CLaSH.Class.Resize

Documentation

class Resize f where

Coerce a value to be represented by a different number of bits

Minimal complete definition

resize, zeroExtend, signExtend, truncateB

Methods

resize :: (KnownNat a, KnownNat b) => f a -> f b

A sign-preserving resize operation

• For signed datatypes: Increasing the size of the number replicates the sign bit to the left. Truncating a number to length L keeps the sign bit and the rightmost L-1 bits.
• For unsigned datatypes: Increasing the size of the number extends with zeros to the left. Truncating a number of length N to a length L just removes the left (most significant) N-L bits.

extend :: (KnownNat a, KnownNat (b + a)) => f a -> f (b + a)

Perform a zeroExtend for unsigned datatypes, and signExtend for a signed datatypes

zeroExtend :: (KnownNat a, KnownNat b, KnownNat (b + a)) => f a -> f (b + a)

Add extra zero bits in front of the MSB

signExtend :: (KnownNat a, KnownNat (b + a)) => f a -> f (b + a)

Add extra sign bits in front of the MSB

truncateB :: KnownNat a => f (b + a) -> f a

Remove bits from the MSB

Instances

Resize BitVector

Resize Signed

Resize Unsigned