| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Language.Syntactic.Constructs.Binding.Optimize
Description
Basic optimization
Synopsis
- type ConstFolder dom = forall a. ASTF dom a -> a -> ASTF dom a
- class Optimize sym where
- type Optimize' dom = (Optimize dom, EvalBind dom, AlphaEq dom dom dom [(VarId, VarId)], ConstrainedBy dom Typeable)
- optimizeM :: Optimize' dom => ConstFolder dom -> ASTF dom a -> Writer (Set VarId) (ASTF dom a)
- optimize :: Optimize' dom => ConstFolder dom -> ASTF dom a -> ASTF dom a
- optimizeSymDefault :: Optimize' dom => ConstFolder dom -> (sym sig -> AST dom sig) -> sym sig -> Args (AST dom) sig -> Writer (Set VarId) (ASTF dom (DenResult sig))
Documentation
type ConstFolder dom = forall a. ASTF dom a -> a -> ASTF dom a Source #
Constant folder
Given an expression and the statically known value of that expression,
returns a (possibly) new expression with the same meaning as the original.
Typically, the result will be a Literal, if the relevant type constraints
are satisfied.
class Optimize sym where Source #
Basic optimization
Methods
optimizeSym :: Optimize' dom => ConstFolder dom -> (sym sig -> AST dom sig) -> sym sig -> Args (AST dom) sig -> Writer (Set VarId) (ASTF dom (DenResult sig)) Source #
Bottom-up optimization of an expression. The optimization performed is
up to each instance, but the intention is to provide a sensible set of
"always-appropriate" optimizations. The default implementation
optimizeSymDefault does only constant folding. This constant folding
uses the set of free variables to know when it's static evaluation is
possible. Thus it is possible to help constant folding of other
constructs by pruning away parts of the syntax tree that are known not to
be needed. For example, by replacing (using ordinary Haskell as an
example)
if True then a else b
with a, we don't need to report the free variables in b. This, in
turn, can lead to more constant folding higher up in the expression.
Instances
type Optimize' dom = (Optimize dom, EvalBind dom, AlphaEq dom dom dom [(VarId, VarId)], ConstrainedBy dom Typeable) Source #
optimizeM :: Optimize' dom => ConstFolder dom -> ASTF dom a -> Writer (Set VarId) (ASTF dom a) Source #
optimize :: Optimize' dom => ConstFolder dom -> ASTF dom a -> ASTF dom a Source #
Optimize an expression
optimizeSymDefault :: Optimize' dom => ConstFolder dom -> (sym sig -> AST dom sig) -> sym sig -> Args (AST dom) sig -> Writer (Set VarId) (ASTF dom (DenResult sig)) Source #
Convenient default implementation of optimizeSym (uses evalBind to
partially evaluate)