`std_logic_signed`

This library extends the `std_logic_arith`

library to handle `std_logic_vector`

values as signed integers.
This is a Synopsys extention. The source code is in std_logic_signed.vhd and is freely redistributable.

This library defines all of the same
arithmetic (`+`

, `-`

, `*`

),
comparison (`<`

, `<=`

, `>`

, `>=`

, `=`

, `/=`

) and
shift (`shl`

, `shr`

)
operations as the `std_logic_arith`

library. This difference is that the extensions will take `std_logic_vector`

values as arguments *and treat them as 2's complement signed integers* (ie. just like type `signed`

values).

The function `conv_integer`

is also defined on `std_logic_vector`

and treats the value like a signed integer:

`function conv_integer(arg: std_logic_vector) return integer;`