Various improvements in BLIF front-end
authorClifford Wolf <clifford@clifford.at>
Sun, 20 Dec 2015 12:12:24 +0000 (13:12 +0100)
committerClifford Wolf <clifford@clifford.at>
Sun, 20 Dec 2015 12:12:24 +0000 (13:12 +0100)
frontends/blif/blifparse.cc
frontends/blif/blifparse.h

index 9f2e08df0b4903b6a8b3ce08a78af09caee21e6b..2029584960d14311be6a9c754079a6b03bcfca06 100644 (file)
@@ -49,11 +49,42 @@ static bool read_next_line(char *&buffer, size_t &buffer_size, int &line_count,
        }
 }
 
-void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
+void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name, bool run_clean)
 {
        RTLIL::Module *module = nullptr;
        RTLIL::Const *lutptr = NULL;
        RTLIL::State lut_default_state = RTLIL::State::Sx;
+       int blif_maxnum = 0;
+
+       auto blif_wire = [&](const std::string &wire_name) -> Wire*
+       {
+               if (wire_name[0] == '$')
+               {
+                       for (int i = 0; i+1 < GetSize(wire_name); i++)
+                       {
+                               if (wire_name[i] != '$')
+                                       continue;
+
+                               int len = 0;
+                               while (i+len+1 < GetSize(wire_name) && '0' <= wire_name[i+len+1] && wire_name[i+len+1] <= '9')
+                                       len++;
+
+                               if (len > 0) {
+                                       string num_str = wire_name.substr(i+1, len);
+                                       int num = atoi(num_str.c_str()) & 0x0fffffff;
+                                       blif_maxnum = std::max(blif_maxnum, num);
+                               }
+                       }
+               }
+
+               IdString wire_id = RTLIL::escape_id(wire_name);
+               Wire *wire = module->wire(wire_id);
+
+               if (wire == nullptr)
+                       wire = module->addWire(wire_id);
+
+               return wire;
+       };
 
        dict<RTLIL::IdString, RTLIL::Const> *obj_attributes = nullptr;
        dict<RTLIL::IdString, RTLIL::Const> *obj_parameters = nullptr;
@@ -103,8 +134,41 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
                        if (module == nullptr)
                                goto error;
 
-                       if (!strcmp(cmd, ".end")) {
+                       if (!strcmp(cmd, ".end"))
+                       {
                                module->fixup_ports();
+
+                               if (run_clean)
+                               {
+                                       Const buffer_lut(vector<RTLIL::State>({State::S0, State::S1}));
+                                       vector<Cell*> remove_cells;
+
+                                       for (auto cell : module->cells())
+                                               if (cell->type == "$lut" && cell->getParam("\\LUT") == buffer_lut) {
+                                                       module->connect(cell->getPort("\\Y"), cell->getPort("\\A"));
+                                                       remove_cells.push_back(cell);
+                                               }
+
+                                       for (auto cell : remove_cells)
+                                               module->remove(cell);
+
+                                       Wire *true_wire = module->wire("$true");
+                                       Wire *false_wire = module->wire("$false");
+                                       Wire *undef_wire = module->wire("$undef");
+
+                                       if (true_wire != nullptr)
+                                               module->rename(true_wire, stringf("$true$%d", ++blif_maxnum));
+
+                                       if (false_wire != nullptr)
+                                               module->rename(false_wire, stringf("$false$%d", ++blif_maxnum));
+
+                                       if (undef_wire != nullptr)
+                                               module->rename(undef_wire, stringf("$undef$%d", ++blif_maxnum));
+
+                                       autoidx = std::max(autoidx, blif_maxnum+1);
+                                       blif_maxnum = 0;
+                               }
+
                                module = nullptr;
                                obj_attributes = nullptr;
                                obj_parameters = nullptr;
@@ -114,7 +178,10 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
                        if (!strcmp(cmd, ".inputs") || !strcmp(cmd, ".outputs")) {
                                char *p;
                                while ((p = strtok(NULL, " \t\r\n")) != NULL) {
-                                       RTLIL::Wire *wire = module->addWire(stringf("\\%s", p));
+                                       RTLIL::IdString wire_name(stringf("\\%s", p));
+                                       RTLIL::Wire *wire = module->wire(wire_name);
+                                       if (wire == nullptr)
+                                               wire = module->addWire(wire_name);
                                        if (!strcmp(cmd, ".inputs"))
                                                wire->port_input = true;
                                        else
@@ -162,37 +229,26 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
                                char *init = strtok(NULL, " \t\r\n");
                                RTLIL::Cell *cell = nullptr;
 
-                               if (module->wires_.count(RTLIL::escape_id(d)) == 0)
-                                       module->addWire(RTLIL::escape_id(d));
-
-                               if (module->wires_.count(RTLIL::escape_id(q)) == 0)
-                                       module->addWire(RTLIL::escape_id(q));
-
                                if (clock == nullptr && edge != nullptr) {
                                        init = edge;
                                        edge = nullptr;
                                }
 
                                if (init != nullptr && (init[0] == '0' || init[0] == '1'))
-                                       module->wire(RTLIL::escape_id(d))->attributes["\\init"] = Const(init[0] == '1' ? 1 : 0, 1);
+                                       blif_wire(d)->attributes["\\init"] = Const(init[0] == '1' ? 1 : 0, 1);
 
                                if (clock == nullptr)
                                        goto no_latch_clock;
 
-                               if (module->wires_.count(RTLIL::escape_id(clock)) == 0)
-                                       module->addWire(RTLIL::escape_id(clock));
-
                                if (!strcmp(edge, "re"))
-                                       cell = module->addDff(NEW_ID, module->wire(RTLIL::escape_id(clock)),
-                                                       module->wire(RTLIL::escape_id(d)), module->wire(RTLIL::escape_id(q)));
+                                       cell = module->addDff(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q));
                                else if (!strcmp(edge, "fe"))
-                                       cell = module->addDff(NEW_ID, module->wire(RTLIL::escape_id(clock)),
-                                                       module->wire(RTLIL::escape_id(d)), module->wire(RTLIL::escape_id(q)), false);
+                                       cell = module->addDff(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q), false);
                                else {
                        no_latch_clock:
                                        cell = module->addCell(NEW_ID, dff_name);
-                                       cell->setPort("\\D", module->wires_.at(RTLIL::escape_id(d)));
-                                       cell->setPort("\\Q", module->wires_.at(RTLIL::escape_id(q)));
+                                       cell->setPort("\\D", blif_wire(d));
+                                       cell->setPort("\\Q", blif_wire(q));
                                }
 
                                obj_attributes = &cell->attributes;
@@ -214,9 +270,7 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
                                        if (q == NULL || !q[0] || !q[1])
                                                goto error;
                                        *(q++) = 0;
-                                       if (module->wires_.count(RTLIL::escape_id(q)) == 0)
-                                               module->addWire(RTLIL::escape_id(q));
-                                       cell->setPort(RTLIL::escape_id(p), module->wires_.at(RTLIL::escape_id(q)));
+                                       cell->setPort(RTLIL::escape_id(p), blif_wire(q));
                                }
 
                                obj_attributes = &cell->attributes;
@@ -237,13 +291,7 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
                                if (q == NULL)
                                        goto error;
 
-                               if (module->wires_.count(RTLIL::escape_id(p)) == 0)
-                                       module->addWire(RTLIL::escape_id(p));
-
-                               if (module->wires_.count(RTLIL::escape_id(q)) == 0)
-                                       module->addWire(RTLIL::escape_id(q));
-
-                               module->connect(module->wires_.at(RTLIL::escape_id(q)), module->wires_.at(RTLIL::escape_id(p)));
+                               module->connect(blif_wire(q), blif_wire(p));
                                continue;
                        }
 
@@ -251,19 +299,13 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
                        {
                                char *p;
                                RTLIL::SigSpec input_sig, output_sig;
-                               while ((p = strtok(NULL, " \t\r\n")) != NULL) {
-                                       RTLIL::Wire *wire;
-                                       if (module->wires_.count(RTLIL::escape_id(p)) > 0) {
-                                               wire = module->wires_.at(RTLIL::escape_id(p));
-                                       } else {
-                                               wire = module->addWire(RTLIL::escape_id(p));
-                                       }
-                                       input_sig.append(wire);
-                               }
+                               while ((p = strtok(NULL, " \t\r\n")) != NULL)
+                                       input_sig.append(blif_wire(p));
                                output_sig = input_sig.extract(input_sig.size()-1, 1);
                                input_sig = input_sig.extract(0, input_sig.size()-1);
 
-                               if (input_sig.size() == 0) {
+                               if (input_sig.size() == 0)
+                               {
                                        RTLIL::State state = RTLIL::State::Sa;
                                        while (1) {
                                                if (!read_next_line(buffer, buffer_size, line_count, f))
@@ -288,9 +330,12 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name)
                                                        goto error;
                                                }
                                        }
+
                                finished_parsing_constval:
                                        if (state == RTLIL::State::Sa)
                                                state = RTLIL::State::S0;
+                                       if (output_sig.as_wire()->name == "$undef")
+                                               state = RTLIL::State::Sx;
                                        module->connect(RTLIL::SigSig(output_sig, state));
                                        goto continue_without_read;
                                }
@@ -367,7 +412,7 @@ struct BlifFrontend : public Frontend {
                }
                extra_args(f, filename, args, argidx);
 
-               parse_blif(design, *f, "\\DFF");
+               parse_blif(design, *f, "\\DFF", true);
        }
 } BlifFrontend;
 
index 4d7f59d6b2d52ead41e301de3dfcfcfbb275cede..3c01ed373d75d7eced14c6f6f57bc3ac24b01f0b 100644 (file)
@@ -24,7 +24,7 @@
 
 YOSYS_NAMESPACE_BEGIN
 
-extern void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name);
+extern void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name, bool run_clean = false);
 
 YOSYS_NAMESPACE_END