[PATCH] D20776: [CFLAA] Teach cfl-aa to understand heap memory allocation

[Jia Chen via llvm-commits]

grievejia added a comment.

In http://reviews.llvm.org/D20776#443810, @george.burgess.iv wrote:

> We treat values that don't exist in StratifiedSets conservatively because the IR can be modified after we run CFLAA on it.


Hmm, this is strange. To me the one and only right thing to do after IR changes is to invalidate the cfl-aa pass and re-run the analysis. In general it is not safe to persist alias analysis result across IR modifications. In your example, what if, instead of adding new GEP to the IR, the points-to set of some existing value gets updated? The analysis result can't be used anyway.


http://reviews.llvm.org/D20776