[k4st]

The Pizlo special approach sounds a bit like converting out of SSA form via compensating `alloca`s in LLVM. E.g. one `alloca` per SSA variable, with a `store` into the `alloca` in the source block, and the `phi` replaced by a `load`.

If this is the case, this is an approach I've taken in the past to unify how LLVM-based taint tracking instrumentation of "normal" `alloca`s and phi nodes works, e.g.: https://github.com/lifting-bits/vmill/blob/master/tools/Tain...

[pizlonator]

It's not, because the Phi's in Pizlo form introduce a Static Single Use variable, which makes them easy to analyze.

Allocas have no requirement that there's a static single use. They are quite hard to analyze.