Make output port a non chain user

diff --git a/passes/techmap/shregmap.cc b/passes/techmap/shregmap.cc
index d95cadde5d30f272e8535e652d8bdd96f3aebe97..3b3170e0491829331273e3db943fbbde21d46285 100644 (file)
--- a/passes/techmap/shregmap.cc
+++ b/passes/techmap/shregmap.cc
@@ -118,7 +118,7 @@ struct ShregmapTechXilinx7 : ShregmapTech
                auto it = sigbit_to_shiftx_offset.find(bit);
                if (it == sigbit_to_shiftx_offset.end())
                        return;
-               if (cell->type == "$shiftx" && port == "\\A")
+               if (cell && cell->type == "$shiftx" && port == "\\A")
                        return;
                sigbit_to_shiftx_offset.erase(it);
        }
@@ -228,8 +228,10 @@ struct ShregmapWorker
        for (auto wire : module->wires())
        {
            if (wire->port_output || wire->get_bool_attribute("\\keep")) {
-               for (auto bit : sigmap(wire))
+               for (auto bit : sigmap(wire)) {
                    sigbit_with_non_chain_users.insert(bit);
+                   if (opts.tech) opts.tech->non_chain_user(bit, nullptr, {});
+               }
            }
 
            if (wire->attributes.count("\\init")) {