diff --git a/Makefile.in b/Makefile.in
index c3a506d68..f5de24c36 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -16,7 +16,7 @@
 #    59 Temple Place - Suite 330
 #    Boston, MA 02111-1307, USA
 #
-#ident "$Id: Makefile.in,v 1.115 2002/02/16 03:18:53 steve Exp $"
+#ident "$Id: Makefile.in,v 1.116 2002/03/09 02:10:22 steve Exp $"
 #
 #
 SHELL = /bin/sh
@@ -126,7 +126,8 @@ elab_lval.o elab_net.o elab_anet.o elab_pexpr.o elab_scope.o \
 elab_sig.o emit.o eval.o eval_rconst.o \
 eval_tree.o expr_synth.o functor.o lexor.o lexor_keyword.o link_const.o \
 load_module.o mangle.o netlist.o netmisc.o net_assign.o \
-net_design.o net_event.o net_expr.o net_force.o net_link.o net_modulo.o \
+net_design.o net_event.o net_expr.o net_force.o net_func.o \
+net_link.o net_modulo.o \
 net_proc.o net_scope.o net_udp.o pad_to_width.o \
 parse.o parse_misc.o pform.o pform_dump.o \
 set_width.o \
diff --git a/PExpr.h b/PExpr.h
index 528fcac82..86e0e4df0 100644
--- a/PExpr.h
+++ b/PExpr.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: PExpr.h,v 1.54 2001/12/30 21:32:03 steve Exp $"
+#ident "$Id: PExpr.h,v 1.55 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include  <string>
@@ -443,7 +443,8 @@ class PETernary : public PExpr {
 
 /*
  * This class represents a parsed call to a function, including calls
- * to system functions.
+ * to system functions. The parameters in the parms list are the
+ * expressions that are passed as input to the ports of the function.
  */
 class PECallFunction : public PExpr {
     public:
@@ -452,17 +453,29 @@ class PECallFunction : public PExpr {
       ~PECallFunction();
 
       virtual void dump(ostream &) const;
+      virtual NetNet* elaborate_net(Design*des, NetScope*scope,
+				    unsigned width,
+				    unsigned long rise,
+				    unsigned long fall,
+				    unsigned long decay,
+				    Link::strength_t drive0,
+				    Link::strength_t drive1) const;
       virtual NetExpr*elaborate_expr(Design*des, NetScope*scope) const;
 
     private:
       hname_t path_;
       svector<PExpr *> parms_;
 
+      bool check_call_matches_definition_(Design*des, NetScope*dscope) const;
+
       NetExpr* elaborate_sfunc_(Design*des, NetScope*scope) const;
 };
 
 /*
  * $Log: PExpr.h,v $
+ * Revision 1.55  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.54  2001/12/30 21:32:03  steve
  *  Support elaborate_net for PEString objects.
  *
diff --git a/design_dump.cc b/design_dump.cc
index c522877a8..c568d8cb6 100644
--- a/design_dump.cc
+++ b/design_dump.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: design_dump.cc,v 1.121 2001/12/31 00:03:05 steve Exp $"
+#ident "$Id: design_dump.cc,v 1.122 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -353,6 +353,14 @@ void NetRamDq::dump_node(ostream&o, unsigned ind) const
       dump_obj_attr(o, ind+4);
 }
 
+void NetUserFunc::dump_node(ostream&o, unsigned ind) const
+{
+      o << setw(ind) << "" << def_->name() << "(";
+      o << ")" << endl;
+      dump_node_pins(o, ind+4);
+      dump_obj_attr(o, ind+4);
+}
+
 void NetTaskDef::dump(ostream&o, unsigned ind) const
 {
       o << setw(ind) << "" << "task " << name_ << ";" << endl;
@@ -972,6 +980,9 @@ void Design::dump(ostream&o) const
 
 /*
  * $Log: design_dump.cc,v $
+ * Revision 1.122  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.121  2001/12/31 00:03:05  steve
  *  Include s indicator in dump of signed numbers.
  *
diff --git a/elab_expr.cc b/elab_expr.cc
index d7bced28e..c471a4894 100644
--- a/elab_expr.cc
+++ b/elab_expr.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: elab_expr.cc,v 1.50 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: elab_expr.cc,v 1.51 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -258,30 +258,14 @@ NetExpr* PECallFunction::elaborate_expr(Design*des, NetScope*scope) const
       NetScope*dscope = def->scope();
       assert(dscope);
 
-	/* How many parameters have I got? Normally the size of the
-	   list is correct, but there is the special case of a list of
-	   1 nil pointer. This is how the parser tells me of no
-	   parameter. In other words, ``func()'' is 1 nil parameter. */
+      if (! check_call_matches_definition_(des, dscope))
+	    return 0;
 
       unsigned parms_count = parms_.count();
       if ((parms_count == 1) && (parms_[0] == 0))
 	    parms_count = 0;
 
-      if (dscope->type() != NetScope::FUNC) {
-	    cerr << get_line() << ": error: Attempt to call scope "
-		 << dscope->name() << " as a function." << endl;
-	    des->errors += 1;
-	    return 0;
-      }
-
-      if ((parms_count+1) != dscope->func_def()->port_count()) {
-	    cerr << get_line() << ": error: Function " << dscope->name()
-		 << " expects " << (dscope->func_def()->port_count()-1)
-		 << " parameters, you passed " << parms_count << "."
-		 << endl;
-	    des->errors += 1;
-	    return 0;
-      }
+      
 
       svector<NetExpr*> parms (parms_count);
 
@@ -690,6 +674,9 @@ NetEUnary* PEUnary::elaborate_expr(Design*des, NetScope*scope) const
 
 /*
  * $Log: elab_expr.cc,v $
+ * Revision 1.51  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.50  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
diff --git a/elab_net.cc b/elab_net.cc
index 043d00da9..9b19c86f1 100644
--- a/elab_net.cc
+++ b/elab_net.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: elab_net.cc,v 1.86 2002/01/23 05:23:17 steve Exp $"
+#ident "$Id: elab_net.cc,v 1.87 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -970,6 +970,95 @@ NetNet* PEBinary::elaborate_net_shift_(Design*des, NetScope*scope,
       return osig;
 }
 
+/*
+ * This method elaborates a call to a function in the context of a
+ * continuous assignment.
+ */
+NetNet* PECallFunction::elaborate_net(Design*des, NetScope*scope, unsigned,
+				      unsigned long,
+				      unsigned long,
+				      unsigned long,
+				      Link::strength_t,
+				      Link::strength_t) const
+{
+      unsigned errors = 0;
+      unsigned func_pins = 0;
+
+	/* Look up the function definition. */
+      NetFuncDef*def = des->find_function(scope, path_);
+      if (def == 0) {
+	    cerr << get_line() << ": error: No function " << path_ <<
+		  " in this context (" << scope->name() << ")." << endl;
+	    des->errors += 1;
+	    return 0;
+      }
+      assert(def);
+
+      NetScope*dscope = def->scope();
+      assert(dscope);
+
+	/* check the validity of the parameters. */
+      if (! check_call_matches_definition_(des, dscope))
+	    return 0;
+
+	/* Elaborate all the parameters of the function call,
+	   and collect the resulting NetNet objects. All the
+	   parameters take on the size of the target port. */
+
+      svector<NetNet*> eparms (def->port_count()-1);
+      for (unsigned idx = 0 ;  idx < eparms.count() ;  idx += 1) {
+	    const NetNet* port_reg = def->port(idx+1);
+	    NetNet*tmp = parms_[idx]->elaborate_net(des, scope,
+						    port_reg->pin_count(),
+						    0, 0, 0,
+						    Link::STRONG,
+						    Link::STRONG);
+	    if (tmp == 0) {
+		  cerr << get_line() << ": error: Unable to elaborate "
+		       << "port " << idx << " of call to " << path_ <<
+			"." << endl;
+		  errors += 1;
+		  continue;
+	    }
+
+	    func_pins += tmp->pin_count();
+	    eparms[idx] = tmp;
+      }
+
+      if (errors > 0)
+	    return 0;
+
+
+      NetUserFunc*net = new NetUserFunc(scope,
+					scope->local_hsymbol().c_str(),
+					dscope);
+      des->add_node(net);
+
+	/* Create an output signal and connect it to the output pins
+	   of the function net. */
+      NetNet*osig = new NetNet(scope, scope->local_hsymbol(),
+			       NetNet::WIRE,
+			       def->port(0)->pin_count());
+      osig->local_flag(true);
+
+      for (unsigned idx = 0 ;  idx < osig->pin_count() ;  idx += 1)
+	    connect(net->port_pin(0, idx), osig->pin(idx));
+
+	/* Connect the parameter pins to the parameter expressions. */
+      for (unsigned idx = 0 ; idx < eparms.count() ; idx += 1) {
+	    const NetNet* port = def->port(idx+1);
+	    NetNet*cur = eparms[idx];
+
+	    NetNet*tmp = pad_to_width(des, cur, port->pin_count());
+
+	    for (unsigned pin = 0 ;  pin < port->pin_count() ;  pin += 1)
+		  connect(net->port_pin(idx+1, pin), tmp->pin(pin));
+      }
+
+      return osig;
+}
+
+
 /*
  * The concatenation operator, as a net, is a wide signal that is
  * connected to all the pins of the elaborated expression nets.
@@ -1481,7 +1570,6 @@ NetNet* PEIdent::elaborate_port(Design*des, NetScope*scope) const
       return sig;
 }
 
-
 /*
  * Elaborate a number as a NetConst object.
  */
@@ -1974,6 +2062,9 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
 
 /*
  * $Log: elab_net.cc,v $
+ * Revision 1.87  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.86  2002/01/23 05:23:17  steve
  *  No implicit declaration in assign l-values.
  *
diff --git a/emit.cc b/emit.cc
index 76a0ae5d9..a232a182c 100644
--- a/emit.cc
+++ b/emit.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: emit.cc,v 1.65 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: emit.cc,v 1.66 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -128,6 +128,11 @@ bool NetRamDq::emit_node(struct target_t*tgt) const
       return true;
 }
 
+bool NetUserFunc::emit_node(struct target_t*tgt) const
+{
+      return tgt->net_function(this);
+}
+
 bool NetBUFZ::emit_node(struct target_t*tgt) const
 {
       return tgt->bufz(this);
@@ -482,6 +487,9 @@ bool emit(const Design*des, const char*type)
 
 /*
  * $Log: emit.cc,v $
+ * Revision 1.66  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.65  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
diff --git a/ivl_target.h b/ivl_target.h
index 54451ccbd..e7364a3e4 100644
--- a/ivl_target.h
+++ b/ivl_target.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: ivl_target.h,v 1.92 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: ivl_target.h,v 1.93 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 #ifdef __cplusplus
@@ -217,7 +217,8 @@ typedef enum ivl_lpm_type_e {
       IVL_LPM_SHIFTL =  6,
       IVL_LPM_SHIFTR =  7,
       IVL_LPM_SUB    =  8,
-      IVL_LPM_RAM    =  9
+      IVL_LPM_RAM    =  9,
+      IVL_LPM_UFUNC  = 14
 } ivl_lpm_type_t;
 
 /* Processes are initial or always blocks with a statement. This is
@@ -570,7 +571,8 @@ extern ivl_nexus_t ivl_lpm_data(ivl_lpm_t net, unsigned idx);
 extern ivl_nexus_t ivl_lpm_datab(ivl_lpm_t net, unsigned idx);
   /* IVL_LPM_MUX */
 extern ivl_nexus_t ivl_lpm_data2(ivl_lpm_t net, unsigned sdx, unsigned idx);
-  /* IVL_LPM_ADD IVL_LPM_FF IVL_LPM_MULT IVL_LPM_RAM IVL_LPM_SUB */
+  /* IVL_LPM_ADD IVL_LPM_FF IVL_LPM_MULT IVL_LPM_RAM IVL_LPM_SUB
+     IVL_LPM_UFUNC */
 extern ivl_nexus_t ivl_lpm_q(ivl_lpm_t net, unsigned idx);
   /* IVL_LPM_MUX IVL_LPM_RAM */
 extern unsigned ivl_lpm_selects(ivl_lpm_t net);
@@ -726,8 +728,25 @@ extern ivl_signal_t ivl_nexus_ptr_sig(ivl_nexus_ptr_t net);
  * generally when a module is instantiated, though they also come from
  * named blocks, tasks and functions.
  *
- * (NOTE: Module scopes are *instances* of modules, and not the module
- * definition. A definition may apply to many instances.)
+ * - module instances (IVL_SCT_MODULE)
+ *    A module instance scope may contain events, logic gates, lpm
+ *    nodes, signals, and possibly children. The children are further
+ *    instances, or function/task scopes. Module instances do *not*
+ *    contain a definition.
+ *
+ * - function scopes (IVL_SCT_FUNCTION)
+ *    These scopes represent functions. A function may not be a root,
+ *    so it is contained within a module instance scope. A function is
+ *    required to have a definition (in the form of a statement) and a
+ *    signal (IVL_SIG_REG) that is its return value.
+ *
+ *    A single function scope is created each time the module with the
+ *    definition is instantiated.
+ *
+ *
+ * - task scopes (IVL_SCT_TASK)
+ *    [...]
+ *
  *
  * ivl_scope_children
  *    A scope may in turn contain other scopes. This method iterates
@@ -752,6 +771,11 @@ extern ivl_signal_t ivl_nexus_ptr_sig(ivl_nexus_ptr_t net);
  *    Scopes have 0 or more logic devices in them. A logic device is
  *    represented by ivl_logic_t.
  *
+ * ivl_scope_lpm
+ * ivl_scope_lpms
+ *    Scopes have 0 or more LPM devices in them. These functions acess
+ *    those devices.
+ *
  * ivl_scope_name
  * ivl_scope_basename
  *    Every scope has a hierarchical name. This name is also a prefix
@@ -978,6 +1002,9 @@ _END_DECL
 
 /*
  * $Log: ivl_target.h,v $
+ * Revision 1.93  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.92  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
@@ -995,261 +1022,5 @@ _END_DECL
  *
  * Revision 1.88  2001/11/14 03:28:49  steve
  *  DLL target support for force and release.
- *
- * Revision 1.87  2001/11/01 04:25:31  steve
- *  ivl_target support for cassign.
- *
- * Revision 1.86  2001/10/31 05:24:52  steve
- *  ivl_target support for assign/deassign.
- *
- * Revision 1.85  2001/10/19 21:53:24  steve
- *  Support multiple root modules (Philip Blundell)
- *
- * Revision 1.84  2001/10/16 02:19:27  steve
- *  Support IVL_LPM_DIVIDE for structural divide.
- *
- * Revision 1.83  2001/09/30 16:45:10  steve
- *  Fix some Cygwin DLL handling. (Venkat Iyer)
- *
- * Revision 1.82  2001/09/16 22:19:42  steve
- *  Support attributes to logic gates.
- *
- * Revision 1.81  2001/09/09 22:21:57  steve
- *  pin down some enumerated constants.
- *
- * Revision 1.80  2001/09/01 01:57:31  steve
- *  Make constants available through the design root
- *
- * Revision 1.79  2001/08/31 22:58:39  steve
- *  Support DFF CE inputs.
- *
- * Revision 1.78  2001/08/28 04:07:17  steve
- *  Add some ivl_target convenience functions.
- *
- * Revision 1.77  2001/08/25 23:50:03  steve
- *  Change the NetAssign_ class to refer to the signal
- *  instead of link into the netlist. This is faster
- *  and uses less space. Make the NetAssignNB carry
- *  the delays instead of the NetAssign_ lval objects.
- *
- *  Change the vvp code generator to support multiple
- *  l-values, i.e. concatenations of part selects.
- *
- * Revision 1.76  2001/08/10 00:40:45  steve
- *  tgt-vvp generates code that skips nets as inputs.
- *
- * Revision 1.75  2001/07/27 04:51:44  steve
- *  Handle part select expressions as variants of
- *  NetESignal/IVL_EX_SIGNAL objects, instead of
- *  creating new and useless temporary signals.
- *
- * Revision 1.74  2001/07/27 02:41:55  steve
- *  Fix binding of dangling function ports. do not elide them.
- *
- * Revision 1.73  2001/07/22 00:17:49  steve
- *  Support the NetESubSignal expressions in vvp.tgt.
- *
- * Revision 1.72  2001/07/19 04:55:06  steve
- *  Support calculated delays in vvp.tgt.
- *
- * Revision 1.71  2001/07/04 22:59:25  steve
- *  handle left shifter in dll output.
- *
- * Revision 1.70  2001/06/30 23:03:16  steve
- *  support fast programming by only writing the bits
- *  that are listed in the input file.
- *
- * Revision 1.69  2001/06/19 03:01:10  steve
- *  Add structural EEQ gates (Stephan Boettcher)
- *
- * Revision 1.68  2001/06/16 23:45:05  steve
- *  Add support for structural multiply in t-dll.
- *  Add code generators and vvp support for both
- *  structural and behavioral multiply.
- *
- * Revision 1.67  2001/06/16 02:41:41  steve
- *  Generate code to support memory access in continuous
- *  assignment statements. (Stephan Boettcher)
- *
- * Revision 1.66  2001/06/15 04:14:18  steve
- *  Generate vvp code for GT and GE comparisons.
- *
- * Revision 1.65  2001/06/07 03:09:37  steve
- *  support subtraction in tgt-vvp.
- *
- * Revision 1.64  2001/06/07 02:12:43  steve
- *  Support structural addition.
- *
- * Revision 1.63  2001/05/20 01:06:16  steve
- *  stub ivl_expr_parms for sfunctions.
- *
- * Revision 1.62  2001/05/17 04:37:02  steve
- *  Behavioral ternary operators for vvp.
- *
- * Revision 1.61  2001/05/12 03:18:44  steve
- *  Make sure LPM devices have drives on outputs.
- *
- * Revision 1.60  2001/05/08 23:59:33  steve
- *  Add ivl and vvp.tgt support for memories in
- *  expressions and l-values. (Stephan Boettcher)
- *
- * Revision 1.59  2001/05/08 04:13:12  steve
- *  sort enumeration values.
- *
- * Revision 1.58  2001/05/06 17:48:20  steve
- *  Support memory objects. (Stephan Boettcher)
- *
- * Revision 1.57  2001/04/29 23:17:38  steve
- *  Carry drive strengths in the ivl_nexus_ptr_t, and
- *  handle constant devices in targets.'
- *
- * Revision 1.56  2001/04/29 20:19:10  steve
- *  Add pullup and pulldown devices.
- *
- * Revision 1.55  2001/04/26 05:12:02  steve
- *  Implement simple MUXZ for ?: operators.
- *
- * Revision 1.54  2001/04/22 23:09:46  steve
- *  More UDP consolidation from Stephan Boettcher.
- *
- * Revision 1.53  2001/04/21 00:55:46  steve
- *  Generate code for disable.
- *
- * Revision 1.52  2001/04/15 02:58:11  steve
- *  vvp support for <= with internal delay.
- *
- * Revision 1.51  2001/04/07 19:24:36  steve
- *  Add the disable statemnent.
- *
- * Revision 1.50  2001/04/06 02:28:02  steve
- *  Generate vvp code for functions with ports.
- *
- * Revision 1.49  2001/04/05 03:20:57  steve
- *  Generate vvp code for the repeat statement.
- *
- * Revision 1.48  2001/04/05 01:12:27  steve
- *  Get signed compares working correctly in vvp.
- *
- * Revision 1.47  2001/04/04 04:50:35  steve
- *  Support forever loops in the tgt-vvp target.
- *
- * Revision 1.46  2001/04/03 04:50:37  steve
- *  Support non-blocking assignments.
- *
- * Revision 1.45  2001/04/02 02:28:12  steve
- *  Generate code for task calls.
- *
- * Revision 1.44  2001/04/02 00:28:35  steve
- *  Support the scope expression node.
- *
- * Revision 1.43  2001/04/01 06:52:27  steve
- *  support the NetWhile statement.
- *
- * Revision 1.42  2001/04/01 04:38:17  steve
- *  dead cruft.
- *
- * Revision 1.41  2001/04/01 01:48:21  steve
- *  Redesign event information to support arbitrary edge combining.
- *
- * Revision 1.40  2001/03/31 17:36:38  steve
- *  Generate vvp code for case statements.
- *
- * Revision 1.39  2001/03/30 05:49:52  steve
- *  Generate code for fork/join statements.
- *
- * Revision 1.38  2001/03/29 02:52:39  steve
- *  Add unary ~ operator to tgt-vvp.
- *
- * Revision 1.37  2001/03/28 06:07:39  steve
- *  Add the ivl_event_t to ivl_target, and use that to generate
- *  .event statements in vvp way ahead of the thread that uses it.
- *
- * Revision 1.36  2001/03/27 06:27:40  steve
- *  Generate code for simple @ statements.
- *
- * Revision 1.35  2001/03/20 01:44:13  steve
- *  Put processes in the proper scope.
- *
- * Revision 1.34  2001/01/15 22:05:14  steve
- *  Declare ivl_scope_type functions.
- *
- * Revision 1.33  2001/01/15 00:47:01  steve
- *  Pass scope type information to the target module.
- *
- * Revision 1.32  2001/01/15 00:05:39  steve
- *  Add client data pointer for scope and process scanners.
- *
- * Revision 1.31  2001/01/06 06:31:58  steve
- *  declaration initialization for time variables.
- *
- * Revision 1.30  2000/12/05 06:29:33  steve
- *  Make signal attributes available to ivl_target API.
- *
- * Revision 1.29  2000/11/12 17:47:29  steve
- *  flip-flop pins for ivl_target API.
- *
- * Revision 1.28  2000/11/11 01:52:09  steve
- *  change set for support of nmos, pmos, rnmos, rpmos, notif0, and notif1
- *  change set to correct behavior of bufif0 and bufif1
- *  (Tim Leight)
- *
- *  Also includes fix for PR#27
- *
- * Revision 1.27  2000/11/11 00:03:36  steve
- *  Add support for the t-dll backend grabing flip-flops.
- *
- * Revision 1.26  2000/10/31 17:49:02  steve
- *  Support time variables.
- *
- * Revision 1.25  2000/10/28 22:32:34  steve
- *  API for concatenation expressions.
- *
- * Revision 1.24  2000/10/28 17:55:03  steve
- *  stub for the concat operator.
- *
- * Revision 1.23  2000/10/25 05:41:24  steve
- *  Get target signal from nexus_ptr.
- *
- * Revision 1.22  2000/10/21 16:49:45  steve
- *  Reduce the target entry points to the target_design.
- *
- * Revision 1.21  2000/10/18 20:04:39  steve
- *  Add ivl_lval_t and support for assignment l-values.
- *
- * Revision 1.20  2000/10/15 04:46:23  steve
- *  Scopes and processes are accessible randomly from
- *  the design, and signals and logic are accessible
- *  from scopes. Remove the target calls that are no
- *  longer needed.
- *
- *  Add the ivl_nexus_ptr_t and the means to get at
- *  them from nexus objects.
- *
- *  Give names to methods that manipulate the ivl_design_t
- *  type more consistent names.
- *
- * Revision 1.19  2000/10/13 03:39:27  steve
- *  Include constants in nexus targets.
- *
- * Revision 1.18  2000/10/08 04:01:54  steve
- *  Back pointers in the nexus objects into the devices
- *  that point to it.
- *
- *  Collect threads into a list in the design.
- *
- * Revision 1.17  2000/10/07 19:45:43  steve
- *  Put logic devices into scopes.
- *
- * Revision 1.16  2000/10/06 23:46:50  steve
- *  ivl_target updates, including more complete
- *  handling of ivl_nexus_t objects. Much reduced
- *  dependencies on pointers to netlist objects.
- *
- * Revision 1.15  2000/10/05 05:03:01  steve
- *  xor and constant devices.
- *
- * Revision 1.14  2000/09/30 02:18:15  steve
- *  ivl_expr_t support for binary operators,
- *  Create a proper ivl_scope_t object.
  */
 #endif
diff --git a/ivl_target.txt b/ivl_target.txt
new file mode 100644
index 000000000..f15ed97c1
--- /dev/null
+++ b/ivl_target.txt
@@ -0,0 +1,39 @@
+
+Icarus Verilog LOADABLE TARGET API (ivl_target)
+
+  Copyright 2002 Stephen Williams <steve@icarus.com>
+  $Id: ivl_target.txt,v 1.1 2002/03/09 02:10:22 steve Exp $
+
+
+The ivl_target API is the interface available to modules that the
+Icarus Verilog compiler loads to act as a code generator. The API
+provides an interface to the elaborated, possibly synthesized, design
+for code generators that are intended to write netlist files or
+executable programs.
+
+The functions and types of the API are summarized in the ivl_target.h
+header file. This ducument describes how the functions and types of
+the API are used to access and interpret the netlist of the design.
+
+
+LPM DEVICES
+
+All LPM devices support a small set of common LPM functions, as
+described in the ivl_target header file.
+
+* IVL_LPM_UFUNC
+
+This LPM represents a user defined function. It is a way to connect
+behavioral code into a structural network. The UFUNC device has a
+vector output and a set of inputs.
+
+The output vector is accessible through the ivl_lpm_q, and the output
+has the width defined by ivl_lpm_width. This similar to most every
+other LPM device with outputs.
+
+
+
+$Log: ivl_target.txt,v $
+Revision 1.1  2002/03/09 02:10:22  steve
+ Add the NetUserFunc netlist node.
+
diff --git a/net_func.cc b/net_func.cc
new file mode 100644
index 000000000..6a8ebbb6d
--- /dev/null
+++ b/net_func.cc
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2002 Stephen Williams (steve@icarus.com)
+ *
+ *    This source code is free software; you can redistribute it
+ *    and/or modify it in source code form under the terms of the GNU
+ *    General Public License as published by the Free Software
+ *    Foundation; either version 2 of the License, or (at your option)
+ *    any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+#if !defined(WINNT)
+#ident "$Id: net_func.cc,v 1.1 2002/03/09 02:10:22 steve Exp $"
+#endif
+
+# include  "netlist.h"
+# include  "PExpr.h"
+
+static unsigned count_def_pins(const NetFuncDef*def)
+{
+      unsigned sum = 0;
+      for (unsigned idx = 0 ;  idx < def->port_count() ;  idx += 1)
+	    sum += def->port(idx)->pin_count();
+
+      return sum;
+}
+
+NetUserFunc::NetUserFunc(NetScope*s, const char*n, NetScope*d)
+: NetNode(s, n, count_def_pins(d->func_def())), def_(d)
+{
+      NetFuncDef*def = def_->func_def();
+
+      unsigned port_wid = port_width(0);
+      for (unsigned idx = 0 ;  idx < port_wid ;  idx += 1) {
+	    pin(idx).set_dir(Link::OUTPUT);
+	    pin(idx).set_name(def_->basename(), idx);
+      }
+
+      unsigned pin_base = port_wid;
+      for (unsigned idx = 1 ;  idx < port_count() ;  idx += 1) {
+
+	    const NetNet*port_sig = def->port(idx);
+	    unsigned bits = port_width(idx);
+	    for (unsigned bit = 0; bit < bits; bit += 1) {
+		  pin(pin_base+bit).set_dir(Link::INPUT);
+		  pin(pin_base+bit).set_name(port_sig->name(), bit);
+		  pin(pin_base+bit).drive0(Link::HIGHZ);
+		  pin(pin_base+bit).drive1(Link::HIGHZ);
+	    }
+
+	    pin_base += bits;
+      }
+}
+
+NetUserFunc::~NetUserFunc()
+{
+}
+
+unsigned NetUserFunc::port_count() const
+{
+      return def_->func_def()->port_count();
+}
+
+unsigned NetUserFunc::port_width(unsigned port) const
+{
+      NetFuncDef*def = def_->func_def();
+
+      assert(port < def->port_count());
+      const NetNet*port_sig = def->port(port);
+
+      return port_sig->pin_count();
+}
+
+Link& NetUserFunc::port_pin(unsigned port, unsigned idx)
+{
+      NetFuncDef*def = def_->func_def();
+      unsigned pin_base = 0;
+      const NetNet*port_sig;
+
+      assert(port < def->port_count());
+
+      for (unsigned port_idx = 0 ;  port_idx < port ;  port_idx += 1) {
+	    port_sig = def->port(port_idx);
+	    pin_base += port_sig->pin_count();
+      }
+
+      port_sig = def->port(port);
+      assert(idx < port_sig->pin_count());
+      assert((pin_base+idx) < pin_count());
+
+      return pin(pin_base+idx);
+}
+
+
+const NetScope* NetUserFunc::def() const
+{
+      return def_;
+}
+
+/*
+ * This method of the PECallFunction class checks that the parameters
+ * of the PECallFunction match the function definition. This is used
+ * during elaboration to validate the parameters before using them.
+ */
+bool PECallFunction::check_call_matches_definition_(Design*des, NetScope*dscope) const
+{
+      assert(dscope);
+
+	/* How many parameters have I got? Normally the size of the
+	   list is correct, but there is the special case of a list of
+	   1 nil pointer. This is how the parser tells me of no
+	   parameter. In other words, ``func()'' is 1 nil parameter. */
+
+      unsigned parms_count = parms_.count();
+      if ((parms_count == 1) && (parms_[0] == 0))
+	    parms_count = 0;
+
+      if (dscope->type() != NetScope::FUNC) {
+	    cerr << get_line() << ": error: Attempt to call scope "
+		 << dscope->name() << " as a function." << endl;
+	    des->errors += 1;
+	    return false;
+      }
+
+      if ((parms_count+1) != dscope->func_def()->port_count()) {
+	    cerr << get_line() << ": error: Function " << dscope->name()
+		 << " expects " << (dscope->func_def()->port_count()-1)
+		 << " parameters, you passed " << parms_count << "."
+		 << endl;
+	    des->errors += 1;
+	    return false;
+      }
+
+      return true;
+}
+
+/*
+ * $Log: net_func.cc,v $
+ * Revision 1.1  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
+ */
+
diff --git a/netlist.h b/netlist.h
index e3d733d2c..f984b400c 100644
--- a/netlist.h
+++ b/netlist.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: netlist.h,v 1.231 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: netlist.h,v 1.232 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 /*
@@ -52,6 +52,7 @@ class NetProcTop;
 class NetScope;
 class NetExpr;
 class NetESignal;
+class NetFuncDef;
 
 
 struct target;
@@ -819,6 +820,29 @@ class NetRamDq  : public NetNode {
 
 };
 
+/*
+ * This node represents the call of a user defined function in a
+ * structural context.
+ */
+class NetUserFunc  : public NetNode {
+
+    public:
+      NetUserFunc(NetScope*s, const char*n, NetScope*def);
+      ~NetUserFunc();
+
+      unsigned port_count() const;
+      unsigned port_width(unsigned port) const;
+      Link& port_pin(unsigned port, unsigned idx);
+
+      const NetScope* def() const;
+
+      virtual void dump_node(ostream&, unsigned ind) const;
+      virtual bool emit_node(struct target_t*) const;
+
+    private:
+      NetScope*def_;
+};
+
 /* =========
  * There are cases where expressions need to be represented. The
  * NetExpr class is the root of a heirarchy that serves that purpose.
@@ -1734,10 +1758,15 @@ class NetForever : public NetProc {
 };
 
 /*
- * A funciton definition is elaborated just like a task, though by now
+ * A function definition is elaborated just like a task, though by now
  * it is certain that the first parameter (a phantom parameter) is the
  * output and all the remaining parameters are the inputs. This makes
- * for easy code generation in targets that support behavioral descriptions.
+ * for easy code generation in targets that support behavioral
+ * descriptions.
+ *
+ * The NetNet array that is passed in as a parameter is the set of
+ * signals that make up its parameter list. These are all internal to
+ * the scope of the function.
  */
 class NetFuncDef {
 
@@ -2891,6 +2920,9 @@ extern ostream& operator << (ostream&, NetNet::Type);
 
 /*
  * $Log: netlist.h,v $
+ * Revision 1.232  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.231  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
@@ -2901,255 +2933,5 @@ extern ostream& operator << (ostream&, NetNet::Type);
  *
  * Revision 1.229  2002/01/19 19:02:08  steve
  *  Pass back target errors processing conditionals.
- *
- * Revision 1.228  2001/12/31 00:08:14  steve
- *  Support $signed cast of expressions.
- *
- * Revision 1.227  2001/12/03 04:47:15  steve
- *  Parser and pform use hierarchical names as hname_t
- *  objects instead of encoded strings.
- *
- * Revision 1.226  2001/11/29 01:58:18  steve
- *  Handle part selects in l-values of DFF devices.
- *
- * Revision 1.225  2001/11/19 04:26:46  steve
- *  Unary reduction operators are all 1-bit results.
- *
- * Revision 1.224  2001/11/14 03:28:49  steve
- *  DLL target support for force and release.
- *
- * Revision 1.223  2001/11/09 03:43:26  steve
- *  Spelling errors.
- *
- * Revision 1.222  2001/11/08 05:15:51  steve
- *  Remove string paths from PExpr elaboration.
- *
- * Revision 1.221  2001/11/06 04:32:37  steve
- *  shift expressions can have definite widths.
- *
- * Revision 1.220  2001/10/31 05:24:52  steve
- *  ivl_target support for assign/deassign.
- *
- * Revision 1.219  2001/10/28 01:14:53  steve
- *  NetObj constructor finally requires a scope.
- *
- * Revision 1.218  2001/10/20 05:21:51  steve
- *  Scope/module names are char* instead of string.
- *
- * Revision 1.217  2001/10/19 21:53:24  steve
- *  Support multiple root modules (Philip Blundell)
- *
- * Revision 1.216  2001/10/16 02:19:27  steve
- *  Support IVL_LPM_DIVIDE for structural divide.
- *
- * Revision 1.215  2001/10/07 03:38:08  steve
- *  parameter names do not have defined size.
- *
- * Revision 1.214  2001/08/25 23:50:03  steve
- *  Change the NetAssign_ class to refer to the signal
- *  instead of link into the netlist. This is faster
- *  and uses less space. Make the NetAssignNB carry
- *  the delays instead of the NetAssign_ lval objects.
- *
- *  Change the vvp code generator to support multiple
- *  l-values, i.e. concatenations of part selects.
- *
- * Revision 1.213  2001/07/27 04:51:44  steve
- *  Handle part select expressions as variants of
- *  NetESignal/IVL_EX_SIGNAL objects, instead of
- *  creating new and useless temporary signals.
- *
- * Revision 1.212  2001/07/22 00:17:49  steve
- *  Support the NetESubSignal expressions in vvp.tgt.
- *
- * Revision 1.211  2001/07/04 22:59:25  steve
- *  handle left shifter in dll output.
- *
- * Revision 1.210  2001/07/01 00:27:34  steve
- *  Make NetFF constructor take const char* for the name.
- *
- * Revision 1.209  2001/06/16 23:45:05  steve
- *  Add support for structural multiply in t-dll.
- *  Add code generators and vvp support for both
- *  structural and behavioral multiply.
- *
- * Revision 1.208  2001/06/15 04:14:18  steve
- *  Generate vvp code for GT and GE comparisons.
- *
- * Revision 1.207  2001/06/07 02:12:43  steve
- *  Support structural addition.
- *
- * Revision 1.206  2001/05/08 23:59:33  steve
- *  Add ivl and vvp.tgt support for memories in
- *  expressions and l-values. (Stephan Boettcher)
- *
- * Revision 1.205  2001/04/29 20:19:10  steve
- *  Add pullup and pulldown devices.
- *
- * Revision 1.204  2001/04/24 02:23:58  steve
- *  Support for UDP devices in VVP (Stephen Boettcher)
- *
- * Revision 1.203  2001/04/22 23:09:46  steve
- *  More UDP consolidation from Stephan Boettcher.
- *
- * Revision 1.202  2001/04/06 02:28:02  steve
- *  Generate vvp code for functions with ports.
- *
- * Revision 1.201  2001/04/02 02:28:12  steve
- *  Generate code for task calls.
- *
- * Revision 1.200  2001/03/29 02:52:01  steve
- *  Add const probe method to NetEvent.
- *
- * Revision 1.199  2001/02/15 06:59:36  steve
- *  FreeBSD port has a maintainer now.
- *
- * Revision 1.198  2001/02/10 21:20:38  steve
- *  Binary operators with operands of indefinite width
- *  has itself an indefinite width.
- *
- * Revision 1.197  2001/02/10 20:29:39  steve
- *  In the context of range declarations, use elab_and_eval instead
- *  of the less robust eval_const methods.
- *
- * Revision 1.196  2001/02/09 05:44:23  steve
- *  support evaluation of constant < in expressions.
- *
- * Revision 1.195  2001/01/18 03:16:35  steve
- *  NetMux needs a scope. (PR#115)
- *
- * Revision 1.194  2001/01/16 02:44:18  steve
- *  Use the iosfwd header if available.
- *
- * Revision 1.193  2001/01/06 06:31:58  steve
- *  declaration initialization for time variables.
- *
- * Revision 1.192  2001/01/06 02:29:36  steve
- *  Support arrays of integers.
- *
- * Revision 1.191  2001/01/04 16:49:50  steve
- *  Evaluate constant === and !== expressions.
- *
- * Revision 1.190  2001/01/02 04:21:14  steve
- *  Support a bunch of unary operators in parameter expressions.
- *
- * Revision 1.189  2001/01/02 03:23:40  steve
- *  Evaluate constant &, | and unary ~.
- *
- * Revision 1.188  2000/12/16 19:03:30  steve
- *  Evaluate <= and ?: in parameter expressions (PR#81)
- *
- * Revision 1.187  2000/12/16 01:45:48  steve
- *  Detect recursive instantiations (PR#2)
- *
- * Revision 1.186  2000/12/11 00:31:43  steve
- *  Add support for signed reg variables,
- *  simulate in t-vvm signed comparisons.
- *
- * Revision 1.185  2000/12/05 06:29:33  steve
- *  Make signal attributes available to ivl_target API.
- *
- * Revision 1.184  2000/12/04 17:37:04  steve
- *  Add Attrib class for holding NetObj attributes.
- *
- * Revision 1.183  2000/12/02 05:08:04  steve
- *  Spelling error in comment.
- *
- * Revision 1.182  2000/11/29 05:24:00  steve
- *  synthesis for unary reduction ! and N operators.
- *
- * Revision 1.181  2000/11/29 02:09:53  steve
- *  Add support for || synthesis (PR#53)
- *
- * Revision 1.180  2000/11/20 00:58:40  steve
- *  Add support for supply nets (PR#17)
- *
- * Revision 1.179  2000/11/11 01:52:09  steve
- *  change set for support of nmos, pmos, rnmos, rpmos, notif0, and notif1
- *  change set to correct behavior of bufif0 and bufif1
- *  (Tim Leight)
- *
- *  Also includes fix for PR#27
- *
- * Revision 1.178  2000/11/11 00:03:36  steve
- *  Add support for the t-dll backend grabing flip-flops.
- *
- * Revision 1.177  2000/11/04 06:36:24  steve
- *  Apply sequential UDP rework from Stephan Boettcher  (PR#39)
- *
- * Revision 1.176  2000/10/31 17:49:02  steve
- *  Support time variables.
- *
- * Revision 1.175  2000/10/28 00:51:42  steve
- *  Add scope to threads in vvm, pass that scope
- *  to vpi sysTaskFunc objects, and add vpi calls
- *  to access that information.
- *
- *  $display displays scope in %m (PR#1)
- *
- * Revision 1.174  2000/10/18 20:04:39  steve
- *  Add ivl_lval_t and support for assignment l-values.
- *
- * Revision 1.173  2000/10/07 19:45:43  steve
- *  Put logic devices into scopes.
- *
- * Revision 1.172  2000/10/06 23:46:50  steve
- *  ivl_target updates, including more complete
- *  handling of ivl_nexus_t objects. Much reduced
- *  dependencies on pointers to netlist objects.
- *
- * Revision 1.171  2000/10/05 05:03:01  steve
- *  xor and constant devices.
- *
- * Revision 1.170  2000/10/04 16:30:39  steve
- *  Use char8 instead of string to store name.
- *
- * Revision 1.169  2000/09/29 04:43:09  steve
- *  Cnstant evaluation of NE.
- *
- * Revision 1.168  2000/09/26 05:05:58  steve
- *  Detect indefinite widths where definite widths are required.
- *
- * Revision 1.167  2000/09/26 01:35:42  steve
- *  Remove the obsolete NetEIdent class.
- *
- * Revision 1.166  2000/09/24 17:41:13  steve
- *  fix null pointer when elaborating undefined task.
- *
- * Revision 1.165  2000/09/24 15:44:44  steve
- *  Move some NetNet method out of the header file.
- *
- * Revision 1.164  2000/09/22 03:58:30  steve
- *  Access to the name of a system task call.
- *
- * Revision 1.163  2000/09/17 21:26:15  steve
- *  Add support for modulus (Eric Aardoom)
- *
- * Revision 1.162  2000/09/10 02:18:16  steve
- *  elaborate complex l-values
- *
- * Revision 1.161  2000/09/07 00:06:53  steve
- *  encapsulate access to the l-value expected width.
- *
- * Revision 1.160  2000/09/02 23:40:13  steve
- *  Pull NetAssign_ creation out of constructors.
- *
- * Revision 1.159  2000/09/02 20:54:20  steve
- *  Rearrange NetAssign to make NetAssign_ separate.
- *
- * Revision 1.158  2000/08/27 15:51:50  steve
- *  t-dll iterates signals, and passes them to the
- *  target module.
- *
- *  Some of NetObj should return char*, not string.
- *
- * Revision 1.157  2000/08/26 00:54:03  steve
- *  Get at gate information for ivl_target interface.
- *
- * Revision 1.156  2000/08/14 04:39:57  steve
- *  add th t-dll functions for net_const, net_bufz and processes.
- *
- * Revision 1.155  2000/08/09 03:43:45  steve
- *  Move all file manipulation out of target class.
  */
 #endif
diff --git a/t-dll-api.cc b/t-dll-api.cc
index d8a11bc76..39eb1b0a8 100644
--- a/t-dll-api.cc
+++ b/t-dll-api.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: t-dll-api.cc,v 1.75 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: t-dll-api.cc,v 1.76 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -674,6 +674,10 @@ extern "C" ivl_nexus_t ivl_lpm_q(ivl_lpm_t net, unsigned idx)
 	    assert(idx < net->u_.shift.width);
 	    return net->u_.shift.q[idx];
 
+	  case IVL_LPM_UFUNC:
+	    assert(idx < net->u_.ufunc.port_wid[0]);
+	    return net->u_.ufunc.pins[idx];
+
 	  default:
 	    assert(0);
 	    return 0;
@@ -768,6 +772,8 @@ extern "C" unsigned ivl_lpm_width(ivl_lpm_t net)
 	  case IVL_LPM_SHIFTL:
 	  case IVL_LPM_SHIFTR:
 	    return net->u_.shift.width;
+	  case IVL_LPM_UFUNC:
+	    return net->u_.ufunc.port_wid[0];
 	  default:
 	    assert(0);
 	    return 0;
@@ -1452,6 +1458,9 @@ extern "C" ivl_statement_t ivl_stmt_sub_stmt(ivl_statement_t net)
 
 /*
  * $Log: t-dll-api.cc,v $
+ * Revision 1.76  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.75  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
diff --git a/t-dll.cc b/t-dll.cc
index 688236052..0f6d6202c 100644
--- a/t-dll.cc
+++ b/t-dll.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2002 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: t-dll.cc,v 1.79 2002/01/23 04:54:37 steve Exp $"
+#ident "$Id: t-dll.cc,v 1.80 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -788,6 +788,59 @@ bool dll_target::net_force(const NetForce*net)
       return true;
 }
 
+/*
+ * An IVL_LPM_UFUNC represents a node in a combinational expression
+ * that calls a user defined function. I create an LPM object that has
+ * the right connections, and refers to the ivl_scope_t of the
+ * definition.
+ */
+bool dll_target::net_function(const NetUserFunc*net)
+{
+      struct ivl_lpm_s*obj = new struct ivl_lpm_s;
+      obj->type = IVL_LPM_UFUNC;
+      obj->name  = strdup(net->name());
+      obj->scope = find_scope(des_, net->scope());
+      assert(obj->scope);
+
+	/* Get the definition of the function and save it. */
+      const NetScope*def = net->def();
+      assert(def);
+
+      obj->u_.ufunc.def = lookup_scope_(def);
+
+	/* Save information about the ports in the ivl_lpm_s
+	   structure. Note that port 0 is the return value. */
+      obj->u_.ufunc.ports = net->port_count();
+      obj->u_.ufunc.port_wid = new unsigned short[net->port_count()];
+      for (unsigned idx = 0 ;  idx < obj->u_.ufunc.ports ;  idx += 1)
+	    obj->u_.ufunc.port_wid[idx] = net->port_width(idx);
+
+	/* Now collect all the pins and connect them to the nexa of
+	   the net. The output pins have strong drive, and the
+	   remaining input pins are HiZ. */
+
+      unsigned pin_count = net->pin_count();
+      obj->u_.ufunc.pins = new ivl_nexus_t[pin_count];
+
+      for (unsigned idx = 0 ;  idx < pin_count ;  idx += 1) {
+	    const Nexus*nex = net->pin(idx).nexus();
+	    assert(nex->t_cookie());
+	    ivl_nexus_t nn = (ivl_nexus_t)nex->t_cookie();
+	    assert(nn);
+
+	    obj->u_.ufunc.pins[idx] = nn;
+	    ivl_drive_t drive = idx < obj->u_.ufunc.port_wid[0]
+		  ? IVL_DR_STRONG
+		  : IVL_DR_HiZ;
+	    nexus_lpm_add(obj->u_.ufunc.pins[idx], obj, idx, drive, drive);
+      }
+
+	/* All done. Add this LPM to the scope. */
+      scope_add_lpm(obj->scope, obj);
+
+      return true;
+}
+
 void dll_target::udp(const NetUDP*net)
 {
       struct ivl_net_logic_s *obj = new struct ivl_net_logic_s;
@@ -1876,6 +1929,9 @@ extern const struct target tgt_dll = { "dll", &dll_target_obj };
 
 /*
  * $Log: t-dll.cc,v $
+ * Revision 1.80  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.79  2002/01/23 04:54:37  steve
  *  Load modules with RTLD_LAZY
  *
@@ -1906,114 +1962,5 @@ extern const struct target tgt_dll = { "dll", &dll_target_obj };
  *
  * Revision 1.70  2001/11/14 03:28:49  steve
  *  DLL target support for force and release.
- *
- * Revision 1.69  2001/10/30 02:52:07  steve
- *  Stubs for assign/deassign for t-dll.
- *
- * Revision 1.68  2001/10/22 02:05:21  steve
- *  Handle activating tasks in another root.
- *
- * Revision 1.67  2001/10/19 21:53:24  steve
- *  Support multiple root modules (Philip Blundell)
- *
- * Revision 1.66  2001/10/16 02:19:27  steve
- *  Support IVL_LPM_DIVIDE for structural divide.
- *
- * Revision 1.65  2001/10/11 00:13:19  steve
- *  Initialize attributes for bufz devices.
- *
- * Revision 1.64  2001/09/16 22:19:42  steve
- *  Support attributes to logic gates.
- *
- * Revision 1.63  2001/09/15 18:27:04  steve
- *  Make configure detect malloc.h
- *
- * Revision 1.62  2001/09/09 16:49:04  steve
- *  Connect right ANEB pin when doing NE comparator.
- *
- * Revision 1.61  2001/09/08 01:23:21  steve
- *  No code for unlinked constants.
- *
- * Revision 1.60  2001/09/01 01:57:31  steve
- *  Make constants available through the design root
- *
- * Revision 1.59  2001/08/31 22:58:39  steve
- *  Support DFF CE inputs.
- *
- * Revision 1.58  2001/08/28 04:07:41  steve
- *  Add some ivl_target convenience functions.
- *
- * Revision 1.57  2001/08/10 00:40:45  steve
- *  tgt-vvp generates code that skips nets as inputs.
- *
- * Revision 1.56  2001/07/25 03:10:50  steve
- *  Create a config.h.in file to hold all the config
- *  junk, and support gcc 3.0. (Stephan Boettcher)
- *
- * Revision 1.55  2001/07/22 00:17:49  steve
- *  Support the NetESubSignal expressions in vvp.tgt.
- *
- * Revision 1.54  2001/07/07 03:01:37  steve
- *  Detect and make available to t-dll the right shift.
- *
- * Revision 1.53  2001/07/04 22:59:25  steve
- *  handle left shifter in dll output.
- *
- * Revision 1.52  2001/06/30 23:03:16  steve
- *  support fast programming by only writing the bits
- *  that are listed in the input file.
- *
- * Revision 1.51  2001/06/19 03:01:10  steve
- *  Add structural EEQ gates (Stephan Boettcher)
- *
- * Revision 1.50  2001/06/18 03:25:20  steve
- *  RAM_DQ pins are inputs, so connect HiZ to the nexus.
- *
- * Revision 1.49  2001/06/16 23:45:05  steve
- *  Add support for structural multiply in t-dll.
- *  Add code generators and vvp support for both
- *  structural and behavioral multiply.
- *
- * Revision 1.48  2001/06/16 02:41:42  steve
- *  Generate code to support memory access in continuous
- *  assignment statements. (Stephan Boettcher)
- *
- * Revision 1.47  2001/06/15 05:01:09  steve
- *  support LE and LT comparators.
- *
- * Revision 1.46  2001/06/15 04:14:19  steve
- *  Generate vvp code for GT and GE comparisons.
- *
- * Revision 1.45  2001/06/07 04:20:10  steve
- *  Account for carry out on add devices.
- *
- * Revision 1.44  2001/06/07 03:09:37  steve
- *  support subtraction in tgt-vvp.
- *
- * Revision 1.43  2001/06/07 02:12:43  steve
- *  Support structural addition.
- *
- * Revision 1.42  2001/05/20 15:09:39  steve
- *  Mingw32 support (Venkat Iyer)
- *
- * Revision 1.41  2001/05/12 03:18:45  steve
- *  Make sure LPM devices have drives on outputs.
- *
- * Revision 1.40  2001/05/08 23:59:33  steve
- *  Add ivl and vvp.tgt support for memories in
- *  expressions and l-values. (Stephan Boettcher)
- *
- * Revision 1.39  2001/05/03 01:52:45  steve
- *  dll build of many probes forgot to index the probe.
- *
- * Revision 1.38  2001/04/29 23:17:38  steve
- *  Carry drive strengths in the ivl_nexus_ptr_t, and
- *  handle constant devices in targets.'
- *
- * Revision 1.37  2001/04/29 20:19:10  steve
- *  Add pullup and pulldown devices.
- *
- * Revision 1.36  2001/04/26 05:12:02  steve
- *  Implement simple MUXZ for ?: operators.
  */
 
diff --git a/t-dll.h b/t-dll.h
index fa8989aa3..a2d6161a0 100644
--- a/t-dll.h
+++ b/t-dll.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: t-dll.h,v 1.75 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: t-dll.h,v 1.76 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include  "target.h"
@@ -82,6 +82,7 @@ struct dll_target  : public target_t, public expr_scan_t {
       void net_assign(const NetAssign_*);
       bool net_cassign(const NetCAssign*);
       bool net_force(const NetForce*);
+      bool net_function(const NetUserFunc*);
       bool net_const(const NetConst*);
       void net_probe(const NetEvProbe*);
 
@@ -301,6 +302,13 @@ struct ivl_lpm_s {
 		  unsigned short width;
 		  ivl_nexus_t*q, *a, *b;
 	    } arith;
+
+	    struct ivl_lpm_ufunc_s {
+		  ivl_scope_t def;
+		  unsigned short ports;
+		  unsigned short*port_wid;
+		  ivl_nexus_t*pins;
+	    } ufunc;
       } u_;
 };
 
@@ -591,6 +599,9 @@ struct ivl_statement_s {
 
 /*
  * $Log: t-dll.h,v $
+ * Revision 1.76  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.75  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
@@ -616,86 +627,5 @@ struct ivl_statement_s {
  *
  * Revision 1.68  2001/10/31 05:24:52  steve
  *  ivl_target support for assign/deassign.
- *
- * Revision 1.67  2001/10/30 02:52:07  steve
- *  Stubs for assign/deassign for t-dll.
- *
- * Revision 1.66  2001/10/19 21:53:24  steve
- *  Support multiple root modules (Philip Blundell)
- *
- * Revision 1.65  2001/10/16 02:19:27  steve
- *  Support IVL_LPM_DIVIDE for structural divide.
- *
- * Revision 1.64  2001/09/16 22:19:42  steve
- *  Support attributes to logic gates.
- *
- * Revision 1.63  2001/09/01 01:57:31  steve
- *  Make constants available through the design root
- *
- * Revision 1.62  2001/08/31 22:58:40  steve
- *  Support DFF CE inputs.
- *
- * Revision 1.61  2001/08/28 04:07:41  steve
- *  Add some ivl_target convenience functions.
- *
- * Revision 1.60  2001/08/25 23:50:03  steve
- *  Change the NetAssign_ class to refer to the signal
- *  instead of link into the netlist. This is faster
- *  and uses less space. Make the NetAssignNB carry
- *  the delays instead of the NetAssign_ lval objects.
- *
- *  Change the vvp code generator to support multiple
- *  l-values, i.e. concatenations of part selects.
- *
- * Revision 1.59  2001/08/10 00:40:45  steve
- *  tgt-vvp generates code that skips nets as inputs.
- *
- * Revision 1.58  2001/07/27 04:51:44  steve
- *  Handle part select expressions as variants of
- *  NetESignal/IVL_EX_SIGNAL objects, instead of
- *  creating new and useless temporary signals.
- *
- * Revision 1.57  2001/07/27 02:41:56  steve
- *  Fix binding of dangling function ports. do not elide them.
- *
- * Revision 1.56  2001/07/22 00:17:50  steve
- *  Support the NetESubSignal expressions in vvp.tgt.
- *
- * Revision 1.55  2001/07/19 04:55:06  steve
- *  Support calculated delays in vvp.tgt.
- *
- * Revision 1.54  2001/07/07 20:20:10  steve
- *  Pass parameters to system functions.
- *
- * Revision 1.53  2001/07/04 22:59:25  steve
- *  handle left shifter in dll output.
- *
- * Revision 1.52  2001/06/30 23:03:16  steve
- *  support fast programming by only writing the bits
- *  that are listed in the input file.
- *
- * Revision 1.51  2001/06/30 21:07:26  steve
- *  Support non-const right shift (unsigned).
- *
- * Revision 1.50  2001/06/19 03:01:10  steve
- *  Add structural EEQ gates (Stephan Boettcher)
- *
- * Revision 1.49  2001/06/16 23:45:05  steve
- *  Add support for structural multiply in t-dll.
- *  Add code generators and vvp support for both
- *  structural and behavioral multiply.
- *
- * Revision 1.48  2001/06/16 02:41:42  steve
- *  Generate code to support memory access in continuous
- *  assignment statements. (Stephan Boettcher)
- *
- * Revision 1.47  2001/06/15 04:14:19  steve
- *  Generate vvp code for GT and GE comparisons.
- *
- * Revision 1.46  2001/06/07 02:12:43  steve
- *  Support structural addition.
- *
- * Revision 1.45  2001/05/20 15:09:39  steve
- *  Mingw32 support (Venkat Iyer)
  */
 #endif
diff --git a/target.cc b/target.cc
index 2c5809763..2e2ad85c6 100644
--- a/target.cc
+++ b/target.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998-2000 Stephen Williams <steve@icarus.com>
+ * Copyright (c) 1998-2002 Stephen Williams <steve@icarus.com>
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: target.cc,v 1.59 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: target.cc,v 1.60 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -158,6 +158,13 @@ bool target_t::net_force(const NetForce*dev)
       return false;
 }
 
+bool target_t::net_function(const NetUserFunc*net)
+{
+      cerr << "target (" << typeid(*this).name() <<  "): "
+	    "Unhandled NetUserFunc node." << endl;
+      return false;
+}
+
 void target_t::net_probe(const NetEvProbe*net)
 {
       cerr << "target (" << typeid(*this).name() << "): "
@@ -390,6 +397,9 @@ void expr_scan_t::expr_binary(const NetEBinary*ex)
 
 /*
  * $Log: target.cc,v $
+ * Revision 1.60  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.59  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
diff --git a/target.h b/target.h
index 8ef9cf674..30e8ca4e5 100644
--- a/target.h
+++ b/target.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: target.h,v 1.56 2002/01/28 00:52:41 steve Exp $"
+#ident "$Id: target.h,v 1.57 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include  "netlist.h"
@@ -91,6 +91,7 @@ struct target_t {
       virtual bool net_cassign(const NetCAssign*);
       virtual bool net_const(const NetConst*);
       virtual bool net_force(const NetForce*);
+      virtual bool net_function(const NetUserFunc*);
       virtual void net_probe(const NetEvProbe*);
 
 	/* Output a process (called for each process). It is up to the
@@ -163,6 +164,9 @@ extern const struct target *target_table[];
 
 /*
  * $Log: target.h,v $
+ * Revision 1.57  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.56  2002/01/28 00:52:41  steve
  *  Add support for bit select of parameters.
  *  This leads to a NetESelect node and the
diff --git a/tgt-vvp/vvp_scope.c b/tgt-vvp/vvp_scope.c
index d7dec5ba6..8cf60ef75 100644
--- a/tgt-vvp/vvp_scope.c
+++ b/tgt-vvp/vvp_scope.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT)
-#ident "$Id: vvp_scope.c,v 1.64 2002/01/12 17:49:41 steve Exp $"
+#ident "$Id: vvp_scope.c,v 1.65 2002/03/09 02:10:22 steve Exp $"
 #endif
 
 # include  "vvp_priv.h"
@@ -319,6 +319,7 @@ static const char* draw_net_input_drive(ivl_nexus_t nex, ivl_nexus_ptr_t nptr)
 	  case IVL_LPM_MULT:
 	  case IVL_LPM_DIVIDE:
 	  case IVL_LPM_MOD:
+	  case IVL_LPM_UFUNC:
 	    for (idx = 0 ;  idx < ivl_lpm_width(lpm) ;  idx += 1)
 		  if (ivl_lpm_q(lpm, idx) == nex) {
 			sprintf(result, "L_%s[%u]",
@@ -1278,6 +1279,14 @@ static void draw_lpm_shiftl(ivl_lpm_t net)
       fprintf(vvp_out, ";\n");
 }
 
+static void draw_lpm_ufunc(ivl_lpm_t net)
+{
+      fprintf(stderr, "tgt-vvp: ivl_ufunc not yet supported.\n");
+      fprintf(vvp_out, "L_%s .func %u %u;\n",
+	      vvp_mangle_id(ivl_lpm_name(net)),
+	      ivl_lpm_width(net), 0);
+}
+
 static void draw_lpm_in_scope(ivl_lpm_t net)
 {
       switch (ivl_lpm_type(net)) {
@@ -1313,6 +1322,10 @@ static void draw_lpm_in_scope(ivl_lpm_t net)
 	    draw_lpm_shiftl(net);
 	    return;
 
+	  case IVL_LPM_UFUNC:
+	    draw_lpm_ufunc(net);
+	    return;
+
 	  default:
 	    fprintf(stderr, "XXXX LPM not supported: %s\n",
 		    ivl_lpm_name(net));
@@ -1410,6 +1423,9 @@ int draw_scope(ivl_scope_t net, ivl_scope_t parent)
 
 /*
  * $Log: vvp_scope.c,v $
+ * Revision 1.65  2002/03/09 02:10:22  steve
+ *  Add the NetUserFunc netlist node.
+ *
  * Revision 1.64  2002/01/12 17:49:41  steve
  *  Handle constants with drive strength z
  *