mirror of
https://github.com/github/codeql.git
synced 2025-12-23 04:06:37 +01:00
This commit removes SSA nodes from the data flow graph. Specifically, for a definition and use such as ```python x = expr y = x + 2 ``` we used to have flow from `expr` to an SSA variable representing x and from that SSA variable to the use of `x` in the definition of `y`. Now we instead have flow from `expr` to the control flow node for `x` at line 1 and from there to the control flow node for `x` at line 2. Specific changes: - `EssaNode` from the data flow layer no longer exists. - Several glue steps between `EssaNode`s and `CfgNode`s have been deleted. - Entry nodes are now admitted as `CfgNodes` in the data flow layer (they were filtered out before). - Entry nodes now have a new `toString` taking into account that the module name may be ambigous. - Some tests have been rewritten to accomodate the changes, but only `python/ql/test/experimental/dataflow/basic/maximalFlowsConfig.qll` should have semantic changes. - Comments have been updated - Test output has been updated, but apart from `python/ql/test/experimental/dataflow/basic/maximalFlows.expected` only `python/ql/test/experimental/dataflow/typetracking-summaries/summaries.py` should have a semantic change. This is a bonus fix, probably meaning that something was never connected up correctly.
Note that the tests in this directory are very shallow, and simply show that the query is able to produce alerts.
More in-depth tests can be found for the individual frameworks that we have modeled Cryptography::CryptographicOperation for.