resurrect rewriting of equality over ite

Signed-off-by: Nikolaj Bjorner <[email protected]>
Z3Prover · Nov 23, 2024 · 65bfcec · 65bfcec
1 parent 0bf9369
commit 65bfcec
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Showing 2 changed files with 15 additions and 1 deletion.
diff --git a/src/ast/rewriter/arith_rewriter.cpp b/src/ast/rewriter/arith_rewriter.cpp
@@ -740,6 +740,20 @@ br_status arith_rewriter::mk_le_ge_eq_core(expr * arg1, expr * arg2, op_kind kin
         case EQ: result = m.mk_ite(c, m.mk_eq(t, arg2), m.mk_eq(e, arg2)); return BR_REWRITE2;
         }
     }
+    if (m.is_ite(arg2, c, t, e) && is_numeral(t, a2) && is_numeral(arg1, a1)) {
+        switch (kind) {
+        case LE: result = a1 <= a2 ? m.mk_or(c, m_util.mk_le(arg1, e)) : m.mk_and(m.mk_not(c), m_util.mk_le(arg1, e)); return BR_REWRITE2;
+        case GE: result = a1 >= a2 ? m.mk_or(c, m_util.mk_ge(arg1, e)) : m.mk_and(m.mk_not(c), m_util.mk_ge(arg1, e)); return BR_REWRITE2;
+        case EQ: result = a1 == a2 ? m.mk_or(c, m.mk_eq(e, arg1)) : m.mk_and(m.mk_not(c), m_util.mk_eq(e, arg1)); return BR_REWRITE2;
+        }
+    }
+    if (m.is_ite(arg2, c, t, e) && is_numeral(e, a2) && is_numeral(arg1, a1)) {
+        switch (kind) {
+        case LE: result = a1 <= a2 ? m.mk_or(m.mk_not(c), m_util.mk_le(arg1, t)) : m.mk_and(c, m_util.mk_le(arg1, t)); return BR_REWRITE2;
+        case GE: result = a1 >= a2 ? m.mk_or(m.mk_not(c), m_util.mk_ge(arg1, e)) : m.mk_and(c, m_util.mk_ge(arg1, t)); return BR_REWRITE2;
+        case EQ: result = a1 == a2 ? m.mk_or(m.mk_not(c), m.mk_eq(t, arg1)) : m.mk_and(c, m_util.mk_eq(t, arg1)); return BR_REWRITE2;
+        }
+    }
     if (m_util.is_to_int(arg2) && is_numeral(arg1)) {        
         kind = inv(kind);
         std::swap(arg1, arg2);

diff --git a/src/ast/rewriter/th_rewriter.cpp b/src/ast/rewriter/th_rewriter.cpp
@@ -320,7 +320,7 @@ struct th_rewriter_cfg : public default_rewriter_cfg {
                 return pull_ite_core<true>(f, to_app(args[1]), to_app(args[0]), result);
         }
         family_id fid = f->get_family_id();
-        if (num == 2 && (fid == m().get_basic_family_id() || fid == m_bv_rw.get_fid())) {
+        if (num == 2 && (fid == m().get_basic_family_id())) {
             // (f v3 (ite c v1 v2)) --> (ite v (f v3 v1) (f v3 v2))
             if (m().is_value(args[0]) && is_ite_value_tree(args[1])) 
                 return pull_ite_core<true>(f, to_app(args[1]), to_app(args[0]), result);