After publishing Linear scan register allocation on SSA, I had a nice call with Waleed Khan where he showed me how to Datalog. He thought it might be useful to try implementing liveness analysis as a Datalog problem. We started off with the Wimmer2010 CFG example from that post, sketching out manually which variables were live out of each block: R10 out of B1, R12 out of B2, etc. The graph from Wimmer2010 has come back! Remember, we’re using block arguments instead of phis, so B1(R10, R11) ...
