Typical implementations of Lengauer-Tarjan are often taken verbatim from Andrew Appel's book and involve higher constant factors than alternative algorithms - such as Cooper et al's "engineered" version of the usual fixpoint algorithm, which is very neat, simple, and performs well.
If you are saying that constructing SSA following the classical approach is a premature optimisation, perhaps you would prefer Braun et al's retelling of Cliff Click's SSA construction algorithm - which works backwards from uses to place phis and requires no dominance information to be computed.
If you are saying that constructing SSA following the classical approach is a premature optimisation, perhaps you would prefer Braun et al's retelling of Cliff Click's SSA construction algorithm - which works backwards from uses to place phis and requires no dominance information to be computed.