From 2deb379c0648e270f01c80e1da3594ada00937f6 Mon Sep 17 00:00:00 2001
From: steve <steve>
Date: Sat, 18 Mar 2000 23:22:37 +0000
Subject: [PATCH]  Update the FF device to nexus style.

---
 t-vvm.cc        | 223 +++++++++---------------------------------------
 vvm/Makefile.in |   4 +-
 vvm/vvm_ff.cc   | 103 ++++++++++++++++++++++
 vvm/vvm_gates.h |  60 ++++++-------
 4 files changed, 168 insertions(+), 222 deletions(-)
 create mode 100644 vvm/vvm_ff.cc

diff --git a/t-vvm.cc b/t-vvm.cc
index 3458441cb..404b379be 100644
--- a/t-vvm.cc
+++ b/t-vvm.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-vvm.cc,v 1.117 2000/03/18 02:26:02 steve Exp $"
+#ident "$Id: t-vvm.cc,v 1.118 2000/03/18 23:22:37 steve Exp $"
 #endif
 
 # include  <iostream>
@@ -119,9 +119,6 @@ class target_vvm : public target_t {
       char*defn_name;
       ofstream defn;
 
-      char*delayed_name;
-      ofstream delayed;
-
       char*init_code_name;
       ofstream init_code;
 
@@ -150,7 +147,7 @@ class target_vvm : public target_t {
 
 
 target_vvm::target_vvm()
-: function_def_flag_(false), delayed_name(0), init_code_name(0)
+: function_def_flag_(false), init_code_name(0)
 {
 }
 
@@ -650,9 +647,6 @@ void target_vvm::start_design(ostream&os, const Design*mod)
       defn_name = tempnam(0, "ivldf");
       defn.open(defn_name, ios::in | ios::out | ios::trunc);
 
-      delayed_name = tempnam(0, "ivlde");
-      delayed.open(delayed_name, ios::in | ios::out | ios::trunc);
-
       init_code_name = tempnam(0, "ivlic");
       init_code.open(init_code_name, ios::in | ios::out | ios::trunc);
 
@@ -730,16 +724,6 @@ void target_vvm::end_design(ostream&os, const Design*mod)
       defn_name = 0;
       os << "// **** end definition code" << endl;
 
-      delayed.close();
-      os << "// **** Delayed code" << endl;
-      { ifstream rdelayed (delayed_name);
-	os << rdelayed.rdbuf();
-      }
-      unlink(delayed_name);
-      free(delayed_name);
-      delayed_name = 0;
-      os << "// **** end delayed code" << endl;
-
 
       os << "// **** init_code" << endl;
       init_code << "}" << endl;
@@ -928,15 +912,8 @@ string target_vvm::defn_gate_outputfun_(ostream&os,
 					const NetNode*gate,
 					unsigned gpin)
 {
-      const NetObj::Link&lnk = gate->pin(gpin);
-
-      ostrstream tmp;
-      tmp << mangle(gate->name()) << "_output_" << lnk.get_name() <<
-	    "_" << lnk.get_inst() << ends;
-      string name = tmp.str();
-
-      os << "static void " << name << "(vpip_bit_t);" << endl;
-      return name;
+      assert(0);
+      return "";
 }
 
 void target_vvm::emit_init_value_(const NetObj::Link&lnk, verinum::V val)
@@ -980,41 +957,7 @@ void target_vvm::emit_init_value_(const NetObj::Link&lnk, verinum::V val)
  */
 void target_vvm::emit_gate_outputfun_(const NetNode*gate, unsigned gpin)
 {
-      const NetObj::Link&lnk = gate->pin(gpin);
-
-      delayed << "static void " << mangle(gate->name()) <<
-	    "_output_" << lnk.get_name() << "_" << lnk.get_inst() <<
-	    "(vpip_bit_t val)" <<
-	    endl << "{" << endl;
-
-	/* The output function connects to gpin of the netlist part
-	   and causes the inputs that it is connected to to be set
-	   with the new value. */
-
-      const NetObj*cur;
-      unsigned pin;
-      gate->pin(gpin).next_link(cur, pin);
-      for ( ; cur != gate ; cur->pin(pin).next_link(cur, pin)) {
-
-	      // Skip pins that are output only.
-	    if (cur->pin(pin).get_dir() == NetObj::Link::OUTPUT)
-		  continue;
-
-	    if (cur->pin(pin).get_name() != "") {
-
-		  delayed << "      " << mangle(cur->name()) << ".set_"
-			  << cur->pin(pin).get_name() << "(" <<
-			cur->pin(pin).get_inst() << ", val);" << endl;
-
-	    } else {
-
-		  delayed << "      " << mangle(cur->name()) << ".set("
-			  << pin << ", val);" << endl;
-	    }
-
-      }
-
-      delayed << "}" << endl;
+      assert(0);
 }
 
 void target_vvm::lpm_add_sub(ostream&os, const NetAddSub*gate)
@@ -1179,16 +1122,40 @@ void target_vvm::lpm_compare(ostream&os, const NetCompare*gate)
 
 void target_vvm::lpm_ff(ostream&os, const NetFF*gate)
 {
+      string nexus;
+      unsigned ncode;
       string mname = mangle(gate->name());
-      os << "static vvm_ff<" << gate->width() << "> " << mname << ";"
-	 << endl;
+
+      os << "static vvm_ff " << mname << "(" << gate->width() << ");" << endl;
+
+	/* Connect the clock input... */
+
+      nexus = nexus_from_link(&gate->pin_Clock());
+      ncode = nexus_wire_map[nexus];
+
+      init_code << "      nexus_wire_table["<<ncode<<"].connect(&"
+		<< mname << ", " << mname << ".key_Clock());" << endl;
+
+	/* Connect the Q output pins... */
 
       for (unsigned idx = 0 ;  idx < gate->width() ;  idx += 1) {
-	    unsigned pin = gate->pin_Q(idx).get_pin();
-	    string outfun = defn_gate_outputfun_(os, gate, pin);
-	    init_code << "      " << mangle(gate->name()) <<
-		  ".config_rout(" << idx << ", &" << outfun << ");" << endl;
-	    emit_gate_outputfun_(gate, pin);
+	    nexus = nexus_from_link(&gate->pin_Q(idx));
+	    ncode = nexus_wire_map[nexus];
+
+	    init_code << "      nexus_wire_table["<<ncode<<"].connect("
+		      << mname << ".config_rout(" << idx << "));" << endl;
+      }
+
+
+	/* Connect the Data input pins... */
+
+      for (unsigned idx = 0 ;  idx < gate->width() ;  idx += 1) {
+	    nexus = nexus_from_link(&gate->pin_Data(idx));
+	    ncode = nexus_wire_map[nexus];
+
+	    init_code << "      nexus_wire_table["<<ncode<<"].connect(&"
+		      << mname << ", " << mname << ".key_Data(" << idx
+		      << "));" << endl;
       }
 }
 
@@ -2292,6 +2259,9 @@ extern const struct target tgt_vvm = {
 };
 /*
  * $Log: t-vvm.cc,v $
+ * Revision 1.118  2000/03/18 23:22:37  steve
+ *  Update the FF device to nexus style.
+ *
  * Revision 1.117  2000/03/18 02:26:02  steve
  *  Update bufz to nexus style.
  *
@@ -2332,120 +2302,5 @@ extern const struct target tgt_vvm = {
  *  drivers and resolution functions can be used, and
  *  the t-vvm module doesn't need to write a zillion
  *  output functions.
- *
- * Revision 1.107  2000/03/08 04:36:54  steve
- *  Redesign the implementation of scopes and parameters.
- *  I now generate the scopes and notice the parameters
- *  in a separate pass over the pform. Once the scopes
- *  are generated, I can process overrides and evalutate
- *  paremeters before elaboration begins.
- *
- * Revision 1.106  2000/02/29 05:20:21  steve
- *  Remove excess variable.
- *
- * Revision 1.105  2000/02/29 05:02:30  steve
- *  Handle scope of complex guards when writing case in functions.
- *
- * Revision 1.104  2000/02/24 01:57:10  steve
- *  I no longer need to declare string and number tables early.
- *
- * Revision 1.103  2000/02/23 02:56:55  steve
- *  Macintosh compilers do not support ident.
- *
- * Revision 1.102  2000/02/14 01:20:50  steve
- *  Support case in functions.
- *
- * Revision 1.101  2000/02/14 00:12:09  steve
- *  support if-else in function definitions.
- *
- * Revision 1.100  2000/02/13 19:59:33  steve
- *  Handle selecting memory words at run time.
- *
- * Revision 1.99  2000/02/13 19:18:27  steve
- *  Accept memory words as parameter to $display.
- *
- * Revision 1.98  2000/01/18 04:53:57  steve
- *  missing break is switch.
- *
- * Revision 1.97  2000/01/13 06:05:46  steve
- *  Add the XNOR operator.
- *
- * Revision 1.96  2000/01/13 05:11:25  steve
- *  Support for multiple VPI modules.
- *
- * Revision 1.95  2000/01/13 03:35:35  steve
- *  Multiplication all the way to simulation.
- *
- * Revision 1.94  2000/01/08 03:09:14  steve
- *  Non-blocking memory writes.
- *
- * Revision 1.93  2000/01/02 17:57:56  steve
- *  It is possible for node to initialize several pins of a signal.
- *
- * Revision 1.92  1999/12/17 03:38:46  steve
- *  NetConst can now hold wide constants.
- *
- * Revision 1.91  1999/12/16 02:42:15  steve
- *  Simulate carry output on adders.
- *
- * Revision 1.90  1999/12/12 19:47:54  steve
- *  Remove the useless vvm_simulation class.
- *
- * Revision 1.89  1999/12/12 06:03:14  steve
- *  Allow memories without indices in expressions.
- *
- * Revision 1.88  1999/12/05 02:24:09  steve
- *  Synthesize LPM_RAM_DQ for writes into memories.
- *
- * Revision 1.87  1999/12/02 16:58:58  steve
- *  Update case comparison (Eric Aardoom).
- *
- * Revision 1.86  1999/11/29 00:38:27  steve
- *  Properly initialize registers.
- *
- * Revision 1.85  1999/11/28 23:59:22  steve
- *  Remove useless tests for NetESignal.
- *
- * Revision 1.84  1999/11/28 23:42:03  steve
- *  NetESignal object no longer need to be NetNode
- *  objects. Let them keep a pointer to NetNet objects.
- *
- * Revision 1.83  1999/11/28 18:05:37  steve
- *  Set VPI_MODULE_PATH in the target code, if desired.
- *
- * Revision 1.82  1999/11/28 01:16:19  steve
- *  gate outputs need to set signal values.
- *
- * Revision 1.81  1999/11/28 00:56:08  steve
- *  Build up the lists in the scope of a module,
- *  and get $dumpvars to scan the scope for items.
- *
- * Revision 1.80  1999/11/27 19:07:58  steve
- *  Support the creation of scopes.
- *
- * Revision 1.79  1999/11/24 04:38:49  steve
- *  LT and GT fixes from Eric Aardoom.
- *
- * Revision 1.78  1999/11/21 01:16:51  steve
- *  Fix coding errors handling names of logic devices,
- *  and add support for buf device in vvm.
- *
- * Revision 1.77  1999/11/21 00:13:09  steve
- *  Support memories in continuous assignments.
- *
- * Revision 1.76  1999/11/14 23:43:45  steve
- *  Support combinatorial comparators.
- *
- * Revision 1.75  1999/11/14 20:24:28  steve
- *  Add support for the LPM_CLSHIFT device.
- *
- * Revision 1.74  1999/11/13 03:46:52  steve
- *  Support the LPM_MUX in vvm.
- *
- * Revision 1.73  1999/11/10 02:52:24  steve
- *  Create the vpiMemory handle type.
- *
- * Revision 1.72  1999/11/06 16:00:17  steve
- *  Put number constants into a static table.
  */
 
diff --git a/vvm/Makefile.in b/vvm/Makefile.in
index 917338b84..73174095d 100644
--- a/vvm/Makefile.in
+++ b/vvm/Makefile.in
@@ -18,7 +18,7 @@
 #    59 Temple Place - Suite 330
 #    Boston, MA 02111-1307, USA
 #
-#ident "$Id: Makefile.in,v 1.24 2000/03/18 01:26:59 steve Exp $"
+#ident "$Id: Makefile.in,v 1.25 2000/03/18 23:22:37 steve Exp $"
 #
 #
 SHELL = /bin/sh
@@ -59,7 +59,7 @@ all: libvvm.a
 	mv $*.d dep
 
 O = vvm_add_sub.o vvm_bit.o vvm_calltf.o vvm_clshift.o vvm_compare.o \
-vvm_event.o \
+vvm_event.o vvm_ff.o \
 vvm_func.o vvm_gates.o vvm_mult.o vvm_mux.o \
 vvm_nexus.o vvm_pevent.o vvm_signal.o vvm_thread.o vpip.o
 
diff --git a/vvm/vvm_ff.cc b/vvm/vvm_ff.cc
new file mode 100644
index 000000000..3684d4b27
--- /dev/null
+++ b/vvm/vvm_ff.cc
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2000 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) && !defined(macintosh)
+#ident "$Id: vvm_ff.cc,v 1.1 2000/03/18 23:22:37 steve Exp $"
+#endif
+
+# include  "vvm_gates.h"
+
+vvm_ff::vvm_ff(unsigned w)
+: width_(w)
+{
+      out_ = new vvm_nexus::drive_t[width_];
+      bits_ = new vpip_bit_t[width_*2];
+      for (unsigned idx = 0 ;  idx < width_*2 ;  idx += 1)
+	    bits_[idx] = Vx;
+}
+
+vvm_ff::~vvm_ff()
+{
+      delete[]bits_;
+      delete[]out_;
+}
+
+vvm_nexus::drive_t* vvm_ff::config_rout(unsigned idx)
+{
+      assert(idx < width_);
+      return out_+idx;
+}
+
+unsigned vvm_ff::key_Data(unsigned idx) const
+{
+      assert(idx < width_);
+      return idx+width_;
+}
+
+unsigned vvm_ff::key_Clock() const
+{
+      return 0;
+}
+
+void vvm_ff::init_Data(unsigned idx, vpip_bit_t val)
+{
+      assert(idx < width_);
+      bits_[idx+width_] = val;
+}
+
+void vvm_ff::init_Clock(unsigned, vpip_bit_t val)
+{
+      clk_ = val;
+}
+
+void vvm_ff::take_value(unsigned key, vpip_bit_t val)
+{
+      if (key == 0) {
+	    if (val == clk_)
+		  return;
+	    bool flag = posedge(clk_, val);
+	    clk_ = val;
+	    if (flag)
+		  latch_();
+	    return;
+      }
+
+      bits_[key] = val;
+}
+
+void vvm_ff::latch_()
+{
+      vpip_bit_t*q = bits_;
+      vpip_bit_t*d = bits_+width_;
+
+      for (unsigned idx = 0 ;  idx < width_ ;  idx += 1) {
+	    if (q[idx] == d[idx])
+		  continue;
+
+	    q[idx] = d[idx];
+	    out_[idx].set_value(q[idx]);
+      }
+}
+
+/*
+ * $Log: vvm_ff.cc,v $
+ * Revision 1.1  2000/03/18 23:22:37  steve
+ *  Update the FF device to nexus style.
+ *
+ */
+
diff --git a/vvm/vvm_gates.h b/vvm/vvm_gates.h
index bd8e90d68..a722a0592 100644
--- a/vvm/vvm_gates.h
+++ b/vvm/vvm_gates.h
@@ -19,7 +19,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #if !defined(WINNT) && !defined(macintosh)
-#ident "$Id: vvm_gates.h,v 1.47 2000/03/18 02:26:02 steve Exp $"
+#ident "$Id: vvm_gates.h,v 1.48 2000/03/18 23:22:37 steve Exp $"
 #endif
 
 # include  "vvm.h"
@@ -246,52 +246,37 @@ class vvm_compare  : public vvm_nexus::recvr_t {
 
 
 /*
- * This class simulates the LPM flip-flop device.
- * XXXX Inverted clock not yet supported.
+ * This class simulates the LPM flip-flop device. The vvm_ff class
+ * supports arbitrary width devices. For each output Q, there is a
+ * unique input D. The CLK input is common for all the bit lanes.
  */
-template <unsigned WIDTH> class vvm_ff {
+class vvm_ff  : public vvm_nexus::recvr_t {
 
     public:
-      explicit vvm_ff()
-	    { clk_ = Vx;
-	      for (unsigned idx = 0 ;  idx < WIDTH ;  idx += 1)
-		    q_[idx] = Vx;
-	    }
-      ~vvm_ff() { }
+      explicit vvm_ff(unsigned wid);
+      ~vvm_ff();
 
-      void init_Data(unsigned idx, vpip_bit_t val) { d_[idx] = val; }
-      void init_Clock(unsigned, vpip_bit_t val) { clk_ = val; }
+      vvm_nexus::drive_t* config_rout(unsigned idx);
 
-      void set_Clock(unsigned, vpip_bit_t val)
-	    { if (val == clk_) return;
-	      bool flag = posedge(clk_, val);
-	      clk_ = val;
-	      if (flag) latch_();
-	    }
+      unsigned key_Data(unsigned idx) const;
+      unsigned key_Clock() const;
 
-      void set_Data(unsigned idx, vpip_bit_t val)
-	    { d_[idx] = val;
-	    }
-
-      void config_rout(unsigned idx, vvm_out_event::action_t o)
-	    { out_[idx] = o;
-	    }
+      void init_Data(unsigned idx, vpip_bit_t val);
+      void init_Clock(unsigned, vpip_bit_t val);
 
     private:
-      vpip_bit_t d_[WIDTH];
-      vpip_bit_t q_[WIDTH];
+      void take_value(unsigned key, vpip_bit_t val);
+      unsigned width_;
+      vpip_bit_t*bits_;
       vpip_bit_t clk_;
 
-      vvm_out_event::action_t out_[WIDTH];
+      vvm_nexus::drive_t* out_;
 
-      void latch_()
-	    { q_ = d_;
-	      for (unsigned idx = 0 ;  idx < WIDTH ;  idx += 1)
-		    if (out_[idx]) {
-			  vvm_event*ev = new vvm_out_event(q_[idx], out_[idx]);
-			  ev->schedule();
-		    }
-	    }
+      void latch_();
+
+    private: // not implemeneted
+      vvm_ff(const vvm_ff&);
+      vvm_ff& operator= (const vvm_ff&);
 };
 
 /*
@@ -817,6 +802,9 @@ template <unsigned WIDTH> class vvm_pevent : public vvm_nexus::recvr_t {
 
 /*
  * $Log: vvm_gates.h,v $
+ * Revision 1.48  2000/03/18 23:22:37  steve
+ *  Update the FF device to nexus style.
+ *
  * Revision 1.47  2000/03/18 02:26:02  steve
  *  Update bufz to nexus style.
  *