1 files changed, 36 insertions, 4 deletions

diff --git a/frontends/ast/ast.cc b/frontends/ast/ast.cc
index 256c08776..10fd5277a 100644
--- a/frontends/ast/ast.cc
+++ b/frontends/ast/ast.cc
@@ -1118,7 +1118,7 @@ void AstModule::reprocess_module(RTLIL::Design *design, dict<RTLIL::IdString, RT
 }
 
 // create a new parametric module (when needed) and return the name of the generated module - WITH support for interfaces
-RTLIL::IdString AstModule::derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters, dict<RTLIL::IdString, RTLIL::Module*> interfaces, bool mayfail)
+RTLIL::IdString AstModule::derive(RTLIL::Design *design, dict<RTLIL::IdString, RTLIL::Const> parameters, dict<RTLIL::IdString, RTLIL::Module*> interfaces, dict<RTLIL::IdString, RTLIL::IdString> modports, bool mayfail)
 {
 	AstNode *new_ast = NULL;
 	std::string modname = derive_common(design, parameters, &new_ast, mayfail);
@@ -1143,14 +1143,46 @@ RTLIL::IdString AstModule::derive(RTLIL::Design *design, dict<RTLIL::IdString, R
 		for(auto &intf : interfaces) {
 			RTLIL::Module * intfmodule = intf.second;
 			std::string intfname = intf.first.str();
+			AstNode *modport = NULL;
+			if (modports.count(intfname) > 0) {
+				std::string interface_modport = modports.at(intfname).str();
+				AstModule *ast_module_of_interface = (AstModule*)intfmodule;
+				AstNode *ast_node_of_interface = ast_module_of_interface->ast;
+				for (auto &ch : ast_node_of_interface->children) {
+					if (ch->type == AST_MODPORT) {
+						if (ch->str == interface_modport) {
+							modport = ch;
+						}
+					}
+				}
+			}
 			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;
-				wire->is_input = true;
-				wire->is_output = true;
-				new_ast->children.push_back(wire);
+				if (modport != NULL) {
+					bool found_in_modport = false;
+					for (auto &ch : modport->children) {
+						if (ch->type == AST_MODPORTMEMBER) {
+							std::string compare_name = "\\" + origname;
+							if (ch->str == compare_name) {
+								found_in_modport = true;
+								wire->is_input = ch->is_input;
+								wire->is_output = ch->is_output;
+								break;
+							}
+						}
+					}
+					if (found_in_modport) { // If not found in modport, do not create port
+						new_ast->children.push_back(wire);
+					}
+				}
+				else { // If no modport, set inout
+					wire->is_input = true;
+					wire->is_output = true;
+					new_ast->children.push_back(wire);
+				}
 			}
 		}