From 5e545c8f86b9a82c09dba062b2e73e0c0348c10c Mon Sep 17 00:00:00 2001
From: Jakob Rath <git@jakobrath.eu>
Date: Wed, 7 Feb 2024 15:26:15 +0100
Subject: [PATCH] Add merge_level

---
 src/sat/smt/polysat_egraph.cpp | 9 +++++++++
 src/sat/smt/polysat_solver.h   | 1 +
 2 files changed, 10 insertions(+)

diff --git a/src/sat/smt/polysat_egraph.cpp b/src/sat/smt/polysat_egraph.cpp
index 56246c97b..f55d25088 100644
--- a/src/sat/smt/polysat_egraph.cpp
+++ b/src/sat/smt/polysat_egraph.cpp
@@ -23,6 +23,15 @@ Author:
 
 namespace polysat {
 
+    unsigned solver::merge_level(euf::enode* a, euf::enode* b) {
+        sat::literal_vector r;
+        ctx.get_eq_antecedents(a, b, r);
+        unsigned level = 0;
+        for (sat::literal lit : r)
+            level = std::max(level, s().lvl(lit));
+        return level;
+    }
+
     // walk the egraph starting with pvar for suffix overlaps.
     void solver::get_bitvector_suffixes(pvar pv, offset_slices& out) {       
         uint_set seen;
diff --git a/src/sat/smt/polysat_solver.h b/src/sat/smt/polysat_solver.h
index c70a89989..321b807fd 100644
--- a/src/sat/smt/polysat_solver.h
+++ b/src/sat/smt/polysat_solver.h
@@ -111,6 +111,7 @@ namespace polysat {
 
         sat::check_result intblast();
 
+        unsigned merge_level(euf::enode* a, euf::enode* b);
         void explain_slice(pvar v, pvar w, unsigned offset, std::function<void(euf::enode*, euf::enode*)> const& consume);
         void explain_fixed(pvar v, fixed_slice const& s, std::function<void(euf::enode*, euf::enode*)> const& consume_eq);