Comment by gergo_barany

Also, for a different notion of "cruft", informally it seems to me like new SSA-based compilers tend to choose an SSA representation with basic block arguments instead of the traditional phi instructions. There are probably reasons for this! I'm not aware of a Sea of Nodes compiler with (some notion corresponding to) block arguments, but it might be fun to explore this when designing a new compiler from the ground up. Might be too late for TB, though.