cxxrtl: treat internal wires used only for debug as constants.

Fixes #2739 (again).
YosysHQ · Jul 17, 2021 · 4aa65f4 · 4aa65f4
1 parent 2db4137
commit 4aa65f4
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/backends/cxxrtl/cxxrtl_backend.cc b/backends/cxxrtl/cxxrtl_backend.cc
@@ -2881,6 +2881,12 @@ struct CxxrtlWorker {
 						debug_live_nodes.erase(node);
 					} else if (wire_type.is_local()) {
 						debug_wire_type = {WireType::LOCAL}; // wire not inlinable
+					} else if (wire_type.type == WireType::UNUSED) {
+						if (wire_init.count(wire)) {
+							debug_wire_type = {WireType::CONST, wire_init.at(wire)};
+						} else {
+							debug_wire_type = {WireType::CONST, RTLIL::SigSpec(RTLIL::S0, wire->width)};
+						} // wire never modified
 					} else {
 						log_assert(wire_type.is_member());
 						debug_wire_type = wire_type; // wire is a member