"Virtual USE", a tree SSA construct that is part of the alias infrastructure.
Basically a VUSE is a factored USE-DEF chain for memory operands. In Tree-SSA, temporaries that do not have to live in memory are explicitly rewritten in SSA form using SSA_NAME versioning. For temporaries that must live in memory, as well as all other constructs that reside in memory, a factored web of VUSEs, VDEFs, and V_MUST_DEFs is used.
If a variable may have aliases at some point in the program, and one of them is used, a VUSE indicates that this may also be a use of the aliases of that variable.