--- /dev/null
+/*
+ * yosys -- Yosys Open SYnthesis Suite
+ *
+ * Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct EquivAddPass : public Pass {
+ EquivAddPass() : Pass("equiv_add", "add a $equiv cell") { }
+ virtual void help()
+ {
+ // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+ log("\n");
+ log(" equiv_add gold_sig gate_sig\n");
+ log("\n");
+ log("This command adds an $equiv cell for the specified signals.\n");
+ log("\n");
+ }
+ virtual void execute(std::vector<std::string> args, Design *design)
+ {
+ if (GetSize(args) != 3)
+ cmd_error(args, GetSize(args)-1, "Invalid number of arguments.");
+
+ if (design->selected_active_module.empty())
+ log_cmd_error("This command must be executed in module context!\n");
+
+ Module *module = design->module(design->selected_active_module);
+ log_assert(module != nullptr);
+
+ SigSpec gold_signal, gate_signal;
+
+ if (!SigSpec::parse(gate_signal, module, args[2]))
+ log_cmd_error("Error in gate signal: %s\n", args[2].c_str());
+
+ if (!SigSpec::parse_rhs(gate_signal, gold_signal, module, args[1]))
+ log_cmd_error("Error in gold signal: %s\n", args[1].c_str());
+
+ log_assert(GetSize(gold_signal) == GetSize(gate_signal));
+ SigSpec equiv_signal = module->addWire(NEW_ID, GetSize(gold_signal));
+
+ SigMap sigmap(module);
+ sigmap.apply(gold_signal);
+ sigmap.apply(gate_signal);
+
+ dict<SigBit, SigBit> to_equiv_bits;
+ pool<Cell*> added_equiv_cells;
+
+ for (int i = 0; i < GetSize(gold_signal); i++) {
+ Cell *equiv_cell = module->addEquiv(NEW_ID, gold_signal[i], gate_signal[i], equiv_signal[i]);
+ equiv_cell->set_bool_attribute("\\keep");
+ to_equiv_bits[gold_signal[i]] = equiv_signal[i];
+ to_equiv_bits[gate_signal[i]] = equiv_signal[i];
+ added_equiv_cells.insert(equiv_cell);
+ }
+
+ for (auto cell : module->cells())
+ for (auto conn : cell->connections())
+ if (!added_equiv_cells.count(cell) && cell->input(conn.first)) {
+ SigSpec new_sig;
+ for (auto bit : conn.second)
+ if (to_equiv_bits.count(sigmap(bit)))
+ new_sig.append(to_equiv_bits.at(sigmap(bit)));
+ else
+ new_sig.append(bit);
+ if (conn.second != new_sig)
+ cell->setPort(conn.first, new_sig);
+ }
+ }
+} EquivAddPass;
+
+PRIVATE_NAMESPACE_END