Summary:
Change Arith.map to not descend through non-interpreted arithmetic
operators. For example, in `2×(x × y) + 3×z + 4`, `map ~f` will apply
`f` to the subterms `x × y` and `z`, but not `x` or `y`.
The logical notion of "subterm" that is needed by the solver does not
coincide with the representation. This is essentially due to not
"flattening" or "purifying" terms. That is, traditionally `x × y`
would not be permitted as an indeterminate of a polynomial. Instead, a
new variable would need to be introduced: `v = x × y` and then the
polynomial would be expressed as `2×v + 3×z + 4`. Taking maximal
non-interpreted subterms as the definition of "subterm" results in
subterms in the non-flattened representation that are equivalent to
those that would result from flattening the representation.
Reviewed By: jvillard
Differential Revision: D24746235
fbshipit-source-id: d8fcf46a1
Summary:
The implementation of Arithmetic relies on the partial projection from
terms to polynomials. This diff enables it to also embed polynomials
back into terms.
Reviewed By: jvillard
Differential Revision: D24746223
fbshipit-source-id: b6010e7b7
Summary:
Add a distinction between interpreted and uninterpreted arithmetic
terms, and use it in Context.classify. This enables correctly
classifying non-linear terms such as `x × y` as uninterpreted.
Reviewed By: ngorogiannis
Differential Revision: D24746228
fbshipit-source-id: 1a4b0e3bd
Summary:
In the process of computing `Context.solve`, fresh variables can be
generated. Not all of these end up in the final solution
substitution. Currently all of the freshly generated variables are
returned to the client, which leads to extraneous existentials. This
diff trims the returned fresh variables to only those that appear in
the final solution.
Reviewed By: ngorogiannis
Differential Revision: D24746241
fbshipit-source-id: 59a2f221b
Summary:
When exceptions are used due to the lack of goto, use `raise_notrace`
instead of `raise` to avoid the overhead of populating the backtrace.
Reviewed By: ngorogiannis
Differential Revision: D24630525
fbshipit-source-id: c5051d9c4