Added preprocessing pass that propagates unconstrained values - solves all of

the unconstrained examples in QF_AUFBV/brummayerbiere3 - should also help
generally on at least BV and maybe others.
Off by default for now - results are mixed and it's hard to evaluate with so
many existing assertion failures and segfaults - will re-evaluate once those
are fixed

1 files changed, 6 insertions, 0 deletions

diff --git a/src/theory/bv/theory_bv_rewrite_rules_normalization.h b/src/theory/bv/theory_bv_rewrite_rules_normalization.h
index 5be052947..197134b6a 100644
--- a/src/theory/bv/theory_bv_rewrite_rules_normalization.h
+++ b/src/theory/bv/theory_bv_rewrite_rules_normalization.h
@@ -405,6 +405,9 @@ Node RewriteRule<SolveEq>::apply(TNode node) {
       updateCoefMap(left[i], size, leftMap, leftConst);
     }
   }
+  else if (left.getKind() == kind::BITVECTOR_NOT && left[0] == right) {
+    return utils::mkFalse();
+  }
   else {
     updateCoefMap(left, size, leftMap, leftConst);
   }
@@ -415,6 +418,9 @@ Node RewriteRule<SolveEq>::apply(TNode node) {
       updateCoefMap(right[i], size, rightMap, rightConst);
     }
   }
+  else if (right.getKind() == kind::BITVECTOR_NOT && right[0] == left) {
+    return utils::mkFalse();
+  }
   else {
     updateCoefMap(right, size, rightMap, rightConst);
   }