blif.cc

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/*
 *  yosys -- Yosys Open SYnthesis Suite
 *
 *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
 *  
 *  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.
 *
 */

// [[CITE]] Berkeley Logic Interchange Format (BLIF)
// University of California. Berkeley. July 28, 1992
// http://www.ece.cmu.edu/~ee760/760docs/blif.pdf

#include "kernel/rtlil.h"
#include "kernel/register.h"
#include "kernel/sigtools.h"
#include "kernel/celltypes.h"
#include "kernel/log.h"
#include <string>

USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN

struct BlifDumperConfig
{
    bool icells_mode;
    bool conn_mode;
    bool impltf_mode;
    bool gates_mode;
    bool param_mode;
    bool blackbox_mode;

    std::string buf_type, buf_in, buf_out;
    std::map<RTLIL::IdString, std::pair<RTLIL::IdString, RTLIL::IdString>> unbuf_types;
    std::string true_type, true_out, false_type, false_out, undef_type, undef_out;

    BlifDumperConfig() : icells_mode(false), conn_mode(false), impltf_mode(false), gates_mode(false), param_mode(false), blackbox_mode(false) { }
};

struct BlifDumper
{
    std::ostream &f;
    RTLIL::Module *module;
    RTLIL::Design *design;
    BlifDumperConfig *config;
    CellTypes ct;

    BlifDumper(std::ostream &f, RTLIL::Module *module, RTLIL::Design *design, BlifDumperConfig *config) :
            f(f), module(module), design(design), config(config), ct(design)
    {
    }

    std::vector<std::string> cstr_buf;

    const char *cstr(RTLIL::IdString id)
    {
        std::string str = RTLIL::unescape_id(id);
        for (size_t i = 0; i < str.size(); i++)
            if (str[i] == '#' || str[i] == '=')
                str[i] = '?';
        cstr_buf.push_back(str);
        return cstr_buf.back().c_str();
    }

    const char *cstr(RTLIL::SigBit sig)
    {
        if (sig.wire == NULL) {
            if (sig == RTLIL::State::S0) return config->false_type == "-" ? config->false_out.c_str() : "$false";
            if (sig == RTLIL::State::S1) return config->true_type == "-" ? config->true_out.c_str() : "$true";
            return config->undef_type == "-" ? config->undef_out.c_str() : "$undef";
        }

        std::string str = RTLIL::unescape_id(sig.wire->name);
        for (size_t i = 0; i < str.size(); i++)
            if (str[i] == '#' || str[i] == '=')
                str[i] = '?';

        if (sig.wire->width != 1)
            str += stringf("[%d]", sig.offset);

        cstr_buf.push_back(str);
        return cstr_buf.back().c_str();
    }

    const char *subckt_or_gate(std::string cell_type)
    {
        if (!config->gates_mode)
            return "subckt";
        if (!design->modules_.count(RTLIL::escape_id(cell_type)))
            return "gate";
        if (design->modules_.at(RTLIL::escape_id(cell_type))->get_bool_attribute("\\blackbox"))
            return "gate";
        return "subckt";
    }

    void dump()
    {
        f << stringf("\n");
        f << stringf(".model %s\n", cstr(module->name));

        std::map<int, RTLIL::Wire*> inputs, outputs;

        for (auto &wire_it : module->wires_) {
            RTLIL::Wire *wire = wire_it.second;
            if (wire->port_input)
                inputs[wire->port_id] = wire;
            if (wire->port_output)
                outputs[wire->port_id] = wire;
        }

        f << stringf(".inputs");
        for (auto &it : inputs) {
            RTLIL::Wire *wire = it.second;
            for (int i = 0; i < wire->width; i++)
                f << stringf(" %s", cstr(RTLIL::SigSpec(wire, i)));
        }
        f << stringf("\n");

        f << stringf(".outputs");
        for (auto &it : outputs) {
            RTLIL::Wire *wire = it.second;
            for (int i = 0; i < wire->width; i++)
                f << stringf(" %s", cstr(RTLIL::SigSpec(wire, i)));
        }
        f << stringf("\n");

        if (module->get_bool_attribute("\\blackbox")) {
            f << stringf(".blackbox\n");
            f << stringf(".end\n");
            return;
        }

        if (!config->impltf_mode) {
            if (!config->false_type.empty()) {
                if (config->false_type != "-")
                    f << stringf(".%s %s %s=$false\n", subckt_or_gate(config->false_type),
                            config->false_type.c_str(), config->false_out.c_str());
            } else
                f << stringf(".names $false\n");
            if (!config->true_type.empty()) {
                if (config->true_type != "-")
                    f << stringf(".%s %s %s=$true\n", subckt_or_gate(config->true_type),
                            config->true_type.c_str(), config->true_out.c_str());
            } else
                f << stringf(".names $true\n1\n");
            if (!config->undef_type.empty()) {
                if (config->undef_type != "-")
                    f << stringf(".%s %s %s=$undef\n", subckt_or_gate(config->undef_type),
                            config->undef_type.c_str(), config->undef_out.c_str());
            } else
                f << stringf(".names $undef\n");
        }

        for (auto &cell_it : module->cells_)
        {
            RTLIL::Cell *cell = cell_it.second;

            if (config->unbuf_types.count(cell->type)) {
                auto portnames = config->unbuf_types.at(cell->type);
                f << stringf(".names %s %s\n1 1\n",
                        cstr(cell->getPort(portnames.first)), cstr(cell->getPort(portnames.second)));
                continue;
            }

            if (!config->icells_mode && cell->type == "$_NOT_") {
                f << stringf(".names %s %s\n0 1\n",
                        cstr(cell->getPort("\\A")), cstr(cell->getPort("\\Y")));
                continue;
            }

            if (!config->icells_mode && cell->type == "$_AND_") {
                f << stringf(".names %s %s %s\n11 1\n",
                        cstr(cell->getPort("\\A")), cstr(cell->getPort("\\B")), cstr(cell->getPort("\\Y")));
                continue;
            }

            if (!config->icells_mode && cell->type == "$_OR_") {
                f << stringf(".names %s %s %s\n1- 1\n-1 1\n",
                        cstr(cell->getPort("\\A")), cstr(cell->getPort("\\B")), cstr(cell->getPort("\\Y")));
                continue;
            }

            if (!config->icells_mode && cell->type == "$_XOR_") {
                f << stringf(".names %s %s %s\n10 1\n01 1\n",
                        cstr(cell->getPort("\\A")), cstr(cell->getPort("\\B")), cstr(cell->getPort("\\Y")));
                continue;
            }

            if (!config->icells_mode && cell->type == "$_MUX_") {
                f << stringf(".names %s %s %s %s\n1-0 1\n-11 1\n",
                        cstr(cell->getPort("\\A")), cstr(cell->getPort("\\B")),
                        cstr(cell->getPort("\\S")), cstr(cell->getPort("\\Y")));
                continue;
            }

            if (!config->icells_mode && cell->type == "$_DFF_N_") {
                f << stringf(".latch %s %s fe %s\n",
                        cstr(cell->getPort("\\D")), cstr(cell->getPort("\\Q")), cstr(cell->getPort("\\C")));
                continue;
            }

            if (!config->icells_mode && cell->type == "$_DFF_P_") {
                f << stringf(".latch %s %s re %s\n",
                        cstr(cell->getPort("\\D")), cstr(cell->getPort("\\Q")), cstr(cell->getPort("\\C")));
                continue;
            }

            if (!config->icells_mode && cell->type == "$lut") {
                f << stringf(".names");
                auto &inputs = cell->getPort("\\A");
                auto width = cell->parameters.at("\\WIDTH").as_int();
                log_assert(inputs.size() == width);
                for (int i = 0; i < inputs.size(); i++) {
                    f << stringf(" %s", cstr(inputs.extract(i, 1)));
                }
                auto &output = cell->getPort("\\Y");
                log_assert(output.size() == 1);
                f << stringf(" %s", cstr(output));
                f << stringf("\n");
                auto mask = cell->parameters.at("\\LUT").as_string();
                for (int i = 0; i < (1 << width); i++) {
                    if (mask[i] == '0') continue;
                    for (int j = width-1; j >= 0; j--) {
                        f << ((i>>j)&1 ? '1' : '0');
                    }
                    f << stringf(" %c\n", mask[i]);
                }
                continue;
            }

            f << stringf(".%s %s", subckt_or_gate(cell->type.str()), cstr(cell->type));
            for (auto &conn : cell->connections())
            for (int i = 0; i < conn.second.size(); i++) {
                if (conn.second.size() == 1)
                    f << stringf(" %s", cstr(conn.first));
                else
                    f << stringf(" %s[%d]", cstr(conn.first), i);
                f << stringf("=%s", cstr(conn.second.extract(i, 1)));
            }
            f << stringf("\n");

            if (config->param_mode)
                for (auto &param : cell->parameters) {
                    f << stringf(".param %s ", RTLIL::id2cstr(param.first));
                    if (param.second.flags & RTLIL::CONST_FLAG_STRING) {
                        std::string str = param.second.decode_string();
                        f << stringf("\"");
                        for (char ch : str)
                            if (ch == '"' || ch == '\\')
                                f << stringf("\\%c", ch);
                            else if (ch < 32 || ch >= 127)
                                f << stringf("\\%03o", ch);
                            else
                                f << stringf("%c", ch);
                        f << stringf("\"\n");
                    } else
                        f << stringf("%s\n", param.second.as_string().c_str());
                }
        }

        for (auto &conn : module->connections())
        for (int i = 0; i < conn.first.size(); i++)
            if (config->conn_mode)
                f << stringf(".conn %s %s\n", cstr(conn.second.extract(i, 1)), cstr(conn.first.extract(i, 1)));
            else if (!config->buf_type.empty())
                f << stringf(".%s %s %s=%s %s=%s\n", subckt_or_gate(config->buf_type), config->buf_type.c_str(), config->buf_in.c_str(), cstr(conn.second.extract(i, 1)),
                        config->buf_out.c_str(), cstr(conn.first.extract(i, 1)));
            else
                f << stringf(".names %s %s\n1 1\n", cstr(conn.second.extract(i, 1)), cstr(conn.first.extract(i, 1)));


        f << stringf(".end\n");
    }

    static void dump(std::ostream &f, RTLIL::Module *module, RTLIL::Design *design, BlifDumperConfig &config)
    {
        BlifDumper dumper(f, module, design, &config);
        dumper.dump();
    }
};

struct BlifBackend : public Backend {
    BlifBackend() : Backend("blif", "write design to BLIF file") { }
    virtual void help()
    {
        //   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
        log("\n");
        log("    write_blif [options] [filename]\n");
        log("\n");
        log("Write the current design to an BLIF file.\n");
        log("\n");
        log("    -top top_module\n");
        log("        set the specified module as design top module\n");
        log("\n");
        log("    -buf <cell-type> <in-port> <out-port>\n");
        log("        use cells of type <cell-type> with the specified port names for buffers\n");
        log("\n");
        log("    -unbuf <cell-type> <in-port> <out-port>\n");
        log("        replace buffer cells with the specified name and port names with\n");
        log("        a .names statement that models a buffer\n");
        log("\n");
        log("    -true <cell-type> <out-port>\n");
        log("    -false <cell-type> <out-port>\n");
        log("    -undef <cell-type> <out-port>\n");
        log("        use the specified cell types to drive nets that are constant 1, 0, or\n");
        log("        undefined. when '-' is used as <cell-type>, then <out-port> specifies\n");
        log("        the wire name to be used for the constant signal and no cell driving\n");
        log("        that wire is generated.\n");
        log("\n");
        log("The following options can be useful when the generated file is not going to be\n");
        log("read by a BLIF parser but a custom tool. It is recommended to not name the output\n");
        log("file *.blif when any of this options is used.\n");
        log("\n");
        log("    -icells\n");
        log("        do not translate Yosys's internal gates to generic BLIF logic\n");
        log("        functions. Instead create .subckt or .gate lines for all cells.\n");
        log("\n");
        log("    -gates\n");
        log("        print .gate instead of .subckt lines for all cells that are not\n");
        log("        instantiations of other modules from this design.\n");
        log("\n");
        log("    -conn\n");
        log("        do not generate buffers for connected wires. instead use the\n");
        log("        non-standard .conn statement.\n");
        log("\n");
        log("    -param\n");
        log("        use the non-standard .param statement to write module parameters\n");
        log("\n");
        log("    -blackbox\n");
        log("        write blackbox cells with .blackbox statement.\n");
        log("\n");
        log("    -impltf\n");
        log("        do not write definitions for the $true, $false and $undef wires.\n");
        log("\n");
    }
    virtual void execute(std::ostream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
    {
        std::string top_module_name;
        std::string buf_type, buf_in, buf_out;
        std::string true_type, true_out;
        std::string false_type, false_out;
        BlifDumperConfig config;

        log_header("Executing BLIF backend.\n");

        size_t argidx;
        for (argidx = 1; argidx < args.size(); argidx++)
        {
            if (args[argidx] == "-top" && argidx+1 < args.size()) {
                top_module_name = args[++argidx];
                continue;
            }
            if (args[argidx] == "-buf" && argidx+3 < args.size()) {
                config.buf_type = args[++argidx];
                config.buf_in = args[++argidx];
                config.buf_out = args[++argidx];
                continue;
            }
            if (args[argidx] == "-unbuf" && argidx+3 < args.size()) {
                RTLIL::IdString unbuf_type = RTLIL::escape_id(args[++argidx]);
                RTLIL::IdString unbuf_in = RTLIL::escape_id(args[++argidx]);
                RTLIL::IdString unbuf_out = RTLIL::escape_id(args[++argidx]);
                config.unbuf_types[unbuf_type] = std::pair<RTLIL::IdString, RTLIL::IdString>(unbuf_in, unbuf_out);
                continue;
            }
            if (args[argidx] == "-true" && argidx+2 < args.size()) {
                config.true_type = args[++argidx];
                config.true_out = args[++argidx];
                continue;
            }
            if (args[argidx] == "-false" && argidx+2 < args.size()) {
                config.false_type = args[++argidx];
                config.false_out = args[++argidx];
                continue;
            }
            if (args[argidx] == "-undef" && argidx+2 < args.size()) {
                config.undef_type = args[++argidx];
                config.undef_out = args[++argidx];
                continue;
            }
            if (args[argidx] == "-icells") {
                config.icells_mode = true;
                continue;
            }
            if (args[argidx] == "-gates") {
                config.gates_mode = true;
                continue;
            }
            if (args[argidx] == "-conn") {
                config.conn_mode = true;
                continue;
            }
            if (args[argidx] == "-param") {
                config.param_mode = true;
                continue;
            }
            if (args[argidx] == "-blackbox") {
                config.blackbox_mode = true;
                continue;
            }
            if (args[argidx] == "-impltf") {
                config.impltf_mode = true;
                continue;
            }
            break;
        }
        extra_args(f, filename, args, argidx);

        if (top_module_name.empty())
            for (auto & mod_it:design->modules_)
                if (mod_it.second->get_bool_attribute("\\top"))
                    top_module_name = mod_it.first.str();

        *f << stringf("# Generated by %s\n", yosys_version_str);

        std::vector<RTLIL::Module*> mod_list;

        for (auto module_it : design->modules_)
        {
            RTLIL::Module *module = module_it.second;
            if (module->get_bool_attribute("\\blackbox") && !config.blackbox_mode)
                continue;

            if (module->processes.size() != 0)
                log_error("Found unmapped processes in module %s: unmapped processes are not supported in BLIF backend!\n", RTLIL::id2cstr(module->name));
            if (module->memories.size() != 0)
                log_error("Found munmapped emories in module %s: unmapped memories are not supported in BLIF backend!\n", RTLIL::id2cstr(module->name));

            if (module->name == RTLIL::escape_id(top_module_name)) {
                BlifDumper::dump(*f, module, design, config);
                top_module_name.clear();
                continue;
            }

            mod_list.push_back(module);
        }

        if (!top_module_name.empty())
            log_error("Can't find top module `%s'!\n", top_module_name.c_str());

        for (auto module : mod_list)
            BlifDumper::dump(*f, module, design, config);
    }
} BlifBackend;

PRIVATE_NAMESPACE_END