This patch improves support for local identifiers by explicitly storing representations of their values as divisions of an affine expression by a constant denominator, when such a representation is known.
Exact re-computation of division representations from inequalities is expensive. Many operations on PresburgerSets when local identifiers are involved require these representations. Storing these representations allows for faster computation in PresburgerSet operations where local identifiers are involved.
You can initialize this directly in the member initializer list above right?