cost: add div, mod

kernel/cost.cc

@@ -90,6 +90,7 @@ static unsigned int max_inp_coef(RTLIL::IdString type)
 	// clang-format on
 	return 0;
 }
+
 static unsigned int sum_coef(RTLIL::IdString type)
 {
 	// clang-format off
@@ -106,6 +107,11 @@ static unsigned int sum_coef(RTLIL::IdString type)
 	return 0;
 }
 
+static unsigned int is_div_mod(RTLIL::IdString type)
+{
+	return (type == ID($div) || type == ID($divfloor) || type == ID($mod) || type == ID($modfloor));
+}
+
 static bool is_free(RTLIL::IdString type)
 {
 	// clang-format off
@@ -142,6 +148,36 @@ static bool is_free(RTLIL::IdString type)
 	// clang-format on
 }
 
+unsigned int max_inp_width(RTLIL::Cell *cell)
+{
+	unsigned int max = 0;
+	RTLIL::IdString input_width_params[] = {
+	  ID::WIDTH,
+	  ID::A_WIDTH,
+	  ID::B_WIDTH,
+	  ID::S_WIDTH,
+	};
+
+	for (RTLIL::IdString param : input_width_params)
+		if (cell->hasParam(param))
+			max = std::max(max, (unsigned int)cell->getParam(param).as_int());
+	return max;
+}
+
+unsigned int port_width_sum(RTLIL::Cell *cell)
+{
+	unsigned int sum = 0;
+	RTLIL::IdString port_width_params[] = {
+	  ID::WIDTH, ID::A_WIDTH, ID::B_WIDTH, ID::S_WIDTH, ID::Y_WIDTH,
+	};
+
+	for (auto param : port_width_params)
+		if (cell->hasParam(param))
+			sum += cell->getParam(param).as_int();
+
+	return sum;
+}
+
 unsigned int CellCosts::get(RTLIL::Cell *cell)
 {
 
@@ -164,33 +200,19 @@ unsigned int CellCosts::get(RTLIL::Cell *cell)
 		return width * y_coef(cell->type);
 	} else if (sum_coef(cell->type)) {
 		// linear with sum of port widths
-		unsigned int sum = 0;
-		RTLIL::IdString port_width_params[] = {
-		  ID::WIDTH, ID::A_WIDTH, ID::B_WIDTH, ID::S_WIDTH, ID::Y_WIDTH,
-		};
-
-		for (auto param : port_width_params)
-			if (cell->hasParam(param))
-				sum += cell->getParam(param).as_int();
-
+		unsigned int sum = port_width_sum(cell);
 		log_debug("%s sum*coef %d * %d\n", cell->name.c_str(), sum, sum_coef(cell->type));
 		return sum * sum_coef(cell->type);
 	} else if (max_inp_coef(cell->type)) {
 		// linear with largest input width
-		unsigned int max = 0;
-		RTLIL::IdString input_width_params[] = {
-		  ID::WIDTH,
-		  ID::A_WIDTH,
-		  ID::B_WIDTH,
-		  ID::S_WIDTH,
-		};
-
-		for (RTLIL::IdString param : input_width_params)
-			if (cell->hasParam(param))
-				max = std::max(max, (unsigned int)cell->getParam(param).as_int());
-
+		unsigned int max = max_inp_width(cell);
 		log_debug("%s max*coef %d * %d\n", cell->name.c_str(), max, max_inp_coef(cell->type));
-		return max;
+		return max * max_inp_coef(cell->type);
+	} else if (is_div_mod(cell->type)) {
+		// quadratic with sum of port widths
+		int sum = port_width_sum(cell);
+        log_debug("%s coef*(sum**2) 5 * %d\n", cell->name.c_str(), sum * sum);
+		return 5 * sum * sum;
 	} else if (is_free(cell->type)) {
 		log_debug("%s is free\n", cell->name.c_str());
 		return 0;