JS: fix context sensitivity bug in store-load matching #8478
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Background:
reachableFromStoreBaseforward-tracks the base object of a store whose RHS is potentially reachable. If the RHS of that store is only reachable with call steps, we do not permit the base object to be tracked out of a return edge, as it would lead to wasted work (i.e. we want to prune infeasible flows early).However, it turns out we tried to used the same
callbit for two different purposes:This PR adds a new
booleanparameter to track (1), while the boolean in thePathSummarycorresponds to (2).Evaluation looks ok. The new results are uninteresting and most likely FPs, although it's hard to triage. I've confirmed that the flow steps enabled by this PR are correct in isolation, but the final path contain some spurious flow caused by imprecise handling of array indices and captured variables.