Copyright | (c) 2020 Andrew Lelechenko (c) 2020 Composewell Technologies |
---|---|
License | BSD-3-Clause |
Maintainer | streamly@composewell.com |
Stability | experimental |
Portability | GHC |
Safe Haskell | Safe-Inferred |
Language | Haskell2010 |
Fast, static bitmap lookup utilities
Synopsis
- lookupBit64 :: Addr# -> Int -> Bool
- lookupIntN :: Addr# -> Int -> Int
Documentation
lookupBit64 :: Addr# -> Int -> Bool Source #
lookup64 addr index
looks up the bit stored at bit index index
using a
bitmap starting at the address addr
. Looks up the 64-bit word containing
the bit and then the bit in that word. The caller must make sure that the
64-bit word at the byte address (addr + index / 64) * 8 is legally
accessible memory.