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add option to propagation quotients

for equations x*y + z = 0,
with x, y, z integer, enforce that x divides z
It is (currently) enabled within Grobner completion
and applied partially to x a variable, z linear, and
only when |z| < |x|.
This commit is contained in:
Nikolaj Bjorner 2025-08-31 14:41:23 -07:00
parent 91b4873b79
commit e91e432496
10 changed files with 516 additions and 258 deletions

View file

@ -269,6 +269,7 @@ class theory_lra::imp {
return ctx().is_relevant(th.get_enode(u));
};
m_nla->set_relevant(is_relevant);
m_nla->updt_params(ctx().get_params());
}
}
@ -1286,23 +1287,24 @@ public:
}
else {
expr_ref abs_q(m.mk_ite(a.mk_ge(q, zero), q, a.mk_uminus(q)), m);
expr_ref mone(a.mk_int(-1), m);
expr_ref modmq(a.mk_sub(mod, abs_q), m);
literal eqz = mk_literal(m.mk_eq(q, zero));
literal mod_ge_0 = mk_literal(a.mk_ge(mod, zero));
literal mod_lt_q = mk_literal(a.mk_le(modmq, mone));
// q = 0 or p = (p mod q) + q * (p div q)
// q = 0 or (p mod q) >= 0
// q = 0 or (p mod q) < abs(q)
// q >= 0 or (p mod q) = (p mod -q)
// q >= 0 or (p mod q) + q <= -1
// q <= 0 or (p mod q) - q <= -1
// (p mod q) = (p mod -q)
mk_axiom(eqz, eq);
mk_axiom(eqz, mod_ge_0);
mk_axiom(eqz, mod_lt_q);
if (!a.is_uminus(q))
mk_axiom(mk_literal(m.mk_eq(mod, a.mk_mod(p, a.mk_uminus(q)))));
mk_axiom(mk_literal(a.mk_le(q, zero)), mk_literal(a.mk_le(a.mk_add(mod, a.mk_mul(mone, q)), mone)));
mk_axiom(mk_literal(a.mk_ge(q, zero)), mk_literal(a.mk_le(a.mk_add(mod, q), mone)));
expr* x = nullptr, * y = nullptr;
if (false && !(a.is_mul(q, x, y) && mone == x))
mk_axiom(mk_literal(m.mk_eq(mod, a.mk_mod(p, a.mk_mul(mone, q)))));
m_arith_eq_adapter.mk_axioms(th.ensure_enode(mod_r), th.ensure_enode(p));
@ -1658,6 +1660,9 @@ public:
return FC_CONTINUE;
}
if (st == FC_GIVEUP)
IF_VERBOSE(0, display(verbose_stream()));
if (!int_undef && !check_bv_terms())
return FC_CONTINUE;