debug sunflow; avoid duplicate elem in treeset
finish sunflow
merge batik, fix conflicts, need to set boolean for substitute
when check 2 p2sets' equality, first check their sizes
fix a bug of propagating locals because of not considering propagating the parameters as roots of local access paths encoded in the constraints of an local --> alloc edge which we would like not to propagate
nothing, before working on merging fields
add a merge fields option