Do live variable analysis (LVs).
A variable is 'live' at some point if there is a
subsequent use of it before a redefinition.
Binlv = the set of variables live at the beginning of B.
Boutlv = the set of variables live at the end of B.
Bgen = set of variables used before any definition in B.
Bkill = set of variables unambiguously defined before
any use in B.
Note that Bgen & Bkill = 0.
The D Programming Language's Unofficial Docs
beta
Do live variable analysis (LVs). A variable is 'live' at some point if there is a subsequent use of it before a redefinition. Binlv = the set of variables live at the beginning of B. Boutlv = the set of variables live at the end of B. Bgen = set of variables used before any definition in B. Bkill = set of variables unambiguously defined before any use in B. Note that Bgen & Bkill = 0.