This PR adds short-circuit support to bv_decide to accelerate
multiplications with shared coefficients. In particular, `a * x = b * x`
can be extended to `a = b v (a * x = b * x)`. The latter is faster if `a
= b` is true, as `a = b` may be evaluated without considering the
multiplication circuit. On the other hand, we require the multiplication
circuit, as `a * x = b * x -> a = b` is not always true due to two's
complement wrapping.
We support multiplications through acNF, which takes into account shared
terms across equality canonicalizing `a * (b * c1) = a * (b * c2)` to
`(a * b) * c1 = (a * b) * c2`. As a result, the non-shared terms are
lifted to the top such that canonical rewrites for binary multiplication
with shared terms on the left/right are sufficient.
We add an option `bv_decide +shortCircuit` which controls this feature
(currently disabled by default).
---------
Co-authored-by: Siddharth Bhat <siddu.druid@gmail.com>
Co-authored-by: Henrik Böving <hargonix@gmail.com>
This PR changes `bv_decide`'s configuration from lots of `set_option` to
an elaborated config like `simp` or `omega`. The notable exception is
`sat.solver` which is still a `set_option` such that users can configure
a custom SAT solver globally for an entire project or file. Additionally
it introduces the ability to set `maxSteps` for the simp preprocessing
run through the new config.
The latter feature was requested by people using `bv_decide` on SMTLIB
which has ginormous terms that exceed the default.
Using the same strategy as #5852 this provides `bv_decide` support for
`Bool` and `BitVec` ifs
this in turn instantly enables support for:
- `sdiv`
- `smod`
- `abs`
and thus closes our last discrepancies to QF_BV!
... while at it also call `trivial` to close goals that can be trivially
closed.
---------
Co-authored-by: Siddharth <siddu.druid@gmail.com>
Co-authored-by: Henrik Böving <hargonix@gmail.com>