| Safe Haskell | None |
|---|
Feldspar.Core.Frontend.SizeProp
Description
The functions in this module can be used to help size inference (which, in turn, helps deriving upper bounds of array sizes and helps optimization).
- type SizeCap a = Data a -> Data a
- sizeProp :: (Syntax a, Type b) => (Size (Internal a) -> Size b) -> a -> SizeCap b
- cap :: Type a => Size a -> SizeCap a
- notAbove :: (Type a, Bounded a, Size a ~ Range a) => Data a -> SizeCap a
- notBelow :: (Type a, Bounded a, Size a ~ Range a) => Data a -> SizeCap a
- between :: (Type a, Bounded a, Size a ~ Range a) => Data a -> Data a -> SizeCap a
Documentation
type SizeCap a = Data a -> Data aSource
An identity function affecting the abstract size information used during
optimization. The application of a SizeCap is a guarantee (by the caller)
that the argument is within a certain size (determined by the creator of the
SizeCap, e.g. sizeProp).
Warning: If the guarantee is not fulfilled, optimizations become unsound!
In general, the size of the resulting value is the intersection of the cap
size and the size obtained by ordinary size inference. That is, a SizeCap
can only make the size more precise, not less precise.
sizeProp :: (Syntax a, Type b) => (Size (Internal a) -> Size b) -> a -> SizeCap bSource
sizeProp prop a b: A guarantee that b is within the size (prop sa),
where sa is the size of a.
notAbove :: (Type a, Bounded a, Size a ~ Range a) => Data a -> SizeCap aSource
notAbove a b: A guarantee that b <= a holds