Merge remote-tracking branch 'origin/master' into xc7mux

17 files changed, 384 insertions, 139 deletions

diff --git a/passes/cmds/bugpoint.cc b/passes/cmds/bugpoint.cc
index 4b22f6d2d..038ab7c7c 100644
--- a/passes/cmds/bugpoint.cc
+++ b/passes/cmds/bugpoint.cc
@@ -281,6 +281,9 @@ struct BugpointPass : public Pass {
 		}
 		extra_args(args, argidx, design);
 
+		if (script.empty())
+			log_cmd_error("Missing -script option.\n");
+
 		if (!has_part)
 		{
 			modules = true;
@@ -298,7 +301,7 @@ struct BugpointPass : public Pass {
 		if (!check_logfile(grep))
 			log_cmd_error("The provided grep string is not found in the log file!\n");
 
-		int seed = 0, crashing_seed = seed;
+		int seed = 0;
 		bool found_something = false, stage2 = false;
 		while (true)
 		{
@@ -324,7 +327,6 @@ struct BugpointPass : public Pass {
 					if (crashing_design != design)
 						delete crashing_design;
 					crashing_design = simplified;
-					crashing_seed = seed;
 					found_something = true;
 				}
 				else
diff --git a/passes/cmds/cover.cc b/passes/cmds/cover.cc
index 0ec747671..1128116b4 100644
--- a/passes/cmds/cover.cc
+++ b/passes/cmds/cover.cc
@@ -98,21 +98,23 @@ struct CoverPass : public Pass {
 			}
 			if ((args[argidx] == "-o" || args[argidx] == "-a" || args[argidx] == "-d") && argidx+1 < args.size()) {
 				const char *open_mode = args[argidx] == "-a" ? "a+" : "w";
-				std::string filename = args[++argidx];
+				const std::string &filename = args[++argidx];
+				FILE *f = nullptr;
 				if (args[argidx-1] == "-d") {
 			#ifdef _WIN32
 					log_cmd_error("The 'cover -d' option is not supported on win32.\n");
 			#else
 					char filename_buffer[4096];
 					snprintf(filename_buffer, 4096, "%s/yosys_cover_%d_XXXXXX.txt", filename.c_str(), getpid());
-					filename = mkstemps(filename_buffer, 4);
+					f = fdopen(mkstemps(filename_buffer, 4), "w");
 			#endif
+				} else {
+					f = fopen(filename.c_str(), open_mode);
 				}
-				FILE *f = fopen(filename.c_str(), open_mode);
 				if (f == NULL) {
 					for (auto f : out_files)
 						fclose(f);
-					log_cmd_error("Can't create file %s.\n", args[argidx].c_str());
+					log_cmd_error("Can't create file %s%s.\n", args[argidx-1] == "-d" ? "in directory " : "", args[argidx].c_str());
 				}
 				out_files.push_back(f);
 				continue;
diff --git a/passes/cmds/stat.cc b/passes/cmds/stat.cc
index 3909c4c8c..c42f7fcdd 100644
--- a/passes/cmds/stat.cc
+++ b/passes/cmds/stat.cc
@@ -37,7 +37,9 @@ struct statdata_t
 	STAT_INT_MEMBERS
 	#undef X
 	double area;
+	string tech;
 
+	std::map<RTLIL::IdString, int> techinfo;
 	std::map<RTLIL::IdString, int, RTLIL::sort_by_id_str> num_cells_by_type;
 	std::set<RTLIL::IdString> unknown_cell_area;
 
@@ -70,8 +72,10 @@ struct statdata_t
 	#undef X
 	}
 
-	statdata_t(RTLIL::Design *design, RTLIL::Module *mod, bool width_mode, const dict<IdString, double> &cell_area)
+	statdata_t(RTLIL::Design *design, RTLIL::Module *mod, bool width_mode, const dict<IdString, double> &cell_area, string techname)
 	{
+		tech = techname;
+
 	#define X(_name) _name = 0;
 		STAT_NUMERIC_MEMBERS
 	#undef X
@@ -153,7 +157,8 @@ struct statdata_t
 		log("   Number of processes:         %6d\n", num_processes);
 		log("   Number of cells:             %6d\n", num_cells);
 		for (auto &it : num_cells_by_type)
-			log("     %-26s %6d\n", RTLIL::id2cstr(it.first), it.second);
+			if (it.second)
+				log("     %-26s %6d\n", RTLIL::id2cstr(it.first), it.second);
 
 		if (!unknown_cell_area.empty()) {
 			log("\n");
@@ -165,6 +170,59 @@ struct statdata_t
 			log("\n");
 			log("   Chip area for %smodule '%s': %f\n", (top_mod) ? "top " : "", mod_name.c_str(), area);
 		}
+
+		if (tech == "xilinx")
+		{
+			int lut6_cnt = num_cells_by_type["\\LUT6"];
+			int lut5_cnt = num_cells_by_type["\\LUT5"];
+			int lut4_cnt = num_cells_by_type["\\LUT4"];
+			int lut3_cnt = num_cells_by_type["\\LUT3"];
+			int lut2_cnt = num_cells_by_type["\\LUT2"];
+			int lut1_cnt = num_cells_by_type["\\LUT1"];
+			int lc_cnt = 0;
+
+			lc_cnt += lut6_cnt;
+
+			lc_cnt += lut5_cnt;
+			if (lut1_cnt) {
+				int cnt = std::min(lut5_cnt, lut1_cnt);
+				lut5_cnt -= cnt;
+				lut1_cnt -= cnt;
+			}
+
+			lc_cnt += lut4_cnt;
+			if (lut1_cnt) {
+				int cnt = std::min(lut4_cnt, lut1_cnt);
+				lut4_cnt -= cnt;
+				lut1_cnt -= cnt;
+			}
+			if (lut2_cnt) {
+				int cnt = std::min(lut4_cnt, lut2_cnt);
+				lut4_cnt -= cnt;
+				lut2_cnt -= cnt;
+			}
+
+			lc_cnt += lut3_cnt;
+			if (lut1_cnt) {
+				int cnt = std::min(lut3_cnt, lut1_cnt);
+				lut3_cnt -= cnt;
+				lut1_cnt -= cnt;
+			}
+			if (lut2_cnt) {
+				int cnt = std::min(lut3_cnt, lut2_cnt);
+				lut3_cnt -= cnt;
+				lut2_cnt -= cnt;
+			}
+			if (lut3_cnt) {
+				int cnt = (lut3_cnt + 1) / 2;
+				lut3_cnt -= cnt;
+			}
+
+			lc_cnt += (lut2_cnt + lut1_cnt + 1) / 2;
+
+			log("\n");
+			log("   Estimated number of LCs: %10d\n", lc_cnt);
+		}
 	}
 };
 
@@ -226,6 +284,10 @@ struct StatPass : public Pass {
 		log("    -liberty <liberty_file>\n");
 		log("        use cell area information from the provided liberty file\n");
 		log("\n");
+		log("    -tech <technology>\n");
+		log("        print area estemate for the specified technology. Corrently supported\n");
+		log("        calues for <technology>: xilinx\n");
+		log("\n");
 		log("    -width\n");
 		log("        annotate internal cell types with their word width.\n");
 		log("        e.g. $add_8 for an 8 bit wide $add cell.\n");
@@ -239,6 +301,7 @@ struct StatPass : public Pass {
 		RTLIL::Module *top_mod = NULL;
 		std::map<RTLIL::IdString, statdata_t> mod_stat;
 		dict<IdString, double> cell_area;
+		string techname;
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
@@ -253,6 +316,10 @@ struct StatPass : public Pass {
 				read_liberty_cellarea(cell_area, liberty_file);
 				continue;
 			}
+			if (args[argidx] == "-tech" && argidx+1 < args.size()) {
+				techname = args[++argidx];
+				continue;
+			}
 			if (args[argidx] == "-top" && argidx+1 < args.size()) {
 				if (design->modules_.count(RTLIL::escape_id(args[argidx+1])) == 0)
 					log_cmd_error("Can't find module %s.\n", args[argidx+1].c_str());
@@ -263,6 +330,9 @@ struct StatPass : public Pass {
 		}
 		extra_args(args, argidx, design);
 
+		if (techname != "" && techname != "xilinx")
+			log_cmd_error("Unsupported technology: '%s'\n", techname.c_str());
+
 		for (auto mod : design->selected_modules())
 		{
 			if (!top_mod && design->full_selection())
@@ -272,7 +342,7 @@ struct StatPass : public Pass {
 			if (mod->attributes.count("\\abc_box_id"))
 				continue;
 
-			statdata_t data(design, mod, width_mode, cell_area);
+			statdata_t data(design, mod, width_mode, cell_area, techname);
 			mod_stat[mod->name] = data;
 
 			log("\n");
diff --git a/passes/hierarchy/hierarchy.cc b/passes/hierarchy/hierarchy.cc
index b8ff99884..72bc2e133 100644
--- a/passes/hierarchy/hierarchy.cc
+++ b/passes/hierarchy/hierarchy.cc
@@ -570,7 +570,7 @@ struct HierarchyPass : public Pass {
 		log("\n");
 		log("    -simcheck\n");
 		log("        like -check, but also throw an error if blackbox modules are\n");
-		log("        instantiated, and throw an error if the design has no top module\n");
+		log("        instantiated, and throw an error if the design has no top module.\n");
 		log("\n");
 		log("    -purge_lib\n");
 		log("        by default the hierarchy command will not remove library (blackbox)\n");
@@ -583,20 +583,20 @@ struct HierarchyPass : public Pass {
 		log("\n");
 		log("    -keep_positionals\n");
 		log("        per default this pass also converts positional arguments in cells\n");
-		log("        to arguments using port names. this option disables this behavior.\n");
+		log("        to arguments using port names. This option disables this behavior.\n");
 		log("\n");
 		log("    -keep_portwidths\n");
 		log("        per default this pass adjusts the port width on cells that are\n");
-		log("        module instances when the width does not match the module port. this\n");
+		log("        module instances when the width does not match the module port. This\n");
 		log("        option disables this behavior.\n");
 		log("\n");
 		log("    -nokeep_asserts\n");
 		log("        per default this pass sets the \"keep\" attribute on all modules\n");
-		log("        that directly or indirectly contain one or more $assert cells. this\n");
-		log("        option disables this behavior.\n");
+		log("        that directly or indirectly contain one or more formal properties.\n");
+		log("        This option disables this behavior.\n");
 		log("\n");
 		log("    -top <module>\n");
-		log("        use the specified top module to built a design hierarchy. modules\n");
+		log("        use the specified top module to build the design hierarchy. Modules\n");
 		log("        outside this tree (unused modules) are removed.\n");
 		log("\n");
 		log("        when the -top option is used, the 'top' attribute will be set on the\n");
@@ -606,6 +606,12 @@ struct HierarchyPass : public Pass {
 		log("    -auto-top\n");
 		log("        automatically determine the top of the design hierarchy and mark it.\n");
 		log("\n");
+		log("    -chparam name value \n");
+		log("       elaborate the top module using this parameter value. Modules on which\n");
+		log("       this parameter does not exist may cause a warning message to be output.\n");
+		log("       This option can be specified multiple times to override multiple\n");
+		log("       parameters. String values must be passed in double quotes (\").\n");
+		log("\n");
 		log("In -generate mode this pass generates blackbox modules for the given cell\n");
 		log("types (wildcards supported). For this the design is searched for cells that\n");
 		log("match the given types and then the given port declarations are used to\n");
@@ -641,6 +647,7 @@ struct HierarchyPass : public Pass {
 		bool nokeep_asserts = false;
 		std::vector<std::string> generate_cells;
 		std::vector<generate_port_decl_t> generate_ports;
+		std::map<std::string, std::string> parameters;
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
@@ -715,28 +722,61 @@ struct HierarchyPass : public Pass {
 			if (args[argidx] == "-top") {
 				if (++argidx >= args.size())
 					log_cmd_error("Option -top requires an additional argument!\n");
-				top_mod = design->modules_.count(RTLIL::escape_id(args[argidx])) ? design->modules_.at(RTLIL::escape_id(args[argidx])) : NULL;
-				if (top_mod == NULL && design->modules_.count("$abstract" + RTLIL::escape_id(args[argidx]))) {
-					dict<RTLIL::IdString, RTLIL::Const> empty_parameters;
-					design->modules_.at("$abstract" + RTLIL::escape_id(args[argidx]))->derive(design, empty_parameters);
-					top_mod = design->modules_.count(RTLIL::escape_id(args[argidx])) ? design->modules_.at(RTLIL::escape_id(args[argidx])) : NULL;
-				}
-				if (top_mod == NULL)
-					load_top_mod = args[argidx];
+				load_top_mod = args[argidx];
 				continue;
 			}
 			if (args[argidx] == "-auto-top") {
 				auto_top_mode = true;
 				continue;
 			}
+			if (args[argidx] == "-chparam"  && argidx+2 < args.size()) {
+				const std::string &key = args[++argidx];
+				const std::string &value = args[++argidx];
+				auto r = parameters.emplace(key, value);
+				if (!r.second) {
+					log_warning("-chparam %s already specified: overwriting.\n", key.c_str());
+					r.first->second = value;
+				}
+				continue;
+			}
 			break;
 		}
 		extra_args(args, argidx, design, false);
 
-		if (!load_top_mod.empty()) {
+		if (!load_top_mod.empty())
+		{
+			IdString top_name = RTLIL::escape_id(load_top_mod);
+			IdString abstract_id = "$abstract" + RTLIL::escape_id(load_top_mod);
+			top_mod = design->module(top_name);
+
+			dict<RTLIL::IdString, RTLIL::Const> top_parameters;
+			for (auto &para : parameters) {
+				SigSpec sig_value;
+				if (!RTLIL::SigSpec::parse(sig_value, NULL, para.second))
+					log_cmd_error("Can't decode value '%s'!\n", para.second.c_str());
+				top_parameters[RTLIL::escape_id(para.first)] = sig_value.as_const();
+			}
+
+			if (top_mod == nullptr && design->module(abstract_id))
+				top_mod = design->module(design->module(abstract_id)->derive(design, top_parameters));
+			else if (top_mod != nullptr && !top_parameters.empty())
+				top_mod = design->module(top_mod->derive(design, top_parameters));
+
+			if (top_mod != nullptr && top_mod->name != top_name) {
+				Module *m = top_mod->clone();
+				m->name = top_name;
+				Module *old_mod = design->module(top_name);
+				if (old_mod)
+					design->remove(old_mod);
+				design->add(m);
+				top_mod = m;
+			}
+		}
+
+		if (top_mod == nullptr && !load_top_mod.empty()) {
 #ifdef YOSYS_ENABLE_VERIFIC
 			if (verific_import_pending) {
-				verific_import(design, load_top_mod);
+				verific_import(design, parameters, load_top_mod);
 				top_mod = design->module(RTLIL::escape_id(load_top_mod));
 			}
 #endif
@@ -745,7 +785,7 @@ struct HierarchyPass : public Pass {
 		} else {
 #ifdef YOSYS_ENABLE_VERIFIC
 			if (verific_import_pending)
-				verific_import(design);
+				verific_import(design, parameters);
 #endif
 		}
 
@@ -846,7 +886,7 @@ struct HierarchyPass : public Pass {
 			std::map<RTLIL::Module*, bool> cache;
 			for (auto mod : design->modules())
 				if (set_keep_assert(cache, mod)) {
-					log("Module %s directly or indirectly contains $assert cells -> setting \"keep\" attribute.\n", log_id(mod));
+					log("Module %s directly or indirectly contains formal properties -> setting \"keep\" attribute.\n", log_id(mod));
 					mod->set_bool_attribute("\\keep");
 				}
 		}
diff --git a/passes/opt/opt_clean.cc b/passes/opt/opt_clean.cc
index 5d95c4f1a..bf8020169 100644
--- a/passes/opt/opt_clean.cc
+++ b/passes/opt/opt_clean.cc
@@ -64,7 +64,7 @@ struct keep_cache_t
 
 	bool query(Cell *cell)
 	{
-		if (cell->type.in("$memwr", "$meminit", "$assert", "$assume", "$live", "$fair", "$cover"))
+		if (cell->type.in("$memwr", "$meminit", "$assert", "$assume", "$live", "$fair", "$cover", "$specify2", "$specify3", "$specrule"))
 			return true;
 
 		if (cell->has_keep_attr())
@@ -85,22 +85,34 @@ void rmunused_module_cells(Module *module, bool verbose)
 {
 	SigMap sigmap(module);
 	pool<Cell*> queue, unused;
+	pool<SigBit> used_raw_bits;
 	dict<SigBit, pool<Cell*>> wire2driver;
+	dict<SigBit, vector<string>> driver_driver_logs;
+
+	SigMap raw_sigmap;
+	for (auto &it : module->connections_) {
+		for (int i = 0; i < GetSize(it.second); i++) {
+			if (it.second[i].wire != nullptr)
+				raw_sigmap.add(it.first[i], it.second[i]);
+		}
+	}
 
 	for (auto &it : module->cells_) {
 		Cell *cell = it.second;
 		for (auto &it2 : cell->connections()) {
-			if (!ct_all.cell_known(cell->type) || ct_all.cell_output(cell->type, it2.first))
-				for (auto raw_bit : it2.second) {
-					if (raw_bit.wire == nullptr)
-						continue;
-					auto bit = sigmap(raw_bit);
-					if (bit.wire == nullptr)
-						log_warning("Driver-driver conflict for %s between cell %s.%s and constant %s in %s: Resolved using constant.\n",
-								log_signal(raw_bit), log_id(cell), log_id(it2.first), log_signal(bit), log_id(module));
-					if (bit.wire != nullptr)
-						wire2driver[bit].insert(cell);
-				}
+			if (ct_all.cell_known(cell->type) && !ct_all.cell_output(cell->type, it2.first))
+				continue;
+			for (auto raw_bit : it2.second) {
+				if (raw_bit.wire == nullptr)
+					continue;
+				auto bit = sigmap(raw_bit);
+				if (bit.wire == nullptr)
+					driver_driver_logs[raw_sigmap(raw_bit)].push_back(stringf("Driver-driver conflict "
+							"for %s between cell %s.%s and constant %s in %s: Resolved using constant.",
+							log_signal(raw_bit), log_id(cell), log_id(it2.first), log_signal(bit), log_id(module)));
+				if (bit.wire != nullptr)
+					wire2driver[bit].insert(cell);
+			}
 		}
 		if (keep_cache.query(cell))
 			queue.insert(cell);
@@ -114,6 +126,8 @@ void rmunused_module_cells(Module *module, bool verbose)
 			for (auto bit : sigmap(wire))
 			for (auto c : wire2driver[bit])
 				queue.insert(c), unused.erase(c);
+			for (auto raw_bit : SigSpec(wire))
+				used_raw_bits.insert(raw_sigmap(raw_bit));
 		}
 	}
 
@@ -142,6 +156,22 @@ void rmunused_module_cells(Module *module, bool verbose)
 		module->remove(cell);
 		count_rm_cells++;
 	}
+
+	for (auto &it : module->cells_) {
+		Cell *cell = it.second;
+		for (auto &it2 : cell->connections()) {
+			if (ct_all.cell_known(cell->type) && !ct_all.cell_input(cell->type, it2.first))
+				continue;
+			for (auto raw_bit : raw_sigmap(it2.second))
+				used_raw_bits.insert(raw_bit);
+		}
+	}
+
+	for (auto it : driver_driver_logs) {
+		if (used_raw_bits.count(it.first))
+			for (auto msg : it.second)
+				log_warning("%s\n", msg.c_str());
+	}
 }
 
 int count_nontrivial_wire_attrs(RTLIL::Wire *w)
@@ -202,7 +232,7 @@ bool check_public_name(RTLIL::IdString id)
 	return true;
 }
 
-void rmunused_module_signals(RTLIL::Module *module, bool purge_mode, bool verbose)
+bool rmunused_module_signals(RTLIL::Module *module, bool purge_mode, bool verbose)
 {
 	SigPool register_signals;
 	SigPool connected_signals;
@@ -245,11 +275,13 @@ void rmunused_module_signals(RTLIL::Module *module, bool purge_mode, bool verbos
 	module->connections_.clear();
 
 	SigPool used_signals;
+	SigPool raw_used_signals;
 	SigPool used_signals_nodrivers;
 	for (auto &it : module->cells_) {
 		RTLIL::Cell *cell = it.second;
 		for (auto &it2 : cell->connections_) {
 			assign_map.apply(it2.second);
+			raw_used_signals.add(it2.second);
 			used_signals.add(it2.second);
 			if (!ct_all.cell_output(cell->type, it2.first))
 				used_signals_nodrivers.add(it2.second);
@@ -259,6 +291,7 @@ void rmunused_module_signals(RTLIL::Module *module, bool purge_mode, bool verbos
 		RTLIL::Wire *wire = it.second;
 		if (wire->port_id > 0) {
 			RTLIL::SigSpec sig = RTLIL::SigSpec(wire);
+			raw_used_signals.add(sig);
 			assign_map.apply(sig);
 			used_signals.add(sig);
 			if (!wire->port_input)
@@ -271,85 +304,102 @@ void rmunused_module_signals(RTLIL::Module *module, bool purge_mode, bool verbos
 		}
 	}
 
-	std::vector<RTLIL::Wire*> maybe_del_wires;
+	pool<RTLIL::Wire*> del_wires_queue;
 	for (auto wire : module->wires())
 	{
-		if ((!purge_mode && check_public_name(wire->name)) || wire->port_id != 0 || wire->get_bool_attribute("\\keep") || wire->attributes.count("\\init")) {
-			RTLIL::SigSpec s1 = RTLIL::SigSpec(wire), s2 = s1;
-			assign_map.apply(s2);
-			if (!used_signals.check_any(s2) && wire->port_id == 0 && !wire->get_bool_attribute("\\keep")) {
-				maybe_del_wires.push_back(wire);
-			} else {
-				log_assert(GetSize(s1) == GetSize(s2));
-				Const initval;
-				if (wire->attributes.count("\\init"))
-					initval = wire->attributes.at("\\init");
-				if (GetSize(initval) != GetSize(wire))
-					initval.bits.resize(GetSize(wire), State::Sx);
-				RTLIL::SigSig new_conn;
-				for (int i = 0; i < GetSize(s1); i++)
-					if (s1[i] != s2[i]) {
-						if (s2[i] == State::Sx && (initval[i] == State::S0 || initval[i] == State::S1)) {
-							s2[i] = initval[i];
-							initval[i] = State::Sx;
-						}
-						new_conn.first.append_bit(s1[i]);
-						new_conn.second.append_bit(s2[i]);
+		SigSpec s1 = SigSpec(wire), s2 = assign_map(s1);
+		log_assert(GetSize(s1) == GetSize(s2));
+
+		Const initval;
+		if (wire->attributes.count("\\init"))
+			initval = wire->attributes.at("\\init");
+		if (GetSize(initval) != GetSize(wire))
+			initval.bits.resize(GetSize(wire), State::Sx);
+		if (initval.is_fully_undef())
+			wire->attributes.erase("\\init");
+
+		if (GetSize(wire) == 0) {
+			// delete zero-width wires
+			goto delete_this_wire;
+		} else
+		if (wire->port_id != 0 || wire->get_bool_attribute("\\keep") || !initval.is_fully_undef()) {
+			// do not delete anything with "keep" or module ports or initialized wires
+		} else
+		if (!purge_mode && check_public_name(wire->name)) {
+			// do not get rid of public names unless in purge mode
+		} else
+		if (!raw_used_signals.check_any(s1)) {
+			// delete wires that aren't used by anything directly
+			goto delete_this_wire;
+		} else
+		if (!used_signals.check_any(s2)) {
+			// delete wires that aren't used by anything indirectly, even though other wires may alias it
+			goto delete_this_wire;
+		}
+
+		if (0)
+		{
+	delete_this_wire:
+			del_wires_queue.insert(wire);
+		}
+		else
+		{
+			RTLIL::SigSig new_conn;
+			for (int i = 0; i < GetSize(s1); i++)
+				if (s1[i] != s2[i]) {
+					if (s2[i] == State::Sx && (initval[i] == State::S0 || initval[i] == State::S1)) {
+						s2[i] = initval[i];
+						initval[i] = State::Sx;
 					}
-				if (new_conn.first.size() > 0) {
-					if (initval.is_fully_undef())
-						wire->attributes.erase("\\init");
-					else
-						wire->attributes.at("\\init") = initval;
-					used_signals.add(new_conn.first);
-					used_signals.add(new_conn.second);
-					module->connect(new_conn);
+					new_conn.first.append_bit(s1[i]);
+					new_conn.second.append_bit(s2[i]);
 				}
+			if (new_conn.first.size() > 0) {
+				if (initval.is_fully_undef())
+					wire->attributes.erase("\\init");
+				else
+					wire->attributes.at("\\init") = initval;
+				used_signals.add(new_conn.first);
+				used_signals.add(new_conn.second);
+				module->connect(new_conn);
 			}
-		} else {
-			if (!used_signals.check_any(RTLIL::SigSpec(wire)))
-				maybe_del_wires.push_back(wire);
-		}
 
-		RTLIL::SigSpec sig = assign_map(RTLIL::SigSpec(wire));
-		if (!used_signals_nodrivers.check_any(sig)) {
-			std::string unused_bits;
-			for (int i = 0; i < GetSize(sig); i++) {
-				if (sig[i].wire == NULL)
-					continue;
-				if (!used_signals_nodrivers.check(sig[i])) {
-					if (!unused_bits.empty())
-						unused_bits += " ";
-					unused_bits += stringf("%d", i);
+			if (!used_signals_nodrivers.check_all(s2)) {
+				std::string unused_bits;
+				for (int i = 0; i < GetSize(s2); i++) {
+					if (s2[i].wire == NULL)
+						continue;
+					if (!used_signals_nodrivers.check(s2[i])) {
+						if (!unused_bits.empty())
+							unused_bits += " ";
+						unused_bits += stringf("%d", i);
+					}
 				}
-			}
-			if (unused_bits.empty() || wire->port_id != 0)
+				if (unused_bits.empty() || wire->port_id != 0)
+					wire->attributes.erase("\\unused_bits");
+				else
+					wire->attributes["\\unused_bits"] = RTLIL::Const(unused_bits);
+			} else {
 				wire->attributes.erase("\\unused_bits");
-			else
-				wire->attributes["\\unused_bits"] = RTLIL::Const(unused_bits);
-		} else {
-			wire->attributes.erase("\\unused_bits");
+			}
 		}
 	}
 
+	int del_temp_wires_count = 0;
+	for (auto wire : del_wires_queue) {
+		if (ys_debug() || (check_public_name(wire->name) && verbose))
+			log_debug("  removing unused non-port wire %s.\n", wire->name.c_str());
+		else
+			del_temp_wires_count++;
+	}
 
-	pool<RTLIL::Wire*> del_wires;
+	module->remove(del_wires_queue);
+	count_rm_wires += GetSize(del_wires_queue);
 
-	int del_wires_count = 0;
-	for (auto wire : maybe_del_wires)
-		if (!used_signals.check_any(RTLIL::SigSpec(wire))) {
-			if (check_public_name(wire->name) && verbose) {
-				log_debug("  removing unused non-port wire %s.\n", wire->name.c_str());
-			}
-			del_wires.insert(wire);
-			del_wires_count++;
-		}
+	if (verbose && del_temp_wires_count)
+		log_debug("  removed %d unused temporary wires.\n", del_temp_wires_count);
 
-	module->remove(del_wires);
-	count_rm_wires += del_wires.size();
-
-	if (verbose && del_wires_count > 0)
-		log_debug("  removed %d unused temporary wires.\n", del_wires_count);
+	return !del_wires_queue.empty();
 }
 
 bool rmunused_module_init(RTLIL::Module *module, bool purge_mode, bool verbose)
@@ -447,10 +497,10 @@ void rmunused_module(RTLIL::Module *module, bool purge_mode, bool verbose, bool
 		module->design->scratchpad_set_bool("opt.did_something", true);
 
 	rmunused_module_cells(module, verbose);
-	rmunused_module_signals(module, purge_mode, verbose);
+	while (rmunused_module_signals(module, purge_mode, verbose)) { }
 
 	if (rminit && rmunused_module_init(module, purge_mode, verbose))
-		rmunused_module_signals(module, purge_mode, verbose);
+		while (rmunused_module_signals(module, purge_mode, verbose)) { }
 }
 
 struct OptCleanPass : public Pass {
@@ -496,6 +546,9 @@ struct OptCleanPass : public Pass {
 
 		ct_all.setup(design);
 
+		count_rm_cells = 0;
+		count_rm_wires = 0;
+
 		for (auto module : design->selected_whole_modules_warn()) {
 			if (module->has_processes_warn())
 				continue;
@@ -561,7 +614,7 @@ struct CleanPass : public Pass {
 		for (auto module : design->selected_whole_modules()) {
 			if (module->has_processes())
 				continue;
-			rmunused_module(module, purge_mode, false, false);
+			rmunused_module(module, purge_mode, ys_debug(), false);
 		}
 
 		log_suppressed();
diff --git a/passes/opt/opt_expr.cc b/passes/opt/opt_expr.cc
index b445afdc8..512ef0cbf 100644
--- a/passes/opt/opt_expr.cc
+++ b/passes/opt/opt_expr.cc
@@ -61,7 +61,7 @@ void replace_undriven(RTLIL::Design *design, RTLIL::Module *module)
 		}
 		if (wire->port_input)
 			driven_signals.add(sigmap(wire));
-		if (wire->port_output)
+		if (wire->port_output || wire->get_bool_attribute("\\keep"))
 			used_signals.add(sigmap(wire));
 		all_signals.add(sigmap(wire));
 	}
@@ -88,7 +88,7 @@ void replace_undriven(RTLIL::Design *design, RTLIL::Module *module)
 			}
 		}
 
-		log_debug("Setting undriven signal in %s to constant: %s = %s\n", RTLIL::id2cstr(module->name), log_signal(sig), log_signal(val));
+		log_debug("Setting undriven signal in %s to constant: %s = %s\n", log_id(module), log_signal(sig), log_signal(val));
 		module->connect(sig, val);
 		did_something = true;
 	}
@@ -104,10 +104,15 @@ void replace_undriven(RTLIL::Design *design, RTLIL::Module *module)
 				if (SigBit(initval[i]) == sig[i])
 					initval[i] = State::Sx;
 			}
-			if (initval.is_fully_undef())
+			if (initval.is_fully_undef()) {
+				log_debug("Removing init attribute from %s/%s.\n", log_id(module), log_id(wire));
 				wire->attributes.erase("\\init");
-			else
+				did_something = true;
+			} else if (initval != wire->attributes.at("\\init")) {
+				log_debug("Updating init attribute on %s/%s: %s\n", log_id(module), log_id(wire), log_signal(initval));
 				wire->attributes["\\init"] = initval;
+				did_something = true;
+			}
 		}
 	}
 }
diff --git a/passes/opt/opt_muxtree.cc b/passes/opt/opt_muxtree.cc
index dbebf21e0..6511e091b 100644
--- a/passes/opt/opt_muxtree.cc
+++ b/passes/opt/opt_muxtree.cc
@@ -184,6 +184,10 @@ struct OptMuxtreeWorker
 				log_debug("    Root of a mux tree: %s%s\n", log_id(mux2info[mux_idx].cell), root_enable_muxes.at(mux_idx) ? " (pure)" : "");
 				root_mux_rerun.erase(mux_idx);
 				eval_root_mux(mux_idx);
+				if (glob_abort_cnt == 0) {
+					log("  Giving up (too many iterations)\n");
+					return;
+				}
 			}
 
 		while (!root_mux_rerun.empty()) {
@@ -192,9 +196,14 @@ struct OptMuxtreeWorker
 			log_assert(root_enable_muxes.at(mux_idx));
 			root_mux_rerun.erase(mux_idx);
 			eval_root_mux(mux_idx);
+			if (glob_abort_cnt == 0) {
+				log("  Giving up (too many iterations)\n");
+				return;
+			}
 		}
 
 		log("  Analyzing evaluation results.\n");
+		log_assert(glob_abort_cnt > 0);
 
 		for (auto &mi : mux2info)
 		{
@@ -397,10 +406,8 @@ struct OptMuxtreeWorker
 
 	void eval_mux(knowledge_t &knowledge, int mux_idx, bool do_replace_known, bool do_enable_ports, int abort_count)
 	{
-		if (glob_abort_cnt == 0) {
-			log("  Giving up (too many iterations)\n");
+		if (glob_abort_cnt == 0)
 			return;
-		}
 		glob_abort_cnt--;
 
 		muxinfo_t &muxinfo = mux2info[mux_idx];
@@ -454,6 +461,7 @@ struct OptMuxtreeWorker
 
 	void eval_root_mux(int mux_idx)
 	{
+		log_assert(glob_abort_cnt > 0);
 		knowledge_t knowledge;
 		knowledge.known_inactive.resize(GetSize(bit2info));
 		knowledge.known_active.resize(GetSize(bit2info));
diff --git a/passes/pmgen/README.md b/passes/pmgen/README.md
index 7a46558b1..d0711c730 100644
--- a/passes/pmgen/README.md
+++ b/passes/pmgen/README.md
@@ -29,19 +29,25 @@ up in any future matches:
 
     pm.blacklist(some_cell);
 
-The `.run(callback_function)` method searches for all matches and calls the
-callback function for each found match:
+The `.run_<pattern_name>(callback_function)` method searches for all matches
+for the pattern`<pattern_name>` and calls the callback function for each found
+match:
 
-    pm.run([&](){
+    pm.run_foobar([&](){
         log("found matching 'foo' cell: %s\n", log_id(pm.st.foo));
         log("          with 'bar' cell: %s\n", log_id(pm.st.bar));
     });
 
 The `.pmg` file declares matcher state variables that are accessible via the
-`.st.<state_name>` members. (The `.st` member is of type `foobar_pm::state_t`.)
+`.st_<pattern_name>.<state_name>` members. (The `.st_<pattern_name>` member is
+of type `foobar_pm::state_<pattern_name>_t`.)
 
 Similarly the `.pmg` file declares user data variables that become members of
-`.ud`, a struct of type `foobar_pm::udata_t`.
+`.ud_<pattern_name>`, a struct of type `foobar_pm::udata_<pattern_name>_t`.
+
+There are four versions of the `run_<pattern_name>()` method: Without callback,
+callback without arguments, callback with reference to `pm`, and callback with
+reference to `pm.st_<pattern_name>`.
 
 
 The .pmg File Format
@@ -52,6 +58,12 @@ lines consist of whitespace-separated tokens.
 
 Lines in `.pmg` files starting with `//` are comments.
 
+Declaring a pattern
+-------------------
+
+A `.pmg` file contains one or more patterns. Each pattern starts with a line
+with the `pattern` keyword followed by the name of the pattern.
+
 Declaring state variables
 -------------------------
 
@@ -66,7 +78,7 @@ State variables are automatically managed by the generated backtracking algorith
 and saved and restored as needed.
 
 They are automatically initialized to the default constructed value of their type
-when `.run(callback_function)` is called.
+when `.run_<pattern_name>(callback_function)` is called.
 
 Declaring udata variables
 -------------------------
diff --git a/passes/pmgen/peepopt.cc b/passes/pmgen/peepopt.cc
index 78eb68c7a..e7f95cf85 100644
--- a/passes/pmgen/peepopt.cc
+++ b/passes/pmgen/peepopt.cc
@@ -40,7 +40,7 @@ struct PeepoptPass : public Pass {
 	}
 	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
 	{
-		log_header(design, "Executing PEEOPOPT pass (run peephole optimizers).\n");
+		log_header(design, "Executing PEEPOPT pass (run peephole optimizers).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/pmgen/peepopt_shiftmul.pmg b/passes/pmgen/peepopt_shiftmul.pmg
index 1f9b3c2b9..fe861b728 100644
--- a/passes/pmgen/peepopt_shiftmul.pmg
+++ b/passes/pmgen/peepopt_shiftmul.pmg
@@ -8,9 +8,13 @@ endmatch
 
 code shamt
 	shamt = port(shift, \B);
+	if (shamt.empty())
+		reject;
 	if (shamt[GetSize(shamt)-1] == State::S0) {
 		do {
 			shamt.remove(GetSize(shamt)-1);
+			if (shamt.empty())
+				reject;
 		} while (shamt[GetSize(shamt)-1] == State::S0);
 	} else
 	if (shift->type.in($shift, $shiftx) && param(shift, \B_SIGNED).as_bool()) {
diff --git a/passes/sat/expose.cc b/passes/sat/expose.cc
index 3add9a9eb..50ab38063 100644
--- a/passes/sat/expose.cc
+++ b/passes/sat/expose.cc
@@ -508,7 +508,7 @@ struct ExposePass : public Pass {
 				}
 
 				for (auto &conn : module->connections_)
-					conn.first = out_to_in_map(sigmap(conn.first));
+					conn.first = out_to_in_map(conn.first);
 			}
 
 			if (flag_cut)
diff --git a/passes/sat/fmcombine.cc b/passes/sat/fmcombine.cc
index cd75ca860..f64d99dc2 100644
--- a/passes/sat/fmcombine.cc
+++ b/passes/sat/fmcombine.cc
@@ -26,6 +26,8 @@ PRIVATE_NAMESPACE_BEGIN
 
 struct opts_t
 {
+	bool initeq = false;
+	bool anyeq = false;
 	bool fwd = false;
 	bool bwd = false;
 	bool nop = false;
@@ -56,7 +58,7 @@ struct FmcombineWorker
 		return newsig;
 	}
 
-	void import_prim_cell(Cell *cell, const string &suffix)
+	Cell *import_prim_cell(Cell *cell, const string &suffix)
 	{
 		Cell *c = module->addCell(cell->name.str() + suffix, cell->type);
 		c->parameters = cell->parameters;
@@ -64,6 +66,8 @@ struct FmcombineWorker
 
 		for (auto &conn : cell->connections())
 			c->setPort(conn.first, import_sig(conn.second, suffix));
+
+		return c;
 	}
 
 	void import_hier_cell(Cell *cell)
@@ -102,8 +106,24 @@ struct FmcombineWorker
 
 		for (auto cell : original->cells()) {
 			if (design->module(cell->type) == nullptr) {
-				import_prim_cell(cell, "_gold");
-				import_prim_cell(cell, "_gate");
+				if (opts.anyeq && cell->type.in("$anyseq", "$anyconst")) {
+					Cell *gold = import_prim_cell(cell, "_gold");
+					for (auto &conn : cell->connections())
+						module->connect(import_sig(conn.second, "_gate"), gold->getPort(conn.first));
+				} else {
+					Cell *gold = import_prim_cell(cell, "_gold");
+					Cell *gate = import_prim_cell(cell, "_gate");
+					if (opts.initeq) {
+						if (cell->type.in("$ff", "$dff", "$dffe",
+								"$dffsr", "$adff", "$dlatch", "$dlatchsr")) {
+							SigSpec gold_q = gold->getPort("\\Q");
+							SigSpec gate_q = gate->getPort("\\Q");
+							SigSpec en = module->Initstate(NEW_ID);
+							SigSpec eq = module->Eq(NEW_ID, gold_q, gate_q);
+							module->addAssume(NEW_ID, eq, en);
+						}
+					}
+				}
 			} else {
 				import_hier_cell(cell);
 			}
@@ -229,6 +249,13 @@ struct FmcombinePass : public Pass {
 		log("This is useful for formal test benches that check what differences in behavior\n");
 		log("a slight difference in input causes in a module.\n");
 		log("\n");
+		log("    -initeq\n");
+		log("        Insert assumptions that initially all FFs in both circuits have the\n");
+		log("        same initial values.\n");
+		log("\n");
+		log("    -anyeq\n");
+		log("        Do not duplicate $anyseq/$anyconst cells.\n");
+		log("\n");
 		log("    -fwd\n");
 		log("        Insert forward hint assumptions into the combined module.\n");
 		log("\n");
@@ -261,6 +288,14 @@ struct FmcombinePass : public Pass {
 			// 	filename = args[++argidx];
 			// 	continue;
 			// }
+			if (args[argidx] == "-initeq") {
+				opts.initeq = true;
+				continue;
+			}
+			if (args[argidx] == "-anyeq") {
+				opts.anyeq = true;
+				continue;
+			}
 			if (args[argidx] == "-fwd") {
 				opts.fwd = true;
 				continue;
diff --git a/passes/techmap/abc.cc b/passes/techmap/abc.cc
index 547115459..5b19d84fb 100644
--- a/passes/techmap/abc.cc
+++ b/passes/techmap/abc.cc
@@ -330,20 +330,33 @@ void extract_cell(RTLIL::Cell *cell, bool keepff)
 std::string remap_name(RTLIL::IdString abc_name, RTLIL::Wire **orig_wire = nullptr)
 {
 	std::string abc_sname = abc_name.substr(1);
-	if (abc_sname.substr(0, 5) == "ys__n") {
-		bool inv = abc_sname.back() == 'v';
-		if (inv) abc_sname.pop_back();
+	bool isnew = false;
+	if (abc_sname.substr(0, 4) == "new_")
+	{
+		abc_sname.erase(0, 4);
+		isnew = true;
+	}
+	if (abc_sname.substr(0, 5) == "ys__n")
+	{
 		abc_sname.erase(0, 5);
-		if (abc_sname.find_last_not_of("012345689") == std::string::npos) {
+		if (std::isdigit(abc_sname.at(0)))
+		{
 			int sid = std::stoi(abc_sname);
-			for (auto sig : signal_list) {
-				if (sig.id == sid && sig.bit.wire != nullptr) {
+			size_t postfix_start = abc_sname.find_first_not_of("0123456789");
+			std::string postfix = postfix_start != std::string::npos ? abc_sname.substr(postfix_start) : "";
+
+			if (sid < GetSize(signal_list))
+			{
+				auto sig = signal_list.at(sid);
+				if (sig.bit.wire != nullptr)
+				{
 					std::stringstream sstr;
 					sstr << "$abc$" << map_autoidx << "$" << sig.bit.wire->name.substr(1);
 					if (sig.bit.wire->width != 1)
 						sstr << "[" << sig.bit.offset << "]";
-					if (inv)
-						sstr << "_inv";
+					if (isnew)
+						sstr << "_new";
+					sstr << postfix;
 					if (orig_wire != nullptr)
 						*orig_wire = sig.bit.wire;
 					return sstr.str();
diff --git a/passes/techmap/dffinit.cc b/passes/techmap/dffinit.cc
index 48390488e..0ad33dc0e 100644
--- a/passes/techmap/dffinit.cc
+++ b/passes/techmap/dffinit.cc
@@ -102,7 +102,8 @@ struct DffinitPass : public Pass {
 				if (wire->attributes.count("\\init")) {
 					Const value = wire->attributes.at("\\init");
 					for (int i = 0; i < min(GetSize(value), GetSize(wire)); i++)
-						init_bits[sigmap(SigBit(wire, i))] = value[i];
+						if (value[i] != State::Sx)
+							init_bits[sigmap(SigBit(wire, i))] = value[i];
 				}
 				if (wire->port_output)
 					for (auto bit : sigmap(wire))
diff --git a/passes/techmap/flowmap.cc b/passes/techmap/flowmap.cc
index 0b7931e48..f5892a60e 100644
--- a/passes/techmap/flowmap.cc
+++ b/passes/techmap/flowmap.cc
@@ -397,7 +397,6 @@ struct FlowGraph
 		pool<RTLIL::SigBit> x, xi;
 
 		NodePrime source_prime = {source, true};
-		NodePrime sink_prime = {sink, false};
 		pool<NodePrime> visited;
 		vector<NodePrime> worklist = {source_prime};
 		while (!worklist.empty())
@@ -1382,7 +1381,8 @@ struct FlowmapWorker
 
 			vector<RTLIL::SigBit> input_nodes(lut_edges_bw[node].begin(), lut_edges_bw[node].end());
 			RTLIL::Const lut_table(State::Sx, max(1 << input_nodes.size(), 1 << minlut));
-			for (unsigned i = 0; i < (1 << input_nodes.size()); i++)
+			unsigned const mask = 1 << input_nodes.size();
+			for (unsigned i = 0; i < mask; i++)
 			{
 				ce.push();
 				for (size_t n = 0; n < input_nodes.size(); n++)
diff --git a/passes/techmap/libparse.cc b/passes/techmap/libparse.cc
index 991cc4498..349ccc115 100644
--- a/passes/techmap/libparse.cc
+++ b/passes/techmap/libparse.cc
@@ -94,7 +94,7 @@ int LibertyParser::lexer(std::string &str)
 
 	// search for identifiers, numbers, plus or minus.
 	if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_' || c == '-' || c == '+' || c == '.') {
-		str = c;
+		str = static_cast<char>(c);
 		while (1) {
 			c = f.get();
 			if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || ('0' <= c && c <= '9') || c == '_' || c == '-' || c == '+' || c == '.')
diff --git a/passes/techmap/zinit.cc b/passes/techmap/zinit.cc
index b46147fb9..2aefc091d 100644
--- a/passes/techmap/zinit.cc
+++ b/passes/techmap/zinit.cc
@@ -46,7 +46,7 @@ struct ZinitPass : public Pass {
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
 		{
-			if (args[argidx] == "-singleton") {
+			if (args[argidx] == "-all") {
 				all_mode = true;
 				continue;
 			}