diff --git a/kernel/rtlil.h b/kernel/rtlil.h
index 74ded6a55..cf146f786 100644
--- a/kernel/rtlil.h
+++ b/kernel/rtlil.h
@@ -2119,6 +2119,7 @@ public:
 	pool<RTLIL::Cell *> pending_deleted_cells;
 	dict<RTLIL::Wire *, pool<RTLIL::Cell *>> buf_norm_connect_index;
 	void bufNormalize();
+	void dump_sigmap();
 
 protected:
 	SigNormIndex *sig_norm_index = nullptr;
diff --git a/kernel/rtlil_bufnorm.cc b/kernel/rtlil_bufnorm.cc
index 78f99731f..182e159b2 100644
--- a/kernel/rtlil_bufnorm.cc
+++ b/kernel/rtlil_bufnorm.cc
@@ -55,6 +55,19 @@ struct RTLIL::SigNormIndex
 		setup_fanout();
 	}
 
+	void dump_sigmap() {
+		for (auto [name, wire] : module->wires_) { 
+			log_debug("wire %s %p %s\n", name, wire, wire->name);
+			SigSpec ss(wire);
+			log_debug("ss %s\n", log_signal(ss));
+			sigmap(ss);
+			log_debug("sigmapped %s\n", log_signal(ss));
+		}
+		for (auto [lhs, rhs] : module->connections_) {
+			log_debug("connection %s %s\n", log_signal(lhs), log_signal(rhs));
+		}
+	}
+
 	void normalize() {
 		flush_connections();
 		flush_newly_driven();
@@ -346,6 +359,12 @@ void RTLIL::Module::sigNormalize()
 
 }
 
+void RTLIL::Module::dump_sigmap()
+{
+	if (sig_norm_index != nullptr)
+		sig_norm_index->dump_sigmap();
+}
+
 void RTLIL::Module::clear_sig_norm_index()
 {
 	if (sig_norm_index == nullptr)