CodeQL library for C#
codeql/csharp-all 0.5.1 (changelog, source)

Member predicate Ssa::PhiNode::hasLastInputRef

Holds if if def is an input to this phi node, and a reference to def at index i in basic block bb can reach this phi node without going through other references.

predicate hasLastInputRef(Definition def, BasicBlock bb, int i)