icetime progress

5 files changed, 312 insertions, 121 deletions

diff --git a/icetime/.gitignore b/icetime/.gitignore
index 8fee1fd..fd24fa8 100644
--- a/icetime/.gitignore
+++ b/icetime/.gitignore
@@ -1,4 +1,5 @@
 icetime
+timings.inc
 test[0-9]*
 *.d
 *.o
diff --git a/icetime/Makefile b/icetime/Makefile
index 7edfc6c..31f1ac5 100644
--- a/icetime/Makefile
+++ b/icetime/Makefile
@@ -6,6 +6,12 @@ all: icetime
 
 icetime: icetime.o
 
+icetime.o: icetime.cc timings.inc
+
+timings.inc: timings.py
+	python3 timings.py > timings.inc.new
+	mv timings.inc.new timings.inc
+
 install: all
 	mkdir -p $(DESTDIR)$(PREFIX)/bin
 	cp icetime $(DESTDIR)$(PREFIX)/bin/icetime
@@ -24,7 +30,7 @@ test0 test1 test2 test3 test4 test5 test6 test7 test8 test9: icetime
 	yosys $@.ys
 
 run0 run1 run2 run3 run4 run5 run6 run7 run8 run9: icetime
-	./icetime -P tq144 -p $(subst run,test,$@).pcf $(subst run,test,$@).asc $(subst run,test,$@)_out.v
+	./icetime -t -P tq144 -p $(subst run,test,$@).pcf $(subst run,test,$@).asc $(subst run,test,$@)_out.v
 
 show0 show1 show2 show3 show4 show5 show6 show7 show8 show9: icetime
 	bash show.sh $(subst show,test,$@)
@@ -35,7 +41,7 @@ test: test0 test1 test2 test3 test4 test5 test6 test7 test8 test9
 show: show0 show1 show2 show3 show4 show5 show6 show7 show8 show9
 
 clean:
-	rm -f icetime *.o *.d
+	rm -f icetime timings.inc *.o *.d
 	rm -rf test[0-9]*
 
 -include *.d
diff --git a/icetime/icetime.cc b/icetime/icetime.cc
index 09a4ca4..ad11831 100644
--- a/icetime/icetime.cc
+++ b/icetime/icetime.cc
@@ -31,6 +31,7 @@
 #define MAX_SPAN_HACK 1
 
 FILE *fin, *fout;
+bool verbose = false;
 
 std::string config_device, selected_package;
 std::vector<std::vector<std::string>> config_tile_type;
@@ -460,28 +461,43 @@ void read_chipdb()
 				std::pair<int, int>(x, y);
 	}
 
-
-#if 1
-	for (int net : used_nets)
+	if (verbose)
 	{
-		printf("// NET %d:\n", net);
-		for (auto seg : net_to_segments[net])
-			printf("//  SEG %d %d %s\n", seg.x, seg.y, seg.name.c_str());
-		for (auto other : net_buffers[net])
-			printf("//  BUFFER %d %d %d\n", connection_pos[std::pair<int, int>(net, other)].first,
-					connection_pos[std::pair<int, int>(net, other)].second, other);
-		for (auto other : net_rbuffers[net])
-			printf("//  RBUFFER %d %d %d\n", connection_pos[std::pair<int, int>(net, other)].first,
-					connection_pos[std::pair<int, int>(net, other)].second, other);
-		for (auto other : net_routing[net])
-			printf("//  ROUTE %d %d %d\n", connection_pos[std::pair<int, int>(net, other)].first,
-					connection_pos[std::pair<int, int>(net, other)].second, other);
+		for (int net : used_nets)
+		{
+			printf("// NET %d:\n", net);
+			for (auto seg : net_to_segments[net])
+				printf("//  SEG %d %d %s\n", seg.x, seg.y, seg.name.c_str());
+			for (auto other : net_buffers[net])
+				printf("//  BUFFER %d %d %d\n", connection_pos[std::pair<int, int>(net, other)].first,
+						connection_pos[std::pair<int, int>(net, other)].second, other);
+			for (auto other : net_rbuffers[net])
+				printf("//  RBUFFER %d %d %d\n", connection_pos[std::pair<int, int>(net, other)].first,
+						connection_pos[std::pair<int, int>(net, other)].second, other);
+			for (auto other : net_routing[net])
+				printf("//  ROUTE %d %d %d\n", connection_pos[std::pair<int, int>(net, other)].first,
+						connection_pos[std::pair<int, int>(net, other)].second, other);
+		}
 	}
-#endif
 }
 
 bool is_primary(std::string cell_name, std::string out_port)
 {
+	auto cell_type = netlist_cell_types[cell_name];
+
+	if (cell_type == "SB_RAM40_4K")
+		return true;
+
+	if (cell_type == "LogicCell40" && out_port == "lcout")
+	{
+		// SEQ_MODE = "4'bX...";
+		bool dff_enable = netlist_cell_params[cell_name]["SEQ_MODE"][3] == '1';
+		return dff_enable;
+	}
+
+	if (cell_type == "PRE_IO")
+		return true;
+
 	return false;
 }
 
@@ -556,7 +572,7 @@ const std::set<std::string> &get_inports(std::string cell_type)
 		inports_map["ICE_CARRY_IN_MUX"] = { "carryinitin" };
 
 		inports_map["LogicCell40"] = { "clk", "carryin", "in0", "in1", "in2", "in3", "sr", "ce" };
-		inports_map["PRE_IO"] = { "INPUTCLK", "OUTPUTCLK", "LATCHINPUTVALUE", "CLOCKENABLE", "OUTPUTENABLE", "DOUT1", "DOUT0" };
+		inports_map["PRE_IO"] = { "INPUTCLK", "OUTPUTCLK", "LATCHINPUTVALUE", "CLOCKENABLE", "OUTPUTENABLE", "DOUT1", "DOUT0", "PADIN" };
 
 		inports_map["SB_RAM40_4K"] = { "RCLK", "RCLKE", "RE", "WCLK", "WCLKE", "WE" };
 
@@ -569,6 +585,8 @@ const std::set<std::string> &get_inports(std::string cell_type)
 			inports_map["SB_RAM40_4K"].insert(stringf("RADDR[%d]", i));
 			inports_map["SB_RAM40_4K"].insert(stringf("WADDR[%d]", i));
 		}
+
+		inports_map["INTERCONN"] = { "I" };
 	}
 
 	if (inports_map.count(cell_type) == 0) {
@@ -579,9 +597,21 @@ const std::set<std::string> &get_inports(std::string cell_type)
 	return inports_map.at(cell_type);
 }
 
+#include "timings.inc"
+
 double get_delay(std::string cell_type, std::string in_port, std::string out_port)
 {
-	return 1.0;
+	if (cell_type == "INTERCONN")
+		return 0;
+
+	if (config_device == "1k")
+		return get_delay_1k(cell_type, in_port, out_port);
+
+	if (config_device == "8k")
+		return get_delay_8k(cell_type, in_port, out_port);
+
+	fprintf(stderr, "No built-in timing database for '%s' devices!\n", config_device.c_str());
+	exit(1);
 }
 
 struct TimingAnalysis
@@ -589,6 +619,9 @@ struct TimingAnalysis
 	// net_driver[<net_name>] = { <cell_name>, <cell_port> }
 	std::map<std::string, std::pair<std::string, std::string>> net_driver;
 
+	// net_max_setup[<net_name>] = { <setup_time>, <cell_name>, <cell_port> }
+	std::map<std::string, std::tuple<double, std::string, std::string>> net_max_setup;
+
 	// net_max_path_parent[<net_name>] = { <parent_net>, <cell_name>, <inport>, <outport>, <delay> }
 	std::map<std::string, std::tuple<std::string, std::string, std::string, std::string, double>> net_max_path_parent;
 
@@ -609,20 +642,28 @@ struct TimingAnalysis
 
 		auto &driver_cell = net_driver.at(net).first;
 		auto &driver_port = net_driver.at(net).second;
+		auto &driver_type = netlist_cell_types.at(driver_cell);
 
 		if (is_primary(driver_cell, driver_port)) {
-			net_max_path_delay[net] = 0;
+			net_max_path_delay[net] = get_delay(driver_type, "*clkedge*", driver_port);
 			return 0;
 		}
 
-		auto &driver_type = netlist_cell_types.at(driver_cell);
-		auto &driver_inputs = get_inports(driver_type);
-
-		for (auto &inport : driver_inputs)
+		for (auto &inport : get_inports(driver_type))
 		{
-			if (inport == "clk" || inport == "INPUTCLK" || inport == "OUTPUTCLK")
+			if (inport == "clk" || inport == "INPUTCLK" || inport == "OUTPUTCLK" || inport == "PADIN")
 				continue;
 
+			if (driver_type == "LogicCell40" && driver_port == "carryout") {
+				if (inport == "in0" || inport == "in3")
+					continue;
+			}
+
+			if (driver_type == "LogicCell40" && (driver_port == "ltout" || driver_port == "lcout")) {
+				if (inport == "carryin")
+					continue;
+			}
+
 			std::string *in_net = &netlist_cell_ports.at(driver_cell).at(inport);
 			while (net_assignments.count(*in_net))
 				in_net = &net_assignments.at(*in_net);
@@ -657,8 +698,20 @@ struct TimingAnalysis
 			if (net_name == "")
 				continue;
 
-			if (get_inports(netlist_cell_types.at(cell_name)).count(port_name))
+			auto &cell_type = netlist_cell_types.at(cell_name);
+
+			if (get_inports(cell_type).count(port_name)) {
+				std::string n = net_name;
+				while (1) {
+					double setup_time = get_delay(cell_type, port_name, "*setup*");
+					if (setup_time >= std::get<0>(net_max_setup[n]))
+						net_max_setup[n] = std::make_tuple(setup_time, cell_name, port_name);
+					if (net_assignments.count(n) == 0)
+						break;
+					n = net_assignments.at(n);
+				}
 				continue;
+			}
 
 			net_driver[net_name] = { cell_name, port_name };
 			all_nets.insert(net_name);
@@ -667,7 +720,7 @@ struct TimingAnalysis
 		global_max_path_delay = 0;
 
 		for (auto &net : all_nets) {
-			double d = calc_net_max_path_delay(net);
+			double d = calc_net_max_path_delay(net) + std::get<0>(net_max_setup[net]);
 			if (d > global_max_path_delay) {
 				global_max_path_delay = d;
 				global_max_path_net = net;
@@ -675,18 +728,47 @@ struct TimingAnalysis
 		}
 	}
 
-	void report()
+	void report(std::string n = std::string())
 	{
 		std::vector<std::string> lines;
 		std::set<std::string> visited_nets;
 
-		std::string n = global_max_path_net;
+		if (n.empty()) {
+			n = global_max_path_net;
+			printf("Report for longest path:\n\n");
+		} else {
+			printf("Requested report for net %s:\n\n", n.c_str());
+		}
+
+		if (net_max_path_delay.count(n) == 0) {
+			printf("Net not found: %s\n", n.c_str());
+			return;
+		}
+
+		double delay = net_max_path_delay.at(n);
+
+		int logic_levels = 0;
 		bool last_line = true;
 
+		auto &user = net_max_setup[n];
+
+		if (!std::get<1>(user).empty()) {
+			lines.push_back(stringf("        %s (%s) %s [setup]: %.3f ns", std::get<1>(user).c_str(),
+					netlist_cell_types.at(std::get<1>(user)).c_str(), std::get<2>(user).c_str(), std::get<0>(user)));
+			delay += std::get<0>(user);
+		}
+
 		while (1)
 		{
-			if (net_max_path_parent.count(n) == 0) {
+			if (net_max_path_parent.count(n) == 0)
+			{
 				lines.push_back(stringf("%10.3f ns %s", calc_net_max_path_delay(n), n.c_str()));
+
+				auto &driver_cell = net_driver.at(n).first;
+				auto &driver_port = net_driver.at(n).second;
+				auto &driver_type = netlist_cell_types.at(driver_cell);
+				lines.push_back(stringf("        %s (%s) [clkedge] -> %s: %.3f ns", driver_cell.c_str(),
+						driver_type.c_str(), driver_port.c_str(), calc_net_max_path_delay(n)));
 				break;
 			}
 
@@ -697,8 +779,10 @@ struct TimingAnalysis
 
 			auto &entry = net_max_path_parent.at(n);
 
-			if (last_line || netlist_cell_types.at(std::get<1>(entry)) == "LogicCell40")
+			if (last_line || netlist_cell_types.at(std::get<1>(entry)) == "LogicCell40") {
 				lines.push_back(stringf("%10.3f ns %s", calc_net_max_path_delay(n), n.c_str()));
+				logic_levels++;
+			}
 
 			lines.push_back(stringf("        %s (%s) %s -> %s: %.3f ns", std::get<1>(entry).c_str(),
 					netlist_cell_types.at(std::get<1>(entry)).c_str(), std::get<2>(entry).c_str(),
@@ -711,6 +795,11 @@ struct TimingAnalysis
 
 		for (int i = int(lines.size())-1; i >= 0; i--)
 			printf("%s\n", lines[i].c_str());
+
+		printf("\n");
+		printf("Total number of logic levels: %d\n", logic_levels);
+		printf("Total path delay: %.2f ns (%.2f MHz)\n", delay, 1000.0 / delay);
+		printf("\n");
 	}
 };
 
@@ -1517,27 +1606,28 @@ void make_interconn(const net_segment_t &src, FILE *graph_f)
 	worker.build_net_tree(src.net);
 	worker.build_seg_tree(src);
 
-#if 1
-	printf("// INTERCONN %d %d %s %d\n", src.x, src.y, src.name.c_str(), src.net);
-	std::function<void(int,int)> print_net_tree = [&] (int net, int indent) {
-		printf("// %*sNET_TREE %d\n", indent, "", net);
-		for (int child : worker.net_tree.at(net))
-			print_net_tree(child, indent+2);
-	};
-	std::function<void(const net_segment_t&,int,bool)> print_seg_tree = [&] (const net_segment_t &seg, int indent, bool chain) {
-		printf("// %*sSEG_TREE %d %d %s %d\n", indent, chain ? "`" : "", seg.x, seg.y, seg.name.c_str(), seg.net);
-		if (worker.seg_tree.count(seg)) {
-			auto &children = worker.seg_tree.at(seg);
-			bool child_chain = children.size() == 1;
-			for (auto &child : children)
-				print_seg_tree(child, child_chain ? (chain ? indent : indent+1) : indent+2, child_chain);
-		} else {
-			printf("// %*s  DEAD_END (!)\n", indent, "");
-		}
-	};
-	print_net_tree(src.net, 2);
-	print_seg_tree(src, 2, false);
-#endif
+	if (verbose)
+	{
+		printf("// INTERCONN %d %d %s %d\n", src.x, src.y, src.name.c_str(), src.net);
+		std::function<void(int,int)> print_net_tree = [&] (int net, int indent) {
+			printf("// %*sNET_TREE %d\n", indent, "", net);
+			for (int child : worker.net_tree.at(net))
+				print_net_tree(child, indent+2);
+		};
+		std::function<void(const net_segment_t&,int,bool)> print_seg_tree = [&] (const net_segment_t &seg, int indent, bool chain) {
+			printf("// %*sSEG_TREE %d %d %s %d\n", indent, chain ? "`" : "", seg.x, seg.y, seg.name.c_str(), seg.net);
+			if (worker.seg_tree.count(seg)) {
+				auto &children = worker.seg_tree.at(seg);
+				bool child_chain = children.size() == 1;
+				for (auto &child : children)
+					print_seg_tree(child, child_chain ? (chain ? indent : indent+1) : indent+2, child_chain);
+			} else {
+				printf("// %*s  DEAD_END (!)\n", indent, "");
+			}
+		};
+		print_net_tree(src.net, 2);
+		print_seg_tree(src, 2, false);
+	}
 
 	for (auto &seg : worker.target_segs) {
 		net_assignments[net_name(seg.net)] = seg_name(seg);
@@ -1564,13 +1654,26 @@ void help(const char *cmd)
 	printf("        write a graphviz description of the interconnect tree\n");
 	printf("        that includes the given net to 'icetime_graph.dot'.\n");
 	printf("\n");
+	printf("    -t\n");
+	printf("        print a timing estimate (based on topological timing\n");
+	printf("        analysis)\n");
+	printf("\n");
+	printf("    -T <net_name>\n");
+	printf("        print a timing estimate for the specified net\n");
+	printf("\n");
+	printf("    -v\n");
+	printf("        verbose mode (print all interconnect trees)\n");
+	printf("\n");
 	exit(1);
 }
 
 int main(int argc, char **argv)
 {
+	bool print_timing = false;
+	std::vector<std::string> print_timing_nets;
+
 	int opt;
-	while ((opt = getopt(argc, argv, "p:P:g:")) != -1)
+	while ((opt = getopt(argc, argv, "p:P:g:tT:v")) != -1)
 	{
 		switch (opt)
 		{
@@ -1584,6 +1687,15 @@ int main(int argc, char **argv)
 		case 'g':
 			graph_nets.insert(atoi(optarg));
 			break;
+		case 't':
+			print_timing = true;
+			break;
+		case 'T':
+			print_timing_nets.push_back(optarg);
+			break;
+		case 'v':
+			verbose = true;
+			break;
 		default:
 			help(argv[0]);
 		}
@@ -1595,7 +1707,7 @@ int main(int argc, char **argv)
 			perror("Can't open input file");
 			exit(1);
 		}
-		fout = stdout;
+		fout = nullptr;
 	} else
 	if (optind+2 == argc) {
 		fin = fopen(argv[optind], "r");
@@ -1603,10 +1715,14 @@ int main(int argc, char **argv)
 			perror("Can't open input file");
 			exit(1);
 		}
-		fout = fopen(argv[optind+1], "w");
-		if (fout == nullptr) {
-			perror("Can't open output file");
-			exit(1);
+		if (std::string(argv[optind+1]) == "-") {
+			fout = stdout;
+		} else {
+			fout = fopen(argv[optind+1], "w");
+			if (fout == nullptr) {
+				perror("Can't open output file");
+				exit(1);
+			}
 		}
 	} else
 		help(argv[0]);
@@ -1731,84 +1847,102 @@ int main(int argc, char **argv)
 			extra_wires.insert(port.second);
 		}
 
-	fprintf(fout, "module chip (");
-	const char *io_sep = "";
-	for (auto io : io_names) {
-		fprintf(fout, "%s%s", io_sep, io.c_str());
-		io_sep = ", ";
-	}
-	fprintf(fout, ");\n");
+	if (fout != NULL)
+	{
+		fprintf(fout, "module chip (");
+		const char *io_sep = "";
+		for (auto io : io_names) {
+			fprintf(fout, "%s%s", io_sep, io.c_str());
+			io_sep = ", ";
+		}
+		fprintf(fout, ");\n");
 
-	for (int net : declared_nets)
-		fprintf(fout, "  wire net_%d;\n", net);
+		for (int net : declared_nets)
+			fprintf(fout, "  wire net_%d;\n", net);
 
-	for (auto net : extra_wires)
-		fprintf(fout, "  wire %s;\n", net.c_str());
-	
-	for (auto &it : net_assignments)
-		fprintf(fout, "  assign %s = %s;\n", it.first.c_str(), it.second.c_str());
+		for (auto net : extra_wires)
+			fprintf(fout, "  wire %s;\n", net.c_str());
 
-	fprintf(fout, "  wire gnd, vcc;\n");
-	fprintf(fout, "  GND gnd_cell (.Y(gnd));\n");
-	fprintf(fout, "  VCC vcc_cell (.Y(vcc));\n");
+		for (auto &it : net_assignments)
+			fprintf(fout, "  assign %s = %s;\n", it.first.c_str(), it.second.c_str());
 
-	for (auto &str : extra_vlog)
-		fprintf(fout, "%s", str.c_str());
+		fprintf(fout, "  wire gnd, vcc;\n");
+		fprintf(fout, "  GND gnd_cell (.Y(gnd));\n");
+		fprintf(fout, "  VCC vcc_cell (.Y(vcc));\n");
 
-	for (auto it : netlist_cell_types)
-	{
-		const char *sep = "";
-		fprintf(fout, "  %s ", it.second.c_str());
-		if (netlist_cell_params.count(it.first)) {
-			fprintf(fout, "#(");
-			for (auto port : netlist_cell_params[it.first]) {
-				fprintf(fout, "%s\n    .%s(%s)", sep, port.first.c_str(), port.second.c_str());
-				sep = ",";
+		for (auto &str : extra_vlog)
+			fprintf(fout, "%s", str.c_str());
+
+		for (auto it : netlist_cell_types)
+		{
+			const char *sep = "";
+			fprintf(fout, "  %s ", it.second.c_str());
+			if (netlist_cell_params.count(it.first)) {
+				fprintf(fout, "#(");
+				for (auto port : netlist_cell_params[it.first]) {
+					fprintf(fout, "%s\n    .%s(%s)", sep, port.first.c_str(), port.second.c_str());
+					sep = ",";
+				}
+				fprintf(fout, "\n  ) ");
+				sep = "";
 			}
-			fprintf(fout, "\n  ) ");
-			sep = "";
-		}
 
-		fprintf(fout, "%s (", it.first.c_str());
-		std::map<std::string, std::vector<std::string>> multibit_ports;
+			fprintf(fout, "%s (", it.first.c_str());
+			std::map<std::string, std::vector<std::string>> multibit_ports;
 
-		for (auto port : netlist_cell_ports[it.first])
-		{
-			size_t open_bracket_pos = port.first.find('[');
-			if (open_bracket_pos != std::string::npos) {
-				std::string base_name = port.first.substr(0, open_bracket_pos);
-				int bit_index = atoi(port.first.substr(open_bracket_pos+1).c_str());
-				if (multibit_ports[base_name].size() <= bit_index)
-					multibit_ports[base_name].resize(bit_index+1);
-				multibit_ports[base_name][bit_index] = port.second;
-				continue;
+			for (auto port : netlist_cell_ports[it.first])
+			{
+				size_t open_bracket_pos = port.first.find('[');
+				if (open_bracket_pos != std::string::npos) {
+					std::string base_name = port.first.substr(0, open_bracket_pos);
+					int bit_index = atoi(port.first.substr(open_bracket_pos+1).c_str());
+					if (multibit_ports[base_name].size() <= bit_index)
+						multibit_ports[base_name].resize(bit_index+1);
+					multibit_ports[base_name][bit_index] = port.second;
+					continue;
+				}
+
+				fprintf(fout, "%s\n    .%s(%s)", sep, port.first.c_str(), port.second.c_str());
+				sep = ",";
 			}
 
-			fprintf(fout, "%s\n    .%s(%s)", sep, port.first.c_str(), port.second.c_str());
-			sep = ",";
-		}
+			for (auto it : multibit_ports)
+			{
+				fprintf(fout, "%s\n    .%s({", sep, it.first.c_str());
+				sep = ",";
 
-		for (auto it : multibit_ports)
-		{
-			fprintf(fout, "%s\n    .%s({", sep, it.first.c_str());
-			sep = ",";
-
-			const char *sepsep = "";
-			for (int i = int(it.second.size())-1; i >= 0; i--) {
-				std::string wire_name = it.second[i];
-				fprintf(fout, "%s%s", sepsep, wire_name.c_str());
-				sepsep = ", ";
+				const char *sepsep = "";
+				for (int i = int(it.second.size())-1; i >= 0; i--) {
+					std::string wire_name = it.second[i];
+					fprintf(fout, "%s%s", sepsep, wire_name.c_str());
+					sepsep = ", ";
+				}
+				fprintf(fout, "})");
 			}
-			fprintf(fout, "})");
+
+			fprintf(fout, "\n  );\n");
 		}
 
-		fprintf(fout, "\n  );\n");
+		fprintf(fout, "endmodule\n");
 	}
 
-	fprintf(fout, "endmodule\n");
-
-	TimingAnalysis ta;
-	ta.report();
+	if (print_timing || !print_timing_nets.empty())
+	{
+		printf("\n");
+		printf("icetime topological timing analysis report\n");
+		printf("==========================================\n");
+		printf("\n");
+
+		TimingAnalysis ta;
+		for (auto &n : print_timing_nets)
+			ta.report(n);
+		ta.report();
+	}
+	else
+	{
+		TimingAnalysis ta;
+		printf("// Timing estimate: %.2f ns (%.2f MHz)\n", ta.global_max_path_delay, 1000.0 / ta.global_max_path_delay);
+	}
 
 	return 0;
 }
diff --git a/icetime/mktest.py b/icetime/mktest.py
index b56a12f..ec33ec3 100644
--- a/icetime/mktest.py
+++ b/icetime/mktest.py
@@ -148,6 +148,7 @@ with open("%s.ys" % sys.argv[1], "w") as f:
     print("equiv_status -assert", file=f)
 
 assert os.system("bash ../icefuzz/icecube.sh %s.v" % sys.argv[1]) == 0
+os.rename("%s.tmp/outputs/netlist/top_timing.rpt" % sys.argv[1], "%s.rpt" % sys.argv[1])
 os.rename("%s.v" % sys.argv[1], "%s_in.v" % sys.argv[1])
 
 if False:
diff --git a/icetime/timings.py b/icetime/timings.py
new file mode 100644
index 0000000..e559338
--- /dev/null
+++ b/icetime/timings.py
@@ -0,0 +1,49 @@
+#!/usr/bin/env python3
+
+import re
+
+print("// auto-generated by timings.py from ../icefuzz/timings_*.txt")
+
+def timings_to_c(chip, f):
+    print("")
+    print("double get_delay_%s(std::string cell_type, std::string in_port, std::string out_port)" % chip)
+    print("{")
+
+    in_cell = False
+
+    for line in f:
+        fields = line.split()
+        if len(fields) == 0:
+            continue
+
+        if fields[0] == "CELL":
+            if in_cell:
+                print("  }")
+            print("  if (cell_type == \"%s\") {" % fields[1])
+            in_cell = True
+
+        if fields[0] == "SETUP":
+            inport = fields[1].split(":")[1]
+            delay = max([0 if s == "*" else float(s) / 1000 for s in fields[3].split(":")])
+            print("    if (in_port == \"%s\" && out_port == \"*setup*\") return %.5f;" % (inport, delay))
+
+        if fields[0] == "IOPATH":
+            if fields[1].startswith("posedge:") or fields[1].startswith("negedge:"):
+                fields[1] = "*clkedge*"
+            delay = max([0 if s == "*" else float(s) / 1000 for s in fields[3].split(":") + fields[4].split(":")])
+            print("    if (in_port == \"%s\" && out_port == \"%s\") return %.5f;" % (fields[1], fields[2], delay))
+
+
+    if in_cell:
+        print("  }")
+    print("  if (in_port == \"*clkedge*\"|| out_port == \"*setup*\") return 0;")
+    print("  fprintf(stderr, \"Unable to resolve delay for path %s -> %s in cell type %s!\\n\", in_port.c_str(), out_port.c_str(), cell_type.c_str());")
+    print("  exit(1);")
+    print("}")
+
+with open("../icefuzz/timings_1k.txt", "r") as f:
+    timings_to_c("1k", f);
+
+with open("../icefuzz/timings_8k.txt", "r") as f:
+    timings_to_c("8k", f);
+