CoreOpt

ghc-8.10.1: The GHC API

Safe Haskell | None
Language | Haskell2010

CoreOpt

Contents

- Simple expression optimiser
- Join points
- Predicates on expressions
- Coercions and casts

Synopsis

- simpleOptPgm :: DynFlags -> Module -> CoreProgram -> [CoreRule] -> IO (CoreProgram, [CoreRule])
- simpleOptExpr :: DynFlags -> CoreExpr -> CoreExpr
- simpleOptExprWith :: DynFlags -> Subst -> InExpr -> OutExpr
- joinPointBinding_maybe :: InBndr -> InExpr -> Maybe (InBndr, InExpr)
- joinPointBindings_maybe :: [(InBndr, InExpr)] -> Maybe [(InBndr, InExpr)]
- exprIsConApp_maybe :: InScopeEnv -> CoreExpr -> Maybe (InScopeSet, [FloatBind], DataCon, [Type], [CoreExpr])
- exprIsLiteral_maybe :: InScopeEnv -> CoreExpr -> Maybe Literal
- exprIsLambda_maybe :: InScopeEnv -> CoreExpr -> Maybe (Var, CoreExpr, [Tickish Id])
- pushCoArg :: CoercionR -> CoreArg -> Maybe (CoreArg, MCoercion)
- pushCoValArg :: CoercionR -> Maybe (Coercion, MCoercion)
- pushCoTyArg :: CoercionR -> Type -> Maybe (Type, MCoercionR)
- collectBindersPushingCo :: CoreExpr -> ([Var], CoreExpr)

## Simple expression optimiser

simpleOptPgm :: DynFlags -> Module -> CoreProgram -> [CoreRule] -> IO (CoreProgram, [CoreRule]) Source #

simpleOptExpr :: DynFlags -> CoreExpr -> CoreExpr Source #

simpleOptExprWith :: DynFlags -> Subst -> InExpr -> OutExpr Source #

## Join points

joinPointBinding_maybe :: InBndr -> InExpr -> Maybe (InBndr, InExpr) Source #

Returns Just (bndr,rhs) if the binding is a join point: If it's a JoinId, just return it If it's not yet a JoinId but is always tail-called, make it into a JoinId and return it. In the latter case, eta-expand the RHS if necessary, to make the lambdas explicit, as is required for join points

Precondition: the InBndr has been occurrence-analysed, so its OccInfo is valid

joinPointBindings_maybe :: [(InBndr, InExpr)] -> Maybe [(InBndr, InExpr)] Source #

## Predicates on expressions

exprIsConApp_maybe :: InScopeEnv -> CoreExpr -> Maybe (InScopeSet, [FloatBind], DataCon, [Type], [CoreExpr]) Source #

Returns `Just ([b1..bp], dc, [t1..tk], [x1..xn])` if the argument expression is a *saturated* constructor application of the form `let b1 in .. let bp in dc t1..tk x1 .. xn`, where t1..tk are the *universally-quantified* type args of `dc`. Floats can also be (and most likely are) single-alternative case expressions. Why does `exprIsConApp_maybe` return floats? We may have to look through lets and cases to detect that we are in the presence of a data constructor wrapper. In this case, we need to return the lets and cases that we traversed. See Note [exprIsConApp_maybe on data constructors with wrappers]. Data constructor wrappers are unfolded late, but we really want to trigger case-of-known-constructor as early as possible. See also Note [Activation for data constructor wrappers] in MkId.

We also return the incoming InScopeSet, augmented with the binders from any [FloatBind] that we return

exprIsLiteral_maybe :: InScopeEnv -> CoreExpr -> Maybe Literal Source #

exprIsLambda_maybe :: InScopeEnv -> CoreExpr -> Maybe (Var, CoreExpr, [Tickish Id]) Source #

## Coercions and casts

pushCoArg :: CoercionR -> CoreArg -> Maybe (CoreArg, MCoercion) Source #

pushCoValArg :: CoercionR -> Maybe (Coercion, MCoercion) Source #

pushCoTyArg :: CoercionR -> Type -> Maybe (Type, MCoercionR) Source #

collectBindersPushingCo :: CoreExpr -> ([Var], CoreExpr) Source #