Improve join-order in pathStep predicate.
Improve join-order in pathStep predicate.

See https://github.com/Semmle/ql/pull/2872.

github/codeql-go,github/codeql-go,github/codeql,github/codeql,github/codeql,github/codeql,github/codeql,github/codeql,github/codeql,github/codeql,github/codeql-go,github/codeql,github/codeql,github/codeql-go,github/codeql,github/codeql,github/codeql,github/codeql,github/codeql