Safe Haskell	None
Language	GHC2024

GHC.Core.Opt.Range

Description

Range analysis

See Note [Value range analysis]

Synopsis

data Comparison
- = Gt
- | Ge
- | Lt
- | Le
data Range = MkRange !(Maybe Integer) !(Maybe Integer)
noRange :: Range
valueRange :: Platform -> CoreExpr -> Range
rangeIntersect :: Range -> Range -> Range
rangeCastFrom :: Range -> Range -> Range
inRange :: Integer -> Range -> Bool
rangeSize :: Range -> Maybe Integer
rangeCmp :: Comparison -> Range -> Range -> Maybe Bool
rangeLe :: Range -> Range -> Maybe Bool
rangeGe :: Range -> Range -> Maybe Bool
rangeLt :: Range -> Range -> Maybe Bool
rangeGt :: Range -> Range -> Maybe Bool
rangeOf :: (Bounded a, Integral a) => Range
rangeWord :: Platform -> Range
rangeWord8 :: Range
rangeWord16 :: Range
rangeWord32 :: Range
rangeWord64 :: Range
rangeChar :: Platform -> Range
rangeInt :: Platform -> Range
rangeInt8 :: Range
rangeInt16 :: Range
rangeInt32 :: Range
rangeInt64 :: Range

Documentation

data Comparison Source #

Constructors

Gt
Ge
Lt
Le

Instances

Instances details

Show Comparison Source #
Instance details Defined in GHC.Core.Opt.Range Methods showsPrec :: Int -> Comparison -> ShowS Source # show :: Comparison -> String Source # showList :: [Comparison] -> ShowS Source #

data Range Source #

A range (minBound,maxBound)

Bounds may not be known.

Constructors

MkRange
Fields !(Maybe Integer) Lower bound: Nothing means unbounded below !(Maybe Integer) Upper bound: Nothing means unbounded above

Instances

Instances details

Eq Range Source #
Instance details Defined in GHC.Core.Opt.Range Methods (==) :: Range -> Range -> Bool Source # (/=) :: Range -> Range -> Bool Source #
Show Range Source #
Instance details Defined in GHC.Core.Opt.Range Methods showsPrec :: Int -> Range -> ShowS Source # show :: Range -> String Source # showList :: [Range] -> ShowS Source #

noRange :: Range Source #

valueRange :: Platform -> CoreExpr -> Range Source #

Return the Integer range of an expression

rangeIntersect :: Range -> Range -> Range Source #

Compute the intersection of two overlapping ranges.

If the two ranges don't overlap, result is undefined.

rangeCastFrom :: Range -> Range -> Range Source #

Used for casts that share representation over a sub-range (e.g. [0,127] for Word8# ([0,255]) and Int8# ([-128,127]))

If from_range isn't fully included into to_range, then we return to_range. That's because for now we don't have a way to track disjoined ranges. E.g. if we wanted to cast -1,10 into 0,255, we would need to represent a range union: [0,10] U 255,255

We also use this function to ensure that the result of an arithmetic operation on ranges didn't overflow/underflow.

inRange :: Integer -> Range -> Bool Source #

rangeSize :: Range -> Maybe Integer Source #

rangeCmp :: Comparison -> Range -> Range -> Maybe Bool Source #

Compare two ranges

See Note [Value range analysis]

rangeLe :: Range -> Range -> Maybe Bool Source #

rangeGe :: Range -> Range -> Maybe Bool Source #

rangeLt :: Range -> Range -> Maybe Bool Source #

rangeGt :: Range -> Range -> Maybe Bool Source #

rangeOf :: (Bounded a, Integral a) => Range Source #

rangeWord :: Platform -> Range Source #