src/edu/berkeley/fleet/slipway/Generator.java

   1 // note: got rid of funnel "fairness" code
   2 package edu.berkeley.fleet.slipway;
   3 import edu.berkeley.fleet.slipway.*;
   4 import edu.berkeley.fleet.doc.*;
   5 import edu.berkeley.fleet.api.*;
   6 import edu.berkeley.fleet.ies44.*;
   7 import edu.berkeley.fleet.*;
   8 import java.lang.reflect.*;
   9 import edu.berkeley.sbp.chr.*;
  10 import edu.berkeley.sbp.misc.*;
  11 import edu.berkeley.sbp.meta.*;
  12 import edu.berkeley.sbp.util.*;
  13 import java.util.*;
  14 import java.io.*;
  15
  16 public class Generator {
  17
  18
  19     public static class Module {
  20         private int id = 0;
  21         private final String name;
  22         public String getName() { return name; }
  23
  24         private HashSet<InstantiatedModule> instantiatedModules = new HashSet<InstantiatedModule>();
  25         private final ArrayList<Action> actions = new ArrayList<Action>();
  26
  27         // FIXME: always-alphabetical convention?
  28         private final HashMap<String,Port> ports = new HashMap<String,Port>();
  29         private final ArrayList<String> portorder = new ArrayList<String>();
  30
  31         private StringBuffer crap = new StringBuffer();
  32         private StringBuffer precrap = new StringBuffer();
  33         public void addCrap(String s) { crap.append(s); crap.append('\n'); }
  34         public void addPreCrap(String s) { precrap.append(s); precrap.append('\n'); }
  35
  36         public Module(String name) {
  37             this.name = name;
  38         }
  39
  40         public SourcePort getInputPort(String name, int width) {
  41             SourcePort ret = (SourcePort)ports.get(name);
  42             if (ret==null) ret = new SourcePort(name, width, true);
  43             return ret;
  44         }
  45         public SinkPort getOutputPort(String name, int width, String resetBehavior) {
  46             SinkPort ret = (SinkPort)ports.get(name);
  47             if (ret==null) ret = new SinkPort(name, width, true, resetBehavior);
  48             return ret;
  49         }
  50         private abstract class Port {
  51             public final String name;
  52             public String getName() { return name; }
  53             public final int width;
  54             public boolean hasLatch = false;
  55             public boolean supress = false;
  56             public boolean noAssignData = false;
  57             public boolean external;
  58             public boolean pretendDriven = false;
  59             public boolean noreg = false;
  60             public Port(String name, int width, boolean external) {
  61                 this.width = width;
  62                 this.name = name;
  63                 this.external = external;
  64                 ports.put(name, this);
  65                 if (external)
  66                     portorder.add(name);
  67             }
  68             public String getAck() { return name+"_a"; }
  69             public String getReq() { return name+"_r"; }
  70             public abstract String getInterface();
  71             public abstract String getSimpleInterface();
  72             public abstract String getDeclaration();
  73             public abstract String getAssignments();
  74         }
  75
  76         private class InstantiatedModule {
  77             public final Module module;
  78             public final int id;
  79             private final HashMap<String,Port> ports = new HashMap<String,Port>();
  80             public String getName() { return module.getName()+"_"+id; }
  81             public InstantiatedModule(Module module) {
  82                 this.module = module;
  83                 this.id = Module.this.id++;
  84                 instantiatedModules.add(this);
  85             }
  86             public void dump(PrintWriter pw) {
  87                 pw.println("  " + module.getName() + " " + getName() + "(clk");
  88                 for(String s : module.portorder)
  89                     pw.println(", " + getPort(s, module.ports.get(s).width).getSimpleInterface());
  90                 pw.println("   );");
  91             }
  92             public Port getPort(String name, int width) {
  93                 if (module.ports.get(name) instanceof SinkPort)
  94                     return getOutputPort(name, width, "");
  95                 return getInputPort(name, width);
  96             }
  97             public SinkPort getInputPort(String name, int width) {
  98                 SinkPort port = (SinkPort)ports.get(name);
  99                 if (port == null) {
 100                     port = new SinkPort(getName()+"_"+name, width, false, "");
 101                     ports.put(name, port);
 102                 }
 103                 return port;
 104             }
 105             public SourcePort getOutputPort(String name, int width, String resetBehavior) {
 106                 SourcePort port = (SourcePort)ports.get(name);
 107                 if (port == null) {
 108                     port = new SourcePort(getName()+"_"+name, width, false);
 109                     ports.put(name, port);
 110                 }
 111                 return port;
 112             }
 113         }
 114
 115         private class SourcePort extends Port {
 116             private SinkPort driven = null;
 117             public SourcePort(String name, int width, boolean external) {
 118                 super(name, width, external); }
 119             public String getInterface() { return getReq()+", "+getAck()+"_, "+name+""; }
 120             public String getSimpleInterface() { return getReq()+", "+getAck()+", "+name+""; }
 121             public String getDeclaration() {
 122                 StringBuffer sb = new StringBuffer();
 123                 if (external) {
 124                     sb.append("input "  +                 name +"_r;\n");
 125                     sb.append("output " +                 name +"_a_;\n");
 126                     sb.append("input ["+(width-1)+":0]" + name +";\n");
 127                 } else {
 128                     sb.append("wire "  +                 name +"_r;\n");
 129                     sb.append("wire ["+(width-1)+":0]" + name +";\n");
 130                 }
 131                 if (!hasLatch) {
 132                     sb.append("wire "    +                 name +"_a;\n");
 133                 } else {
 134                     sb.append("reg "    +                 name +"_a;\n");
 135                     sb.append("initial " +                name +"_a = 0;\n");
 136                 }
 137                 return sb.toString();
 138             }
 139             public String getAssignments() {
 140                 StringBuffer sb = new StringBuffer();
 141                 if (external && !pretendDriven) {
 142                     sb.append("assign " +                 name +"_a_ = " + name + "_a;\n");
 143                 }
 144                 if (driven != null) {
 145                     sb.append("assign " + driven.name +"_r = " + name + "_r;\n");
 146                     sb.append("assign " + name +"_a = " + driven.name + "_a;\n");
 147                     sb.append("assign " + driven.name +"   = " + name + ";\n");
 148                 }
 149                 return sb.toString();
 150             }
 151             public void connect(SinkPort driven) {
 152                 this.driven = driven;
 153             }
 154         }
 155         private class SinkPort extends Port {
 156             public final String resetBehavior;
 157             public SinkPort(String name, int width, boolean external, String resetBehavior) {
 158                 super(name, width, external); this.resetBehavior=resetBehavior; }
 159             public String getResetBehavior() { return resetBehavior; }
 160             public String getInterface() { return name+"_r_, "+name+"_a, "+name+"_"; }
 161             public String getSimpleInterface() { return name+"_r, "+name+"_a, "+name; }
 162             public String getDeclaration() {
 163                 StringBuffer sb = new StringBuffer();
 164                 if (external) {
 165                     sb.append("output "  +                 name +"_r_;\n");
 166                     sb.append("input "   +                 name +"_a;\n");
 167                     sb.append("output ["+(width-1)+":0]" + name +"_;\n");
 168                 } else {
 169                     sb.append("wire "   +                 name +"_a;\n");
 170                 }
 171                 if (!hasLatch) {
 172                     sb.append("wire "    +                 name +"_r;\n");
 173                     sb.append("wire   ["+(width-1)+":0]" + name +";\n");
 174                 } else {
 175                     sb.append("reg "    +                  name +"_r;\n");
 176                     sb.append("initial " +                 name +"_r = 0;\n");
 177                     if (!noreg) {
 178                         sb.append("reg    ["+(width-1)+":0]" + name +";\n");
 179                         sb.append("initial " +                 name +" = 0;\n");
 180                     }
 181                 }
 182                 return sb.toString();
 183             }
 184             public String getAssignments() {
 185                 StringBuffer sb = new StringBuffer();
 186                 if (external && !pretendDriven) {
 187                     sb.append("assign " +                  name +"_r_ = " + name + "_r;\n");
 188                     if (!noAssignData) {
 189                         sb.append("assign " +                  name +"_ = " + name + ";\n");
 190                     }
 191                 }
 192                 return sb.toString();
 193             }
 194         }
 195
 196         public void dump(PrintWriter pw) {
 197             pw.println("`include \"macros.v\"");
 198             pw.println("module "+name+"(clk");
 199             for(String name : portorder) {
 200                 Port p = ports.get(name);
 201                 pw.println("    , " + p.getInterface());
 202             }
 203             pw.println("   );");
 204             pw.println();
 205             pw.println("    input clk;");
 206             for(String name : ports.keySet()) {
 207                 Port p = ports.get(name);
 208                 pw.println("    " + p.getDeclaration());
 209             }
 210             for(String name : ports.keySet()) {
 211                 Port p = ports.get(name);
 212                 pw.println("    " + p.getAssignments());
 213             }
 214             for(InstantiatedModule m : instantiatedModules) {
 215                 m.dump(pw);
 216             }
 217             pw.println(precrap);
 218             pw.println("always @(posedge clk) begin");
 219             for(Port p : ports.values()) {
 220                 if (p instanceof SourcePort) {
 221                     SourcePort ip = (SourcePort)p;
 222                     if (ip.hasLatch && !ip.supress)
 223                         pw.println("if (!"+ip.getReq()+" && "+ip.getAck()+") "+ip.getAck()+"<=0;");
 224                 } else {
 225                     SinkPort op = (SinkPort)p;
 226                     if (op.hasLatch && !op.supress)
 227                         pw.println("if ("+op.getReq()+" && "+op.getAck()+") begin "+
 228                                    op.getReq()+"<=0; "+
 229                                    op.getResetBehavior()+" end");
 230                 }
 231             }
 232
 233             for(Action a : actions) a.dump(pw);
 234             pw.println(" begin end");
 235             pw.println("end");
 236
 237             pw.println(crap);
 238             pw.println("endmodule");
 239         }
 240
 241         private class Action {
 242             private String[]  triggers;
 243             private SourcePort[]  inports;
 244             private SinkPort[] outports;
 245             private Object[]  actions;
 246             public Action(Object[] triggers, String action) { this(triggers, new Object[] { action }); }
 247             public Action(Object[] triggers, Object[] actions) {
 248                 int numtriggers = 0;
 249                 int numinports = 0;
 250                 int numoutports = 0;
 251                 Module.this.actions.add(this);
 252                 for(int i=0; i<triggers.length; i++)
 253                     if (triggers[i] instanceof String) numtriggers++;
 254                     else if (triggers[i] instanceof SourcePort) {
 255                         numinports++;
 256                         ((Port)triggers[i]).hasLatch = true;
 257                     } else if (triggers[i] instanceof SinkPort) {
 258                         numoutports++;
 259                         ((Port)triggers[i]).hasLatch = true;
 260                     }
 261                 this.triggers = new String[numtriggers];
 262                 this.inports = new SourcePort[numinports];
 263                 this.outports = new SinkPort[numoutports];
 264                 for(int i=0; i<triggers.length; i++)
 265                     if (triggers[i] instanceof String)       this.triggers[--numtriggers] = (String)triggers[i];
 266                     else if (triggers[i] instanceof SourcePort)  this.inports[--numinports]  = (SourcePort)triggers[i];
 267                     else if (triggers[i] instanceof SinkPort) this.outports[--numoutports] = (SinkPort)triggers[i];
 268                 this.actions = actions;
 269                 for(Object o : actions)
 270                     if (o instanceof SourcePort) ((Port)o).hasLatch = true;
 271                     else if (o instanceof SinkPort) ((Port)o).hasLatch = true;
 272             }
 273             public void dump(PrintWriter pw) {
 274                 pw.print("if (1");
 275                 for(String  s  : triggers)  pw.print(" && " + s);
 276                 for(SourcePort  ip : inports)   pw.print(" && " + ip.getReq() + " && !"+ip.getAck());
 277                 for(SinkPort op : outports)  pw.print(" && !" + op.getReq() + " && !"+op.getAck());
 278                 pw.println(") begin ");
 279                 for(Object s  : this.actions) {
 280                     if (s instanceof String) pw.println(s);
 281                     else if (s instanceof SourcePort) pw.println(((SourcePort)s).getAck() + " <= 1;");
 282                     else if (s instanceof SinkPort) pw.println(((SinkPort)s).getReq() + " <= 1;");
 283                 }
 284                 pw.println("end else ");
 285             }
 286         }
 287     }
 288
 289     public static final int WORD_WIDTH = 37;
 290     public static final int DESTINATION_WIDTH = 11;
 291     public static final int PACKET_WIDTH = WORD_WIDTH + DESTINATION_WIDTH;
 292     public static final int INSTRUCTION_WIDTH = WORD_WIDTH;
 293
 294     public static void main(String[] s) throws Exception {
 295         String prefix = "src/edu/berkeley/fleet/slipway/";
 296         PrintWriter pw;
 297
 298         mkfunnel("funnel", prefix);
 299         mkhorn(    "horn", prefix, PACKET_WIDTH-1, DESTINATION_WIDTH-1, 0, 0);
 300         mkhorn(   "ihorn", prefix, PACKET_WIDTH-1, 34, 24, 0);
 301
 302         Module fifostage = mkfifo("fifostage", 0, null,      prefix);
 303         Module fifo4     = mkfifo("fifo4",     4, fifostage, prefix);
 304         Module fifoship  = mkfifo("fifo",      4, fifo4,     prefix);
 305         mkoutbox("outbox", false, prefix, fifo4);
 306         mkoutbox("inbox", true, prefix, fifo4);
 307
 308         mkkill("kill", prefix);
 309     }
 310
 311     private static Module mkkill(String name, String prefix) throws Exception {
 312         Module killm = new Module(name);
 313         Module.SourcePort  instr    = killm.getInputPort("instr",    INSTRUCTION_WIDTH);
 314         Module.SinkPort    kill     = killm.getOutputPort("kill",    INSTRUCTION_WIDTH+1, "");
 315         Module.SinkPort    notkill  = killm.getOutputPort("notkill", INSTRUCTION_WIDTH,   "");
 316         killm.addPreCrap("  reg ifull;");
 317         killm.addPreCrap("  initial ifull = 0;");
 318         killm.new Action(new Object[] { "!ifull",           instr, notkill              },
 319                          new Object[] { "notkill = instr;", instr,         "ifull = 1;" }
 320                          );
 321         killm.new Action(new Object[] { kill, "ifull",          "`instruction_is_kill(notkill)" },
 322                          new Object[] { kill, "ifull=0;",
 323                                         "kill = { `instruction_bit_kill_only_standing(notkill), `instruction_count(notkill) };" }
 324                          );
 325         killm.new Action(new Object[] { notkill, "ifull",          "!`instruction_is_kill(notkill)" },
 326                          new Object[] { notkill, "ifull=0;" }
 327                          );
 328         PrintWriter pw = new PrintWriter(new OutputStreamWriter(new FileOutputStream(prefix+"/"+name+".v")));
 329         killm.dump(pw);
 330         pw.flush();
 331         return killm;
 332     }
 333
 334     private static Module mkfunnel(String name, String prefix) throws Exception {
 335         Module funnel = new Module(name);
 336         Module.SinkPort    out = funnel.getOutputPort("out", PACKET_WIDTH, "");
 337         Module.SourcePort  in1 = funnel.getInputPort("in1", PACKET_WIDTH);
 338         Module.SourcePort  in2 = funnel.getInputPort("in2", PACKET_WIDTH);
 339         funnel.new Action(new Object[] { in1, out }, new Object[] { in1, out, "out  = in1;" });
 340         funnel.new Action(new Object[] { in2, out }, new Object[] { in2, out, "out  = in2;" });
 341         PrintWriter pw = new PrintWriter(new OutputStreamWriter(new FileOutputStream(prefix+"/"+name+".v")));
 342         funnel.dump(pw);
 343         pw.flush();
 344         return funnel;
 345     }
 346
 347     private static Module mkoutbox(String name, boolean inbox, String prefix, Module fifo) throws Exception {
 348         Module box = new Module(name);
 349         Module.SourcePort instr         = box.getInputPort("instr",       INSTRUCTION_WIDTH);
 350         //instr.hasLatch = true;
 351         //instr.supress = true;
 352         Module.SourcePort fabric_in     = box.getInputPort("fabric_in",   PACKET_WIDTH);
 353         Module.SinkPort   fabric_out    = box.getOutputPort("fabric_out", PACKET_WIDTH, "");
 354         fabric_out.hasLatch = true;
 355         //fabric_out.supress = true;
 356
 357         Module.InstantiatedModule dfifo = box.new InstantiatedModule(fifo);
 358         fabric_in.connect(dfifo.getInputPort("in", PACKET_WIDTH));
 359
 360         Module.SourcePort dfifo_out = dfifo.getOutputPort("out", PACKET_WIDTH, "");
 361         String fabric_in_d0 = dfifo_out.name;
 362         String fabric_in_r0 = fabric_in_d0+"_r";
 363         String fabric_in_a0 = fabric_in_d0+"_a";
 364         dfifo_out.hasLatch = true;
 365
 366         Module.SourcePort   ship_out    = null;
 367         if (!inbox) {
 368             ship_out = box.getInputPort("ship",        WORD_WIDTH);
 369             ship_out.hasLatch = true;
 370         }
 371
 372         Module.SinkPort   ship_in     = null;
 373         if (inbox) {
 374             ship_in = box.getOutputPort("ship",        PACKET_WIDTH, "");
 375             ship_in.hasLatch = true;
 376         }
 377
 378             box.addPreCrap("  reg[(`INSTRUCTION_WIDTH-1):0] ondeck;");
 379             box.addPreCrap("  reg[(`COUNT_WIDTH-1):0] repcount;");
 380             box.addPreCrap("  initial ondeck=0;");
 381             box.addPreCrap("  reg ondeck_full;    initial ondeck_full=0;");
 382             box.addPreCrap("  reg newmayproceed;  initial newmayproceed=1;");
 383             box.addPreCrap("  reg dorepeat;       initial dorepeat=0;");
 384             box.addPreCrap("  reg dorepeatkill;   initial dorepeatkill=0;");
 385             box.addPreCrap("  reg dokill;         initial dokill=0;");
 386             box.addPreCrap("  reg clogged;        initial clogged=0;");
 387
 388             // FIXME: destination
 389             Module.SinkPort   token_out = fabric_out;
 390             Module.SourcePort token_in  = dfifo_out;
 391             Module.SinkPort   data_out  = inbox ? ship_in   : fabric_out;
 392             Module.SourcePort data_in   = inbox ? dfifo_out : ship_out;
 393
 394             Module.InstantiatedModule ififo = box.new InstantiatedModule(fifo);
 395             Module.SinkPort ififo_in = ififo.getInputPort("in", PACKET_WIDTH);
 396             ififo_in.hasLatch = true;
 397             Module.SourcePort ififo_out = ififo.getOutputPort("out", PACKET_WIDTH, "");
 398
 399             // Clog (must be first)
 400             box.new Action(
 401                            new Object[] { ififo_out, "newmayproceed==1", "`instruction_is_clog("+ififo_out.getName()+")" },
 402                            new Object[] { ififo_out, "clogged <= 1;", "newmayproceed<=0;" }
 403                            );
 404
 405             // UnClog
 406             box.new Action(
 407                            new Object[] { instr, "clogged==1", "`instruction_is_unclog(instr)" },
 408                            new Object[] { instr, "clogged <= 0;", "newmayproceed<=1;"  }
 409                            );
 410
 411             // First Kill
 412             box.new Action(
 413                            new Object[] { instr, ififo_out, "`instruction_is_kill(instr)", "!`instruction_is_unclog(instr)", "newmayproceed==1" },
 414                            new Object[] { instr, ififo_out,
 415                                           "if (`instruction_count(instr)!=0)"+
 416                                           "  begin repcount <= `instruction_count(instr)-1; newmayproceed <= 0; "+
 417                                           "        dorepeatkill <= 1; end else begin newmayproceed<=1; end" }
 418                            );
 419
 420             // Kill
 421             box.new Action(
 422                            new Object[] { "dokill==1" },
 423                            new Object[] { "dokill<=0;",
 424                                           "if (`instruction_count(ondeck)!=0)"+
 425                                           "  begin repcount <= `instruction_count(ondeck)-1;"+
 426                                           "        dorepeatkill <= 1; end else begin newmayproceed<=1; end" }
 427                            );
 428
 429             // RepKill
 430             box.new Action(
 431                            new Object[] { "dorepeatkill==1", ififo_out },
 432                            new Object[] { "dorepeatkill<=0;", ififo_out, "dokill<=1;", "`instruction_count(ondeck)<=repcount;" }
 433                            );
 434
 435             // Enqueue
 436             box.new Action(
 437                            new Object[] { instr, ififo_in, "!`instruction_is_kill(instr)" },
 438                            new Object[] { instr, ififo_in, ififo_in.getName()+"<=instr;"  }
 439                            );
 440
 441             // New
 442             box.new Action(
 443                            new Object[] { ififo_out, "ondeck_full==0", "newmayproceed==1" },
 444                            new Object[] { ififo_out, "ondeck_full<=1;", "newmayproceed<=0;",
 445                                           "ondeck<="+ififo_out.getName()+";"  }
 446                            );
 447
 448             // RepeatExecute
 449             box.new Action(
 450                            new Object[] { "dorepeat==1", },
 451                            new Object[] { "dorepeat<=0;", "ondeck_full<=1;", "`instruction_count(ondeck)<=repcount;" }
 452                            );
 453
 454             for(int di=0; di<=1; di++)
 455                 for(int dout=0; dout<=1; dout++)
 456                     for(int tout=0; tout<=1; tout++)
 457                     for(int ti=0; ti<=1; ti++) {
 458                         box.new Action(
 459                                        new Object[] { "ondeck_full==1",
 460                                                       data_out,
 461                                                       token_out,
 462                                                       ififo_in,
 463                                                       (di==1 ? "" : "!")+"`instruction_bit_datain(ondeck)",
 464                                                       (di==1 ? data_in : "1"),
 465                                                       (ti==1 ? "" : "!")+"`instruction_bit_tokenin(ondeck)",
 466                                                       (ti==1 ? token_in : "1"),
 467                                                       (dout==1 ? "" : "!")+"`instruction_bit_dataout(ondeck)",
 468                                                       (tout==1 ? "" : "!")+"`instruction_bit_tokenout(ondeck)"
 469                                        },
 470                                        new Object[] { "ondeck_full<=0;",
 471                                                       "if (`instruction_count(ondeck)==1 || `instruction_bit_recycle(ondeck)) newmayproceed<=1;",
 472                                                       "if (`instruction_bit_recycle(ondeck) && `instruction_count(ondeck)!=1) "+
 473                                                       "    begin "+ififo_in.getName()+"<=ondeck; "+
 474                                                       "          `instruction_count("+ififo_in.getName()+")<=(`instruction_count(ondeck)==0?0:`instruction_count(ondeck)-1);"+
 475                                                       "          "+ififo_in.getReq()+"<=1; end",
 476                                                       "if (!`instruction_bit_recycle(ondeck) && `instruction_count(ondeck)!=1) "+
 477                                                       "    dorepeat <= 1;",
 478                                                       "repcount <= (`instruction_count(ondeck)==0 ? 0 : (`instruction_count(ondeck)-1));",
 479                                                       (di==1 ? data_in : ""),
 480                                                       (dout==1 ? data_out : ""),
 481                                                       (ti==1 ? token_in : ""),
 482                                                       (tout==1 ? token_out : ""),
 483                                                       ("if (`instruction_bit_latch(ondeck)) "+
 484                                                        (inbox ? data_out.getName() : "`packet_data("+data_out.getName()+")")+
 485                                                        "<="+
 486                                                        (inbox ? "`packet_data("+data_in.getName()+")" : data_in.getName())+";"),
 487                                                       (tout==1 ? "`packet_dest("+token_out.getName()+")<=`instruction_bit_dest(ondeck);" : ""),
 488                                                       (dout==1 && !inbox ? "`packet_dest("+data_out.getName()+")<=`instruction_bit_dest(ondeck);" : "")
 489                                        }
 490                                        );
 491                     }
 492
 493         PrintWriter pw = new PrintWriter(new OutputStreamWriter(new FileOutputStream(prefix+"/"+name+".v")));
 494         box.dump(pw);
 495         pw.flush();
 496         return box;
 497     }
 498
 499     private static Module mkfifo(String name, int len, Module instance, String prefix) throws Exception {
 500         Module fifo4 = new Module(name);
 501         Module.SourcePort  inx  = fifo4.getInputPort("in", PACKET_WIDTH);
 502         Module.SinkPort    outx = fifo4.getOutputPort("out", PACKET_WIDTH, "");
 503         Module.InstantiatedModule[] stages = new Module.InstantiatedModule[len];
 504         if (len==0) {
 505             fifo4.new Action(new Object[] { inx, outx }, new Object[] { inx, outx, "out  = in;" });
 506         } else for(int i=0; i<=len; i++) {
 507             if (i<len) stages[i] = fifo4.new InstantiatedModule(instance);
 508             Module.SourcePort driver = i==0 ? inx : stages[i-1].getOutputPort("out", PACKET_WIDTH, "");
 509             Module.SinkPort   driven = i==len ? outx : stages[i].getInputPort("in", PACKET_WIDTH);
 510             driver.connect(driven);
 511         }
 512         PrintWriter pw = new PrintWriter(new OutputStreamWriter(new FileOutputStream(prefix+"/"+name+".v")));
 513         fifo4.dump(pw);
 514         pw.flush();
 515         return fifo4;
 516     }
 517
 518     public static void mkhorn(String name,
 519                               String prefix,
 520                               int top,
 521                               int top_of_addr_field,
 522                               int bot_of_addr_field,
 523                               int bot) throws Exception {
 524         Module horn = new Module(name);
 525         Module.SourcePort  in   = horn.getInputPort("in", PACKET_WIDTH);
 526         Module.SinkPort out0 = horn.getOutputPort("out0", PACKET_WIDTH, "");
 527         Module.SinkPort out1 = horn.getOutputPort("out1", PACKET_WIDTH, "");
 528         String shifted_packet = "{ ";
 529         if (top_of_addr_field+1 < top) shifted_packet += " in["+top+":"+(top_of_addr_field+1)+"], ";
 530         shifted_packet += " (in["+(top_of_addr_field)+":"+bot_of_addr_field+"] >> 1) ";
 531         if (bot_of_addr_field > 0) shifted_packet += ",  in["+(bot_of_addr_field-1)+":0]  ";
 532         shifted_packet += " }";
 533         // same behavior as FLEET -- wait for both
 534         horn.new Action(new Object[] { in, out0, out1, "(in["+bot_of_addr_field+"]==0)" },
 535                         new Object[] { in, out0, "out0 = " + shifted_packet + ";" });
 536         horn.new Action(new Object[] { in, out0, out1, "(in["+bot_of_addr_field+"]==1)" },
 537                         new Object[] { in, out1, "out1 = " + shifted_packet + ";" });
 538
 539         PrintWriter pw = new PrintWriter(new OutputStreamWriter(new FileOutputStream(prefix+"/"+name+".v")));
 540         horn.dump(pw);
 541         pw.flush();
 542     }
 543
 544 }
 545
 546
 547
 548