a9984e9d8b
This change gives a slight performance improvement and makes the QL code shorter. It introduces some magic numbers in the code, but those are confined to the `Pos` and `Spec` classes. We get a speed-up because the evaluator has built-in support for integer literals in the `OUTPUT` of `JOIN` operations, whereas `newtype`s have to be explicitly joined on. As a result, a predicate like `CFG::straightLineSparse#ffff` drops from 262 pipeline nodes to 242. I measured performance on https://github.com/jluttine/suitesparse, which is one of the projects that had the biggest slowdown when enabling the QL CFG on lgtm.com. I took two measurements before this change and two after. The `CFG.qll` stage took 117s and 112s before, and it took 106s and 107s after.
Semmle QL
This open source repository contains the standard QL libraries and queries that power LGTM, and the other products that Semmle makes available to its customers worldwide.
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License
The QL queries in this repository are licensed under Apache License 2.0 by Semmle.