Support for SystemVerilog interfaces as a port in the top level module + test case

frontends/ast/ast.cc

@@ -904,7 +904,7 @@ RTLIL::Const AstNode::realAsConst(int width)
 }
 
 // create a new AstModule from an AST_MODULE AST node
-static AstModule* process_module(AstNode *ast, bool defer)
+static AstModule* process_module(AstNode *ast, bool defer, AstNode *original_ast = NULL)
 {
 	log_assert(ast->type == AST_MODULE || ast->type == AST_INTERFACE);
 
@@ -920,7 +920,11 @@ static AstModule* process_module(AstNode *ast, bool defer)
 	current_module->set_bool_attribute("\\cells_not_processed");
 
 	current_ast_mod = ast;
-	AstNode *ast_before_simplify = ast->clone();
+	AstNode *ast_before_simplify;
+	if (original_ast != NULL)
+		ast_before_simplify = original_ast;
+	else
+		ast_before_simplify = ast->clone();
 
 	if (flag_dump_ast1) {
 		log("Dumping Verilog AST before simplification:\n");
@@ -1105,6 +1109,104 @@ void AstModule::reprocess_module(RTLIL::Design *design, dict<RTLIL::IdString, RT
 		}
 	}
 
+	AstNode *ast_before_replacing_interface_ports = new_ast->clone();
+
+	// Explode all interface ports. Note this will only have any effect on top
+	// level modules. Other sub-modules will have their interface ports
+	// exploded in derive(..)
+	for (size_t i =0; i<new_ast->children.size(); i++)
+	{
+		AstNode *ch2 = new_ast->children[i];
+		std::string interface_type = "";
+		std::string interface_modport = "";
+		if (ch2->type == AST_INTERFACEPORT) {
+			std::string name_port = ch2->str;
+			if (ch2->children.size() > 0) {
+				for(size_t j=0; j<ch2->children.size();j++) {
+					AstNode *ch = ch2->children[j];
+					if(ch->type == AST_INTERFACEPORTTYPE) {
+						std::string name_type = ch->str;
+						size_t ndots = std::count(name_type.begin(), name_type.end(), '.');
+						// Separate the interface instance name from any modports:
+						if (ndots == 0) { // Does not have modport
+							interface_type = name_type;
+						}
+						else {
+							std::stringstream name_type_stream(name_type);
+							std::string segment;
+							std::vector<std::string> seglist;
+							while(std::getline(name_type_stream, segment, '.')) {
+								seglist.push_back(segment);
+							}
+							if (ndots == 1) { // Has modport
+								interface_type = seglist[0];
+								interface_modport = seglist[1];
+							}
+							else { // Erroneous port type
+								log_error("More than two '.' in signal port type (%s)\n", name_type.c_str());
+							}
+						}
+						if (design->modules_.count(interface_type) > 0) {
+							AstNode *celltype_for_intf = new AstNode(AST_CELLTYPE);
+							celltype_for_intf->str = interface_type;
+							AstNode *cell_for_intf = new AstNode(AST_CELL, celltype_for_intf);
+							cell_for_intf->str = name_port + "_inst_from_top_dummy";
+							new_ast->children.push_back(cell_for_intf);
+
+							RTLIL::Module *intfmodule = design->modules_[interface_type];
+							AstModule *ast_module_of_interface = (AstModule*)intfmodule;
+							AstNode *ast_node_of_interface = ast_module_of_interface->ast;
+							AstNode *modport = NULL;
+							std::string interface_modport_compare_str = "\\" + interface_modport;
+							for (auto &chm : ast_node_of_interface->children) {
+								if (chm->type == AST_MODPORT) {
+									if (chm->str == interface_modport_compare_str) { // Modport found
+										modport = chm;
+									}
+								}
+							}
+
+							std::string intfname = name_port;
+							for (auto &wire_it : intfmodule->wires_){
+								AstNode *wire = new AstNode(AST_WIRE, new AstNode(AST_RANGE, AstNode::mkconst_int(wire_it.second->width -1, true), AstNode::mkconst_int(0, true)));
+								std::string origname = log_id(wire_it.first);
+								std::string newname = intfname + "." + origname;
+								wire->str = newname;
+								if (modport != NULL) {
+									bool found_in_modport = false;
+									// Search for the current wire in the wire list for the current modport
+									for (auto &ch : modport->children) {
+										if (ch->type == AST_MODPORTMEMBER) {
+											std::string compare_name = "\\" + origname;
+											if (ch->str == compare_name) { // Found signal. The modport decides whether it is input or output
+												found_in_modport = true;
+												wire->is_input = ch->is_input;
+												wire->is_output = ch->is_output;
+												break;
+											}
+										}
+									}
+									if (found_in_modport) {
+										new_ast->children.push_back(wire);
+									}
+									else { // If not found in modport, do not create port
+										delete wire;
+									}
+								}
+								else { // If no modport, set inout
+									wire->is_input = true;
+									wire->is_output = true;
+									new_ast->children.push_back(wire);
+								}
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+
+
 	// The old module will be deleted. Rename and mark for deletion:
 	std::string original_name = this->name.str();
 	std::string changed_name = original_name + "_before_replacing_local_interfaces";
@@ -1119,7 +1221,7 @@ void AstModule::reprocess_module(RTLIL::Design *design, dict<RTLIL::IdString, RT
 	}
 
 	// Generate RTLIL from AST for the new module and add to the design:
-	AstModule *newmod = process_module(new_ast, false);
+	AstModule *newmod = process_module(new_ast, false, ast_before_replacing_interface_ports);
 	delete(new_ast);
 	design->add(newmod);
 	RTLIL::Module* mod = design->module(original_name);