Pinpoint: Fast and Precise Sparse Value Flow Analysis for Million Lines of Code

Abstract

When dealing with millions of lines of code, we still cannot have the cake and eat it: sparse value-flow analysis is powerful in checking source-sink problems, but existing work cannot escape from the “pointer trap” – a precise points-to analysis limits its scalability and an imprecise one seriously undermines its precision. We present Pinpoint, a holistic approach that decomposes the cost of high-precision points-to analysis by precisely discovering local data dependence and delaying the expensive inter-procedural analysis through memorization. Such memorization enables the on-demand slicing of only the necessary inter-procedural data dependence and path feasibility queries, which are then solved by a costly SMT solver. Experiments show that Pinpoint can check programs such as MySQL (around 2 million lines of code) within 1.5 hours. The overall false positive rate is also very low (14.3% - 23.6%). Pinpoint has discovered over forty real bugs in mature and extensively checked open source systems. And the implementation of Pinpoint and all experimental results are freely available.