Apart from a missing module doc comment for `TaintTrackingImpl.qll` which we'll need to synchronize with the other languages (https://github.com/Semmle/ql/pull/3155), this gets us to 100% Qldoc coverage.
We currently use a script to keep certain duplicate QL files in sync across the repo. For historical reasons, this script has lived in the private repo alongside the rest of CodeQL, even though it's only used for files in the public `ql` repo. This PR moves the script into the public `ql` repo. It is still invoked by Jenkins scripts that live in the private repo during CI, but it can also be invoked directly without having a checkout of the private repo. This is useful for anyone who is modifying the dataflow or IR libraries with only a QL checkout.
This PR adds better support for differentiating complex and imaginary floating-point types from real floating-point types, in both the AST and in the IR type system.
*AST Changes*
- Introduces the new class `TypeDomain`, which can be either `RealDomain`, `ImaginaryDomain` or `ComplexDomain`. "type domain" is the term used for this concept in the C standard, and I couldn't think of a better one.
- Introduces `FloatingPointType.getDomain()`, to get the type domain of the type.
- Introduces `FloatingPointType.getBase()`, to get the numeric base of the type (either 2 or 10).
- Introduces three new subtypes of `FloatingPointType`: `RealNumberType`, `ComplexNumberType`, and `ImaginaryNumberType`, which differentiate between the types based on their type domain. Note that the decimal types (e.g., `_Decimal32`) are included in `RealNumberType`.
- Introduces two new subtypes of `FloatingPointType`: `BinaryFloatingPointType` and `DecimalFloatingPointType`, which differentiate between the types based on their numeric base, independent of type domain.
*IR Changes*
- `IRFloatingPointType` now has two additional parameters: the base and the type domain.
- New test that ensures that C++ types get mapped to the correct IR types.
- New IR test that verifies the IR for some basic usage of complex FP types.
With the new `unique` aggregate added to QL, we can express directly
what the "min = max" pattern emulates.
Replacing "min and max" with `unique` might in general lead to fewer
results, but that happens only in cases where the aggregate expression
has multiple values. For the three predicates changed in this commit,
that should only happen on malformed databases.
