diff --git a/ivl.def b/ivl.def
index 801c966e4..086d50b26 100644
--- a/ivl.def
+++ b/ivl.def
@@ -288,6 +288,7 @@ ivl_udp_file
 ivl_udp_lineno
 ivl_udp_name
 ivl_udp_nin
+ivl_udp_port
 ivl_udp_row
 ivl_udp_rows
 ivl_udp_sequ
diff --git a/ivl_target.h b/ivl_target.h
index deb046635..fcde050c5 100644
--- a/ivl_target.h
+++ b/ivl_target.h
@@ -1040,6 +1040,7 @@ extern unsigned    ivl_udp_rows(ivl_udp_t net);
 extern const char* ivl_udp_name(ivl_udp_t net);
 extern const char* ivl_udp_file(ivl_udp_t net);
 extern unsigned    ivl_udp_lineno(ivl_udp_t net);
+extern const char* ivl_udp_port(ivl_udp_t net, unsigned idx);
 
 extern const char* ivl_lpm_file(ivl_lpm_t net);
 extern unsigned    ivl_lpm_lineno(ivl_lpm_t net);
diff --git a/net_udp.cc b/net_udp.cc
index a2d7aa3d0..e9ca4e0bd 100644
--- a/net_udp.cc
+++ b/net_udp.cc
@@ -79,3 +79,14 @@ char NetUDP::get_initial() const
       assert(0);
       return 'x';
 }
+
+unsigned NetUDP::port_count() const
+{
+      return udp->ports.count();
+}
+
+string NetUDP::port_name(unsigned idx) const
+{
+      assert(idx < udp->ports.count());
+      return udp->ports[idx];
+}
diff --git a/netlist.h b/netlist.h
index 403ad6a4a..51fc92dd1 100644
--- a/netlist.h
+++ b/netlist.h
@@ -42,6 +42,7 @@
 # include  "LineInfo.h"
 # include  "svector.h"
 # include  "Attrib.h"
+# include  "PUdp.h"
 
 #ifdef HAVE_IOSFWD
 # include  <iosfwd>
@@ -2144,7 +2145,6 @@ class NetUReduce  : public NetNode {
  * 1 are listed.
  *
  */
-#include "PUdp.h"
 
 class NetUDP  : public NetNode {
 
@@ -2169,6 +2169,9 @@ class NetUDP  : public NetNode {
       unsigned udp_lineno() const { return udp->get_lineno(); }
       char get_initial() const;
 
+      unsigned port_count() const;
+      string port_name(unsigned idx) const;
+
     private:
       mutable unsigned table_idx;
       PUdp *udp;
diff --git a/t-dll-api.cc b/t-dll-api.cc
index 37c0255c4..49a640c19 100644
--- a/t-dll-api.cc
+++ b/t-dll-api.cc
@@ -867,6 +867,14 @@ extern "C" char ivl_udp_init(ivl_udp_t net)
       return net->init;
 }
 
+extern "C" const char* ivl_udp_port(ivl_udp_t net, unsigned idx)
+{
+      assert(idx <= net->nin);
+      assert(net->ports);
+      assert(net->ports[idx].c_str());
+      return net->ports[idx].c_str();
+}
+
 extern "C" const char* ivl_udp_row(ivl_udp_t net, unsigned idx)
 {
       assert(idx < net->nrows);
diff --git a/t-dll.cc b/t-dll.cc
index 1141626d8..2ae7b0c93 100644
--- a/t-dll.cc
+++ b/t-dll.cc
@@ -1270,38 +1270,36 @@ void dll_target::udp(const NetUDP*net)
       static map<perm_string,ivl_udp_t> udps;
       ivl_udp_t u;
 
-      if (udps.find(net->udp_name()) != udps.end())
-	{
-	  u = udps[net->udp_name()];
-	}
-      else
-	{
-	  u = new struct ivl_udp_s;
-	  u->nrows = net->rows();
-	  u->table = (ivl_udp_s::ccharp_t*)malloc((u->nrows+1)*sizeof(char*));
-	  u->table[u->nrows] = 0x0;
-	  u->nin = net->nin();
-	  u->sequ = net->is_sequential();
-	  u->file = net->udp_file();
-	  u->lineno = net->udp_lineno();
-	  if (u->sequ)
-	    u->init = net->get_initial();
-	  else
-	    u->init = 'x';
-	  u->name = net->udp_name();
-	  string inp;
-	  char out;
-	  unsigned int i = 0;
-	  if (net->first(inp, out))
-	    do
-	      {
-		string tt = inp+out;
-		u->table[i++] = strings_.add(tt.c_str());
-	      } while (net->next(inp, out));
-	  assert(i==u->nrows);
+      if (udps.find(net->udp_name()) != udps.end()) {
+	    u = udps[net->udp_name()];
+      } else {
+	    u = new struct ivl_udp_s;
+	    u->nrows = net->rows();
+	    u->table = (ivl_udp_s::ccharp_t*)malloc((u->nrows+1)*sizeof(char*));
+	    u->table[u->nrows] = 0x0;
+	    u->nin = net->nin();
+	    u->sequ = net->is_sequential();
+	    u->file = net->udp_file();
+	    u->lineno = net->udp_lineno();
+	    if (u->sequ) u->init = net->get_initial();
+	    else u->init = 'x';
+	    u->name = net->udp_name();
+	    string inp;
+	    char out;
+	    unsigned int i = 0;
+	    if (net->first(inp, out)) do {
+		  string tt = inp+out;
+		  u->table[i++] = strings_.add(tt.c_str());
+	    } while (net->next(inp, out));
+	    assert(i==u->nrows);
+	    assert((u->nin + 1) == net->port_count());
+	    u->ports = new string [u->nin + 1];
+	    for(unsigned idx = 0; idx <= u->nin; idx += 1) {
+		  u->ports[idx] = net->port_name(idx);
+	    }
 
-	  udps[net->udp_name()] = u;
-	}
+	    udps[net->udp_name()] = u;
+      }
 
       obj->udp = u;
 
diff --git a/t-dll.h b/t-dll.h
index 56aae7b02..0ff28e3da 100644
--- a/t-dll.h
+++ b/t-dll.h
@@ -517,6 +517,7 @@ struct ivl_udp_s {
       ccharp_t*table; // zero terminated array of pointers
       perm_string file;
       unsigned lineno;
+      string*ports;
 };
 
 /*