM a -> CoreM b -> CoreM c

(*>) :: CoreM a -> CoreM b -> CoreM b

(<*) :: CoreM a -> CoreM b -> CoreM a

Functor CoreM

Defined in GHC.Core.Opt.Monad

Methods

fmap :: (a -> b) -> CoreM a -> CoreM b

(<$) :: a -> CoreM b -> CoreM a

Monad CoreM

Defined in GHC.Core.Opt.Monad

Methods

(>>=) :: CoreM a -> (a -> CoreM b) -> CoreM b

(>>) :: CoreM a -> CoreM b -> CoreM b

return :: a -> CoreM a

MonadPlus CoreM

Defined in GHC.Core.Opt.Monad

Methods

mzero :: CoreM a

mplus :: CoreM a -> CoreM a -> CoreM a

HasDynFlags CoreM

Defined in GHC.Core.Opt.Monad

Methods

getDynFlags :: CoreM DynFlags

MonadUnique CoreM

Defined in GHC.Core.Opt.Monad

Methods

getUniqueSupplyM :: CoreM UniqSupply

getUniqueM :: CoreM Unique

getUniquesM :: CoreM [Unique]

HasModule CoreM

Defined in GHC.Core.Opt.Monad

Methods

getModule :: CoreM Module

HasLogger CoreM

Defined in GHC.Core.Opt.Monad

Methods

getLogger :: CoreM Logger

runCoreM

Arguments

:: HscEnv

-> RuleBase

-> Char

Mask

-> Module

-> ModuleSet

-> PrintUnqualified

-> SrcSpan

-> CoreM a

-> IO (a, SimplCount)

Reading from the monad

getHscEnv :: CoreM HscEnv

getRuleBase :: CoreM RuleBase

getModule :: HasModule m => m Module

getDynFlags :: HasDynFlags m => m DynFlags

getPackageFamInstEnv :: CoreM PackageFamInstEnv

getVisibleOrphanMods :: CoreM ModuleSet

getUniqMask :: CoreM Char

getPrintUnqualified :: CoreM PrintUnqualified

getSrcSpanM :: CoreM SrcSpan

Writing to the monad

addSimplCount :: SimplCount -> CoreM ()

Lifting into the monad

liftIO :: MonadIO m => IO a -> m a

Lift a computation from the IO monad. This allows us to run IO computations in any monadic stack, so long as it supports these kinds of operations (i.e. IO is the base monad for the stack).

Example

import Control.Monad.Trans.State -- from the "transformers" library

printState :: Show s => StateT s IO ()
printState = do
  state <- get
  liftIO $ print state

Had we omitted liftIO, we would have ended up with this error:

• Couldn't match type ‘IO’ with ‘StateT s IO’
 Expected type: StateT s IO ()
   Actual type: IO ()

The important part here is the mismatch between StateT s IO () and IO ().

Luckily, we know of a function that takes an IO a and returns an (m a): liftIO, enabling us to run the program and see the expected results:

> evalStateT printState "hello"
"hello"

> evalStateT printState 3
3

liftIOWithCount :: IO (SimplCount, a) -> CoreM a

Lift an IO operation into CoreM while consuming its SimplCount

Dealing with annotations

getAnnotations :: Typeable a => ([Word8] -> a) -> ModGuts -> CoreM (ModuleEnv [a], NameEnv [a])

Get all annotations of a given type. This happens lazily, that is no deserialization will take place until the [a] is actually demanded and the [a] can also be empty (the UniqFM is not filtered).

This should be done once at the start of a Core-to-Core pass that uses annotations.

See Note [Annotations]

getFirstAnnotations :: Typeable a => ([Word8] -> a) -> ModGuts -> CoreM (ModuleEnv a, NameEnv a)

Get at most one annotation of a given type per annotatable item.

Screen output

putMsg :: SDoc -> CoreM ()

Output a message to the screen

putMsgS :: String -> CoreM ()

Output a String message to the screen

errorMsg :: SDoc -> CoreM ()

Output an error to the screen. Does not cause the compiler to die.

errorMsgS :: String -> CoreM ()

Output an error to the screen. Does not cause the compiler to die.

msg :: MessageClass -> SDoc -> CoreM ()

fatalErrorMsg :: SDoc -> CoreM ()

Output a fatal error to the screen. Does not cause the compiler to die.

fatalErrorMsgS :: String -> CoreM ()

Output a fatal error to the screen. Does not cause the compiler to die.

debugTraceMsg :: SDoc -> CoreM ()

Outputs a debugging message at verbosity level of -v or higher

debugTraceMsgS :: String -> CoreM ()

Output a string debugging message at verbosity level of -v or higher