Merge pull request #1241 from YosysHQ/clifford/jsonfix

Improved JSON attr/param encoding

2 files changed, 71 insertions, 36 deletions

diff --git a/backends/json/json.cc b/backends/json/json.cc
index dda4dfedd..107009ee4 100644
--- a/backends/json/json.cc
+++ b/backends/json/json.cc
@@ -83,20 +83,43 @@ struct JsonWriter
 		return str + " ]";
 	}
 
+	void write_parameter_value(const Const &value)
+	{
+		if ((value.flags & RTLIL::ConstFlags::CONST_FLAG_STRING) != 0) {
+			string str = value.decode_string();
+			int state = 0;
+			for (char c : str) {
+				if (state == 0) {
+					if (c == '0' || c == '1' || c == 'x' || c == 'z')
+						state = 0;
+					else if (c == ' ')
+						state = 1;
+					else
+						state = 2;
+				} else if (state == 1 && c != ' ')
+					state = 2;
+			}
+			if (state < 2)
+				str += " ";
+			f << get_string(str);
+		} else
+		if (GetSize(value) == 32 && value.is_fully_def()) {
+			if ((value.flags & RTLIL::ConstFlags::CONST_FLAG_SIGNED) != 0)
+				f << stringf("%d", value.as_int());
+			else
+				f << stringf("%u", value.as_int());
+		} else {
+			f << get_string(value.as_string());
+		}
+	}
+
 	void write_parameters(const dict<IdString, Const> &parameters, bool for_module=false)
 	{
 		bool first = true;
 		for (auto &param : parameters) {
 			f << stringf("%s\n", first ? "" : ",");
 			f << stringf("        %s%s: ", for_module ? "" : "    ", get_name(param.first).c_str());
-			if ((param.second.flags & RTLIL::ConstFlags::CONST_FLAG_STRING) != 0)
-				f << get_string(param.second.decode_string());
-			else if (GetSize(param.second.bits) > 32)
-				f << get_string(param.second.as_string());
-			else if ((param.second.flags & RTLIL::ConstFlags::CONST_FLAG_SIGNED) != 0)
-				f << stringf("%d", param.second.as_int());
-			else
-				f << stringf("%u", param.second.as_int());
+			write_parameter_value(param.second);
 			first = false;
 		}
 	}
@@ -342,12 +365,13 @@ struct JsonBackend : public Backend {
 		log("Module and cell ports and nets can be single bit wide or vectors of multiple\n");
 		log("bits. Each individual signal bit is assigned a unique integer. The <bit_vector>\n");
 		log("values referenced above are vectors of this integers. Signal bits that are\n");
-		log("connected to a constant driver are denoted as string \"0\" or \"1\" instead of\n");
-		log("a number.\n");
+		log("connected to a constant driver are denoted as string \"0\", \"1\", \"x\", or\n");
+		log("\"z\" instead of a number.\n");
 		log("\n");
-		log("Numeric parameter and attribute values up to 32 bits are written as decimal\n");
-		log("values. Numbers larger than that are written as string holding the binary\n");
-		log("representation of the value.\n");
+		log("Numeric 32-bit parameter and attribute values are written as decimal values.\n");
+		log("Bit verctors of different sizes, or ones containing 'x' or 'z' bits, are written\n");
+		log("as string holding the binary representation of the value. Strings are written\n");
+		log("as strings, with an appended blank in cases of strings of the form /[01xz]* */.\n");
 		log("\n");
 		log("For example the following Verilog code:\n");
 		log("\n");
diff --git a/frontends/json/jsonparse.cc b/frontends/json/jsonparse.cc
index f5ae8eb72..7aceffbfc 100644
--- a/frontends/json/jsonparse.cc
+++ b/frontends/json/jsonparse.cc
@@ -25,7 +25,7 @@ struct JsonNode
 {
 	char type; // S=String, N=Number, A=Array, D=Dict
 	string data_string;
-	int data_number;
+	int64_t data_number;
 	vector<JsonNode*> data_array;
 	dict<string, JsonNode*> data_dict;
 	vector<string> data_dict_keys;
@@ -206,6 +206,38 @@ struct JsonNode
 	}
 };
 
+Const json_parse_attr_param_value(JsonNode *node)
+{
+	Const value;
+
+	if (node->type == 'S') {
+		string &s = node->data_string;
+		size_t cursor = s.find_first_not_of("01xz");
+		if (cursor == string::npos) {
+			value = Const::from_string(s);
+		} else if (s.find_first_not_of(' ', cursor) == string::npos) {
+			value = Const(s.substr(0, GetSize(s)-1));
+		} else {
+			value = Const(s);
+		}
+	} else
+	if (node->type == 'N') {
+		value = Const(node->data_number, 32);
+		if (node->data_number < 0)
+			value.flags |= RTLIL::CONST_FLAG_SIGNED;
+	} else
+	if (node->type == 'A') {
+		log_error("JSON attribute or parameter value is an array.\n");
+	} else
+	if (node->type == 'D') {
+		log_error("JSON attribute or parameter value is a dict.\n");
+	} else {
+		log_abort();
+	}
+
+	return value;
+}
+
 void json_parse_attr_param(dict<IdString, Const> &results, JsonNode *node)
 {
 	if (node->type != 'D')
@@ -214,28 +246,7 @@ void json_parse_attr_param(dict<IdString, Const> &results, JsonNode *node)
 	for (auto it : node->data_dict)
 	{
 		IdString key = RTLIL::escape_id(it.first.c_str());
-		JsonNode *value_node = it.second;
-		Const value;
-
-		if (value_node->type == 'S') {
-			string &s = value_node->data_string;
-			if (s.find_first_not_of("01xz") == string::npos)
-				value = Const::from_string(s);
-			else
-				value = Const(s);
-		} else
-		if (value_node->type == 'N') {
-			value = Const(value_node->data_number, 32);
-		} else
-		if (value_node->type == 'A') {
-			log_error("JSON attribute or parameter value is an array.\n");
-		} else
-		if (value_node->type == 'D') {
-			log_error("JSON attribute or parameter value is a dict.\n");
-		} else {
-			log_abort();
-		}
-
+		Const value = json_parse_attr_param_value(it.second);
 		results[key] = value;
 	}
 }