Fix true cycle detection in DFG

src/V3DfgBreakCycles.cpp

@@ -54,7 +54,7 @@ class TraceDriver final : public DfgVisitor {
 
         struct Equal final {
             bool operator()(const Visited& a, const Visited& b) const {
-                return a.m_vtxp == b.m_vtxp && a.m_lsb == b.m_lsb && a.m_msb == b.m_lsb;
+                return a.m_vtxp == b.m_vtxp && a.m_lsb == b.m_lsb && a.m_msb == b.m_msb;
             }
         };
     };

test_regress/t/t_dfg_true_cycle_bad.v

@@ -10,7 +10,7 @@ module t(
     output wire [9:0] o
 );
     assign o[1:0] = o[9:8];
-    assign o[3:2] = {o[0], o[1]};
+    assign o[3:2] = o[1:0];
     assign o[7:4] = 4'(o[3:2]);
     assign o[9:8] = o[5:4];
 endmodule