aboutsummaryrefslogtreecommitdiffstats
path: root/quantum/process_keycode/process_unicode_common.h
diff options
context:
space:
mode:
Diffstat (limited to 'quantum/process_keycode/process_unicode_common.h')
0 files changed, 0 insertions, 0 deletions
='#n75'>75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822
/*
 *  nextpnr -- Next Generation Place and Route
 *
 *  Copyright (C) 2018  SymbioticEDA
 *
 *  jsonparse.cc -- liberally copied from the yosys file of the same name by
 *
 *  Copyright (C) 2018  Clifford Wolf <clifford@symbioticeda.com>
 *
 *  Permission to use, copy, modify, and/or distribute this software for any
 *  purpose with or without fee is hereby granted, provided that the above
 *  copyright notice and this permission notice appear in all copies.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

#include "jsonparse.h"
#include <assert.h>
#include <fstream>
#include <iostream>
#include <iterator>
#include <log.h>
#include <map>
#include <string>
#include "nextpnr.h"

NEXTPNR_NAMESPACE_BEGIN

extern bool check_all_nets_driven(Context *ctx);

namespace JsonParser {

const bool json_debug = false;

typedef std::string string;

template <typename T> int GetSize(const T &obj) { return obj.size(); }

struct JsonNode
{
    char type; // S=String, N=Number, A=Array, D=Dict
    string data_string;
    int data_number;
    std::vector<JsonNode *> data_array;
    std::map<string, JsonNode *> data_dict;
    std::vector<string> data_dict_keys;

    JsonNode(std::istream &f, int &lineno)
    {
        type = 0;
        data_number = 0;

        while (1) {
            int ch = f.get();

            if (ch == EOF)
                log_error("Unexpected EOF in JSON file.\n");

            if (ch == '\n')
                lineno++;
            if (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n')
                continue;

            if (ch == '\"') {
                type = 'S';

                while (1) {
                    ch = f.get();

                    if (ch == EOF)
                        log_error("Unexpected EOF in JSON string.\n");

                    if (ch == '\"')
                        break;

                    if (ch == '\\') {
                        int ch = f.get();

                        if (ch == EOF)
                            log_error("Unexpected EOF in JSON string.\n");
                    }

                    data_string += ch;
                }

                break;
            }

            if (('0' <= ch && ch <= '9') || ('-' == ch)) {
                type = 'N';
                if (ch == '-')
                    data_number = 0;
                else
                    data_number = ch - '0';
                data_string += ch;

                while (1) {
                    ch = f.get();

                    if (ch == EOF)
                        break;

                    if (ch == '.')
                        goto parse_real;

                    if (ch < '0' || '9' < ch) {
                        f.unget();
                        break;
                    }

                    data_number = data_number * 10 + (ch - '0');
                    data_string += ch;
                }

                if (data_string[0] == '-')
                    data_number = -data_number;
                data_string = "";
                break;

            parse_real:
                type = 'S';
                data_number = 0;
                data_string += ch;

                while (1) {
                    ch = f.get();

                    if (ch == EOF)
                        break;

                    if (ch < '0' || '9' < ch) {
                        f.unget();
                        break;
                    }

                    data_string += ch;
                }

                break;
            }

            if (ch == '[') {
                type = 'A';

                while (1) {
                    ch = f.get();

                    if (ch == EOF)
                        log_error("Unexpected EOF in JSON file.\n");

                    if (ch == '\n')
                        lineno++;
                    if (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n' || ch == ',')
                        continue;

                    if (ch == ']')
                        break;

                    f.unget();
                    data_array.push_back(new JsonNode(f, lineno));
                }

                break;
            }

            if (ch == '{') {
                type = 'D';

                while (1) {
                    ch = f.get();

                    if (ch == EOF)
                        log_error("Unexpected EOF in JSON file.\n");

                    if (ch == '\n')
                        lineno++;
                    if (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n' || ch == ',')
                        continue;

                    if (ch == '}')
                        break;

                    f.unget();
                    JsonNode key(f, lineno);

                    while (1) {
                        ch = f.get();

                        if (ch == EOF)
                            log_error("Unexpected EOF in JSON file.\n");

                        if (ch == '\n')
                            lineno++;
                        if (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n' || ch == ':')
                            continue;

                        f.unget();
                        break;
                    }

                    JsonNode *value = new JsonNode(f, lineno);

                    if (key.type != 'S')
                        log_error("Unexpected non-string key in JSON dict, line %d.\n", lineno);

                    data_dict[key.data_string] = value;
                    data_dict_keys.push_back(key.data_string);
                }

                break;
            }

            log_error("Unexpected character in JSON file, line %d: '%c'\n", lineno, ch);
        }
    }

    ~JsonNode()
    {
        for (auto it : data_array)
            delete it;
        for (auto &it : data_dict)
            delete it.second;
    }
};

void ground_net(Context *ctx, NetInfo *net)
{
    std::unique_ptr<CellInfo> cell = std::unique_ptr<CellInfo>(new CellInfo);
    PortInfo port_info;
    PortRef port_ref;

    cell->name = ctx->id(net->name.str(ctx) + ".GND");
    cell->type = ctx->id("GND");

    port_info.name = ctx->id(cell->name.str(ctx) + "[]");
    port_info.net = net;
    port_info.type = PORT_OUT;

    port_ref.cell = cell.get();
    port_ref.port = port_info.name;

    net->driver = port_ref;

    cell->ports[port_info.name] = port_info;

    ctx->cells[cell->name] = std::move(cell);
}

void vcc_net(Context *ctx, NetInfo *net)
{
    std::unique_ptr<CellInfo> cell = std::unique_ptr<CellInfo>(new CellInfo);
    PortInfo port_info;
    PortRef port_ref;

    cell->name = ctx->id(net->name.str(ctx) + ".VCC");
    cell->type = ctx->id("VCC");

    port_info.name = ctx->id(cell->name.str(ctx) + "[]");
    port_info.net = net;
    port_info.type = PORT_OUT;

    port_ref.cell = cell.get();
    port_ref.port = port_info.name;

    net->driver = port_ref;

    cell->ports[port_info.name] = port_info;

    ctx->cells[cell->name] = std::move(cell);
}

//
// is_blackbox
//
// Checks the JsonNode for an attributes dictionary, with a "blackbox" entry.
// An item is deemed to be a blackbox if this entry exists and if its
// value is not zero.  If the item is a black box, this routine will return
// true, false otherwise
bool is_blackbox(JsonNode *node)
{
    JsonNode *attr_node, *bbox_node;

    if (node->data_dict.count("attributes") == 0)
        return false;
    attr_node = node->data_dict.at("attributes");
    if (attr_node == NULL)
        return false;
    if (attr_node->type != 'D')
        return false;
    if (GetSize(attr_node->data_dict) == 0)
        return false;
    if (attr_node->data_dict.count("blackbox") == 0)
        return false;
    bbox_node = attr_node->data_dict.at("blackbox");
    if (bbox_node == NULL)
        return false;
    if (bbox_node->type != 'N')
        log_error("JSON module blackbox is not a number\n");
    if (bbox_node->data_number == 0)
        return false;
    return true;
}

void json_import_cell_params(Context *ctx, string &modname, CellInfo *cell, JsonNode *param_node,
                             std::unordered_map<IdString, std::string> *dest, int param_id)
{
    //
    JsonNode *param;
    IdString pId;
    //
    param = param_node->data_dict.at(param_node->data_dict_keys[param_id]);

    pId = ctx->id(param_node->data_dict_keys[param_id]);
    if (param->type == 'N') {
        (*dest)[pId] = std::to_string(param->data_number);
    } else if (param->type == 'S')
        (*dest)[pId] = param->data_string;
    else
        log_error("JSON parameter type of \"%s\' of cell \'%s\' not supported\n", pId.c_str(ctx),
                  cell->name.c_str(ctx));

    if (json_debug)
        log_info("    Added parameter \'%s\'=%s to cell \'%s\' "
                 "of module \'%s\'\n",
                 pId.c_str(ctx), cell->params[pId].c_str(), cell->name.c_str(ctx), modname.c_str());
}

static int const_net_idx = 0;

template <typename F>
void json_import_ports(Context *ctx, const string &modname, const std::vector<IdString> &netnames,
                       const string &obj_name, const string &port_name, JsonNode *dir_node, JsonNode *wire_group_node,
                       F visitor)
{
    // Examine a port of a cell or the design. For every bit of the port,
    // the connected net will be processed and `visitor` will be called
    // with (PortType dir, std::string name, NetInfo *net)
    assert(dir_node);

    if (json_debug)
        log_info("    Examining port %s, node %s\n", port_name.c_str(), obj_name.c_str());

    if (!wire_group_node)
        log_error("JSON no connection match "
                  "for port_direction \'%s\' of node \'%s\' "
                  "in module \'%s\'\n",
                  port_name.c_str(), obj_name.c_str(), modname.c_str());

    assert(wire_group_node);

    assert(dir_node->type == 'S');
    assert(wire_group_node->type == 'A');

    PortInfo port_info;

    port_info.name = ctx->id(port_name);
    if (dir_node->data_string.compare("input") == 0)
        port_info.type = PORT_IN;
    else if (dir_node->data_string.compare("output") == 0)
        port_info.type = PORT_OUT;
    else if (dir_node->data_string.compare("inout") == 0)
        port_info.type = PORT_INOUT;
    else
        log_error("JSON unknown port direction \'%s\' in node \'%s\' "
                  "of module \'%s\'\n",
                  dir_node->data_string.c_str(), obj_name.c_str(), modname.c_str());
    //
    // Find an update, or create a net to connect
    // to this port.
    //
    NetInfo *this_net = nullptr;
    bool is_bus;

    //
    // If this port references a bus, then there will be multiple nets
    // connected to it, all specified as part of an array.
    //
    is_bus = (wire_group_node->data_array.size() > 1);

    // Now loop through all of the connections to this port.
    if (wire_group_node->data_array.size() == 0) {
        //
        // There is/are no connections to this port.
        //
        // Create the port, but leave the net NULL

        visitor(port_info.type, port_info.name.str(ctx), nullptr);

        if (json_debug)
            log_info("      Port \'%s\' has no connection in \'%s\'\n", port_info.name.c_str(ctx), obj_name.c_str());

    } else
        for (int index = 0; index < int(wire_group_node->data_array.size()); index++) {
            //
            JsonNode *wire_node;
            PortInfo this_port;
            IdString net_id;
            //
            wire_node = wire_group_node->data_array[index];
            //
            // Pick a name for this port
            if (is_bus)
                this_port.name = ctx->id(port_info.name.str(ctx) + "[" + std::to_string(index) + "]");
            else
                this_port.name = port_info.name;
            this_port.type = port_info.type;

            if (wire_node->type == 'N') {
                int net_num;

                // A simple net, specified by a number
                net_num = wire_node->data_number;
                if (net_num < int(netnames.size()))
                    net_id = netnames.at(net_num);
                else
                    net_id = ctx->id(std::to_string(net_num));
                if (ctx->nets.count(net_id) == 0) {
                    // The net doesn't exist in the design (yet)
                    // Create in now

                    if (json_debug)
                        log_info("      Generating a new net, \'%d\'\n", net_num);

                    std::unique_ptr<NetInfo> net = std::unique_ptr<NetInfo>(new NetInfo());
                    net->name = net_id;
                    net->driver.cell = NULL;
                    net->driver.port = IdString();
                    ctx->nets[net_id] = std::move(net);

                    this_net = ctx->nets[net_id].get();
                } else {
                    //
                    // The net already exists within the design.
                    // We'll connect to it
                    //
                    this_net = ctx->nets[net_id].get();
                    if (json_debug)
                        log_info("      Reusing net \'%s\', id \'%s\', "
                                 "with driver \'%s\'\n",
                                 this_net->name.c_str(ctx), net_id.c_str(ctx),
                                 (this_net->driver.cell != NULL) ? this_net->driver.port.c_str(ctx) : "NULL");
                }

            } else if (wire_node->type == 'S') {
                // Strings are only used to drive wires for the fixed
                // values "0", "1", and "x".  Handle those constant
                // values here.
                //
                // Constants always get their own new net
                std::unique_ptr<NetInfo> net = std::unique_ptr<NetInfo>(new NetInfo());
                net->name = ctx->id("$const_" + std::to_string(const_net_idx++));

                if (wire_node->data_string.compare(string("0")) == 0) {

                    if (json_debug)
                        log_info("      Generating a constant "
                                 "zero net\n");
                    ground_net(ctx, net.get());

                } else if (wire_node->data_string.compare(string("1")) == 0) {

                    if (json_debug)
                        log_info("      Generating a constant "
                                 "one  net\n");
                    vcc_net(ctx, net.get());

                } else if (wire_node->data_string.compare(string("x")) == 0) {
                    ground_net(ctx, net.get());
                } else
                    log_error("      Unknown fixed type wire node "
                              "value, \'%s\'\n",
                              wire_node->data_string.c_str());
                IdString n = net->name;
                ctx->nets[net->name] = std::move(net);
                this_net = ctx->nets[n].get();
            }

            if (json_debug)
                log_info("    Inserting port \'%s\' into cell \'%s\'\n", this_port.name.c_str(ctx), obj_name.c_str());
            visitor(this_port.type, this_port.name.str(ctx), this_net);
        }
}

void json_import_cell(Context *ctx, string modname, const std::vector<IdString> &netnames, JsonNode *cell_node,
                      string cell_name)
{
    JsonNode *cell_type, *param_node, *attr_node;

    cell_type = cell_node->data_dict.at("type");
    if (cell_type == NULL)
        return;

    std::unique_ptr<CellInfo> cell = std::unique_ptr<CellInfo>(new CellInfo);

    cell->name = ctx->id(cell_name);
    assert(cell_type->type == 'S');
    cell->type = ctx->id(cell_type->data_string);
    // No BEL assignment here/yet

    if (json_debug)
        log_info("  Processing %s $ %s\n", modname.c_str(), cell->name.c_str(ctx));

    param_node = cell_node->data_dict.at("parameters");
    if (param_node->type != 'D')
        log_error("JSON parameter list of \'%s\' is not a data dictionary\n", cell->name.c_str(ctx));

    //
    // Loop through all parameters, adding them into the
    // design to annotate the cell
    //
    for (int paramid = 0; paramid < GetSize(param_node->data_dict_keys); paramid++) {

        json_import_cell_params(ctx, modname, cell.get(), param_node, &cell->params, paramid);
    }

    attr_node = cell_node->data_dict.at("attributes");
    if (attr_node->type != 'D')
        log_error("JSON attribute list of \'%s\' is not a data dictionary\n", cell->name.c_str(ctx));

    //
    // Loop through all attributes, adding them into the
    // design to annotate the cell
    //
    for (int attrid = 0; attrid < GetSize(attr_node->data_dict_keys); attrid++) {

        json_import_cell_params(ctx, modname, cell.get(), attr_node, &cell->attrs, attrid);
    }

    //
    // Now connect the ports of this module.  The ports are defined by
    // both the port directions node as well as the connections node.
    // Both should contain dictionaries having the same keys.
    //

    JsonNode *pdir_node = NULL;
    if (cell_node->data_dict.count("port_directions") > 0) {

        pdir_node = cell_node->data_dict.at("port_directions");
        if (pdir_node->type != 'D')
            log_error("JSON port_directions node of \'%s\' "
                      "in module \'%s\' is not a "
                      "dictionary\n",
                      cell->name.c_str(ctx), modname.c_str());

    } else if (cell_node->data_dict.count("ports") > 0) {
        pdir_node = cell_node->data_dict.at("ports");
        if (pdir_node->type != 'D')
            log_error("JSON ports node of \'%s\' "
                      "in module \'%s\' is not a "
                      "dictionary\n",
                      cell->name.c_str(ctx), modname.c_str());
    }

    JsonNode *connections = cell_node->data_dict.at("connections");
    if (connections->type != 'D')
        log_error("JSON connections node of \'%s\' "
                  "in module \'%s\' is not a "
                  "dictionary\n",
                  cell->name.c_str(ctx), modname.c_str());

    if (GetSize(pdir_node->data_dict_keys) != GetSize(connections->data_dict_keys))
        log_error("JSON number of connections doesnt "
                  "match number of ports in node \'%s\' "
                  "of module \'%s\'\n",
                  cell->name.c_str(ctx), modname.c_str());

    //
    // Loop through all of the ports of this logic element
    //
    for (int portid = 0; portid < GetSize(pdir_node->data_dict_keys); portid++) {
        //
        string port_name;
        JsonNode *dir_node, *wire_group_node;
        //

        port_name = pdir_node->data_dict_keys[portid];
        dir_node = pdir_node->data_dict.at(port_name);
        wire_group_node = connections->data_dict.at(port_name);

        json_import_ports(ctx, modname, netnames, cell->name.str(ctx), port_name, dir_node, wire_group_node,
                          [&cell, ctx](PortType type, const std::string &name, NetInfo *net) {
                              cell->ports[ctx->id(name)] = PortInfo{ctx->id(name), net, type};
                              PortRef pr;
                              pr.cell = cell.get();
                              pr.port = ctx->id(name);
                              if (net != nullptr) {
                                  if (type == PORT_IN || type == PORT_INOUT) {
                                      net->users.push_back(pr);
                                  } else if (type == PORT_OUT) {
                                      if (net->driver.cell != nullptr)
                                          log_error("multiple drivers on net '%s' (%s.%s and %s.%s)\n",
                                                    net->name.c_str(ctx), net->driver.cell->name.c_str(ctx),
                                                    net->driver.port.c_str(ctx), pr.cell->name.c_str(ctx),
                                                    pr.port.c_str(ctx));
                                      net->driver = pr;
                                  }
                              }
                          });
    }

    ctx->cells[cell->name] = std::move(cell);
    // check_all_nets_driven(ctx);
}

static void insert_iobuf(Context *ctx, NetInfo *net, PortType type, const string &name)
{
    // Instantiate a architecture-independent IO buffer connected to a given
    // net, of a given type, and named after the IO port.
    //
    // During packing, this generic IO buffer will be converted to an
    // architecure primitive.
    //
    std::unique_ptr<CellInfo> iobuf = std::unique_ptr<CellInfo>(new CellInfo());
    iobuf->name = ctx->id(name);
    std::copy(net->attrs.begin(), net->attrs.end(), std::inserter(iobuf->attrs, iobuf->attrs.begin()));
    if (type == PORT_IN) {
        if (ctx->verbose)
            log_info("processing input port %s\n", name.c_str());
        iobuf->type = ctx->id("$nextpnr_ibuf");
        iobuf->ports[ctx->id("O")] = PortInfo{ctx->id("O"), net, PORT_OUT};
        // Special case: input, etc, directly drives inout
        if (net->driver.cell != nullptr) {
            if (net->driver.cell->type != ctx->id("$nextpnr_iobuf"))
                log_error("Top-level input '%s' also driven by %s.%s.\n", name.c_str(),
                          net->driver.cell->name.c_str(ctx), net->driver.port.c_str(ctx));
            net = net->driver.cell->ports.at(ctx->id("I")).net;
        }
        assert(net->driver.cell == nullptr);
        net->driver.port = ctx->id("O");
        net->driver.cell = iobuf.get();
    } else if (type == PORT_OUT) {
        if (ctx->verbose)
            log_info("processing output port %s\n", name.c_str());
        iobuf->type = ctx->id("$nextpnr_obuf");
        iobuf->ports[ctx->id("I")] = PortInfo{ctx->id("I"), net, PORT_IN};
        PortRef ref;
        ref.cell = iobuf.get();
        ref.port = ctx->id("I");
        net->users.push_back(ref);
    } else if (type == PORT_INOUT) {
        if (ctx->verbose)
            log_info("processing inout port %s\n", name.c_str());
        iobuf->type = ctx->id("$nextpnr_iobuf");
        iobuf->ports[ctx->id("I")] = PortInfo{ctx->id("I"), nullptr, PORT_IN};

        // Split the input and output nets for bidir ports
        std::unique_ptr<NetInfo> net2 = std::unique_ptr<NetInfo>(new NetInfo());
        net2->name = ctx->id("$" + net->name.str(ctx) + "$iobuf_i");
        net2->driver = net->driver;
        if (net->driver.cell != nullptr) {
            net2->driver.cell->ports[net2->driver.port].net = net2.get();
            net->driver.cell = nullptr;
        }
        iobuf->ports[ctx->id("I")].net = net2.get();
        PortRef ref;
        ref.cell = iobuf.get();
        ref.port = ctx->id("I");
        net2->users.push_back(ref);
        ctx->nets[net2->name] = std::move(net2);

        iobuf->ports[ctx->id("O")] = PortInfo{ctx->id("O"), net, PORT_OUT};
        assert(net->driver.cell == nullptr);
        net->driver.port = ctx->id("O");
        net->driver.cell = iobuf.get();
    } else {
        assert(false);
    }
    ctx->cells[iobuf->name] = std::move(iobuf);
}

void json_import_toplevel_port(Context *ctx, const string &modname, const std::vector<IdString> &netnames,
                               const string &portname, JsonNode *node)
{
    JsonNode *dir_node = node->data_dict.at("direction");
    JsonNode *nets_node = node->data_dict.at("bits");
    json_import_ports(
            ctx, modname, netnames, "Top Level IO", portname, dir_node, nets_node,
            [ctx](PortType type, const std::string &name, NetInfo *net) { insert_iobuf(ctx, net, type, name); });
}

void json_import(Context *ctx, string modname, JsonNode *node)
{
    if (is_blackbox(node))
        return;

    log_info("Importing module %s\n", modname.c_str());

    // Multiple labels might refer to the same net. For now we resolve conflicts thus:
    //  - names with fewer $ are always prefered
    //  - between equal $ counts, fewer .s are prefered
    //  - ties are resolved alphabetically
    auto prefer_netlabel = [](const std::string &a, const std::string &b) {
        if (b.empty())
            return true;
        long a_dollars = std::count(a.begin(), a.end(), '$'), b_dollars = std::count(b.begin(), b.end(), '$');
        if (a_dollars < b_dollars)
            return true;
        else if (a_dollars > b_dollars)
            return false;
        long a_dots = std::count(a.begin(), a.end(), '.'), b_dots = std::count(b.begin(), b.end(), '.');
        if (a_dots < b_dots)
            return true;
        else if (a_dots > b_dots)
            return false;
        return a < b;
    };

    // Import netnames
    std::vector<std::string> netlabels;
    if (node->data_dict.count("netnames")) {
        JsonNode *cell_parent = node->data_dict.at("netnames");
        for (int nnid = 0; nnid < GetSize(cell_parent->data_dict_keys); nnid++) {
            JsonNode *here;

            here = cell_parent->data_dict.at(cell_parent->data_dict_keys[nnid]);
            std::string basename = cell_parent->data_dict_keys[nnid];
            if (here->data_dict.count("bits")) {
                JsonNode *bits = here->data_dict.at("bits");
                assert(bits->type == 'A');
                size_t num_bits = bits->data_array.size();
                for (size_t i = 0; i < num_bits; i++) {
                    int netid = bits->data_array.at(i)->data_number;
                    if (netid >= int(netlabels.size()))
                        netlabels.resize(netid + 1);
                    std::string name =
                            basename + (num_bits == 1 ? "" : std::string("[") + std::to_string(i) + std::string("]"));
                    if (prefer_netlabel(name, netlabels.at(netid)))
                        netlabels.at(netid) = name;
                }
            }
        }
    }
    std::vector<IdString> netids;
    std::transform(netlabels.begin(), netlabels.end(), std::back_inserter(netids),
                   [ctx](const std::string &s) { return ctx->id(s); });
    if (node->data_dict.count("cells")) {
        JsonNode *cell_parent = node->data_dict.at("cells");
        //
        //
        // Loop through all of the logic elements in a flattened design
        //
        //
        for (int cellid = 0; cellid < GetSize(cell_parent->data_dict_keys); cellid++) {
            JsonNode *here = cell_parent->data_dict.at(cell_parent->data_dict_keys[cellid]);
            json_import_cell(ctx, modname, netids, here, cell_parent->data_dict_keys[cellid]);
        }
    }

    if (node->data_dict.count("ports")) {
        JsonNode *ports_parent = node->data_dict.at("ports");

        // N.B. ports must be imported after cells for tristate behaviour
        // to be correct
        // Loop through all ports, first non-tristate then tristate to handle
        // interconnected ports correctly
        for (int portid = 0; portid < GetSize(ports_parent->data_dict_keys); portid++) {
            JsonNode *here;

            here = ports_parent->data_dict.at(ports_parent->data_dict_keys[portid]);
            JsonNode *dir_node = here->data_dict.at("direction");
            NPNR_ASSERT(dir_node->type == 'S');
            if (dir_node->data_string == "inout")
                continue;
            json_import_toplevel_port(ctx, modname, netids, ports_parent->data_dict_keys[portid], here);
        }
        for (int portid = 0; portid < GetSize(ports_parent->data_dict_keys); portid++) {
            JsonNode *here;

            here = ports_parent->data_dict.at(ports_parent->data_dict_keys[portid]);
            JsonNode *dir_node = here->data_dict.at("direction");
            NPNR_ASSERT(dir_node->type == 'S');
            if (dir_node->data_string != "inout")
                continue;
            json_import_toplevel_port(ctx, modname, netids, ports_parent->data_dict_keys[portid], here);
        }
    }
    check_all_nets_driven(ctx);
}
}; // End Namespace JsonParser

bool parse_json_file(std::istream &f, std::string &filename, Context *ctx)
{
    try {
        using namespace JsonParser;

        if (!f)
            log_error("failed to open JSON file.\n");

        int lineno = 1;

        JsonNode root(f, lineno);

        if (root.type != 'D')
            log_error("JSON root node is not a dictionary.\n");

        if (root.data_dict.count("modules") != 0) {
            JsonNode *modules = root.data_dict.at("modules");

            if (modules->type != 'D')
                log_error("JSON modules node is not a dictionary.\n");

            for (auto &it : modules->data_dict)
                json_import(ctx, it.first, it.second);
        }

        log_info("Checksum: 0x%08x\n", ctx->checksum());
        log_break();
        ctx->settings.emplace(ctx->id("input/json"), filename);
        return true;
    } catch (log_execution_error_exception) {
        return false;
    }
}

NEXTPNR_NAMESPACE_END