[LLVMdev] Incremental SSA update

[Ralf Karrenberg]

Hi,

does LLVM have a mechanism to automatically update SSA form, e.g. after
insertion of additional definitions of a variable? This would
recursively traverse the dominance tree of all uses of the definition
backwards and insert phi-functions where ever they are needed.

http://portal.acm.org/citation.cfm?id=277656&dl=GUIDE, (Paragraph 4.5)
provides an algorithm for such an incremental SSA update which I would
implement if nothing similar(ly efficient) already exists.


By now I have implemented both a Control Dependence Analysis and an
If-Conversion pass. Both passes are not largely tested yet and probably
will not match any desired quality of code.
Yet I would like to contribute them at some point, but I am unsure about
requirements etc. and would appreciate some hints on how to proceed :).

Regards,
Ralf