The INT32 API contains the type int32, a vector type
simple-int32-vector and accessor, functions to convert int32 to and from integer, some constant int32 values, and a full range of operators for mod 2^32 arithmetic.
You can find all these by evaluating
(apropos "INT32" "SYSTEM" t)
For details for each, see the entries starting with int32 in The SYSTEM Package.
LispWorks User Guide and Reference Manual - 21 Dec 2011