Copyright	(c) Bryan O'Sullivan 2009
License	BSD-style
Maintainer	bos@serpentine.com
Stability	experimental
Portability	GHC
Safe Haskell	None
Language	Haskell98

Data.Text.Internal.Unsafe.Shift

Description

Warning: this is an internal module, and does not have a stable API or name. Functions in this module may not check or enforce preconditions expected by public modules. Use at your own risk!

Fast, unchecked bit shifting functions.

Synopsis

class UnsafeShift a where
- shiftL :: a -> Int -> a
- shiftR :: a -> Int -> a

Documentation

class UnsafeShift a where Source #

This is a workaround for poor optimisation in GHC 6.8.2. It fails to notice constant-width shifts, and adds a test and branch to every shift. This imposes about a 10% performance hit.

These functions are undefined when the amount being shifted by is greater than the size in bits of a machine Int#.

Methods

shiftL :: a -> Int -> a Source #

shiftR :: a -> Int -> a Source #

Instances

Instances details

UnsafeShift Int Source #
Instance details Defined in Data.Text.Internal.Unsafe.Shift Methods shiftL :: Int -> Int -> Int Source # shiftR :: Int -> Int -> Int Source #
UnsafeShift Word16 Source #
Instance details Defined in Data.Text.Internal.Unsafe.Shift Methods shiftL :: Word16 -> Int -> Word16 Source # shiftR :: Word16 -> Int -> Word16 Source #
UnsafeShift Word32 Source #
Instance details Defined in Data.Text.Internal.Unsafe.Shift Methods shiftL :: Word32 -> Int -> Word32 Source # shiftR :: Word32 -> Int -> Word32 Source #
UnsafeShift Word64 Source #
Instance details Defined in Data.Text.Internal.Unsafe.Shift Methods shiftL :: Word64 -> Int -> Word64 Source # shiftR :: Word64 -> Int -> Word64 Source #