mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-05-06 15:25:46 +00:00
Code Activity

comments

Browse source 
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2021-09-11 16:55:49 +02:00
parent d514464e30
commit f8a3857adb
7 changed files with 61 additions and 40 deletions
Download patch file Download diff file Expand all files Collapse all files

17
src/math/polysat/saturation.cpp
View file

@ -12,21 +12,16 @@ Author:
TODO: preserve falsification
- each rule selects a certain premise that is problematic,
We assume that problematic premises are false in the current assignment
The derived consequence should also be false in the current assignment to be effective, but simpler so that we can resolve.
- each rule selects a certain premises that are problematic.
If the problematic premise is false under the current assignment, the newly inferred
literal should also be false in the assignment in order to preserve conflicts.
TODO:
- remove level information from created constraints.
TODO: when we check that 'x' is "unary":
- in principle, 'x' could be any polynomial. However, we need to divide the lhs by x, and we don't have general polynomial division yet.
so for now we just allow the form 'value*variable'.
(extension to arbitrary monomials for 'x' should be fairly easy too)
TODO:
- remove the "problematic" literal from the core itself such that reference counts on variable assignments are decreased.
--*/
#include "math/polysat/saturation.h"
#include "math/polysat/solver.h"
@ -63,11 +58,11 @@ namespace polysat {
* The lemmas outlines in the rules are valid and therefore c is implied.
*/
bool inf_saturate::propagate(conflict_core& core, inequality const& crit, signed_constraint& c, clause_builder& reason) {
if (c.is_currently_true(s()))
if (crit.as_signed_constraint().is_currently_false(s()) && c.is_currently_true(s()))
return false;
core.insert(c);
reason.push(c);
// TODO core.erase(crit.as_signed_constraint());
core.remove(crit.as_signed_constraint());
s().propagate_bool(c.blit(), reason.build().get());
return true;
}
@ -265,7 +260,7 @@ namespace polysat {
clause_builder reason(s());
if (!c.is_strict)
reason.push(cm().eq(x - x.manager().mk_val(rational(0))));
reason.push(cm().eq(x));
reason.push(~c.as_signed_constraint());
push_omega(reason, x, y);
return propagate(core, c, c.is_strict, y, z, reason);