diff --git a/design_dump.cc b/design_dump.cc
index c616e01a6..a82582220 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
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: design_dump.cc,v 1.149.2.3 2006/03/12 07:34:16 steve Exp $"
+#ident "$Id: design_dump.cc,v 1.149.2.4 2006/03/26 23:09:21 steve Exp $"
 #endif
 
 # include "config.h"
@@ -224,6 +224,14 @@ void NetDecode::dump_node(ostream&o, unsigned ind) const
       dump_obj_attr(o, ind+4);
 }
 
+void NetDemux::dump_node(ostream&o, unsigned ind) const
+{
+      o << setw(ind) << "" << "LPM_DEMUX (NetDemux): " << name()
+	<< " word width=" << width() << ", address width=" << awidth() << endl;
+      dump_node_pins(o, ind+4);
+      dump_obj_attr(o, ind+4);
+}
+
 void NetDivide::dump_node(ostream&o, unsigned ind) const
 {
       o << setw(ind) << "" << "NET_DIVIDE (NetDivide): " << name() << endl;
@@ -1109,6 +1117,9 @@ void Design::dump(ostream&o) const
 
 /*
  * $Log: design_dump.cc,v $
+ * Revision 1.149.2.4  2006/03/26 23:09:21  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.149.2.3  2006/03/12 07:34:16  steve
  *  Fix the memsynth1 case.
  *
diff --git a/emit.cc b/emit.cc
index 2df371447..841eda956 100644
--- a/emit.cc
+++ b/emit.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: emit.cc,v 1.77.2.1 2006/02/19 00:11:31 steve Exp $"
+#ident "$Id: emit.cc,v 1.77.2.2 2006/03/26 23:09:21 steve Exp $"
 #endif
 
 # include "config.h"
@@ -91,6 +91,11 @@ bool NetDecode::emit_node(struct target_t*tgt) const
       return tgt->lpm_decode(this);
 }
 
+bool NetDemux::emit_node(struct target_t*tgt) const
+{
+      return tgt->lpm_demux(this);
+}
+
 bool NetDivide::emit_node(struct target_t*tgt) const
 {
       tgt->lpm_divide(this);
@@ -516,6 +521,9 @@ bool emit(const Design*des, const char*type)
 
 /*
  * $Log: emit.cc,v $
+ * Revision 1.77.2.2  2006/03/26 23:09:21  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.77.2.1  2006/02/19 00:11:31  steve
  *  Handle synthesis of FF vectors with l-value decoder.
  *
diff --git a/ivl_target.h b/ivl_target.h
index 975bf13ee..8c155b62f 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
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: ivl_target.h,v 1.126.2.3 2006/03/12 07:34:16 steve Exp $"
+#ident "$Id: ivl_target.h,v 1.126.2.4 2006/03/26 23:09:22 steve Exp $"
 #endif
 
 #ifdef __cplusplus
@@ -227,6 +227,7 @@ typedef enum ivl_lpm_type_e {
       IVL_LPM_CMP_GT =  2,
       IVL_LPM_CMP_NE = 11,
       IVL_LPM_DECODE = 15,
+      IVL_LPM_DEMUX  = 16,
       IVL_LPM_DIVIDE = 12,
       IVL_LPM_FF     =  3,
       IVL_LPM_MOD    = 13,
@@ -705,6 +706,17 @@ extern const char* ivl_udp_name(ivl_udp_t net);
  * "q" port has as many bits as the width. The ivl_lpm_data2 function
  * gets the nexa of the input, with the sdx the word address and the
  * idx the bit within the word.
+ *
+ * - IVL_LPM_DEMUX
+ * This device is a form of bit replacement. The device has a data
+ * width (ivl_lpm_width) and an address width. The Data outputs are
+ * ivl_lpm_q and have the data width. The ivl_lpm_data functions are
+ * inputs to the device. Normally, the device passes the data inputs
+ * through to the Q output.
+ *
+ * The ivl_lpm_select inputs address a bit of the device. The
+ * addressed bit is substituted by the replacement bit. This
+ * replacement bit comes from the ivl_lpm_datab(net,0) nexus.
  */
 
 extern const char*    ivl_lpm_name(ivl_lpm_t net); /* (Obsolete) */
@@ -732,20 +744,21 @@ extern ivl_lpm_t   ivl_lpm_decode(ivl_lpm_t net);
 extern ivl_scope_t  ivl_lpm_define(ivl_lpm_t net);
   /* IVL_LPM_FF IVL_LPM_RAM */
 extern ivl_nexus_t ivl_lpm_enable(ivl_lpm_t net);
-  /* IVL_LPM_ADD IVL_LPM_FF IVL_LPM_MULT IVL_LPM_RAM IVL_LPM_SUB */
+  /* IVL_LPM_ADD IVL_LPM_DEMUX IVL_LPM_FF IVL_LPM_MULT */
+  /*  IVL_LPM_RAM IVL_LPM_SUB */
 extern ivl_nexus_t ivl_lpm_data(ivl_lpm_t net, unsigned idx);
-  /* IVL_LPM_ADD IVL_LPM_MULT IVL_LPM_SUB */
+  /* IVL_LPM_ADD IVL_LPM_DEMUX IVL_LPM_MULT IVL_LPM_SUB */
   /* IVL_LPM_MUX IVL_LPM_UFUNC */
 extern ivl_nexus_t ivl_lpm_datab(ivl_lpm_t net, unsigned idx);
 extern ivl_nexus_t ivl_lpm_data2(ivl_lpm_t net, unsigned sdx, unsigned idx);
   /* IVL_LPM_UFUNC */
 extern unsigned ivl_lpm_data2_width(ivl_lpm_t net, unsigned sdx);
-  /* IVL_LPM_ADD IVL_LPM_FF IVL_LPM_MULT IVL_LPM_RAM IVL_LPM_SUB
+  /* IVL_LPM_ADD IVL_LPM_DEMUX 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_DECODE IVL_LPM_RAM */
+  /* IVL_LPM_MUX IVL_LPM_DECODE IVL_LPM_DEMUX IVL_LPM_RAM */
 extern unsigned ivl_lpm_selects(ivl_lpm_t net);
-  /* IVL_LPM_MUX IVL_LPM_DECODE IVL_LPM_RAM */
+  /* IVL_LPM_MUX IVL_LPM_DECODE IVL_LPM_DEMUX IVL_LPM_RAM */
 extern ivl_nexus_t ivl_lpm_select(ivl_lpm_t net, unsigned idx);
   /* IVL_LPM_MUX, IVL_LPM_RAM */
 extern unsigned ivl_lpm_size(ivl_lpm_t net);
@@ -1288,6 +1301,9 @@ _END_DECL
 
 /*
  * $Log: ivl_target.h,v $
+ * Revision 1.126.2.4  2006/03/26 23:09:22  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.126.2.3  2006/03/12 07:34:16  steve
  *  Fix the memsynth1 case.
  *
diff --git a/netlist.cc b/netlist.cc
index 65b1d212d..70fff8faf 100644
--- a/netlist.cc
+++ b/netlist.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: netlist.cc,v 1.226.2.4 2006/03/16 05:40:18 steve Exp $"
+#ident "$Id: netlist.cc,v 1.226.2.5 2006/03/26 23:09:22 steve Exp $"
 #endif
 
 # include "config.h"
@@ -721,6 +721,89 @@ unsigned NetDecode::awidth() const
       return pin_count();
 }
 
+NetDemux::NetDemux(NetScope*s, perm_string name,
+		   unsigned word_width, unsigned address_width)
+: NetNode(s, name, word_width*2+address_width+1)
+{
+      width_ = word_width;
+      awidth_ = address_width;
+
+      for (unsigned idx = 0 ;  idx < width_ ;  idx += 1) {
+	    pin_Q(idx).set_dir(Link::OUTPUT);
+	    pin_Q(idx).set_name(perm_string::literal("Q"), idx);
+      }
+      for (unsigned idx = 0 ;  idx < width_ ;  idx += 1) {
+	    pin_Data(idx).set_dir(Link::INPUT);
+	    pin_Data(idx).set_name(perm_string::literal("Data"), idx);
+      }
+      for (unsigned idx = 0 ;  idx < awidth_ ;  idx += 1) {
+	    pin_Address(idx).set_dir(Link::INPUT);
+	    pin_Address(idx).set_name(perm_string::literal("Address"), idx);
+      }
+      pin_WriteData().set_dir(Link::INPUT);
+      pin_WriteData().set_name(perm_string::literal("Writedata"), 0);
+}
+
+NetDemux::~NetDemux()
+{
+}
+
+unsigned NetDemux::width() const
+{
+      return width_;
+}
+
+unsigned NetDemux::awidth() const
+{
+      return awidth_;
+}
+
+Link& NetDemux::pin_Q(unsigned idx)
+{
+      assert(idx < width_);
+      return pin(idx);
+}
+
+const Link& NetDemux::pin_Q(unsigned idx) const
+{
+      assert(idx < width_);
+      return pin(idx);
+}
+
+Link& NetDemux::pin_Data(unsigned idx)
+{
+      assert(idx < width_);
+      return pin(width_+idx);
+}
+
+const Link& NetDemux::pin_Data(unsigned idx) const
+{
+      assert(idx < width_);
+      return pin(width_+idx);
+}
+
+Link& NetDemux::pin_Address(unsigned idx)
+{
+      assert(idx < awidth_);
+      return pin(width_+width_+idx);
+}
+
+const Link& NetDemux::pin_Address(unsigned idx) const
+{
+      assert(idx < awidth_);
+      return pin(width_+width_+idx);
+}
+
+Link& NetDemux::pin_WriteData()
+{
+      return pin(width_+width_+awidth_);
+}
+
+const Link& NetDemux::pin_WriteData() const
+{
+      return pin(width_+width_+awidth_);
+}
+
 NetDecode* NetFF::get_demux()
 {
       return demux_;
@@ -2388,6 +2471,9 @@ const NetProc*NetTaskDef::proc() const
 
 /*
  * $Log: netlist.cc,v $
+ * Revision 1.226.2.5  2006/03/26 23:09:22  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.226.2.4  2006/03/16 05:40:18  steve
  *  Fix crash when memory exploding doesnot work
  *
diff --git a/netlist.h b/netlist.h
index a37d6c207..c595bd8fe 100644
--- a/netlist.h
+++ b/netlist.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: netlist.h,v 1.321.2.13 2006/03/18 18:43:21 steve Exp $"
+#ident "$Id: netlist.h,v 1.321.2.14 2006/03/26 23:09:23 steve Exp $"
 #endif
 
 /*
@@ -635,6 +635,46 @@ class NetDecode  : public NetNode {
       void make_pins_(unsigned awid);
 };
 
+/*
+ * The NetDemux is similar to the NetDecode, except that it is
+ * combinational. The inputs are an address, Data, and WriteData.
+ * The Q output is the same as the Data input, except for the bit that
+ * is addressed by the address input, which gets WriteData instead.
+ */
+class NetDemux  : public NetNode {
+
+    public:
+      NetDemux(NetScope*s, perm_string name,
+	       unsigned word_width, unsigned address_width);
+      ~NetDemux();
+
+	// This is the width of the word. The width of the NetFF mem
+	// is an even multiple of this.
+      unsigned width() const;
+	// This is the width of the address. The address value for the
+	// base of a word is the address * width().
+      unsigned awidth() const;
+
+      Link& pin_Address(unsigned idx);
+      Link& pin_Data(unsigned idx);
+      Link& pin_Q(unsigned idx);
+      Link& pin_WriteData();
+
+      const Link& pin_Address(unsigned idx) const;
+      const Link& pin_Data(unsigned idx) const;
+      const Link& pin_Q(unsigned idx) const;
+      const Link& pin_WriteData() const;
+
+      virtual void dump_node(ostream&, unsigned ind) const;
+      virtual bool emit_node(struct target_t*) const;
+
+    private:
+      unsigned width_, awidth_;
+
+    private:
+      void make_pins_(unsigned wid, unsigned awid);
+};
+
 /*
  * This class represents a theoretical (though not necessarily
  * practical) integer divider gate. This is not to represent any real
@@ -1425,9 +1465,13 @@ class NetProc : public virtual LineInfo {
 	// sync_flag is used to tell the async synthesizer that the
 	// output nex_map is ultimately connected to a DFF Q
 	// output. This can affect how cycles are handled.
-      virtual bool synth_async(Design*des, NetScope*scope, bool sync_flag,
+
+      bool synth_async_noaccum(Design*des, NetScope*scope, bool sync_flag,
+			       struct sync_accounting_cell*nex_ff,
 			       NetNet*nex_map, NetNet*nex_out);
+
       virtual bool synth_async(Design*des, NetScope*scope, bool sync_flag,
+			       struct sync_accounting_cell*nex_ff,
 			       NetNet*nex_map, NetNet*nex_out,
 			       NetNet*accum_in);
 
@@ -1571,8 +1615,7 @@ class NetAssignBase : public NetProc {
       unsigned lwidth() const;
 
       bool synth_async(Design*des, NetScope*scope, bool sync_flag,
-		       NetNet*nex_map, NetNet*nex_out);
-      bool synth_async(Design*des, NetScope*scope, bool sync_flag,
+		       struct sync_accounting_cell*nex_ff,
 		       NetNet*nex_map, NetNet*nex_out,
 		       NetNet*accum_in);
       bool synth_sync(Design*des, NetScope*scope,
@@ -1645,7 +1688,8 @@ class NetBlock  : public NetProc {
 
 	// synthesize as asynchronous logic, and return true.
       bool synth_async(Design*des, NetScope*scope, bool sync_flag,
-		       NetNet*nex_map, NetNet*nex_out);
+		       struct sync_accounting_cell*nex_ff,
+		       NetNet*nex_map, NetNet*nex_out, NetNet*accum_in);
 
       bool synth_sync(Design*des, NetScope*scope,
 		      struct sync_accounting_cell*nex_ff,
@@ -1701,8 +1745,7 @@ class NetCase  : public NetProc {
       virtual void nex_output(NexusSet&out);
 
       bool synth_async(Design*des, NetScope*scope, bool sync_flag,
-		       NetNet*nex_map, NetNet*nex_out);
-      bool synth_async(Design*des, NetScope*scope, bool sync_flag,
+		       struct sync_accounting_cell*nex_ff,
 		       NetNet*nex_map, NetNet*nex_out, NetNet*accum_in);
 
       virtual bool emit_proc(struct target_t*) const;
@@ -1710,6 +1753,7 @@ class NetCase  : public NetProc {
 
     private:
       bool synth_async_1hot_(Design*des, NetScope*scope, bool sync_flag,
+			     struct sync_accounting_cell*nex_ff,
 			     NetNet*nex_map, NetNet*nex_out, NetNet*accum_in,
 			     NetNet*esig, unsigned hot_items);
     private:
@@ -1789,8 +1833,7 @@ class NetCondit  : public NetProc {
 
       bool is_asynchronous();
       bool synth_async(Design*des, NetScope*scope, bool sync_flag,
-		       NetNet*nex_map, NetNet*nex_out);
-      bool synth_async(Design*des, NetScope*scope, bool sync_flag,
+		       struct sync_accounting_cell*nex_ff,
 		       NetNet*nex_map, NetNet*nex_out, NetNet*accum);
 
       bool synth_sync(Design*des, NetScope*scope,
@@ -2017,7 +2060,9 @@ class NetEvWait  : public NetProc {
       virtual void nex_output(NexusSet&out);
 
       virtual bool synth_async(Design*des, NetScope*scope, bool sync_flag,
-			       NetNet*nex_map, NetNet*nex_out);
+			       struct sync_accounting_cell*nex_ff,
+			       NetNet*nex_map, NetNet*nex_out,
+			       NetNet*accum_in);
 
       virtual bool synth_sync(Design*des, NetScope*scope,
 			      struct sync_accounting_cell*nex_ff,
@@ -2416,7 +2461,8 @@ class NetWhile  : public NetProc {
       virtual void dump(ostream&, unsigned ind) const;
 
       bool synth_async(Design*des, NetScope*scope, bool sync_flag,
-		       NetNet*nex_map, NetNet*nex_out);
+		       struct sync_accounting_cell*nex_ff,
+		       NetNet*nex_map, NetNet*nex_out, NetNet*accum_in);
 
     private:
       NetExpr* cond_;
@@ -3466,6 +3512,9 @@ extern ostream& operator << (ostream&, NetNet::Type);
 
 /*
  * $Log: netlist.h,v $
+ * Revision 1.321.2.14  2006/03/26 23:09:23  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.321.2.13  2006/03/18 18:43:21  steve
  *  Better error messages when synthesis fails.
  *
diff --git a/synth2.cc b/synth2.cc
index ca581a02a..23082eee9 100644
--- a/synth2.cc
+++ b/synth2.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: synth2.cc,v 1.39.2.25 2006/03/18 18:43:22 steve Exp $"
+#ident "$Id: synth2.cc,v 1.39.2.26 2006/03/26 23:09:24 steve Exp $"
 #endif
 
 # include "config.h"
@@ -41,17 +41,27 @@ static int debug_synth2=0;
 #define DEBUG_SYNTH2_EXIT(class,val)
 #endif
 
-bool NetProc::synth_async(Design*des, NetScope*scope, bool sync_flag,
-			  NetNet*nex_map, NetNet*nex_out)
+bool NetProc::synth_async_noaccum(Design*des, NetScope*scope, bool sync_flag,
+				  struct sync_accounting_cell*nex_ff,
+				  NetNet*nex_map, NetNet*nex_out)
 {
-      return false;
+	/* Make an unconnected stub for the accum_in net. */
+      const perm_string tmp = perm_string::literal("tmp");
+      NetNet*stub = new NetNet(scope, tmp, NetNet::WIRE, nex_out->pin_count());
+
+      bool flag = synth_async(des, scope, sync_flag, nex_ff,
+			      nex_map, nex_out, stub);
+
+      delete stub;
+      return flag;
 }
 
 bool NetProc::synth_async(Design*des, NetScope*scope, bool sync_flag,
+			  struct sync_accounting_cell*nex_ff,
 			  NetNet*nex_map, NetNet*nex_out,
 			  NetNet*accum_in)
 {
-      return synth_async(des, scope, sync_flag, nex_map, nex_out);
+      return false;
 }
 
 bool NetProc::synth_sync(Design*des, NetScope*scope,
@@ -59,8 +69,7 @@ bool NetProc::synth_sync(Design*des, NetScope*scope,
 			 NetNet*nex_map, NetNet*nex_out,
 			 const svector<NetEvProbe*>&events)
 {
-	/* Synthesize the input to the DFF. */
-      return synth_async(des, scope, true, nex_map, nex_out);
+      return synth_async_noaccum(des, scope, true, nex_ff, nex_map, nex_out);
 }
 
 static unsigned find_nexus_in_set(const NetNet*nset, const Nexus*nex)
@@ -85,16 +94,7 @@ static unsigned find_nexus_in_set(const NetNet*nset, const Nexus*nex)
  */
 
 bool NetAssignBase::synth_async(Design*des, NetScope*scope, bool sync_flag,
-				NetNet*nex_map, NetNet*nex_out)
-{
-      const perm_string tmp = perm_string::literal("tmp");
-      NetNet*stub = new NetNet(scope, tmp, NetNet::WIRE, nex_out->pin_count());
-      bool flag = synth_async(des, scope, sync_flag, nex_map, nex_out, stub);
-      delete stub;
-      return flag;
-}
-
-bool NetAssignBase::synth_async(Design*des, NetScope*scope, bool sync_flag,
+				struct sync_accounting_cell*nex_ff,
 				NetNet*nex_map, NetNet*nex_out,
 				NetNet*accum_in)
 {
@@ -160,6 +160,45 @@ bool NetAssignBase::synth_async(Design*des, NetScope*scope, bool sync_flag,
 		  return false;
 	    }
 
+	      /* Handle the special case that this is a decoded
+		 enable. generate a demux for the device, with the
+		 WriteData connected to the r-value and the Data
+		 vector connected to the feedback. */
+	    if (cur->bmux() != 0) {
+		  assert(sync_flag);
+
+		  NetNet*adr = cur->bmux()->synthesize(des);
+
+		  NetDemux*dq = new NetDemux(scope, scope->local_symbol(),
+					     lsig->pin_count(),
+					     adr->pin_count());
+		  des->add_node(dq);
+		  dq->set_line(*this);
+
+		  for (unsigned idx = 0; idx < adr->pin_count() ;  idx += 1)
+			connect(dq->pin_Address(idx), adr->pin(idx));
+
+		  assert(cur->lwidth() == 1);
+
+		  for (unsigned idx = 0; idx < lsig->pin_count(); idx += 1) {
+			unsigned off = cur->get_loff()+idx;
+			unsigned ptr = find_nexus_in_set(nex_map, lsig->pin(off).nexus());
+			assert(ptr <= nex_map->pin_count());
+			connect(nex_out->pin(ptr), dq->pin_Q(idx));
+		  }
+
+		  for (unsigned idx = 0 ;  idx < lsig->pin_count(); idx += 1)
+			connect(dq->pin_Data(idx), nex_map->pin(roff+idx));
+
+		  connect(dq->pin_WriteData(), rsig->pin(roff));
+
+		  roff += cur->lwidth();
+		  cur->turn_sig_to_wire_on_release();
+		  continue;
+	    }
+
+	      /* By this point ant bmux() has been dealt with. Panic
+		 if that is not so. */
 	    assert(! cur->bmux());
 
 	      /* Bind the outputs that we do make to the nex_out. Use the
@@ -192,7 +231,8 @@ bool NetAssignBase::synth_async(Design*des, NetScope*scope, bool sync_flag,
  * substatements.
  */
 bool NetBlock::synth_async(Design*des, NetScope*scope, bool sync_flag,
-			   NetNet*nex_map, NetNet*nex_out)
+			   struct sync_accounting_cell*nex_ff,
+			   NetNet*nex_map, NetNet*nex_out, NetNet*accum_in)
 {
       DEBUG_SYNTH2_ENTRY("NetBlock")
       if (last_ == 0) {
@@ -241,7 +281,7 @@ bool NetBlock::synth_async(Design*des, NetScope*scope, bool sync_flag,
 			connect(new_accum->pin(idx), accum_out->pin(ptr));
 	    }
 
-	    bool ok_flag = cur->synth_async(des, scope, sync_flag,
+	    bool ok_flag = cur->synth_async(des, scope, sync_flag, nex_ff,
 					    tmp_map, tmp_out, new_accum);
 	    flag = flag && ok_flag;
 
@@ -307,16 +347,7 @@ bool NetBlock::synth_async(Design*des, NetScope*scope, bool sync_flag,
 }
 
 bool NetCase::synth_async(Design*des, NetScope*scope, bool sync_flag,
-			  NetNet*nex_map, NetNet*nex_out)
-{
-      const perm_string tmp = perm_string::literal("tmp");
-      NetNet*stub = new NetNet(scope, tmp, NetNet::WIRE, nex_out->pin_count());
-      bool flag = synth_async(des, scope, sync_flag, nex_map, nex_out, stub);
-      delete stub;
-      return flag;
-}
-
-bool NetCase::synth_async(Design*des, NetScope*scope, bool sync_flag,
+			  struct sync_accounting_cell*nex_ff,
 			  NetNet*nex_map, NetNet*nex_out, NetNet*accum)
 {
       unsigned cur;
@@ -371,7 +402,7 @@ bool NetCase::synth_async(Design*des, NetScope*scope, bool sync_flag,
 	/* Handle the special case that this can be done it a smaller
 	   1-hot MUX. */
       if (nondefault_items < sel_pins)
-	    return synth_async_1hot_(des, scope, sync_flag,
+	    return synth_async_1hot_(des, scope, sync_flag, nex_ff,
 				    nex_map, nex_out, accum,
 				    esig, nondefault_items);
 
@@ -502,6 +533,7 @@ bool NetCase::synth_async(Design*des, NetScope*scope, bool sync_flag,
 		       connect all the output bits it knows how to the
 		       sig net. */
 		  statement_map[item]->synth_async(des, scope, sync_flag,
+						   nex_ff,
 						   nex_map, sig, accum);
 
 		  for (unsigned idx = 0 ;  idx < mux->width() ;  idx += 1) {
@@ -529,6 +561,7 @@ bool NetCase::synth_async(Design*des, NetScope*scope, bool sync_flag,
 }
 
 bool NetCase::synth_async_1hot_(Design*des, NetScope*scope, bool sync_flag,
+				struct sync_accounting_cell*nex_ff,
 				NetNet*nex_map, NetNet*nex_out, NetNet*accum,
 				NetNet*esig, unsigned hot_items)
 {
@@ -583,7 +616,7 @@ bool NetCase::synth_async_1hot_(Design*des, NetScope*scope, bool sync_flag,
 	    NetNet*item_sig = new NetNet(scope, scope->local_symbol(),
 					 NetNet::WIRE, nex_map->pin_count());
 	    assert(items_[item].statement);
-	    items_[item].statement->synth_async(des, scope, sync_flag,
+	    items_[item].statement->synth_async(des, scope, sync_flag, nex_ff,
 						nex_map, item_sig, accum);
 	    for (unsigned idx = 0 ;  idx < item_sig->pin_count() ;  idx += 1)
 		  connect(mux->pin_Data(idx, 1<<use_item), item_sig->pin(idx));
@@ -600,7 +633,7 @@ bool NetCase::synth_async_1hot_(Design*des, NetScope*scope, bool sync_flag,
       if (default_statement) {
 	    default_sig = new NetNet(scope, scope->local_symbol(),
 				     NetNet::WIRE, nex_map->pin_count());
-	    default_statement->synth_async(des, scope, sync_flag,
+	    default_statement->synth_async(des, scope, sync_flag, nex_ff,
 					   nex_map, default_sig, accum);
 
       }
@@ -643,27 +676,13 @@ bool NetCase::synth_async_1hot_(Design*des, NetScope*scope, bool sync_flag,
       return true;
 }
 
-/*
- * If the synth_async method is called without an accumulated input
- * (in other words not from within a block) then stub the input signal
- * with an unconnected net.
- */
-bool NetCondit::synth_async(Design*des, NetScope*scope, bool sync_flag,
-			    NetNet*nex_map, NetNet*nex_out)
-{
-      const perm_string tmp = perm_string::literal("tmp");
-      NetNet*stub = new NetNet(scope, tmp, NetNet::WIRE, nex_out->pin_count());
-      bool flag = synth_async(des, scope, sync_flag, nex_map, nex_out, stub);
-      delete stub;
-      return flag;
-}
-
 /*
  * Handle synthesis for an asynchronous condition statement. If we get
  * here, we know that the CE of a DFF has already been filled, so the
  * condition expression goes to the select of an asynchronous mux.
  */
 bool NetCondit::synth_async(Design*des, NetScope*scope, bool sync_flag,
+			    struct sync_accounting_cell*nex_ff,
 			    NetNet*nex_map, NetNet*nex_out,
 			    NetNet*accum)
 {
@@ -726,7 +745,7 @@ bool NetCondit::synth_async(Design*des, NetScope*scope, bool sync_flag,
 	    }
 
       } else {
-	    bool flag = if_->synth_async(des, scope, sync_flag,
+	    bool flag = if_->synth_async(des, scope, sync_flag, nex_ff,
 					 nex_map, asig, accum);
 	    if (!flag) {
 		  delete asig;
@@ -750,7 +769,7 @@ bool NetCondit::synth_async(Design*des, NetScope*scope, bool sync_flag,
 			connect(bsig->pin(idx), nex_map->pin(idx));
 	    }
       } else {
-	    bool flag = else_->synth_async(des, scope, sync_flag,
+	    bool flag = else_->synth_async(des, scope, sync_flag, nex_ff,
 					   nex_map, bsig, accum);
 	    if (!flag) {
 		  delete asig;
@@ -818,10 +837,11 @@ bool NetCondit::synth_async(Design*des, NetScope*scope, bool sync_flag,
 }
 
 bool NetEvWait::synth_async(Design*des, NetScope*scope, bool sync_flag,
-			    NetNet*nex_map, NetNet*nex_out)
+			    sync_accounting_cell*nex_ff,
+			    NetNet*nex_map, NetNet*nex_out, NetNet*accum_in)
 {
-      bool flag = statement_->synth_async(des, scope, sync_flag,
-					  nex_map, nex_out);
+      bool flag = statement_->synth_async(des, scope, sync_flag, nex_ff,
+					  nex_map, nex_out, accum_in);
       return flag;
 }
 
@@ -836,8 +856,8 @@ bool NetProcTop::synth_async(Design*des)
       for (unsigned idx = 0 ;  idx < nex_out->pin_count() ;  idx += 1)
 	    connect(nex_set[idx], nex_out->pin(idx));
 
-      bool flag = statement_->synth_async(des, scope(), false,
-					  nex_out, nex_out);
+      bool flag = statement_->synth_async_noaccum(des, scope(), false, 0,
+						  nex_out, nex_out);
 
       delete nex_out;
       return flag;
@@ -915,7 +935,8 @@ bool NetAssignBase::synth_sync(Design*des, NetScope*scope,
 	   assignments. */
       if (demux == 0) {
 	      /* Synthesize the input to the DFF. */
-	    return synth_async(des, scope, true, nex_map, nex_out);
+	    return synth_async_noaccum(des, scope, true, nex_ff,
+				       nex_map, nex_out);
       }
 
       assert(demux->bmux() != 0);
@@ -1256,7 +1277,8 @@ bool NetCondit::synth_sync(Design*des, NetScope*scope,
 	    asig->local_flag(true);
 
 	    assert(if_ != 0);
-	    bool flag = if_->synth_async(des, scope, true, nex_map, asig);
+	    bool flag = if_->synth_async_noaccum(des, scope, true, nex_ff,
+						 nex_map, asig);
 
 	    assert(asig->pin_count() == ff->width());
 
@@ -1347,7 +1369,8 @@ bool NetCondit::synth_sync(Design*des, NetScope*scope,
 	    NetNet*asig = new NetNet(scope, scope->local_symbol(),
 				     NetNet::WIRE, nex_map->pin_count());
 	    asig->local_flag(true);
-	    bool flag = if_->synth_async(des, scope, true, nex_map, asig);
+	    bool flag = if_->synth_async_noaccum(des, scope, true, nex_ff,
+						 nex_map, asig);
 
 	    if (!flag) {
 		  /* This path leads nowhere */
@@ -1399,7 +1422,8 @@ bool NetCondit::synth_sync(Design*des, NetScope*scope,
 	/* If this is an if/then/else, then it is likely a
 	   combinational if, and I should synthesize it that way. */
       if (if_ && else_) {
-	    bool flag = synth_async(des, scope, true, nex_map, nex_out);
+	    bool flag =synth_async_noaccum(des, scope, true, nex_ff,
+					   nex_map, nex_out);
 	    return flag;
       }
 
@@ -1531,7 +1555,8 @@ bool NetEvWait::synth_sync(Design*des, NetScope*scope,
 }
 
 bool NetWhile::synth_async(Design*des, NetScope*scope, bool sync_flag,
-			   NetNet*nex_map, NetNet*nex_out)
+			   struct sync_accounting_cell*nex_ff,
+			   NetNet*nex_map, NetNet*nex_out, NetNet*accum_in)
 {
       cerr << get_line()
 	   << ": error: Cannot synthesize for or while loops."
@@ -1671,6 +1696,9 @@ void synth2(Design*des)
 
 /*
  * $Log: synth2.cc,v $
+ * Revision 1.39.2.26  2006/03/26 23:09:24  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.39.2.25  2006/03/18 18:43:22  steve
  *  Better error messages when synthesis fails.
  *
diff --git a/t-dll-api.cc b/t-dll-api.cc
index 9a8778388..b070e72ad 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
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: t-dll-api.cc,v 1.108.2.3 2006/03/12 07:34:19 steve Exp $"
+#ident "$Id: t-dll-api.cc,v 1.108.2.4 2006/03/26 23:09:24 steve Exp $"
 #endif
 
 # include "config.h"
@@ -765,6 +765,10 @@ extern "C" ivl_nexus_t ivl_lpm_data(ivl_lpm_t net, unsigned idx)
 	    assert(idx < net->u_.arith.width);
 	    return net->u_.arith.a[idx];
 
+	  case IVL_LPM_DEMUX:
+	    assert(idx < net->u_.demux.width);
+	    return net->u_.demux.d[idx];
+
 	  case IVL_LPM_SHIFTL:
 	  case IVL_LPM_SHIFTR:
 	    assert(idx < net->u_.shift.width);
@@ -801,6 +805,10 @@ extern "C" ivl_nexus_t ivl_lpm_datab(ivl_lpm_t net, unsigned idx)
 	    assert(idx < net->u_.arith.width);
 	    return net->u_.arith.b[idx];
 
+	  case IVL_LPM_DEMUX:
+	    assert(idx < 1);
+	    return net->u_.demux.bit_in;
+
 	  default:
 	    assert(0);
 	    return 0;
@@ -939,6 +947,10 @@ extern "C" ivl_nexus_t ivl_lpm_q(ivl_lpm_t net, unsigned idx)
 	    else
 		  return net->u_.mux.q.pins[idx];
 
+	  case IVL_LPM_DEMUX:
+	    assert(idx < net->u_.demux.width);
+	    return net->u_.demux.q[idx];
+
 	  case IVL_LPM_SHIFTL:
 	  case IVL_LPM_SHIFTR:
 	    assert(idx < net->u_.shift.width);
@@ -978,6 +990,10 @@ extern "C" ivl_nexus_t ivl_lpm_select(ivl_lpm_t net, unsigned idx)
 	    else
 		  return net->u_.mux.s.pins[idx];
 
+	  case IVL_LPM_DEMUX:
+	    assert(idx < net->u_.demux.awid);
+	    return net->u_.demux.a[idx];
+
 	  case IVL_LPM_SHIFTL:
 	  case IVL_LPM_SHIFTR:
 	    assert(idx < net->u_.shift.select);
@@ -997,6 +1013,8 @@ extern "C" unsigned ivl_lpm_selects(ivl_lpm_t net)
 	  case IVL_LPM_DECODE:
 	  case IVL_LPM_MUX:
 	    return net->u_.mux.swid;
+	  case IVL_LPM_DEMUX:
+	    return net->u_.demux.awid;
 	  case IVL_LPM_SHIFTL:
 	  case IVL_LPM_SHIFTR:
 	    return net->u_.shift.select;
@@ -1013,6 +1031,7 @@ extern "C" int ivl_lpm_signed(ivl_lpm_t net)
 	  case IVL_LPM_FF:
 	  case IVL_LPM_RAM:
 	  case IVL_LPM_MUX:
+	  case IVL_LPM_DEMUX:
 	    return 0;
 	  case IVL_LPM_ADD:
 	  case IVL_LPM_CMP_EQ:
@@ -1066,6 +1085,8 @@ extern "C" unsigned ivl_lpm_width(ivl_lpm_t net)
 	  case IVL_LPM_DECODE:
 	  case IVL_LPM_MUX:
 	    return net->u_.mux.width;
+	  case IVL_LPM_DEMUX:
+	    return net->u_.demux.width;
 	  case IVL_LPM_ADD:
 	  case IVL_LPM_CMP_EQ:
 	  case IVL_LPM_CMP_GE:
@@ -1981,6 +2002,9 @@ extern "C" ivl_variable_type_t ivl_variable_type(ivl_variable_t net)
 
 /*
  * $Log: t-dll-api.cc,v $
+ * Revision 1.108.2.4  2006/03/26 23:09:24  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.108.2.3  2006/03/12 07:34:19  steve
  *  Fix the memsynth1 case.
  *
diff --git a/t-dll.cc b/t-dll.cc
index 7b9ac023e..2b5b6d5d6 100644
--- a/t-dll.cc
+++ b/t-dll.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: t-dll.cc,v 1.131.2.5 2006/03/12 07:34:19 steve Exp $"
+#ident "$Id: t-dll.cc,v 1.131.2.6 2006/03/26 23:09:24 steve Exp $"
 #endif
 
 # include "config.h"
@@ -1547,6 +1547,66 @@ ivl_lpm_t dll_target::lpm_decode_ff_(const NetDecode*net)
       return obj;
 }
 
+bool dll_target::lpm_demux(const NetDemux*net)
+{
+      unsigned idx;
+      unsigned width = net->width();
+      unsigned awid = net->awidth();
+      ivl_lpm_t obj = new struct ivl_lpm_s;
+      obj->type  = IVL_LPM_DEMUX;
+      obj->name  = net->name();
+      obj->attr  = 0;
+      obj->nattr = 0;
+      obj->scope = find_scope(des_, net->scope());
+      assert(obj->scope);
+
+      obj->u_.demux.width = width;
+      obj->u_.demux.awid  = awid;
+
+      ivl_nexus_t*tmp = new ivl_nexus_t [2*net->width() + net->awidth()];
+      obj->u_.demux.q = tmp;
+      obj->u_.demux.d = tmp + width;
+      obj->u_.demux.a = tmp + 2*width;
+
+      for (idx = 0 ;  idx < width ;  idx += 1) {
+	    const Nexus*nex = net->pin_Q(idx).nexus();
+	    assert(nex->t_cookie());
+	    obj->u_.demux.q[idx] = (ivl_nexus_t) nex->t_cookie();
+	    nexus_lpm_add(obj->u_.demux.q[idx], obj, idx,
+			  IVL_DR_STRONG, IVL_DR_STRONG);
+      }
+
+      for (idx = 0 ;  idx < width ;  idx += 1) {
+	    const Nexus*nex = net->pin_Data(idx).nexus();
+	    assert(nex->t_cookie());
+	    obj->u_.demux.d[idx] = (ivl_nexus_t) nex->t_cookie();
+	    nexus_lpm_add(obj->u_.demux.d[idx], obj, idx,
+			  IVL_DR_HiZ, IVL_DR_HiZ);
+      }
+
+      for (idx = 0 ;  idx < awid ;  idx += 1) {
+	    const Nexus*nex = net->pin_Address(idx).nexus();
+	    assert(nex->t_cookie());
+	    obj->u_.demux.a[idx] = (ivl_nexus_t) nex->t_cookie();
+	    nexus_lpm_add(obj->u_.demux.a[idx], obj, idx,
+			  IVL_DR_HiZ, IVL_DR_HiZ);
+      }
+
+      {
+	    const Nexus*nex = net->pin_WriteData().nexus();
+	    assert(nex->t_cookie());
+	    obj->u_.demux.bit_in = (ivl_nexus_t) nex->t_cookie();
+	    nexus_lpm_add(obj->u_.demux.bit_in, obj, 0,
+			  IVL_DR_HiZ, IVL_DR_HiZ);
+      }
+
+      obj->nattr = net->attr_cnt();
+      obj->attr = fill_in_attributes(net);
+
+      scope_add_lpm(obj->scope, obj);
+      return true;
+}
+
 void dll_target::lpm_ff(const NetFF*net)
 {
       ivl_lpm_t obj = new struct ivl_lpm_s;
@@ -2271,6 +2331,9 @@ extern const struct target tgt_dll = { "dll", &dll_target_obj };
 
 /*
  * $Log: t-dll.cc,v $
+ * Revision 1.131.2.6  2006/03/26 23:09:24  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.131.2.5  2006/03/12 07:34:19  steve
  *  Fix the memsynth1 case.
  *
diff --git a/t-dll.h b/t-dll.h
index e70d0468b..e7277d7a9 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
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: t-dll.h,v 1.115.2.3 2006/03/12 07:34:19 steve Exp $"
+#ident "$Id: t-dll.h,v 1.115.2.4 2006/03/26 23:09:25 steve Exp $"
 #endif
 
 # include  "target.h"
@@ -77,6 +77,7 @@ struct dll_target  : public target_t, public expr_scan_t {
       void lpm_clshift(const NetCLShift*);
       void lpm_compare(const NetCompare*);
       bool lpm_decode(const NetDecode*);
+      bool lpm_demux(const NetDemux*);
       void lpm_divide(const NetDivide*);
       void lpm_ff(const NetFF*);
       void lpm_modulo(const NetModulo*);
@@ -342,6 +343,13 @@ struct ivl_lpm_s {
 		  } s;
 	    } mux;
 
+	    struct ivl_lpm_demux_s {
+		  unsigned width;
+		  unsigned awid;
+		  ivl_nexus_t bit_in;
+		  ivl_nexus_t *q,*d,*a;
+	    } demux;
+
 	    struct ivl_lpm_shift_s {
 		  unsigned width;
 		  unsigned select;
@@ -694,6 +702,9 @@ struct ivl_variable_s {
 
 /*
  * $Log: t-dll.h,v $
+ * Revision 1.115.2.4  2006/03/26 23:09:25  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.115.2.3  2006/03/12 07:34:19  steve
  *  Fix the memsynth1 case.
  *
diff --git a/target.cc b/target.cc
index 89dc6f2ef..0b3fecdb1 100644
--- a/target.cc
+++ b/target.cc
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: target.cc,v 1.69.2.1 2006/02/19 00:11:34 steve Exp $"
+#ident "$Id: target.cc,v 1.69.2.2 2006/03/26 23:09:25 steve Exp $"
 #endif
 
 # include "config.h"
@@ -108,6 +108,13 @@ bool target_t::lpm_decode(const NetDecode*)
       return false;
 }
 
+bool target_t::lpm_demux(const NetDemux*)
+{
+      cerr << "target (" << typeid(*this).name() << "): "
+	    "Unhandled NetDemux." << endl;
+      return false;
+}
+
 void target_t::lpm_divide(const NetDivide*)
 {
       cerr << "target (" << typeid(*this).name() << "): "
@@ -427,6 +434,9 @@ void expr_scan_t::expr_binary(const NetEBinary*ex)
 
 /*
  * $Log: target.cc,v $
+ * Revision 1.69.2.2  2006/03/26 23:09:25  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.69.2.1  2006/02/19 00:11:34  steve
  *  Handle synthesis of FF vectors with l-value decoder.
  *
diff --git a/target.h b/target.h
index 2966f486c..3916566a3 100644
--- a/target.h
+++ b/target.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: target.h,v 1.65.2.1 2006/02/19 00:11:34 steve Exp $"
+#ident "$Id: target.h,v 1.65.2.2 2006/03/26 23:09:25 steve Exp $"
 #endif
 
 # include  "netlist.h"
@@ -80,6 +80,7 @@ struct target_t {
       virtual void lpm_clshift(const NetCLShift*);
       virtual void lpm_compare(const NetCompare*);
       virtual bool lpm_decode(const NetDecode*);
+      virtual bool lpm_demux(const NetDemux*);
       virtual void lpm_divide(const NetDivide*);
       virtual void lpm_modulo(const NetModulo*);
       virtual void lpm_ff(const NetFF*);
@@ -171,6 +172,9 @@ extern const struct target *target_table[];
 
 /*
  * $Log: target.h,v $
+ * Revision 1.65.2.2  2006/03/26 23:09:25  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.65.2.1  2006/02/19 00:11:34  steve
  *  Handle synthesis of FF vectors with l-value decoder.
  *
diff --git a/tgt-stub/stub.c b/tgt-stub/stub.c
index 71db83dc1..62bab132c 100644
--- a/tgt-stub/stub.c
+++ b/tgt-stub/stub.c
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: stub.c,v 1.90.2.7 2006/03/12 07:34:20 steve Exp $"
+#ident "$Id: stub.c,v 1.90.2.8 2006/03/26 23:09:25 steve Exp $"
 #endif
 
 # include "config.h"
@@ -233,6 +233,36 @@ static void show_lpm_ram(ivl_lpm_t net)
       }
 }
 
+static void show_lpm_demux(ivl_lpm_t net)
+{
+      unsigned idx;
+      unsigned width = ivl_lpm_width(net);
+      unsigned awid = ivl_lpm_selects(net);
+
+      fprintf(out, "  LPM_DEMUX %s (word-width=%u, addr-width=%u)\n",
+	      ivl_lpm_basename(net), width, awid);
+
+      for (idx = 0 ;  idx < width ;  idx += 1)
+	    fprintf(out, "    Q %u: %s\n", idx,
+		    ivl_nexus_name(ivl_lpm_q(net, idx)));
+      for (idx = 0 ;  idx < width ;  idx += 1) {
+	    ivl_nexus_t nex = ivl_lpm_data(net, idx);
+	    fprintf(out, "    Data %u: %s\n", idx,
+		    nex? ivl_nexus_name(nex) : "");
+      }
+      for (idx = 0 ;  idx < awid ;  idx += 1) {
+	    ivl_nexus_t nex = ivl_lpm_select(net, idx);
+	    fprintf(out, "    Address %u: %s\n", idx,
+		    nex? ivl_nexus_name(nex) : "");
+      }
+
+      {
+	    ivl_nexus_t nex = ivl_lpm_datab(net, 0);
+	    fprintf(out, "    WriteIn: %s\n",
+		    nex? ivl_nexus_name(nex) : "");
+      }
+}
+
 static void show_lpm(ivl_lpm_t net)
 {
       unsigned idx;
@@ -341,6 +371,10 @@ static void show_lpm(ivl_lpm_t net)
 		break;
 	  }
 
+	  case IVL_LPM_DEMUX:
+	    show_lpm_demux(net);
+	    break;
+
 	  case IVL_LPM_RAM:
 	    show_lpm_ram(net);
 	    break;
@@ -1073,6 +1107,9 @@ int target_design(ivl_design_t des)
 
 /*
  * $Log: stub.c,v $
+ * Revision 1.90.2.8  2006/03/26 23:09:25  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.90.2.7  2006/03/12 07:34:20  steve
  *  Fix the memsynth1 case.
  *
diff --git a/tgt-vvp/vvp_scope.c b/tgt-vvp/vvp_scope.c
index 7c7484f7c..89d761210 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
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: vvp_scope.c,v 1.103.2.4 2006/03/12 07:34:20 steve Exp $"
+#ident "$Id: vvp_scope.c,v 1.103.2.5 2006/03/26 23:09:26 steve Exp $"
 #endif
 
 # include  "vvp_priv.h"
@@ -402,6 +402,7 @@ static const char* draw_net_input_drive(ivl_nexus_t nex, ivl_nexus_ptr_t nptr)
 
 	  case IVL_LPM_FF:
 	  case IVL_LPM_MUX:
+	  case IVL_LPM_DEMUX:
 	    for (idx = 0 ;  idx < ivl_lpm_width(lpm) ;  idx += 1)
 		  if (ivl_lpm_q(lpm, idx) == nex) {
 		     sprintf(result, "L_%s.%s/%u",
@@ -1296,6 +1297,49 @@ static void draw_lpm_decode(ivl_lpm_t net)
       fprintf(vvp_out, ";\n");
 }
 
+/*
+ * Draw a demux as an address decoder and .decode bit slices.
+ */
+static void draw_lpm_demux(ivl_lpm_t net)
+{
+      unsigned idx;
+      unsigned width = ivl_lpm_width(net);
+
+	/* Draw a .decode/adr node to do address decoding. */
+      draw_lpm_decode(net);
+
+      for (idx = 0 ;  idx < width ;  idx += 1) {
+	    ivl_nexus_t nex;
+
+	      /* This is a demux bit slice idx */
+	    fprintf(vvp_out, "L_%s.%s/%u .demux ",
+		    vvp_mangle_id(ivl_scope_name(ivl_lpm_scope(net))),
+		    vvp_mangle_id(ivl_lpm_basename(net)), idx);
+
+	      /* Reference the address decoder... */
+	    fprintf(vvp_out, "L_%s.%s, %u, ",
+		    vvp_mangle_id(ivl_scope_name(ivl_lpm_scope(net))),
+		    vvp_mangle_id(ivl_lpm_basename(net)), idx);
+
+	      /* not-selected bit value. */
+	    nex = ivl_lpm_data(net, idx);
+	    if (nex)
+		  draw_input_from_net(nex);
+	    else
+		  fprintf(vvp_out, "C<z>");
+
+	      /* selected bit value. */
+	    fprintf(vvp_out, ", ");
+	    nex = ivl_lpm_datab(net, 0);
+	    if (nex)
+		  draw_input_from_net(nex);
+	    else
+		  fprintf(vvp_out, "C<z>");
+
+	    fprintf(vvp_out, ";\n");
+      }
+}
+
 /*
  * Draw == and != gates. This is done as XNOR functors to compare each
  * pair of bits. The result is combined with a wide and, or a NAND if
@@ -1698,6 +1742,10 @@ static void draw_lpm_in_scope(ivl_lpm_t net)
 	    draw_lpm_decode(net);
 	    return;
 
+	  case IVL_LPM_DEMUX:
+	    draw_lpm_demux(net);
+	    return;
+
 	  default:
 	    fprintf(stderr, "XXXX LPM not supported: %s.%s\n",
 		    ivl_scope_name(ivl_lpm_scope(net)), ivl_lpm_basename(net));
@@ -1821,6 +1869,9 @@ int draw_scope(ivl_scope_t net, ivl_scope_t parent)
 
 /*
  * $Log: vvp_scope.c,v $
+ * Revision 1.103.2.5  2006/03/26 23:09:26  steve
+ *  Handle asynchronous demux/bit replacements.
+ *
  * Revision 1.103.2.4  2006/03/12 07:34:20  steve
  *  Fix the memsynth1 case.
  *