Bit::ShiftReg is a perl module that implements rotate left, rotate right,
arithmetic shift left, and logical shift right operations with carry flag for
all C integer types. The results depend on the number of bits with that the
integer types unsigned char, unsigned short, unsigned int, and unsigned long
have on your machine. The module automatically determines the number of bits of
each integer type and adjusts its internal constants accordingly.

WWW: http://search.cpan.org/dist/Bit-ShiftReg/