diff --git a/tgt-vhdl/scope.cc b/tgt-vhdl/scope.cc
index faaadde83..b5a7de94d 100644
--- a/tgt-vhdl/scope.cc
+++ b/tgt-vhdl/scope.cc
@@ -401,12 +401,18 @@ int draw_function(ivl_scope_t scope, ivl_scope_t parent)
       std::string signame = make_safe_name(sig);
 
       vhdl_type *sigtype = get_signal_type(sig);
-      if (ivl_signal_type(sig) == IVL_SIT_REG) {
+
+      switch (ivl_signal_port(sig)) {
+      case IVL_SIP_OUTPUT:
+         assert(func == NULL);
          func = new vhdl_function(funcname, sigtype);
-         
-      }
-      else {
+         break;
+      case IVL_SIP_INPUT:
          assert(func);
+         func->add_param(new vhdl_param_decl(signame.c_str(), sigtype));
+         break;
+      default:
+         assert(false);
       }
 
       remember_signal(sig, func->get_scope());
diff --git a/tgt-vhdl/vhdl_syntax.cc b/tgt-vhdl/vhdl_syntax.cc
index d8bdb95ed..4825b94e5 100644
--- a/tgt-vhdl/vhdl_syntax.cc
+++ b/tgt-vhdl/vhdl_syntax.cc
@@ -765,10 +765,10 @@ vhdl_function::vhdl_function(const char *name, vhdl_type *ret_type)
 void vhdl_function::emit(std::ofstream &of, int level) const
 {
    of << "function " << name_ << " (";
-   emit_children<vhdl_decl>(of, scope_.get_decls(), level, ",");
-   of << ") return ";
-   type_->emit(of, level);
-   of << " is";
+   emit_children<vhdl_decl>(of, scope_.get_decls(), level, ";");
+   of << ") ";
+   newline(of, level);
+   of << "return " << type_->get_string() << " is";
    emit_children<vhdl_decl>(of, variables_.get_decls(), level);
    of << "begin";
    stmts_.emit(of, level);