Use only module->addCell() and module->remove() to create and delete cells

30 files changed, 171 insertions, 465 deletions

diff --git a/passes/abc/abc.cc b/passes/abc/abc.cc
index d25f88c0d..980e69aa2 100644
--- a/passes/abc/abc.cc
+++ b/passes/abc/abc.cc
@@ -127,8 +127,7 @@ static void extract_cell(RTLIL::Cell *cell, bool keepff)
 
 		map_signal(sig_q, 'f', map_signal(sig_d));
 
-		module->cells.erase(cell->name);
-		delete cell;
+		module->remove(cell);
 		return;
 	}
 
@@ -142,8 +141,7 @@ static void extract_cell(RTLIL::Cell *cell, bool keepff)
 
 		map_signal(sig_y, 'n', map_signal(sig_a));
 
-		module->cells.erase(cell->name);
-		delete cell;
+		module->remove(cell);
 		return;
 	}
 
@@ -169,8 +167,7 @@ static void extract_cell(RTLIL::Cell *cell, bool keepff)
 		else
 			log_abort();
 
-		module->cells.erase(cell->name);
-		delete cell;
+		module->remove(cell);
 		return;
 	}
 
@@ -192,8 +189,7 @@ static void extract_cell(RTLIL::Cell *cell, bool keepff)
 
 		map_signal(sig_y, 'm', mapped_a, mapped_b, mapped_s);
 
-		module->cells.erase(cell->name);
-		delete cell;
+		module->remove(cell);
 		return;
 	}
 }
@@ -722,47 +718,35 @@ static void abc_module(RTLIL::Design *design, RTLIL::Module *current_module, std
 					continue;
 				}
 				if (c->type == "\\INV") {
-					RTLIL::Cell *cell = new RTLIL::Cell;
-					cell->type = "$_INV_";
-					cell->name = remap_name(c->name);
+					RTLIL::Cell *cell = module->addCell(remap_name(c->name), "$_INV_");
 					cell->connections["\\A"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\A"].as_wire()->name)]);
 					cell->connections["\\Y"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\Y"].as_wire()->name)]);
-					module->cells[cell->name] = cell;
 					design->select(module, cell);
 					continue;
 				}
 				if (c->type == "\\AND" || c->type == "\\OR" || c->type == "\\XOR") {
-					RTLIL::Cell *cell = new RTLIL::Cell;
-					cell->type = "$_" + c->type.substr(1) + "_";
-					cell->name = remap_name(c->name);
+					RTLIL::Cell *cell = module->addCell(remap_name(c->name), "$_" + c->type.substr(1) + "_");
 					cell->connections["\\A"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\A"].as_wire()->name)]);
 					cell->connections["\\B"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\B"].as_wire()->name)]);
 					cell->connections["\\Y"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\Y"].as_wire()->name)]);
-					module->cells[cell->name] = cell;
 					design->select(module, cell);
 					continue;
 				}
 				if (c->type == "\\MUX") {
-					RTLIL::Cell *cell = new RTLIL::Cell;
-					cell->type = "$_MUX_";
-					cell->name = remap_name(c->name);
+					RTLIL::Cell *cell = module->addCell(remap_name(c->name), "$_MUX_");
 					cell->connections["\\A"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\A"].as_wire()->name)]);
 					cell->connections["\\B"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\B"].as_wire()->name)]);
 					cell->connections["\\S"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\S"].as_wire()->name)]);
 					cell->connections["\\Y"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\Y"].as_wire()->name)]);
-					module->cells[cell->name] = cell;
 					design->select(module, cell);
 					continue;
 				}
 				if (c->type == "\\DFF") {
 					log_assert(clk_sig.size() == 1);
-					RTLIL::Cell *cell = new RTLIL::Cell;
-					cell->type = clk_polarity ? "$_DFF_P_" : "$_DFF_N_";
-					cell->name = remap_name(c->name);
+					RTLIL::Cell *cell = module->addCell(remap_name(c->name), clk_polarity ? "$_DFF_P_" : "$_DFF_N_");
 					cell->connections["\\D"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\D"].as_wire()->name)]);
 					cell->connections["\\Q"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\Q"].as_wire()->name)]);
 					cell->connections["\\C"] = clk_sig;
-					module->cells[cell->name] = cell;
 					design->select(module, cell);
 					continue;
 				}
@@ -784,20 +768,15 @@ static void abc_module(RTLIL::Design *design, RTLIL::Module *current_module, std
 				}
 				if (c->type == "\\_dff_") {
 					log_assert(clk_sig.size() == 1);
-					RTLIL::Cell *cell = new RTLIL::Cell;
-					cell->type = clk_polarity ? "$_DFF_P_" : "$_DFF_N_";
-					cell->name = remap_name(c->name);
+					RTLIL::Cell *cell = module->addCell(remap_name(c->name), clk_polarity ? "$_DFF_P_" : "$_DFF_N_");
 					cell->connections["\\D"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\D"].as_wire()->name)]);
 					cell->connections["\\Q"] = RTLIL::SigSpec(module->wires[remap_name(c->connections["\\Q"].as_wire()->name)]);
 					cell->connections["\\C"] = clk_sig;
-					module->cells[cell->name] = cell;
 					design->select(module, cell);
 					continue;
 				}
-				RTLIL::Cell *cell = new RTLIL::Cell;
-				cell->type = c->type;
+				RTLIL::Cell *cell = module->addCell(remap_name(c->name), c->type);
 				cell->parameters = c->parameters;
-				cell->name = remap_name(c->name);
 				for (auto &conn : c->connections) {
 					RTLIL::SigSpec newsig;
 					for (auto &c : conn.second.chunks()) {
@@ -808,7 +787,6 @@ static void abc_module(RTLIL::Design *design, RTLIL::Module *current_module, std
 					}
 					cell->connections[conn.first] = newsig;
 				}
-				module->cells[cell->name] = cell;
 				design->select(module, cell);
 			}
 		}
diff --git a/passes/abc/blifparse.cc b/passes/abc/blifparse.cc
index 04977b369..e7feb1877 100644
--- a/passes/abc/blifparse.cc
+++ b/passes/abc/blifparse.cc
@@ -127,36 +127,27 @@ RTLIL::Design *abc_parse_blif(FILE *f, std::string dff_name)
 					module->add(wire);
 				}
 
-				RTLIL::Cell *cell = new RTLIL::Cell;
-				cell->name = NEW_ID;
-				cell->type = dff_name;
+				RTLIL::Cell *cell = module->addCell(NEW_ID, dff_name);
 				cell->connections["\\D"] = module->wires.at(RTLIL::escape_id(d));
 				cell->connections["\\Q"] = module->wires.at(RTLIL::escape_id(q));
-				module->add(cell);
 				continue;
 			}
 
 			if (!strcmp(cmd, ".gate"))
 			{
-				RTLIL::Cell *cell = new RTLIL::Cell;
-				cell->name = NEW_ID;
-				module->add(cell);
-
 				char *p = strtok(NULL, " \t\r\n");
 				if (p == NULL)
 					goto error;
-				cell->type = RTLIL::escape_id(p);
+
+				RTLIL::Cell *cell = module->addCell(NEW_ID, RTLIL::escape_id(p));
 
 				while ((p = strtok(NULL, " \t\r\n")) != NULL) {
 					char *q = strchr(p, '=');
 					if (q == NULL || !q[0] || !q[1])
 						goto error;
 					*(q++) = 0;
-					if (module->wires.count(RTLIL::escape_id(q)) == 0) {
-						RTLIL::Wire *wire = new RTLIL::Wire;
-						wire->name = RTLIL::escape_id(q);
-						module->add(wire);
-					}
+					if (module->wires.count(RTLIL::escape_id(q)) == 0)
+						module->addWire(RTLIL::escape_id(q));
 					cell->connections[RTLIL::escape_id(p)] = module->wires.at(RTLIL::escape_id(q));
 				}
 				continue;
@@ -212,16 +203,13 @@ RTLIL::Design *abc_parse_blif(FILE *f, std::string dff_name)
 					goto continue_without_read;
 				}
 
-				RTLIL::Cell *cell = new RTLIL::Cell;
-				cell->name = NEW_ID;
-				cell->type = "$lut";
+				RTLIL::Cell *cell = module->addCell(NEW_ID, "$lut");
 				cell->parameters["\\WIDTH"] = RTLIL::Const(input_sig.size());
 				cell->parameters["\\LUT"] = RTLIL::Const(RTLIL::State::Sx, 1 << input_sig.size());
 				cell->connections["\\I"] = input_sig;
 				cell->connections["\\O"] = output_sig;
 				lutptr = &cell->parameters.at("\\LUT");
 				lut_default_state = RTLIL::State::Sx;
-				module->add(cell);
 				continue;
 			}
 
diff --git a/passes/cmds/delete.cc b/passes/cmds/delete.cc
index 7fe95b0a9..79b7c3c30 100644
--- a/passes/cmds/delete.cc
+++ b/passes/cmds/delete.cc
@@ -107,7 +107,7 @@ struct DeletePass : public Pass {
 			}
 
 			std::set<std::string> delete_wires;
-			std::set<std::string> delete_cells;
+			std::set<RTLIL::Cell*> delete_cells;
 			std::set<std::string> delete_procs;
 			std::set<std::string> delete_mems;
 
@@ -121,10 +121,10 @@ struct DeletePass : public Pass {
 
 			for (auto &it : module->cells) {
 				if (design->selected(module, it.second))
-					delete_cells.insert(it.first);
+					delete_cells.insert(it.second);
 				if ((it.second->type == "$memrd" || it.second->type == "$memwr") &&
 						delete_mems.count(it.second->parameters.at("\\MEMID").decode_string()) != 0)
-					delete_cells.insert(it.first);
+					delete_cells.insert(it.second);
 			}
 
 			for (auto &it : module->processes)
@@ -147,8 +147,7 @@ struct DeletePass : public Pass {
 			}
 
 			for (auto &it : delete_cells) {
-				delete module->cells.at(it);
-				module->cells.erase(it);
+				module->remove(it);
 			}
 
 			for (auto &it : delete_procs) {
diff --git a/passes/cmds/splice.cc b/passes/cmds/splice.cc
index 68e8951ff..a470aed00 100644
--- a/passes/cmds/splice.cc
+++ b/passes/cmds/splice.cc
@@ -70,16 +70,13 @@ struct SpliceWorker
 		RTLIL::SigSpec new_sig = sig;
 
 		if (sig_a.size() != sig.size()) {
-			RTLIL::Cell *cell = new RTLIL::Cell;
-			cell->name = NEW_ID;
-			cell->type = "$slice";
+			RTLIL::Cell *cell = module->addCell(NEW_ID, "$slice");
 			cell->parameters["\\OFFSET"] = offset;
 			cell->parameters["\\A_WIDTH"] = sig_a.size();
 			cell->parameters["\\Y_WIDTH"] = sig.size();
 			cell->connections["\\A"] = sig_a;
 			cell->connections["\\Y"] = module->addWire(NEW_ID, sig.size());
 			new_sig = cell->connections["\\Y"];
-			module->add(cell);
 		}
 
 		sliced_signals_cache[sig] = new_sig;
@@ -130,16 +127,13 @@ struct SpliceWorker
 		RTLIL::SigSpec new_sig = get_sliced_signal(chunks.front());
 		for (size_t i = 1; i < chunks.size(); i++) {
 			RTLIL::SigSpec sig2 = get_sliced_signal(chunks[i]);
-			RTLIL::Cell *cell = new RTLIL::Cell;
-			cell->name = NEW_ID;
-			cell->type = "$concat";
+			RTLIL::Cell *cell = module->addCell(NEW_ID, "$concat");
 			cell->parameters["\\A_WIDTH"] = new_sig.size();
 			cell->parameters["\\B_WIDTH"] = sig2.size();
 			cell->connections["\\A"] = new_sig;
 			cell->connections["\\B"] = sig2;
 			cell->connections["\\Y"] = module->addWire(NEW_ID, new_sig.size() + sig2.size());
 			new_sig = cell->connections["\\Y"];
-			module->add(cell);
 		}
 
 		spliced_signals_cache[sig] = new_sig;
diff --git a/passes/fsm/fsm_expand.cc b/passes/fsm/fsm_expand.cc
index 0dd328db3..f3b6c998d 100644
--- a/passes/fsm/fsm_expand.cc
+++ b/passes/fsm/fsm_expand.cc
@@ -226,10 +226,8 @@ struct FsmExpand
 				merge_cell_into_fsm(c);
 		}
 
-		for (auto c : merged_set) {
-			module->cells.erase(c->name);
-			delete c;
-		}
+		for (auto c : merged_set)
+			module->remove(c);
 
 		if (merged_set.size() > 0 && !already_optimized)
 			FsmData::optimize_fsm(fsm_cell, module);
diff --git a/passes/fsm/fsm_extract.cc b/passes/fsm/fsm_extract.cc
index dfd025a51..1b5ea1bc0 100644
--- a/passes/fsm/fsm_extract.cc
+++ b/passes/fsm/fsm_extract.cc
@@ -270,9 +270,7 @@ static void extract_fsm(RTLIL::Wire *wire)
 
 	// create fsm cell
 
-	RTLIL::Cell *fsm_cell = new RTLIL::Cell;
-	fsm_cell->name = stringf("$fsm$%s$%d", wire->name.c_str(), RTLIL::autoidx++);
-	fsm_cell->type = "$fsm";
+	RTLIL::Cell *fsm_cell = module->addCell(stringf("$fsm$%s$%d", wire->name.c_str(), RTLIL::autoidx++), "$fsm");
 	fsm_cell->connections["\\CLK"] = clk;
 	fsm_cell->connections["\\ARST"] = arst;
 	fsm_cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity ? 1 : 0, 1);
@@ -282,7 +280,6 @@ static void extract_fsm(RTLIL::Wire *wire)
 	fsm_cell->parameters["\\NAME"] = RTLIL::Const(wire->name);
 	fsm_cell->attributes = wire->attributes;
 	fsm_data.copy_to_cell(fsm_cell);
-	module->cells[fsm_cell->name] = fsm_cell;
 
 	// rename original state wire
 
diff --git a/passes/fsm/fsm_map.cc b/passes/fsm/fsm_map.cc
index cee267629..78248eb6d 100644
--- a/passes/fsm/fsm_map.cc
+++ b/passes/fsm/fsm_map.cc
@@ -54,13 +54,10 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
 
 		if (eq_sig_a.size() > 0)
 		{
-			RTLIL::Wire *eq_wire = new RTLIL::Wire;
-			eq_wire->name = NEW_ID;
-			module->add(eq_wire);
+			RTLIL::Wire *eq_wire = module->addWire(NEW_ID);
+			and_sig.append(RTLIL::SigSpec(eq_wire));
 
-			RTLIL::Cell *eq_cell = new RTLIL::Cell;
-			eq_cell->name = NEW_ID;
-			eq_cell->type = "$eq";
+			RTLIL::Cell *eq_cell = module->addCell(NEW_ID, "$eq");
 			eq_cell->connections["\\A"] = eq_sig_a;
 			eq_cell->connections["\\B"] = eq_sig_b;
 			eq_cell->connections["\\Y"] = RTLIL::SigSpec(eq_wire);
@@ -69,9 +66,6 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
 			eq_cell->parameters["\\A_WIDTH"] = RTLIL::Const(eq_sig_a.size());
 			eq_cell->parameters["\\B_WIDTH"] = RTLIL::Const(eq_sig_b.size());
 			eq_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
-			module->add(eq_cell);
-
-			and_sig.append(RTLIL::SigSpec(eq_wire));
 		}
 
 		if (or_sig.size() < num_states-int(fullstate_cache.size()))
@@ -82,21 +76,15 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
 			}
 			else
 			{
-				RTLIL::Wire *or_wire = new RTLIL::Wire;
-				or_wire->name = NEW_ID;
-				module->add(or_wire);
+				RTLIL::Wire *or_wire = module->addWire(NEW_ID);
+				and_sig.append(RTLIL::SigSpec(or_wire));
 
-				RTLIL::Cell *or_cell = new RTLIL::Cell;
-				or_cell->name = NEW_ID;
-				or_cell->type = "$reduce_or";
+				RTLIL::Cell *or_cell = module->addCell(NEW_ID, "$reduce_or");
 				or_cell->connections["\\A"] = or_sig;
 				or_cell->connections["\\Y"] = RTLIL::SigSpec(or_wire);
 				or_cell->parameters["\\A_SIGNED"] = RTLIL::Const(false);
 				or_cell->parameters["\\A_WIDTH"] = RTLIL::Const(or_sig.size());
 				or_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
-				module->add(or_cell);
-
-				and_sig.append(RTLIL::SigSpec(or_wire));
 			}
 		}
 
@@ -104,13 +92,10 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
 		{
 		case 2:
 			{
-				RTLIL::Wire *and_wire = new RTLIL::Wire;
-				and_wire->name = NEW_ID;
-				module->add(and_wire);
+				RTLIL::Wire *and_wire = module->addWire(NEW_ID);
+				cases_vector.append(RTLIL::SigSpec(and_wire));
 
-				RTLIL::Cell *and_cell = new RTLIL::Cell;
-				and_cell->name = NEW_ID;
-				and_cell->type = "$and";
+				RTLIL::Cell *and_cell = module->addCell(NEW_ID, "$and");
 				and_cell->connections["\\A"] = and_sig.extract(0, 1);
 				and_cell->connections["\\B"] = and_sig.extract(1, 1);
 				and_cell->connections["\\Y"] = RTLIL::SigSpec(and_wire);
@@ -119,9 +104,6 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
 				and_cell->parameters["\\A_WIDTH"] = RTLIL::Const(1);
 				and_cell->parameters["\\B_WIDTH"] = RTLIL::Const(1);
 				and_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
-				module->add(and_cell);
-
-				cases_vector.append(RTLIL::SigSpec(and_wire));
 				break;
 			}
 		case 1:
@@ -136,15 +118,12 @@ static void implement_pattern_cache(RTLIL::Module *module, std::map<RTLIL::Const
 	}
 
 	if (cases_vector.size() > 1) {
-		RTLIL::Cell *or_cell = new RTLIL::Cell;
-		or_cell->name = NEW_ID;
-		or_cell->type = "$reduce_or";
+		RTLIL::Cell *or_cell = module->addCell(NEW_ID, "$reduce_or");
 		or_cell->connections["\\A"] = cases_vector;
 		or_cell->connections["\\Y"] = output;
 		or_cell->parameters["\\A_SIGNED"] = RTLIL::Const(false);
 		or_cell->parameters["\\A_WIDTH"] = RTLIL::Const(cases_vector.size());
 		or_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
-		module->add(or_cell);
 	} else if (cases_vector.size() == 1) {
 		module->connections.push_back(RTLIL::SigSig(output, cases_vector));
 	} else {
@@ -171,13 +150,9 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
 	state_wire->width = fsm_data.state_bits;
 	module->add(state_wire);
 
-	RTLIL::Wire *next_state_wire = new RTLIL::Wire;
-	next_state_wire->name = NEW_ID;
-	next_state_wire->width = fsm_data.state_bits;
-	module->add(next_state_wire);
+	RTLIL::Wire *next_state_wire = module->addWire(NEW_ID, fsm_data.state_bits);
 
-	RTLIL::Cell *state_dff = new RTLIL::Cell;
-	state_dff->name = NEW_ID;
+	RTLIL::Cell *state_dff = module->addCell(NEW_ID, "");
 	if (fsm_cell->connections["\\ARST"].is_fully_const()) {
 		state_dff->type = "$dff";
 	} else {
@@ -194,16 +169,12 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
 	state_dff->connections["\\CLK"] = fsm_cell->connections["\\CLK"];
 	state_dff->connections["\\D"] = RTLIL::SigSpec(next_state_wire);
 	state_dff->connections["\\Q"] = RTLIL::SigSpec(state_wire);
-	module->add(state_dff);
 
 	// decode state register
 
 	bool encoding_is_onehot = true;
 
-	RTLIL::Wire *state_onehot = new RTLIL::Wire;
-	state_onehot->name = NEW_ID;
-	state_onehot->width = fsm_data.state_table.size();
-	module->add(state_onehot);
+	RTLIL::Wire *state_onehot = module->addWire(NEW_ID, fsm_data.state_table.size());
 
 	for (size_t i = 0; i < fsm_data.state_table.size(); i++)
 	{
@@ -224,9 +195,7 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
 		{
 			encoding_is_onehot = false;
 
-			RTLIL::Cell *eq_cell = new RTLIL::Cell;
-			eq_cell->name = NEW_ID;
-			eq_cell->type = "$eq";
+			RTLIL::Cell *eq_cell = module->addCell(NEW_ID, "$eq");
 			eq_cell->connections["\\A"] = sig_a;
 			eq_cell->connections["\\B"] = sig_b;
 			eq_cell->connections["\\Y"] = RTLIL::SigSpec(state_onehot, i);
@@ -235,7 +204,6 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
 			eq_cell->parameters["\\A_WIDTH"] = RTLIL::Const(sig_a.size());
 			eq_cell->parameters["\\B_WIDTH"] = RTLIL::Const(sig_b.size());
 			eq_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
-			module->add(eq_cell);
 		}
 	}
 
@@ -296,16 +264,13 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
 			}
 		}
 
-		RTLIL::Cell *mux_cell = new RTLIL::Cell;
-		mux_cell->name = NEW_ID;
-		mux_cell->type = "$safe_pmux";
+		RTLIL::Cell *mux_cell = module->addCell(NEW_ID, "$safe_pmux");
 		mux_cell->connections["\\A"] = sig_a;
 		mux_cell->connections["\\B"] = sig_b;
 		mux_cell->connections["\\S"] = sig_s;
 		mux_cell->connections["\\Y"] = RTLIL::SigSpec(next_state_wire);
 		mux_cell->parameters["\\WIDTH"] = RTLIL::Const(sig_a.size());
 		mux_cell->parameters["\\S_WIDTH"] = RTLIL::Const(sig_s.size());
-		module->add(mux_cell);
 	}
 
 	// Generate ctrl_out signal
@@ -335,8 +300,7 @@ static void map_fsm(RTLIL::Cell *fsm_cell, RTLIL::Module *module)
 
 	// Remove FSM cell
 
-	module->cells.erase(fsm_cell->name);
-	delete fsm_cell;
+	module->remove(fsm_cell);
 }
 
 struct FsmMapPass : public Pass {
diff --git a/passes/hierarchy/submod.cc b/passes/hierarchy/submod.cc
index 257301880..204f899a0 100644
--- a/passes/hierarchy/submod.cc
+++ b/passes/hierarchy/submod.cc
@@ -162,7 +162,10 @@ struct SubmodWorker
 		}
 
 		for (RTLIL::Cell *cell : submod.cells) {
-			RTLIL::Cell *new_cell = new RTLIL::Cell(*cell);
+			RTLIL::Cell *new_cell = new_mod->addCell(cell->name, cell->type);
+			new_cell->connections = cell->connections;
+			new_cell->parameters = cell->parameters;
+			new_cell->attributes = cell->attributes;
 			for (auto &conn : new_cell->connections)
 				for (auto &bit : conn.second)
 					if (bit.wire != NULL) {
@@ -170,15 +173,11 @@ struct SubmodWorker
 						bit.wire = wire_flags[bit.wire].new_wire;
 					}
 			log("  cell %s (%s)\n", new_cell->name.c_str(), new_cell->type.c_str());
-			new_mod->cells[new_cell->name] = new_cell;
-			module->cells.erase(cell->name);
-			delete cell;
+			module->remove(cell);
 		}
 		submod.cells.clear();
 
-		RTLIL::Cell *new_cell = new RTLIL::Cell;
-		new_cell->name = submod.full_name;
-		new_cell->type = submod.full_name;
+		RTLIL::Cell *new_cell = module->addCell(submod.full_name, submod.full_name);
 		for (auto &it : wire_flags)
 		{
 			RTLIL::Wire *old_wire = it.first;
@@ -186,7 +185,6 @@ struct SubmodWorker
 			if (new_wire->port_id > 0)
 				new_cell->connections[new_wire->name] = RTLIL::SigSpec(old_wire);
 		}
-		module->cells[new_cell->name] = new_cell;
 	}
 
 	SubmodWorker(RTLIL::Design *design, RTLIL::Module *module, std::string opt_name = std::string()) : design(design), module(module), opt_name(opt_name)
diff --git a/passes/memory/memory_collect.cc b/passes/memory/memory_collect.cc
index 3ceb5da36..116b704e3 100644
--- a/passes/memory/memory_collect.cc
+++ b/passes/memory/memory_collect.cc
@@ -58,7 +58,7 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Memory *memory)
 	RTLIL::SigSpec sig_rd_addr;
 	RTLIL::SigSpec sig_rd_data;
 
-	std::vector<std::string> del_cell_ids;
+	std::vector<RTLIL::Cell*> del_cells;
 	std::vector<RTLIL::Cell*> memcells;
 
 	for (auto &cell_it : module->cells) {
@@ -74,7 +74,7 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Memory *memory)
 		if (cell->type == "$memwr" && cell->parameters["\\MEMID"].decode_string() == memory->name)
 		{
 			wr_ports++;
-			del_cell_ids.push_back(cell->name);
+			del_cells.push_back(cell);
 
 			RTLIL::SigSpec clk = cell->connections["\\CLK"];
 			RTLIL::SigSpec clk_enable = RTLIL::SigSpec(cell->parameters["\\CLK_ENABLE"]);
@@ -101,7 +101,7 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Memory *memory)
 		if (cell->type == "$memrd" && cell->parameters["\\MEMID"].decode_string() == memory->name)
 		{
 			rd_ports++;
-			del_cell_ids.push_back(cell->name);
+			del_cells.push_back(cell);
 
 			RTLIL::SigSpec clk = cell->connections["\\CLK"];
 			RTLIL::SigSpec clk_enable = RTLIL::SigSpec(cell->parameters["\\CLK_ENABLE"]);
@@ -129,10 +129,7 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Memory *memory)
 	std::stringstream sstr;
 	sstr << "$mem$" << memory->name << "$" << (RTLIL::autoidx++);
 
-	RTLIL::Cell *mem = new RTLIL::Cell;
-	mem->name = sstr.str();
-	mem->type = "$mem";
-
+	RTLIL::Cell *mem = module->addCell(sstr.str(), "$mem");
 	mem->parameters["\\MEMID"] = RTLIL::Const(memory->name);
 	mem->parameters["\\WIDTH"] = RTLIL::Const(memory->width);
 	mem->parameters["\\OFFSET"] = RTLIL::Const(memory->start_offset);
@@ -170,11 +167,8 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Memory *memory)
 	mem->connections["\\RD_ADDR"] = sig_rd_addr;
 	mem->connections["\\RD_DATA"] = sig_rd_data;
 
-	for (auto &id : del_cell_ids) {
-		delete module->cells[id];
-		module->cells.erase(id);
-	}
-	module->cells[mem->name] = mem;
+	for (auto c : del_cells)
+		module->remove(c);
 }
 
 static void handle_module(RTLIL::Design *design, RTLIL::Module *module)
diff --git a/passes/memory/memory_map.cc b/passes/memory/memory_map.cc
index e605e6e51..b5f0520a4 100644
--- a/passes/memory/memory_map.cc
+++ b/passes/memory/memory_map.cc
@@ -57,8 +57,7 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 
 	// delete unused memory cell
 	if (cell->parameters["\\RD_PORTS"].as_int() == 0 && cell->parameters["\\WR_PORTS"].as_int() == 0) {
-		module->cells.erase(cell->name);
-		delete cell;
+		module->remove(cell);
 		return;
 	}
 
@@ -117,9 +116,7 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 		}
 		else
 		{
-			RTLIL::Cell *c = new RTLIL::Cell;
-			c->name = genid(cell->name, "", i);
-			c->type = "$dff";
+			RTLIL::Cell *c = module->addCell(genid(cell->name, "", i), "$dff");
 			c->parameters["\\WIDTH"] = cell->parameters["\\WIDTH"];
 			if (clocks_pol.bits.size() > 0) {
 				c->parameters["\\CLK_POLARITY"] = RTLIL::Const(clocks_pol.bits[0]);
@@ -128,7 +125,6 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 				c->parameters["\\CLK_POLARITY"] = RTLIL::Const(RTLIL::State::S1);
 				c->connections["\\CLK"] = RTLIL::SigSpec(RTLIL::State::S0);
 			}
-			module->cells[c->name] = c;
 
 			RTLIL::Wire *w_in = new RTLIL::Wire;
 			w_in->name = genid(cell->name, "", i, "$d");
@@ -164,14 +160,11 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 		{
 			if (cell->parameters["\\RD_TRANSPARENT"].bits[i] == RTLIL::State::S1)
 			{
-				RTLIL::Cell *c = new RTLIL::Cell;
-				c->name = genid(cell->name, "$rdreg", i);
-				c->type = "$dff";
+				RTLIL::Cell *c = module->addCell(genid(cell->name, "$rdreg", i), "$dff");
 				c->parameters["\\WIDTH"] = RTLIL::Const(mem_abits);
 				c->parameters["\\CLK_POLARITY"] = RTLIL::Const(cell->parameters["\\RD_CLK_POLARITY"].bits[i]);
 				c->connections["\\CLK"] = cell->connections["\\RD_CLK"].extract(i, 1);
 				c->connections["\\D"] = rd_addr;
-				module->cells[c->name] = c;
 				count_dff++;
 
 				RTLIL::Wire *w = new RTLIL::Wire;
@@ -184,14 +177,11 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 			}
 			else
 			{
-				RTLIL::Cell *c = new RTLIL::Cell;
-				c->name = genid(cell->name, "$rdreg", i);
-				c->type = "$dff";
+				RTLIL::Cell *c = module->addCell(genid(cell->name, "$rdreg", i), "$dff");
 				c->parameters["\\WIDTH"] = cell->parameters["\\WIDTH"];
 				c->parameters["\\CLK_POLARITY"] = RTLIL::Const(cell->parameters["\\RD_CLK_POLARITY"].bits[i]);
 				c->connections["\\CLK"] = cell->connections["\\RD_CLK"].extract(i, 1);
 				c->connections["\\Q"] = rd_signals.back();
-				module->cells[c->name] = c;
 				count_dff++;
 
 				RTLIL::Wire *w = new RTLIL::Wire;
@@ -211,13 +201,10 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 
 			for (size_t k = 0; k < rd_signals.size(); k++)
 			{
-				RTLIL::Cell *c = new RTLIL::Cell;
-				c->name = genid(cell->name, "$rdmux", i, "", j, "", k);
-				c->type = "$mux";
+				RTLIL::Cell *c = module->addCell(genid(cell->name, "$rdmux", i, "", j, "", k), "$mux");
 				c->parameters["\\WIDTH"] = cell->parameters["\\WIDTH"];
 				c->connections["\\Y"] = rd_signals[k];
 				c->connections["\\S"] = rd_addr.extract(mem_abits-j-1, 1);
-				module->cells[c->name] = c;
 				count_mux++;
 
 				RTLIL::Wire *w = new RTLIL::Wire;
@@ -258,9 +245,7 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 			RTLIL::SigSpec wr_data = cell->connections["\\WR_DATA"].extract(j*mem_width, mem_width);
 			RTLIL::SigSpec wr_en = cell->connections["\\WR_EN"].extract(j*mem_width, mem_width);
 
-			RTLIL::Cell *c = new RTLIL::Cell;
-			c->name = genid(cell->name, "$wreq", i, "", j);
-			c->type = "$eq";
+			RTLIL::Cell *c = module->addCell(genid(cell->name, "$wreq", i, "", j), "$eq");
 			c->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 			c->parameters["\\B_SIGNED"] = RTLIL::Const(0);
 			c->parameters["\\A_WIDTH"] = cell->parameters["\\ABITS"];
@@ -268,7 +253,6 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 			c->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
 			c->connections["\\A"] = RTLIL::SigSpec(i, mem_abits);
 			c->connections["\\B"] = wr_addr;
-			module->cells[c->name] = c;
 			count_wrmux++;
 
 			RTLIL::Wire *w_seladdr = new RTLIL::Wire;
@@ -293,9 +277,7 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 
 				if (wr_bit != RTLIL::SigSpec(1, 1))
 				{
-					c = new RTLIL::Cell;
-					c->name = genid(cell->name, "$wren", i, "", j, "", wr_offset);
-					c->type = "$and";
+					c = module->addCell(genid(cell->name, "$wren", i, "", j, "", wr_offset), "$and");
 					c->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 					c->parameters["\\B_SIGNED"] = RTLIL::Const(0);
 					c->parameters["\\A_WIDTH"] = RTLIL::Const(1);
@@ -303,7 +285,6 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 					c->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
 					c->connections["\\A"] = w;
 					c->connections["\\B"] = wr_bit;
-					module->cells[c->name] = c;
 
 					w = new RTLIL::Wire;
 					w->name = genid(cell->name, "$wren", i, "", j, "", wr_offset, "$y");
@@ -311,14 +292,11 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 					c->connections["\\Y"] = RTLIL::SigSpec(w);
 				}
 
-				c = new RTLIL::Cell;
-				c->name = genid(cell->name, "$wrmux", i, "", j, "", wr_offset);
-				c->type = "$mux";
+				c = module->addCell(genid(cell->name, "$wrmux", i, "", j, "", wr_offset), "$mux");
 				c->parameters["\\WIDTH"] = wr_width;
 				c->connections["\\A"] = sig.extract(wr_offset, wr_width);
 				c->connections["\\B"] = wr_data.extract(wr_offset, wr_width);
 				c->connections["\\S"] = RTLIL::SigSpec(w);
-				module->cells[c->name] = c;
 
 				w = new RTLIL::Wire;
 				w->name = genid(cell->name, "$wrmux", i, "", j, "", wr_offset, "$y");
@@ -336,9 +314,7 @@ static void handle_cell(RTLIL::Module *module, RTLIL::Cell *cell)
 
 	log("  write interface: %d blocks of $eq, $and and $mux cells.\n", count_wrmux);
 
-	module->cells.erase(cell->name);
-	delete cell;
-	return;
+	module->remove(cell);
 }
 
 static void handle_module(RTLIL::Design *design, RTLIL::Module *module)
diff --git a/passes/memory/memory_share.cc b/passes/memory/memory_share.cc
index dd2a32cad..63f6b14f8 100644
--- a/passes/memory/memory_share.cc
+++ b/passes/memory/memory_share.cc
@@ -446,8 +446,7 @@ struct MemoryShareWorker
 				cell->connections.at("\\EN") = merged_en;
 				cell->connections.at("\\DATA") = merged_data;
 
-				module->cells.erase(wr_ports[last_i]->name);
-				delete wr_ports[last_i];
+				module->remove(wr_ports[last_i]);
 				wr_ports[last_i] = NULL;
 
 				log("      Active bits: ");
@@ -617,8 +616,7 @@ struct MemoryShareWorker
 			module->addMux(NEW_ID, grouped_last_en, grouped_this_en, this_en_active, grouped_en);
 			wr_ports[i]->connections.at("\\EN") = en;
 
-			module->cells.erase(wr_ports[i-1]->name);
-			delete wr_ports[i-1];
+			module->remove(wr_ports[i-1]);
 			wr_ports[i-1] = NULL;
 		}
 
diff --git a/passes/memory/memory_unpack.cc b/passes/memory/memory_unpack.cc
index bbd015833..97cda1443 100644
--- a/passes/memory/memory_unpack.cc
+++ b/passes/memory/memory_unpack.cc
@@ -47,9 +47,7 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Cell *memory)
 
 	for (int i = 0; i < num_rd_ports; i++)
 	{
-		RTLIL::Cell *cell = new RTLIL::Cell;
-		cell->name = NEW_ID;
-		cell->type = "$memrd";
+		RTLIL::Cell *cell = module->addCell(NEW_ID, "$memrd");
 		cell->parameters["\\MEMID"] = mem_name;
 		cell->parameters["\\ABITS"] = memory->parameters.at("\\ABITS");
 		cell->parameters["\\WIDTH"] = memory->parameters.at("\\WIDTH");
@@ -59,14 +57,11 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Cell *memory)
 		cell->connections["\\CLK"] = memory->connections.at("\\RD_CLK").extract(i, 1);
 		cell->connections["\\ADDR"] = memory->connections.at("\\RD_ADDR").extract(i*abits, abits);
 		cell->connections["\\DATA"] = memory->connections.at("\\RD_DATA").extract(i*mem->width, mem->width);
-		module->add(cell);
 	}
 
 	for (int i = 0; i < num_wr_ports; i++)
 	{
-		RTLIL::Cell *cell = new RTLIL::Cell;
-		cell->name = NEW_ID;
-		cell->type = "$memwr";
+		RTLIL::Cell *cell = module->addCell(NEW_ID, "$memwr");
 		cell->parameters["\\MEMID"] = mem_name;
 		cell->parameters["\\ABITS"] = memory->parameters.at("\\ABITS");
 		cell->parameters["\\WIDTH"] = memory->parameters.at("\\WIDTH");
@@ -77,11 +72,9 @@ static void handle_memory(RTLIL::Module *module, RTLIL::Cell *memory)
 		cell->connections["\\EN"] = memory->connections.at("\\WR_EN").extract(i*mem->width, mem->width);
 		cell->connections["\\ADDR"] = memory->connections.at("\\WR_ADDR").extract(i*abits, abits);
 		cell->connections["\\DATA"] = memory->connections.at("\\WR_DATA").extract(i*mem->width, mem->width);
-		module->add(cell);
 	}
 
-	module->cells.erase(memory->name);
-	delete memory;
+	module->remove(memory);
 }
 
 static void handle_module(RTLIL::Design *design, RTLIL::Module *module)
diff --git a/passes/opt/opt_clean.cc b/passes/opt/opt_clean.cc
index 02efabf72..00fa6031f 100644
--- a/passes/opt/opt_clean.cc
+++ b/passes/opt/opt_clean.cc
@@ -90,9 +90,8 @@ static void rmunused_module_cells(RTLIL::Module *module, bool verbose)
 		if (verbose)
 			log("  removing unused `%s' cell `%s'.\n", cell->type.c_str(), cell->name.c_str());
 		OPT_DID_SOMETHING = true;
-		module->cells.erase(cell->name);
+		module->remove(cell);
 		count_rm_cells++;
-		delete cell;
 	}
 }
 
diff --git a/passes/opt/opt_const.cc b/passes/opt/opt_const.cc
index e2bf7004f..e1b6c598f 100644
--- a/passes/opt/opt_const.cc
+++ b/passes/opt/opt_const.cc
@@ -81,8 +81,7 @@ static void replace_cell(RTLIL::Module *module, RTLIL::Cell *cell, std::string i
 			module->name.c_str(), log_signal(Y), log_signal(out_val));
 	// ILANG_BACKEND::dump_cell(stderr, "--> ", cell);
 	module->connections.push_back(RTLIL::SigSig(Y, out_val));
-	module->cells.erase(cell->name);
-	delete cell;
+	module->remove(cell);
 	OPT_DID_SOMETHING = true;
 	did_something = true;
 }
diff --git a/passes/opt/opt_muxtree.cc b/passes/opt/opt_muxtree.cc
index dfcd55126..750a9d417 100644
--- a/passes/opt/opt_muxtree.cc
+++ b/passes/opt/opt_muxtree.cc
@@ -190,8 +190,7 @@ struct OptMuxtreeWorker
 				continue;
 
 			if (live_ports.size() == 0) {
-				module->cells.erase(mi.cell->name);
-				delete mi.cell;
+				module->remove(mi.cell);
 				continue;
 			}
 
@@ -207,8 +206,7 @@ struct OptMuxtreeWorker
 			{
 				RTLIL::SigSpec sig_in = sig_ports.extract(live_ports[0]*sig_a.size(), sig_a.size());
 				module->connections.push_back(RTLIL::SigSig(sig_y, sig_in));
-				module->cells.erase(mi.cell->name);
-				delete mi.cell;
+				module->remove(mi.cell);
 			}
 			else
 			{
diff --git a/passes/opt/opt_reduce.cc b/passes/opt/opt_reduce.cc
index 0cc16ee67..073af3087 100644
--- a/passes/opt/opt_reduce.cc
+++ b/passes/opt/opt_reduce.cc
@@ -124,19 +124,13 @@ struct OptReduceWorker
 
 			if (this_s.size() > 1)
 			{
-				RTLIL::Wire *reduce_or_wire = new RTLIL::Wire;
-				reduce_or_wire->name = NEW_ID;
-				module->wires[reduce_or_wire->name] = reduce_or_wire;
-
-				RTLIL::Cell *reduce_or_cell = new RTLIL::Cell;
-				reduce_or_cell->name = NEW_ID;
-				reduce_or_cell->type = "$reduce_or";
+				RTLIL::Cell *reduce_or_cell = module->addCell(NEW_ID, "$reduce_or");
 				reduce_or_cell->connections["\\A"] = this_s;
 				reduce_or_cell->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 				reduce_or_cell->parameters["\\A_WIDTH"] = RTLIL::Const(this_s.size());
 				reduce_or_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
-				module->cells[reduce_or_cell->name] = reduce_or_cell;
 
+				RTLIL::Wire *reduce_or_wire = module->addWire(NEW_ID);
 				this_s = RTLIL::SigSpec(reduce_or_wire);
 				reduce_or_cell->connections["\\Y"] = this_s;
 			}
@@ -157,8 +151,7 @@ struct OptReduceWorker
 		{
 			module->connections.push_back(RTLIL::SigSig(cell->connections["\\Y"], cell->connections["\\A"]));
 			assign_map.add(cell->connections["\\Y"], cell->connections["\\A"]);
-			module->cells.erase(cell->name);
-			delete cell;
+			module->remove(cell);
 		}
 		else
 		{
diff --git a/passes/opt/opt_rmdff.cc b/passes/opt/opt_rmdff.cc
index 4215a7b54..6a35cb618 100644
--- a/passes/opt/opt_rmdff.cc
+++ b/passes/opt/opt_rmdff.cc
@@ -143,8 +143,7 @@ static bool handle_dff(RTLIL::Module *mod, RTLIL::Cell *dff)
 delete_dff:
 	log("Removing %s (%s) from module %s.\n", dff->name.c_str(), dff->type.c_str(), mod->name.c_str());
 	OPT_DID_SOMETHING = true;
-	mod->cells.erase(dff->name);
-	delete dff;
+	mod->remove(dff);
 	return true;
 }
 
diff --git a/passes/opt/opt_share.cc b/passes/opt/opt_share.cc
index 819a0e460..e3e9511fd 100644
--- a/passes/opt/opt_share.cc
+++ b/passes/opt/opt_share.cc
@@ -271,10 +271,9 @@ struct OptShareWorker
 						}
 					}
 					log("    Removing %s cell `%s' from module `%s'.\n", cell->type.c_str(), cell->name.c_str(), module->name.c_str());
-					module->cells.erase(cell->name);
+					module->remove(cell);
 					OPT_DID_SOMETHING = true;
 					total_count++;
-					delete cell;
 				} else {
 					sharemap[cell] = cell;
 				}
diff --git a/passes/proc/proc_dff.cc b/passes/proc/proc_dff.cc
index 5982fd8e4..876adb0db 100644
--- a/passes/proc/proc_dff.cc
+++ b/passes/proc/proc_dff.cc
@@ -73,79 +73,59 @@ static void gen_dffsr_complex(RTLIL::Module *mod, RTLIL::SigSpec sig_d, RTLIL::S
 				log_abort();
 
 		if (sync_low_signals.size() > 1) {
-			RTLIL::Cell *cell = new RTLIL::Cell;
-			cell->name = NEW_ID;
-			cell->type = "$reduce_or";
+			RTLIL::Cell *cell = mod->addCell(NEW_ID, "$reduce_or");
 			cell->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 			cell->parameters["\\A_WIDTH"] = RTLIL::Const(sync_low_signals.size());
 			cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
 			cell->connections["\\A"] = sync_low_signals;
 			cell->connections["\\Y"] = sync_low_signals = mod->addWire(NEW_ID);
-			mod->add(cell);
 		}
 
 		if (sync_low_signals.size() > 0) {
-			RTLIL::Cell *cell = new RTLIL::Cell;
-			cell->name = NEW_ID;
-			cell->type = "$not";
+			RTLIL::Cell *cell = mod->addCell(NEW_ID, "$not");
 			cell->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 			cell->parameters["\\A_WIDTH"] = RTLIL::Const(sync_low_signals.size());
 			cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
 			cell->connections["\\A"] = sync_low_signals;
 			cell->connections["\\Y"] = mod->addWire(NEW_ID);
 			sync_high_signals.append(cell->connections["\\Y"]);
-			mod->add(cell);
 		}
 
 		if (sync_high_signals.size() > 1) {
-			RTLIL::Cell *cell = new RTLIL::Cell;
-			cell->name = NEW_ID;
-			cell->type = "$reduce_or";
+			RTLIL::Cell *cell = mod->addCell(NEW_ID, "$reduce_or");
 			cell->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 			cell->parameters["\\A_WIDTH"] = RTLIL::Const(sync_high_signals.size());
 			cell->parameters["\\Y_WIDTH"] = RTLIL::Const(1);
 			cell->connections["\\A"] = sync_high_signals;
 			cell->connections["\\Y"] = sync_high_signals = mod->addWire(NEW_ID);
-			mod->add(cell);
 		}
 
-		RTLIL::Cell *inv_cell = new RTLIL::Cell;
-		inv_cell->name = NEW_ID;
-		inv_cell->type = "$not";
+		RTLIL::Cell *inv_cell = mod->addCell(NEW_ID, "$not");
 		inv_cell->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 		inv_cell->parameters["\\A_WIDTH"] = RTLIL::Const(sig_d.size());
 		inv_cell->parameters["\\Y_WIDTH"] = RTLIL::Const(sig_d.size());
 		inv_cell->connections["\\A"] = sync_value;
 		inv_cell->connections["\\Y"] = sync_value_inv = mod->addWire(NEW_ID, sig_d.size());
-		mod->add(inv_cell);
 
-		RTLIL::Cell *mux_set_cell = new RTLIL::Cell;
-		mux_set_cell->name = NEW_ID;
-		mux_set_cell->type = "$mux";
+		RTLIL::Cell *mux_set_cell = mod->addCell(NEW_ID, "$mux");
 		mux_set_cell->parameters["\\WIDTH"] = RTLIL::Const(sig_d.size());
 		mux_set_cell->connections["\\A"] = sig_sr_set;
 		mux_set_cell->connections["\\B"] = sync_value;
 		mux_set_cell->connections["\\S"] = sync_high_signals;
 		mux_set_cell->connections["\\Y"] = sig_sr_set = mod->addWire(NEW_ID, sig_d.size());
-		mod->add(mux_set_cell);
 
-		RTLIL::Cell *mux_clr_cell = new RTLIL::Cell;
-		mux_clr_cell->name = NEW_ID;
-		mux_clr_cell->type = "$mux";
+		RTLIL::Cell *mux_clr_cell = mod->addCell(NEW_ID, "$mux");
 		mux_clr_cell->parameters["\\WIDTH"] = RTLIL::Const(sig_d.size());
 		mux_clr_cell->connections["\\A"] = sig_sr_clr;
 		mux_clr_cell->connections["\\B"] = sync_value_inv;
 		mux_clr_cell->connections["\\S"] = sync_high_signals;
 		mux_clr_cell->connections["\\Y"] = sig_sr_clr = mod->addWire(NEW_ID, sig_d.size());
-		mod->add(mux_clr_cell);
 	}
 
 	std::stringstream sstr;
 	sstr << "$procdff$" << (RTLIL::autoidx++);
 
-	RTLIL::Cell *cell = new RTLIL::Cell;
-	cell->name = sstr.str();
-	cell->type = "$dffsr";
+	RTLIL::Cell *cell = mod->addCell(sstr.str(), "$dffsr");
 	cell->attributes = proc->attributes;
 	cell->parameters["\\WIDTH"] = RTLIL::Const(sig_d.size());
 	cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity, 1);
@@ -156,7 +136,6 @@ static void gen_dffsr_complex(RTLIL::Module *mod, RTLIL::SigSpec sig_d, RTLIL::S
 	cell->connections["\\CLK"] = clk;
 	cell->connections["\\SET"] = sig_sr_set;
 	cell->connections["\\CLR"] = sig_sr_clr;
-	mod->add(cell);
 
 	log("  created %s cell `%s' with %s edge clock and multiple level-sensitive resets.\n",
 			cell->type.c_str(), cell->name.c_str(), clk_polarity ? "positive" : "negative");
@@ -172,39 +151,28 @@ static void gen_dffsr(RTLIL::Module *mod, RTLIL::SigSpec sig_in, RTLIL::SigSpec
 	RTLIL::SigSpec sig_sr_set = mod->addWire(NEW_ID, sig_in.size());
 	RTLIL::SigSpec sig_sr_clr = mod->addWire(NEW_ID, sig_in.size());
 
-	RTLIL::Cell *inv_set = new RTLIL::Cell;
-	inv_set->name = NEW_ID;
-	inv_set->type = "$not";
+	RTLIL::Cell *inv_set = mod->addCell(NEW_ID, "$not");
 	inv_set->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 	inv_set->parameters["\\A_WIDTH"] = RTLIL::Const(sig_in.size());
 	inv_set->parameters["\\Y_WIDTH"] = RTLIL::Const(sig_in.size());
 	inv_set->connections["\\A"] = sig_set;
 	inv_set->connections["\\Y"] = sig_set_inv;
-	mod->add(inv_set);
 
-	RTLIL::Cell *mux_sr_set = new RTLIL::Cell;
-	mux_sr_set->name = NEW_ID;
-	mux_sr_set->type = "$mux";
+	RTLIL::Cell *mux_sr_set = mod->addCell(NEW_ID, "$mux");
 	mux_sr_set->parameters["\\WIDTH"] = RTLIL::Const(sig_in.size());
 	mux_sr_set->connections[set_polarity ? "\\A" : "\\B"] = RTLIL::Const(0, sig_in.size());
 	mux_sr_set->connections[set_polarity ? "\\B" : "\\A"] = sig_set;
 	mux_sr_set->connections["\\Y"] = sig_sr_set;
 	mux_sr_set->connections["\\S"] = set;
-	mod->add(mux_sr_set);
 
-	RTLIL::Cell *mux_sr_clr = new RTLIL::Cell;
-	mux_sr_clr->name = NEW_ID;
-	mux_sr_clr->type = "$mux";
+	RTLIL::Cell *mux_sr_clr = mod->addCell(NEW_ID, "$mux");
 	mux_sr_clr->parameters["\\WIDTH"] = RTLIL::Const(sig_in.size());
 	mux_sr_clr->connections[set_polarity ? "\\A" : "\\B"] = RTLIL::Const(0, sig_in.size());
 	mux_sr_clr->connections[set_polarity ? "\\B" : "\\A"] = sig_set_inv;
 	mux_sr_clr->connections["\\Y"] = sig_sr_clr;
 	mux_sr_clr->connections["\\S"] = set;
-	mod->add(mux_sr_clr);
 
-	RTLIL::Cell *cell = new RTLIL::Cell;
-	cell->name = sstr.str();
-	cell->type = "$dffsr";
+	RTLIL::Cell *cell = mod->addCell(sstr.str(), "$dffsr");
 	cell->attributes = proc->attributes;
 	cell->parameters["\\WIDTH"] = RTLIL::Const(sig_in.size());
 	cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity, 1);
@@ -215,7 +183,6 @@ static void gen_dffsr(RTLIL::Module *mod, RTLIL::SigSpec sig_in, RTLIL::SigSpec
 	cell->connections["\\CLK"] = clk;
 	cell->connections["\\SET"] = sig_sr_set;
 	cell->connections["\\CLR"] = sig_sr_clr;
-	mod->add(cell);
 
 	log("  created %s cell `%s' with %s edge clock and %s level non-const reset.\n", cell->type.c_str(), cell->name.c_str(),
 			clk_polarity ? "positive" : "negative", set_polarity ? "positive" : "negative");
@@ -227,11 +194,8 @@ static void gen_dff(RTLIL::Module *mod, RTLIL::SigSpec sig_in, RTLIL::Const val_
 	std::stringstream sstr;
 	sstr << "$procdff$" << (RTLIL::autoidx++);
 
-	RTLIL::Cell *cell = new RTLIL::Cell;
-	cell->name = sstr.str();
-	cell->type = arst ? "$adff" : "$dff";
+	RTLIL::Cell *cell = mod->addCell(sstr.str(), arst ? "$adff" : "$dff");
 	cell->attributes = proc->attributes;
-	mod->cells[cell->name] = cell;
 
 	cell->parameters["\\WIDTH"] = RTLIL::Const(sig_in.size());
 	if (arst) {
@@ -326,9 +290,7 @@ static void proc_dff(RTLIL::Module *mod, RTLIL::Process *proc, ConstEval &ce)
 				}
 				assert(inputs.size() == compare.size());
 
-				RTLIL::Cell *cell = new RTLIL::Cell;
-				cell->name = NEW_ID;
-				cell->type = "$ne";
+				RTLIL::Cell *cell = mod->addCell(NEW_ID, "$ne");
 				cell->parameters["\\A_SIGNED"] = RTLIL::Const(false, 1);
 				cell->parameters["\\B_SIGNED"] = RTLIL::Const(false, 1);
 				cell->parameters["\\A_WIDTH"] = RTLIL::Const(inputs.size());
@@ -337,7 +299,6 @@ static void proc_dff(RTLIL::Module *mod, RTLIL::Process *proc, ConstEval &ce)
 				cell->connections["\\A"] = inputs;
 				cell->connections["\\B"] = compare;
 				cell->connections["\\Y"] = sync_level->signal;
-				mod->add(cell);
 
 				many_async_rules.clear();
 			}
diff --git a/passes/proc/proc_mux.cc b/passes/proc/proc_mux.cc
index 804c51fd3..5bb1ab948 100644
--- a/passes/proc/proc_mux.cc
+++ b/passes/proc/proc_mux.cc
@@ -86,13 +86,8 @@ static RTLIL::SigSpec gen_cmp(RTLIL::Module *mod, const RTLIL::SigSpec &signal,
 		else
 		{
 			// create compare cell
-			RTLIL::Cell *eq_cell = new RTLIL::Cell;
-			std::stringstream sstr2;
-			sstr2 << sstr.str() << "_CMP" << cmp_wire->width;
-			eq_cell->name = sstr2.str();
-			eq_cell->type = "$eq";
+			RTLIL::Cell *eq_cell = mod->addCell(stringf("%s_CMP%d", sstr.str().c_str(), cmp_wire->width), "$eq");
 			eq_cell->attributes = sw->attributes;
-			mod->cells[eq_cell->name] = eq_cell;
 
 			eq_cell->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 			eq_cell->parameters["\\B_SIGNED"] = RTLIL::Const(0);
@@ -120,11 +115,8 @@ static RTLIL::SigSpec gen_cmp(RTLIL::Module *mod, const RTLIL::SigSpec &signal,
 		mod->wires[ctrl_wire->name] = ctrl_wire;
 
 		// reduce cmp vector to one logic signal
-		RTLIL::Cell *any_cell = new RTLIL::Cell;
-		any_cell->name = sstr.str() + "_ANY";
-		any_cell->type = "$reduce_or";
+		RTLIL::Cell *any_cell = mod->addCell(sstr.str() + "_ANY", "$reduce_or");
 		any_cell->attributes = sw->attributes;
-		mod->cells[any_cell->name] = any_cell;
 
 		any_cell->parameters["\\A_SIGNED"] = RTLIL::Const(0);
 		any_cell->parameters["\\A_WIDTH"] = RTLIL::Const(cmp_wire->width);
@@ -161,11 +153,8 @@ static RTLIL::SigSpec gen_mux(RTLIL::Module *mod, const RTLIL::SigSpec &signal,
 	mod->wires[result_wire->name] = result_wire;
 
 	// create the multiplexer itself
-	RTLIL::Cell *mux_cell = new RTLIL::Cell;
-	mux_cell->name = sstr.str();
-	mux_cell->type = "$mux";
+	RTLIL::Cell *mux_cell = mod->addCell(sstr.str(), "$mux");
 	mux_cell->attributes = sw->attributes;
-	mod->cells[mux_cell->name] = mux_cell;
 
 	mux_cell->parameters["\\WIDTH"] = RTLIL::Const(when_signal.size());
 	mux_cell->connections["\\A"] = else_signal;
diff --git a/passes/sat/expose.cc b/passes/sat/expose.cc
index c9363f4bf..29ce899ef 100644
--- a/passes/sat/expose.cc
+++ b/passes/sat/expose.cc
@@ -554,15 +554,12 @@ struct ExposePass : public Pass {
 				if (info.clk_polarity) {
 					module->connections.push_back(RTLIL::SigSig(wire_c, info.sig_clk));
 				} else {
-					RTLIL::Cell *c = new RTLIL::Cell;
-					c->name = NEW_ID;
-					c->type = "$not";
+					RTLIL::Cell *c = module->addCell(NEW_ID, "$not");
 					c->parameters["\\A_SIGNED"] = 0;
 					c->parameters["\\A_WIDTH"] = 1;
 					c->parameters["\\Y_WIDTH"] = 1;
 					c->connections["\\A"] = info.sig_clk;
 					c->connections["\\Y"] = wire_c;
-					module->add(c);
 				}
 
 				if (info.sig_arst != RTLIL::State::Sm)
@@ -575,15 +572,12 @@ struct ExposePass : public Pass {
 					if (info.arst_polarity) {
 						module->connections.push_back(RTLIL::SigSig(wire_r, info.sig_arst));
 					} else {
-						RTLIL::Cell *c = new RTLIL::Cell;
-						c->name = NEW_ID;
-						c->type = "$not";
+						RTLIL::Cell *c = module->addCell(NEW_ID, "$not");
 						c->parameters["\\A_SIGNED"] = 0;
 						c->parameters["\\A_WIDTH"] = 1;
 						c->parameters["\\Y_WIDTH"] = 1;
 						c->connections["\\A"] = info.sig_arst;
 						c->connections["\\Y"] = wire_r;
-						module->add(c);
 					}
 
 					RTLIL::Wire *wire_v = new RTLIL::Wire;
@@ -598,7 +592,7 @@ struct ExposePass : public Pass {
 
 			if (flag_evert)
 			{
-				std::vector<std::string> delete_cells;
+				std::vector<RTLIL::Cell*> delete_cells;
 
 				for (auto &it : module->cells)
 				{
@@ -665,13 +659,12 @@ struct ExposePass : public Pass {
 						}
 					}
 
-					delete_cells.push_back(cell->name);
+					delete_cells.push_back(cell);
 				}
 
-				for (auto &it : delete_cells) {
-					log("Removing cell: %s/%s (%s)\n", RTLIL::id2cstr(module->name), RTLIL::id2cstr(it), RTLIL::id2cstr(module->cells.at(it)->type));
-					delete module->cells.at(it);
-					module->cells.erase(it);
+				for (auto cell : delete_cells) {
+					log("Removing cell: %s/%s (%s)\n", log_id(module), log_id(cell), log_id(cell->type));
+					module->remove(cell);
 				}
 			}
 
diff --git a/passes/sat/freduce.cc b/passes/sat/freduce.cc
index ba01bc322..79dec3b54 100644
--- a/passes/sat/freduce.cc
+++ b/passes/sat/freduce.cc
@@ -718,12 +718,9 @@ struct FreduceWorker
 					{
 						inv_sig = module->addWire(NEW_ID);
 
-						RTLIL::Cell *inv_cell = new RTLIL::Cell;
-						inv_cell->name = NEW_ID;
-						inv_cell->type = "$_INV_";
+						RTLIL::Cell *inv_cell = module->addCell(NEW_ID, "$_INV_");
 						inv_cell->connections["\\A"] = grp[0].bit;
 						inv_cell->connections["\\Y"] = inv_sig;
-						module->add(inv_cell);
 					}
 
 					module->connections.push_back(RTLIL::SigSig(grp[i].bit, inv_sig));
diff --git a/passes/sat/miter.cc b/passes/sat/miter.cc
index 12384e2cc..aff664242 100644
--- a/passes/sat/miter.cc
+++ b/passes/sat/miter.cc
@@ -115,15 +115,8 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 	miter_module->name = miter_name;
 	design->modules[miter_name] = miter_module;
 
-	RTLIL::Cell *gold_cell = new RTLIL::Cell;
-	gold_cell->name = "\\gold";
-	gold_cell->type = gold_name;
-	miter_module->add(gold_cell);
-
-	RTLIL::Cell *gate_cell = new RTLIL::Cell;
-	gate_cell->name = "\\gate";
-	gate_cell->type = gate_name;
-	miter_module->add(gate_cell);
+	RTLIL::Cell *gold_cell = miter_module->addCell("\\gold", gold_name);
+	RTLIL::Cell *gate_cell = miter_module->addCell("\\gate", gate_name);
 
 	RTLIL::SigSpec all_conditions;
 
@@ -166,9 +159,7 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 			{
 				RTLIL::SigSpec gold_x = miter_module->addWire(NEW_ID, w2_gold->width);
 				for (int i = 0; i < w2_gold->width; i++) {
-					RTLIL::Cell *eqx_cell = new RTLIL::Cell;
-					eqx_cell->name = NEW_ID;
-					eqx_cell->type = "$eqx";
+					RTLIL::Cell *eqx_cell = miter_module->addCell(NEW_ID, "$eqx");
 					eqx_cell->parameters["\\A_WIDTH"] = 1;
 					eqx_cell->parameters["\\B_WIDTH"] = 1;
 					eqx_cell->parameters["\\Y_WIDTH"] = 1;
@@ -177,15 +168,12 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 					eqx_cell->connections["\\A"] = RTLIL::SigSpec(w2_gold, i);
 					eqx_cell->connections["\\B"] = RTLIL::State::Sx;
 					eqx_cell->connections["\\Y"] = gold_x.extract(i, 1);
-					miter_module->add(eqx_cell);
 				}
 
 				RTLIL::SigSpec gold_masked = miter_module->addWire(NEW_ID, w2_gold->width);
 				RTLIL::SigSpec gate_masked = miter_module->addWire(NEW_ID, w2_gate->width);
 
-				RTLIL::Cell *or_gold_cell = new RTLIL::Cell;
-				or_gold_cell->name = NEW_ID;
-				or_gold_cell->type = "$or";
+				RTLIL::Cell *or_gold_cell = miter_module->addCell(NEW_ID, "$or");
 				or_gold_cell->parameters["\\A_WIDTH"] = w2_gold->width;
 				or_gold_cell->parameters["\\B_WIDTH"] = w2_gold->width;
 				or_gold_cell->parameters["\\Y_WIDTH"] = w2_gold->width;
@@ -194,11 +182,8 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 				or_gold_cell->connections["\\A"] = w2_gold;
 				or_gold_cell->connections["\\B"] = gold_x;
 				or_gold_cell->connections["\\Y"] = gold_masked;
-				miter_module->add(or_gold_cell);
 
-				RTLIL::Cell *or_gate_cell = new RTLIL::Cell;
-				or_gate_cell->name = NEW_ID;
-				or_gate_cell->type = "$or";
+				RTLIL::Cell *or_gate_cell = miter_module->addCell(NEW_ID, "$or");
 				or_gate_cell->parameters["\\A_WIDTH"] = w2_gate->width;
 				or_gate_cell->parameters["\\B_WIDTH"] = w2_gate->width;
 				or_gate_cell->parameters["\\Y_WIDTH"] = w2_gate->width;
@@ -207,11 +192,8 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 				or_gate_cell->connections["\\A"] = w2_gate;
 				or_gate_cell->connections["\\B"] = gold_x;
 				or_gate_cell->connections["\\Y"] = gate_masked;
-				miter_module->add(or_gate_cell);
 
-				RTLIL::Cell *eq_cell = new RTLIL::Cell;
-				eq_cell->name = NEW_ID;
-				eq_cell->type = "$eqx";
+				RTLIL::Cell *eq_cell = miter_module->addCell(NEW_ID, "$eqx");
 				eq_cell->parameters["\\A_WIDTH"] = w2_gold->width;
 				eq_cell->parameters["\\B_WIDTH"] = w2_gate->width;
 				eq_cell->parameters["\\Y_WIDTH"] = 1;
@@ -221,13 +203,10 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 				eq_cell->connections["\\B"] = gate_masked;
 				eq_cell->connections["\\Y"] = miter_module->addWire(NEW_ID);
 				this_condition = eq_cell->connections["\\Y"];
-				miter_module->add(eq_cell);
 			}
 			else
 			{
-				RTLIL::Cell *eq_cell = new RTLIL::Cell;
-				eq_cell->name = NEW_ID;
-				eq_cell->type = "$eqx";
+				RTLIL::Cell *eq_cell = miter_module->addCell(NEW_ID, "$eqx");
 				eq_cell->parameters["\\A_WIDTH"] = w2_gold->width;
 				eq_cell->parameters["\\B_WIDTH"] = w2_gate->width;
 				eq_cell->parameters["\\Y_WIDTH"] = 1;
@@ -237,7 +216,6 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 				eq_cell->connections["\\B"] = w2_gate;
 				eq_cell->connections["\\Y"] = miter_module->addWire(NEW_ID);
 				this_condition = eq_cell->connections["\\Y"];
-				miter_module->add(eq_cell);
 			}
 
 			if (flag_make_outcmp)
@@ -254,25 +232,19 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 	}
 
 	if (all_conditions.size() != 1) {
-		RTLIL::Cell *reduce_cell = new RTLIL::Cell;
-		reduce_cell->name = NEW_ID;
-		reduce_cell->type = "$reduce_and";
+		RTLIL::Cell *reduce_cell = miter_module->addCell(NEW_ID, "$reduce_and");
 		reduce_cell->parameters["\\A_WIDTH"] = all_conditions.size();
 		reduce_cell->parameters["\\Y_WIDTH"] = 1;
 		reduce_cell->parameters["\\A_SIGNED"] = 0;
 		reduce_cell->connections["\\A"] = all_conditions;
 		reduce_cell->connections["\\Y"] = miter_module->addWire(NEW_ID);
 		all_conditions = reduce_cell->connections["\\Y"];
-		miter_module->add(reduce_cell);
 	}
 
 	if (flag_make_assert) {
-		RTLIL::Cell *assert_cell = new RTLIL::Cell;
-		assert_cell->name = NEW_ID;
-		assert_cell->type = "$assert";
+		RTLIL::Cell *assert_cell = miter_module->addCell(NEW_ID, "$assert");
 		assert_cell->connections["\\A"] = all_conditions;
 		assert_cell->connections["\\EN"] = RTLIL::SigSpec(1, 1);
-		miter_module->add(assert_cell);
 	}
 
 	RTLIL::Wire *w_trigger = new RTLIL::Wire;
@@ -280,16 +252,13 @@ static void create_miter_equiv(struct Pass *that, std::vector<std::string> args,
 	w_trigger->port_output = true;
 	miter_module->add(w_trigger);
 
-	RTLIL::Cell *not_cell = new RTLIL::Cell;
-	not_cell->name = NEW_ID;
-	not_cell->type = "$not";
+	RTLIL::Cell *not_cell = miter_module->addCell(NEW_ID, "$not");
 	not_cell->parameters["\\A_WIDTH"] = all_conditions.size();
 	not_cell->parameters["\\A_WIDTH"] = all_conditions.size();
 	not_cell->parameters["\\Y_WIDTH"] = w_trigger->width;
 	not_cell->parameters["\\A_SIGNED"] = 0;
 	not_cell->connections["\\A"] = all_conditions;
 	not_cell->connections["\\Y"] = w_trigger;
-	miter_module->add(not_cell);
 
 	miter_module->fixup_ports();
 
diff --git a/passes/sat/share.cc b/passes/sat/share.cc
index ede2fa88c..7e24e1f04 100644
--- a/passes/sat/share.cc
+++ b/passes/sat/share.cc
@@ -282,15 +282,12 @@ struct ShareWorker
 			RTLIL::SigSpec a = module->Mux(NEW_ID, a2, a1, act);
 			RTLIL::Wire *y = module->addWire(NEW_ID, y_width);
 
-			RTLIL::Cell *supercell = new RTLIL::Cell;
-			supercell->name = NEW_ID;
-			supercell->type = c1->type;
+			RTLIL::Cell *supercell = module->addCell(NEW_ID, c1->type);
 			supercell->parameters["\\A_SIGNED"] = a_signed;
 			supercell->parameters["\\A_WIDTH"] = a_width;
 			supercell->parameters["\\Y_WIDTH"] = y_width;
 			supercell->connections["\\A"] = a;
 			supercell->connections["\\Y"] = y;
-			module->add(supercell);
 
 			RTLIL::SigSpec new_y1(y, 0, y1.size());
 			RTLIL::SigSpec new_y2(y, 0, y2.size());
@@ -846,8 +843,7 @@ struct ShareWorker
 			log("Removing %d cells in module %s:\n", SIZE(cells_to_remove), log_id(module));
 			for (auto c : cells_to_remove) {
 				log("  Removing cell %s (%s).\n", log_id(c), log_id(c->type));
-				module->cells.erase(c->name);
-				delete c;
+				module->remove(c);
 			}
 		}
 
diff --git a/passes/techmap/dfflibmap.cc b/passes/techmap/dfflibmap.cc
index 4bf73358b..c047e418a 100644
--- a/passes/techmap/dfflibmap.cc
+++ b/passes/techmap/dfflibmap.cc
@@ -394,28 +394,24 @@ static void dfflibmap(RTLIL::Design *design, RTLIL::Module *module)
 	}
 
 	std::map<std::string, int> stats;
-	for (auto cell : cell_list) {
-		cell_mapping &cm = cell_mappings[cell->type];
-		RTLIL::Cell *new_cell = new RTLIL::Cell;
-		new_cell->name = cell->name;
-		new_cell->type = "\\" + cm.cell_name;
+	for (auto cell : cell_list)
+	{
+		auto cell_type = cell->type;
+		auto cell_name = cell->name;
+		auto cell_connections = cell->connections;
+		module->remove(cell);
+
+		cell_mapping &cm = cell_mappings[cell_type];
+		RTLIL::Cell *new_cell = module->addCell(cell_name, "\\" + cm.cell_name);
+
 		for (auto &port : cm.ports) {
 			RTLIL::SigSpec sig;
 			if ('A' <= port.second && port.second <= 'Z') {
-				sig = cell->connections[std::string("\\") + port.second];
+				sig = cell_connections[std::string("\\") + port.second];
 			} else
 			if ('a' <= port.second && port.second <= 'z') {
-				sig = cell->connections[std::string("\\") + char(port.second - ('a' - 'A'))];
-				RTLIL::Cell *inv_cell = new RTLIL::Cell;
-				RTLIL::Wire *inv_wire = new RTLIL::Wire;
-				inv_cell->name = stringf("$dfflibmap$inv$%d", RTLIL::autoidx);
-				inv_wire->name = stringf("$dfflibmap$sig$%d", RTLIL::autoidx++);
-				inv_cell->type = "$_INV_";
-				inv_cell->connections[port.second == 'q' ? "\\Y" : "\\A"] = sig;
-				sig = RTLIL::SigSpec(inv_wire);
-				inv_cell->connections[port.second == 'q' ? "\\A" : "\\Y"] = sig;
-				module->cells[inv_cell->name] = inv_cell;
-				module->wires[inv_wire->name] = inv_wire;
+				sig = cell_connections[std::string("\\") + char(port.second - ('a' - 'A'))];
+				sig = module->InvGate(NEW_ID, sig);
 			} else
 			if (port.second == '0' || port.second == '1') {
 				sig = RTLIL::SigSpec(port.second == '0' ? 0 : 1, 1);
@@ -424,9 +420,8 @@ static void dfflibmap(RTLIL::Design *design, RTLIL::Module *module)
 				log_abort();
 			new_cell->connections["\\" + port.first] = sig;
 		}
-		stats[stringf("  mapped %%d %s cells to %s cells.\n", cell->type.c_str(), new_cell->type.c_str())]++;
-		module->cells[cell->name] = new_cell;
-		delete cell;
+
+		stats[stringf("  mapped %%d %s cells to %s cells.\n", cell_type.c_str(), new_cell->type.c_str())]++;
 	}
 
 	for (auto &stat: stats)
diff --git a/passes/techmap/extract.cc b/passes/techmap/extract.cc
index 4c3aec31d..e52c8fe52 100644
--- a/passes/techmap/extract.cc
+++ b/passes/techmap/extract.cc
@@ -297,10 +297,7 @@ namespace
 		SigSet<std::pair<std::string, int>> sig2port;
 
 		// create new cell
-		RTLIL::Cell *cell = new RTLIL::Cell;
-		cell->name = stringf("$extract$%s$%d", needle->name.c_str(), RTLIL::autoidx++);
-		cell->type = needle->name;
-		haystack->add(cell);
+		RTLIL::Cell *cell = haystack->addCell(stringf("$extract$%s$%d", needle->name.c_str(), RTLIL::autoidx++), needle->name);
 
 		// create cell ports
 		for (auto &it : needle->wires) {
@@ -333,8 +330,7 @@ namespace
 				}
 			}
 
-			haystack->cells.erase(haystack_cell->name);
-			delete haystack_cell;
+			haystack->remove(haystack_cell);
 		}
 
 		return cell;
@@ -741,9 +737,7 @@ struct ExtractPass : public Pass {
 				}
 
 				for (auto cell : cells) {
-					RTLIL::Cell *newCell = new RTLIL::Cell;
-					newCell->name = cell->name;
-					newCell->type = cell->type;
+					RTLIL::Cell *newCell = newMod->addCell(cell->name, cell->type);
 					newCell->parameters = cell->parameters;
 					for (auto &conn : cell->connections) {
 						std::vector<RTLIL::SigChunk> chunks = sigmap(conn.second);
@@ -752,7 +746,6 @@ struct ExtractPass : public Pass {
 								chunk.wire = newMod->wires.at(chunk.wire->name);
 						newCell->connections[conn.first] = chunks;
 					}
-					newMod->add(newCell);
 				}
 			}
 
diff --git a/passes/techmap/hilomap.cc b/passes/techmap/hilomap.cc
index 51b8802c4..e41536707 100644
--- a/passes/techmap/hilomap.cc
+++ b/passes/techmap/hilomap.cc
@@ -34,22 +34,16 @@ void hilomap_worker(RTLIL::SigSpec &sig)
 		if (bit == RTLIL::State::S1 && !hicell_celltype.empty()) {
 			if (!singleton_mode || last_hi == RTLIL::State::Sm) {
 				last_hi = module->addWire(NEW_ID);
-				RTLIL::Cell *cell = new RTLIL::Cell;
-				cell->name = NEW_ID;
-				cell->type = RTLIL::escape_id(hicell_celltype);
+				RTLIL::Cell *cell = module->addCell(NEW_ID, RTLIL::escape_id(hicell_celltype));
 				cell->connections[RTLIL::escape_id(hicell_portname)] = last_hi;
-				module->add(cell);
 			}
 			bit = last_hi;
 		}
 		if (bit == RTLIL::State::S0 && !locell_celltype.empty()) {
 			if (!singleton_mode || last_lo == RTLIL::State::Sm) {
 				last_lo = module->addWire(NEW_ID);
-				RTLIL::Cell *cell = new RTLIL::Cell;
-				cell->name = NEW_ID;
-				cell->type = RTLIL::escape_id(locell_celltype);
+				RTLIL::Cell *cell = module->addCell(NEW_ID, RTLIL::escape_id(locell_celltype));
 				cell->connections[RTLIL::escape_id(locell_portname)] = last_lo;
-				module->add(cell);
 			}
 			bit = last_lo;
 		}
diff --git a/passes/techmap/iopadmap.cc b/passes/techmap/iopadmap.cc
index 09147383a..7b2484d84 100644
--- a/passes/techmap/iopadmap.cc
+++ b/passes/techmap/iopadmap.cc
@@ -176,9 +176,7 @@ struct IopadmapPass : public Pass {
 				{
 					for (int i = 0; i < wire->width; i++)
 					{
-						RTLIL::Cell *cell = new RTLIL::Cell;
-						cell->name = NEW_ID;
-						cell->type = RTLIL::escape_id(celltype);
+						RTLIL::Cell *cell = module->addCell(NEW_ID, RTLIL::escape_id(celltype));
 						cell->connections[RTLIL::escape_id(portname)] = RTLIL::SigSpec(wire, i);
 						if (!portname2.empty())
 							cell->connections[RTLIL::escape_id(portname2)] = RTLIL::SigSpec(new_wire, i);
@@ -187,14 +185,11 @@ struct IopadmapPass : public Pass {
 						if (!nameparam.empty())
 							cell->parameters[RTLIL::escape_id(nameparam)] = RTLIL::Const(stringf("%s[%d]", RTLIL::id2cstr(wire->name), i));
 						cell->attributes["\\keep"] = RTLIL::Const(1);
-						module->add(cell);
 					}
 				}
 				else
 				{
-					RTLIL::Cell *cell = new RTLIL::Cell;
-					cell->name = NEW_ID;
-					cell->type = RTLIL::escape_id(celltype);
+					RTLIL::Cell *cell = module->addCell(NEW_ID, RTLIL::escape_id(celltype));
 					cell->connections[RTLIL::escape_id(portname)] = RTLIL::SigSpec(wire);
 					if (!portname2.empty())
 						cell->connections[RTLIL::escape_id(portname2)] = RTLIL::SigSpec(new_wire);
@@ -203,7 +198,6 @@ struct IopadmapPass : public Pass {
 					if (!nameparam.empty())
 						cell->parameters[RTLIL::escape_id(nameparam)] = RTLIL::Const(RTLIL::id2cstr(wire->name));
 					cell->attributes["\\keep"] = RTLIL::Const(1);
-					module->add(cell);
 				}
 
 				wire->port_id = 0;
diff --git a/passes/techmap/simplemap.cc b/passes/techmap/simplemap.cc
index 034677d3b..8489e7fd9 100644
--- a/passes/techmap/simplemap.cc
+++ b/passes/techmap/simplemap.cc
@@ -35,12 +35,9 @@ static void simplemap_not(RTLIL::Module *module, RTLIL::Cell *cell)
 	sig_a.extend(SIZE(sig_y), cell->parameters.at("\\A_SIGNED").as_bool());
 
 	for (int i = 0; i < SIZE(sig_y); i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = "$_INV_";
+		RTLIL::Cell *gate = module->addCell(NEW_ID, "$_INV_");
 		gate->connections["\\A"] = sig_a[i];
 		gate->connections["\\Y"] = sig_y[i];
-		module->add(gate);
 	}
 }
 
@@ -78,12 +75,9 @@ static void simplemap_bitop(RTLIL::Module *module, RTLIL::Cell *cell)
 		RTLIL::SigSpec sig_t = module->addWire(NEW_ID, SIZE(sig_y));
 
 		for (int i = 0; i < SIZE(sig_y); i++) {
-			RTLIL::Cell *gate = new RTLIL::Cell;
-			gate->name = NEW_ID;
-			gate->type = "$_INV_";
+			RTLIL::Cell *gate = module->addCell(NEW_ID, "$_INV_");
 			gate->connections["\\A"] = sig_t[i];
 			gate->connections["\\Y"] = sig_y[i];
-			module->add(gate);
 		}
 
 		sig_y = sig_t;
@@ -97,13 +91,10 @@ static void simplemap_bitop(RTLIL::Module *module, RTLIL::Cell *cell)
 	log_assert(!gate_type.empty());
 
 	for (int i = 0; i < SIZE(sig_y); i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = gate_type;
+		RTLIL::Cell *gate = module->addCell(NEW_ID, gate_type);
 		gate->connections["\\A"] = sig_a[i];
 		gate->connections["\\B"] = sig_b[i];
 		gate->connections["\\Y"] = sig_y[i];
-		module->add(gate);
 	}
 }
 
@@ -150,14 +141,11 @@ static void simplemap_reduce(RTLIL::Module *module, RTLIL::Cell *cell)
 				continue;
 			}
 
-			RTLIL::Cell *gate = new RTLIL::Cell;
-			gate->name = NEW_ID;
-			gate->type = gate_type;
+			RTLIL::Cell *gate = module->addCell(NEW_ID, gate_type);
 			gate->connections["\\A"] = sig_a[i];
 			gate->connections["\\B"] = sig_a[i+1];
 			gate->connections["\\Y"] = sig_t[i/2];
 			last_output = &gate->connections["\\Y"];
-			module->add(gate);
 		}
 
 		sig_a = sig_t;
@@ -165,13 +153,10 @@ static void simplemap_reduce(RTLIL::Module *module, RTLIL::Cell *cell)
 
 	if (cell->type == "$reduce_xnor") {
 		RTLIL::SigSpec sig_t = module->addWire(NEW_ID);
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = "$_INV_";
+		RTLIL::Cell *gate = module->addCell(NEW_ID, "$_INV_");
 		gate->connections["\\A"] = sig_a;
 		gate->connections["\\Y"] = sig_t;
 		last_output = &gate->connections["\\Y"];
-		module->add(gate);
 		sig_a = sig_t;
 	}
 
@@ -195,13 +180,10 @@ static void logic_reduce(RTLIL::Module *module, RTLIL::SigSpec &sig)
 				continue;
 			}
 
-			RTLIL::Cell *gate = new RTLIL::Cell;
-			gate->name = NEW_ID;
-			gate->type = "$_OR_";
+			RTLIL::Cell *gate = module->addCell(NEW_ID, "$_OR_");
 			gate->connections["\\A"] = sig[i];
 			gate->connections["\\B"] = sig[i+1];
 			gate->connections["\\Y"] = sig_t[i/2];
-			module->add(gate);
 		}
 
 		sig = sig_t;
@@ -226,12 +208,9 @@ static void simplemap_lognot(RTLIL::Module *module, RTLIL::Cell *cell)
 		sig_y = sig_y.extract(0, 1);
 	}
 
-	RTLIL::Cell *gate = new RTLIL::Cell;
-	gate->name = NEW_ID;
-	gate->type = "$_INV_";
+	RTLIL::Cell *gate = module->addCell(NEW_ID, "$_INV_");
 	gate->connections["\\A"] = sig_a;
 	gate->connections["\\Y"] = sig_y;
-	module->add(gate);
 }
 
 static void simplemap_logbin(RTLIL::Module *module, RTLIL::Cell *cell)
@@ -257,13 +236,10 @@ static void simplemap_logbin(RTLIL::Module *module, RTLIL::Cell *cell)
 	if (cell->type == "$logic_or")  gate_type = "$_OR_";
 	log_assert(!gate_type.empty());
 
-	RTLIL::Cell *gate = new RTLIL::Cell;
-	gate->name = NEW_ID;
-	gate->type = gate_type;
+	RTLIL::Cell *gate = module->addCell(NEW_ID, gate_type);
 	gate->connections["\\A"] = sig_a;
 	gate->connections["\\B"] = sig_b;
 	gate->connections["\\Y"] = sig_y;
-	module->add(gate);
 }
 
 static void simplemap_mux(RTLIL::Module *module, RTLIL::Cell *cell)
@@ -273,14 +249,11 @@ static void simplemap_mux(RTLIL::Module *module, RTLIL::Cell *cell)
 	RTLIL::SigSpec sig_y = cell->connections.at("\\Y");
 
 	for (int i = 0; i < SIZE(sig_y); i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = "$_MUX_";
+		RTLIL::Cell *gate = module->addCell(NEW_ID, "$_MUX_");
 		gate->connections["\\A"] = sig_a[i];
 		gate->connections["\\B"] = sig_b[i];
 		gate->connections["\\S"] = cell->connections.at("\\S");
 		gate->connections["\\Y"] = sig_y[i];
-		module->add(gate);
 	}
 }
 
@@ -313,13 +286,10 @@ static void simplemap_sr(RTLIL::Module *module, RTLIL::Cell *cell)
 	std::string gate_type = stringf("$_SR_%c%c_", set_pol, clr_pol);
 
 	for (int i = 0; i < width; i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = gate_type;
+		RTLIL::Cell *gate = module->addCell(NEW_ID, gate_type);
 		gate->connections["\\S"] = sig_s[i];
 		gate->connections["\\R"] = sig_r[i];
 		gate->connections["\\Q"] = sig_q[i];
-		module->add(gate);
 	}
 }
 
@@ -335,13 +305,10 @@ static void simplemap_dff(RTLIL::Module *module, RTLIL::Cell *cell)
 	std::string gate_type = stringf("$_DFF_%c_", clk_pol);
 
 	for (int i = 0; i < width; i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = gate_type;
+		RTLIL::Cell *gate = module->addCell(NEW_ID, gate_type);
 		gate->connections["\\C"] = sig_clk;
 		gate->connections["\\D"] = sig_d[i];
 		gate->connections["\\Q"] = sig_q[i];
-		module->add(gate);
 	}
 }
 
@@ -361,15 +328,12 @@ static void simplemap_dffsr(RTLIL::Module *module, RTLIL::Cell *cell)
 	std::string gate_type = stringf("$_DFFSR_%c%c%c_", clk_pol, set_pol, clr_pol);
 
 	for (int i = 0; i < width; i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = gate_type;
+		RTLIL::Cell *gate = module->addCell(NEW_ID, gate_type);
 		gate->connections["\\C"] = sig_clk;
 		gate->connections["\\S"] = sig_s[i];
 		gate->connections["\\R"] = sig_r[i];
 		gate->connections["\\D"] = sig_d[i];
 		gate->connections["\\Q"] = sig_q[i];
-		module->add(gate);
 	}
 }
 
@@ -392,14 +356,11 @@ static void simplemap_adff(RTLIL::Module *module, RTLIL::Cell *cell)
 	std::string gate_type_1 = stringf("$_DFF_%c%c1_", clk_pol, rst_pol);
 
 	for (int i = 0; i < width; i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = rst_val.at(i) == RTLIL::State::S1 ? gate_type_1 : gate_type_0;
+		RTLIL::Cell *gate = module->addCell(NEW_ID, rst_val.at(i) == RTLIL::State::S1 ? gate_type_1 : gate_type_0);
 		gate->connections["\\C"] = sig_clk;
 		gate->connections["\\R"] = sig_rst;
 		gate->connections["\\D"] = sig_d[i];
 		gate->connections["\\Q"] = sig_q[i];
-		module->add(gate);
 	}
 }
 
@@ -415,13 +376,10 @@ static void simplemap_dlatch(RTLIL::Module *module, RTLIL::Cell *cell)
 	std::string gate_type = stringf("$_DLATCH_%c_", en_pol);
 
 	for (int i = 0; i < width; i++) {
-		RTLIL::Cell *gate = new RTLIL::Cell;
-		gate->name = NEW_ID;
-		gate->type = gate_type;
+		RTLIL::Cell *gate = module->addCell(NEW_ID, gate_type);
 		gate->connections["\\E"] = sig_en;
 		gate->connections["\\D"] = sig_d[i];
 		gate->connections["\\Q"] = sig_q[i];
-		module->add(gate);
 	}
 }
 
@@ -490,10 +448,8 @@ struct SimplemapPass : public Pass {
 				mappers.at(cell_it.second->type)(mod_it.second, cell_it.second);
 				delete_cells.push_back(cell_it.second);
 			}
-			for (auto &it : delete_cells) {
-				mod_it.second->cells.erase(it->name);
-				delete it;
-			}
+			for (auto c : delete_cells)
+				mod_it.second->remove(c);
 		}
 	}
 } SimplemapPass;
diff --git a/passes/techmap/techmap.cc b/passes/techmap/techmap.cc
index 8d7b21e0f..e8385844d 100644
--- a/passes/techmap/techmap.cc
+++ b/passes/techmap/techmap.cc
@@ -114,15 +114,12 @@ struct TechmapWorker
 			log_error("Technology map yielded processes -> this is not supported.\n");
 		}
 
-		// erase from namespace first for _TECHMAP_REPLACE_ to work
-		module->cells.erase(cell->name);
 		std::string orig_cell_name;
-
 		if (!flatten_mode)
 			for (auto &it : tpl->cells)
 				if (it.first == "\\_TECHMAP_REPLACE_") {
 					orig_cell_name = cell->name;
-					cell->name = stringf("$techmap%d", RTLIL::autoidx++) + cell->name;
+					module->rename(cell, stringf("$techmap%d", RTLIL::autoidx++) + cell->name);
 					break;
 				}
 
@@ -183,20 +180,29 @@ struct TechmapWorker
 			}
 		}
 
-		for (auto &it : tpl->cells) {
-			RTLIL::Cell *c = new RTLIL::Cell(*it.second);
-			if (!flatten_mode && c->type.substr(0, 2) == "\\$")
-				c->type = c->type.substr(1);
-			if (!flatten_mode && c->name == "\\_TECHMAP_REPLACE_")
-				c->name = orig_cell_name;
+		for (auto &it : tpl->cells)
+		{
+			RTLIL::IdString c_name = it.second->name;
+			RTLIL::IdString c_type = it.second->type;
+
+			if (!flatten_mode && c_type.substr(0, 2) == "\\$")
+				c_type = c_type.substr(1);
+
+			if (!flatten_mode && c_name == "\\_TECHMAP_REPLACE_")
+				c_name = orig_cell_name;
 			else
-				apply_prefix(cell->name, c->name);
+				apply_prefix(cell->name, c_name);
+
+			RTLIL::Cell *c = module->addCell(c_name, c_type);
+			c->connections = it.second->connections;
+			c->parameters = it.second->parameters;
+			c->attributes = it.second->attributes;
+			design->select(module, c);
+
 			for (auto &it2 : c->connections) {
 				apply_prefix(cell->name, it2.second, module);
 				port_signal_map.apply(it2.second);
 			}
-			module->add(c);
-			design->select(module, c);
 		}
 
 		for (auto &it : tpl->connections) {
@@ -208,7 +214,7 @@ struct TechmapWorker
 			module->connections.push_back(c);
 		}
 
-		delete cell;
+		module->remove(cell);
 	}
 
 	bool techmap_module(RTLIL::Design *design, RTLIL::Module *module, RTLIL::Design *map, std::set<RTLIL::Cell*> &handled_cells,
@@ -254,8 +260,7 @@ struct TechmapWorker
 						if (simplemap_mappers.count(cell->type) == 0)
 							log_error("No simplemap mapper for cell type %s found!\n", RTLIL::id2cstr(cell->type));
 						simplemap_mappers.at(cell->type)(module, cell);
-						module->cells.erase(cell->name);
-						delete cell;
+						module->remove(cell);
 						cell = NULL;
 						did_something = true;
 						break;