diff --git a/Makefile b/Makefile
index 6639eb317..019db4559 100644
--- a/Makefile
+++ b/Makefile
@@ -744,6 +744,7 @@ OBJS += passes/cmds/splitfanout.o
 OBJS += passes/cmds/splitnets.o
 OBJS += passes/cmds/tee.o
 OBJS += passes/cmds/activity.o
+OBJS += passes/cmds/splitnetlist.o
 OBJS += passes/sat/sim.o
 
 include $(YOSYS_SRC)/passes/hierarchy/Makefile.inc
diff --git a/passes/cmds/splitnetlist.cc b/passes/cmds/splitnetlist.cc
new file mode 100644
index 000000000..2ea94c78e
--- /dev/null
+++ b/passes/cmds/splitnetlist.cc
@@ -0,0 +1,243 @@
+#include "kernel/sigtools.h"
+#include "kernel/yosys.h"
+#include <set>
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+// Recursively traverses backward from a sig, record if a cell was traversed, and push onto the cell's inputs.
+// Similarly with assign statements traverses lhs -> rhs
+void recordTransFanin(RTLIL::SigSpec &sig, dict<RTLIL::SigSpec, std::set<Cell *> *> &sig2CellsInFanin,
+		      dict<RTLIL::SigSpec, RTLIL::SigSpec> &lhsSig2RhsSig, std::set<Cell *> &visitedCells, std::set<RTLIL::SigSpec> &visitedSigSpec)
+{
+	if (sig.is_fully_const()) {
+		return;
+	}
+	if (visitedSigSpec.count(sig)) {
+		return;
+	}
+	visitedSigSpec.insert(sig);
+	if (sig2CellsInFanin.count(sig)) {
+		std::set<Cell *> *sigFanin = sig2CellsInFanin[sig];
+		for (std::set<Cell *>::iterator it = sigFanin->begin(); it != sigFanin->end(); it++) {
+			Cell *cell = *it;
+			if (visitedCells.count(cell)) {
+				continue;
+			}
+			visitedCells.insert(cell);
+			for (auto &conn : cell->connections()) {
+				IdString portName = conn.first;
+				RTLIL::SigSpec actual = conn.second;
+
+				if (cell->input(portName)) {
+					if (!actual.is_chunk()) {
+						for (auto it = actual.chunks().rbegin(); it != actual.chunks().rend(); ++it) {
+							RTLIL::SigSpec sub_actual = *it;
+							recordTransFanin(sub_actual, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
+						}
+					} else {
+						recordTransFanin(actual, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
+					}
+				}
+			}
+		}
+	}
+	if (lhsSig2RhsSig.count(sig)) {
+		RTLIL::SigSpec rhs = lhsSig2RhsSig[sig];
+		recordTransFanin(rhs, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
+	}
+}
+
+// Signal cell driver(s), precompute a cell output signal to a cell map
+void sigCellDrivers(RTLIL::Design *design, dict<RTLIL::SigSpec, std::set<Cell *> *> &sig2CellsInFanin)
+{
+	for (auto cell : design->top_module()->cells()) {
+		for (auto &conn : cell->connections()) {
+			IdString portName = conn.first;
+			RTLIL::SigSpec actual = conn.second;
+			std::set<Cell *> *newSet;
+			if (cell->output(portName)) {
+				if (!actual.is_chunk()) {
+					for (auto it = actual.chunks().rbegin(); it != actual.chunks().rend(); ++it) {
+						RTLIL::SigSpec sub_actual = *it;
+						if (sig2CellsInFanin.count(sub_actual)) {
+							newSet = sig2CellsInFanin[sub_actual];
+						} else {
+							newSet = new std::set<Cell *>;
+							sig2CellsInFanin[sub_actual] = newSet;
+						}
+						newSet->insert(cell);
+					}
+				} else {
+					if (sig2CellsInFanin.count(actual)) {
+						newSet = sig2CellsInFanin[actual];
+					} else {
+						newSet = new std::set<Cell *>;
+						sig2CellsInFanin[actual] = newSet;
+					}
+					newSet->insert(cell);
+				}
+			}
+		}
+	}
+}
+
+// Assign statements fanin, traces the lhs to rhs sigspecs and precompute a map
+void lhs2rhs(RTLIL::Design *design, dict<RTLIL::SigSpec, RTLIL::SigSpec> &lhsSig2rhsSig)
+{
+	for (auto it = design->top_module()->connections().begin(); it != design->top_module()->connections().end(); ++it) {
+		RTLIL::SigSpec lhs = it->first;
+		RTLIL::SigSpec rhs = it->second;
+		if (rhs.is_fully_const()) {
+			continue;
+		}
+		if (!lhs.is_chunk()) {
+			if (lhs.chunks().size() != rhs.chunks().size()) {
+				auto rit = rhs.chunks().rbegin();
+				long unsigned rhsSize = 0;
+				while (rit != rhs.chunks().rend()) {
+					RTLIL::SigSpec sub_rhs = *rit;
+					if (sub_rhs.is_fully_const()) {
+						rhsSize += (sub_rhs.as_chunk()).width;
+					} else {
+						rhsSize++;
+					}
+					rit++;
+				}
+				if (lhs.chunks().size() != rhsSize) {
+					continue;
+				}
+			}
+			auto lit = lhs.chunks().rbegin();
+			auto rit = rhs.chunks().rbegin();
+			while (rit != rhs.chunks().rend()) {
+				RTLIL::SigSpec sub_lhs = *lit;
+				RTLIL::SigSpec sub_rhs = *rit;
+				if (sub_rhs.is_fully_const()) {
+					int constSize = (sub_rhs.as_chunk()).width;
+					while (constSize--) {
+						lit++;
+					}
+					rit++;
+					continue;
+				}
+				lhsSig2rhsSig[sub_lhs] = sub_rhs;
+				lit++;
+				rit++;
+			}
+		} else {
+			lhsSig2rhsSig[lhs] = rhs;
+		}
+	}
+}
+
+std::string_view rtrim_until(std::string_view str, char c)
+{
+	auto pos = str.rfind(c);
+	if (pos != std::string_view::npos)
+		str = str.substr(0, pos);
+	return str;
+}
+
+std::string id2String(RTLIL::IdString internal_id)
+{
+	const char *str = internal_id.c_str();
+	std::string result = str;
+	return result;
+}
+
+std::string replaceAll(std::string_view str, std::string_view from, std::string_view to)
+{
+	size_t start_pos = 0;
+	std::string result(str);
+	while ((start_pos = result.find(from, start_pos)) != std::string::npos) {
+		result.replace(start_pos, from.length(), to);
+		start_pos += to.length(); // Handles case where 'to' is a substr of 'from'
+	}
+	return result;
+}
+
+struct SplitNetlist : public ScriptPass {
+	SplitNetlist()
+	    : ScriptPass("splitnetlist", "Splits a netlist into multiple modules using transitive fanin grouping. \
+	       The output names that belong in the same logical cluster have to have the same prefix: <prefix>_<name>")
+	{
+	}
+	void script() {}
+
+	void execute(std::vector<std::string>, RTLIL::Design *design) override
+	{
+		if (design == nullptr) {
+			log_error("No design object");
+			return;
+		}
+		// Precompute cell output sigspec to cell map
+		dict<RTLIL::SigSpec, std::set<Cell *> *> sig2CellsInFanin;
+		sigCellDrivers(design, sig2CellsInFanin);
+		// Precompute lhs to rhs sigspec map
+		dict<RTLIL::SigSpec, RTLIL::SigSpec> lhsSig2RhsSig;
+		lhs2rhs(design, lhsSig2RhsSig);
+		// Struct representing a cluster
+		typedef struct CellsAndSigs {
+			std::set<Cell *> visitedCells;
+			std::set<RTLIL::SigSpec> visitedSigSpec;
+		} CellsAndSigs;
+		// Cluster mapped by prefix
+		typedef std::map<std::string, CellsAndSigs> CellName_ObjectMap;
+		CellName_ObjectMap cellName_ObjectMap;
+		// Record logic cone by output sharing the same prefix
+		for (auto wire : design->top_module()->wires()) {
+			if (!wire->port_output)
+				continue;
+			std::string output_port_name = wire->name.c_str();
+			std::string_view po_prefix = rtrim_until(std::string_view(output_port_name), '_');
+			std::set<Cell *> visitedCells;
+			std::set<RTLIL::SigSpec> visitedSigSpec;
+			RTLIL::SigSpec actual = wire;
+			// Visit the output sigspec
+			recordTransFanin(actual, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
+			// Visit the output sigspec bits
+			for (int i = 0; i < actual.size(); i++) {
+				SigSpec bit_sig = actual.extract(i, 1);
+				recordTransFanin(bit_sig, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
+			}
+			// Record the visited objects in the corresponding cluster
+			CellName_ObjectMap::iterator itr = cellName_ObjectMap.find(std::string(po_prefix));
+			if (itr == cellName_ObjectMap.end()) {
+				CellsAndSigs components;
+				for (auto cell : visitedCells) {
+					components.visitedCells.insert(cell);
+				}
+				for (auto sig : visitedSigSpec) {
+					components.visitedSigSpec.insert(sig);
+				}
+				cellName_ObjectMap.emplace(std::string(po_prefix), components);
+			} else {
+				CellsAndSigs &components = itr->second;
+				for (auto cell : visitedCells) {
+					components.visitedCells.insert(cell);
+				}
+				for (auto sig : visitedSigSpec) {
+					components.visitedSigSpec.insert(sig);
+				}
+			}
+		}
+		// Create submod attributes for the submod command
+		for (CellName_ObjectMap::iterator itr = cellName_ObjectMap.begin(); itr != cellName_ObjectMap.end(); itr++) {
+			// std::cout << "Cluster name: " << itr->first << std::endl;
+			CellsAndSigs &components = itr->second;
+			for (auto cell : components.visitedCells) {
+				cell->set_string_attribute(RTLIL::escape_id("submod"), itr->first);
+				// std::cout << "  CELL: " << cell->name.c_str() << std::endl;
+			}
+			// for (auto sigspec : components.visitedSigSpec) {
+			//  std::cout << "  SIG: " << SigName(sigspec) << std::endl;
+			// }
+			// std::cout << std::endl;
+		}
+		// Execute the submod command
+		Pass::call(design, "submod -copy");
+	}
+} SplitNetlist;
+
+PRIVATE_NAMESPACE_END
diff --git a/passes/sat/sim.cc b/passes/sat/sim.cc
index 395c5abb5..c4bfe3ea1 100644
--- a/passes/sat/sim.cc
+++ b/passes/sat/sim.cc
@@ -2355,8 +2355,7 @@ struct VCDWriter : public OutputWriter
 		}
 
 		if (!worker->timescale.empty())
-			vcdfile << stringf("$timescale %s $end\n", worker->timescale.c_str());
-
+			vcdfile << stringf("$timescale 1%s $end\n", worker->timescale.c_str());
 		worker->top->write_output_header(
 			[this](IdString name) { vcdfile << stringf("$scope module %s $end\n", log_id(name)); },
 			[this]() { vcdfile << stringf("$upscope $end\n");},
@@ -2500,6 +2499,8 @@ struct AnnotateActivity : public OutputWriter {
 		SignalActivityDataMap::iterator itr = dataMap.find(clk);
 		std::vector<uint32_t> &clktoggleCounts = itr->second.toggleCounts;
 		double clk_period = real_timescale * (double)max_time / (clktoggleCounts[0] / 2);
+		double frequency = 1 / clk_period;
+		worker->top->module->set_string_attribute("$FREQUENCY", std::to_string(frequency));
 		if (debug) {
 			std::cout << "Clock toggle count: " << clktoggleCounts[0] << "\n";
 			std::cout << "Max time: " << max_time << "\n";