flatten: make hygienic.
authorwhitequark <whitequark@whitequark.org>
Thu, 4 Jun 2020 10:13:48 +0000 (10:13 +0000)
committerwhitequark <whitequark@whitequark.org>
Mon, 8 Jun 2020 19:30:21 +0000 (19:30 +0000)
Before this commit, `flatten` matched the template objects with
the newly created objects solely by their name. Because of this,
it could be confused by code such as:

    module bar();
      $dff a();
    endmodule

    module foo();
      bar b();
      $dff \b.a ();
    endmodule

After this commit, `flatten` avoids every possible case of name
collision.

Fixes #2106.

passes/techmap/flatten.cc

index 027bb137d56527bb253b620ff14ef94200c69017..66915916790029787168aec26941c8f2b1252b36 100644 (file)
 USING_YOSYS_NAMESPACE
 PRIVATE_NAMESPACE_BEGIN
 
-void apply_prefix(IdString prefix, IdString &id)
+IdString concat_name(RTLIL::Cell *cell, IdString object_name)
 {
-       if (id[0] == '\\')
-               id = stringf("%s.%s", prefix.c_str(), id.c_str()+1);
+       if (object_name[0] == '\\')
+               return stringf("%s.%s", cell->name.c_str(), object_name.c_str() + 1);
        else
-               id = stringf("$flatten%s.%s", prefix.c_str(), id.c_str());
+               return stringf("$flatten%s.%s", cell->name.c_str(), object_name.c_str());
 }
 
-void apply_prefix(IdString prefix, RTLIL::SigSpec &sig, RTLIL::Module *module)
+template<class T>
+IdString map_name(RTLIL::Cell *cell, T *object)
+{
+       return cell->module->uniquify(concat_name(cell, object->name));
+}
+
+template<class T>
+void map_attributes(RTLIL::Cell *cell, T *object)
+{
+       if (object->attributes.count(ID::src))
+               object->add_strpool_attribute(ID::src, cell->get_strpool_attribute(ID::src));
+}
+
+void map_sigspec(const dict<RTLIL::Wire*, RTLIL::Wire*> &map, RTLIL::SigSpec &sig, RTLIL::Module *into = nullptr)
 {
        vector<SigChunk> chunks = sig;
        for (auto &chunk : chunks)
-               if (chunk.wire != nullptr) {
-                       IdString wire_name = chunk.wire->name;
-                       apply_prefix(prefix, wire_name);
-                       log_assert(module->wire(wire_name) != nullptr);
-                       chunk.wire = module->wire(wire_name);
-               }
+               if (chunk.wire != nullptr && chunk.wire->module != into)
+                       chunk.wire = map.at(chunk.wire);
        sig = chunks;
 }
 
@@ -63,183 +72,135 @@ struct FlattenWorker
                        log_error("Flattening yielded processes -> this is not supported.\n");
                }
 
-               pool<string> extra_src_attrs = cell->get_strpool_attribute(ID::src);
-
-               dict<IdString, IdString> memory_renames;
+               // Copy the contents of the flattened cell
 
-               for (auto &it : tpl->memories) {
-                       IdString m_name = it.first;
-                       apply_prefix(cell->name, m_name);
-                       RTLIL::Memory *m = module->addMemory(m_name, it.second);
-                       if (m->attributes.count(ID::src))
-                               m->add_strpool_attribute(ID::src, extra_src_attrs);
-                       memory_renames[it.first] = m->name;
-                       design->select(module, m);
+               dict<IdString, IdString> memory_map;
+               for (auto &tpl_memory_it : tpl->memories) {
+                       RTLIL::Memory *new_memory = module->addMemory(map_name(cell, tpl_memory_it.second), tpl_memory_it.second);
+                       map_attributes(cell, new_memory);
+                       memory_map[tpl_memory_it.first] = new_memory->name;
+                       design->select(module, new_memory);
                }
 
+               dict<RTLIL::Wire*, RTLIL::Wire*> wire_map;
                dict<IdString, IdString> positional_ports;
-               dict<Wire*, IdString> temp_renamed_wires;
-
-               for (auto tpl_w : tpl->wires())
-               {
-                       if (tpl_w->port_id > 0)
-                       {
-                               IdString posportname = stringf("$%d", tpl_w->port_id);
-                               positional_ports.emplace(posportname, tpl_w->name);
-                       }
-                       IdString w_name = tpl_w->name;
-                       apply_prefix(cell->name, w_name);
-                       RTLIL::Wire *w = module->wire(w_name);
-                       if (w != nullptr) {
-                               if (!w->get_bool_attribute(ID::hierconn)) {
-                                       temp_renamed_wires[w] = w->name;
-                                       module->rename(w, NEW_ID);
-                                       w = nullptr;
-                               } else {
-                                       w->attributes.erase(ID::hierconn);
-                                       if (GetSize(w) < GetSize(tpl_w)) {
-                                               log_warning("Widening signal %s.%s to match size of %s.%s (via %s.%s).\n", log_id(module), log_id(w),
-                                                               log_id(tpl), log_id(tpl_w), log_id(module), log_id(cell));
-                                               w->width = GetSize(tpl_w);
+               for (auto tpl_wire : tpl->wires()) {
+                       if (tpl_wire->port_id > 0)
+                               positional_ports.emplace(stringf("$%d", tpl_wire->port_id), tpl_wire->name);
+
+                       RTLIL::Wire *new_wire = nullptr;
+                       if (tpl_wire->name[0] == '\\') {
+                               RTLIL::Wire *hier_wire = module->wire(concat_name(cell, tpl_wire->name));
+                               if (hier_wire != nullptr && hier_wire->get_bool_attribute(ID::hierconn)) {
+                                       hier_wire->attributes.erase(ID::hierconn);
+                                       if (GetSize(hier_wire) < GetSize(tpl_wire)) {
+                                               log_warning("Widening signal %s.%s to match size of %s.%s (via %s.%s).\n",
+                                                       log_id(module), log_id(hier_wire), log_id(tpl), log_id(tpl_wire), log_id(module), log_id(cell));
+                                               hier_wire->width = GetSize(tpl_wire);
                                        }
+                                       new_wire = hier_wire;
                                }
                        }
-                       if (w == nullptr) {
-                               w = module->addWire(w_name, tpl_w);
-                               w->port_input = false;
-                               w->port_output = false;
-                               w->port_id = 0;
-                               if (w->attributes.count(ID::src))
-                                       w->add_strpool_attribute(ID::src, extra_src_attrs);
+                       if (new_wire == nullptr) {
+                               new_wire = module->addWire(map_name(cell, tpl_wire), tpl_wire);
+                               new_wire->port_input = new_wire->port_output = false;
+                               new_wire->port_id = false;
                        }
-                       design->select(module, w);
+
+                       map_attributes(cell, new_wire);
+                       wire_map[tpl_wire] = new_wire;
+                       design->select(module, new_wire);
                }
 
-               SigMap sigmap(module);
+               for (auto tpl_cell : tpl->cells()) {
+                       RTLIL::Cell *new_cell = module->addCell(map_name(cell, tpl_cell), tpl_cell);
+                       map_attributes(cell, new_cell);
+                       if (new_cell->type.in(ID($memrd), ID($memwr), ID($meminit))) {
+                               IdString memid = new_cell->getParam(ID::MEMID).decode_string();
+                               new_cell->setParam(ID::MEMID, Const(memory_map.at(memid).str()));
+                       } else if (new_cell->type == ID($mem)) {
+                               IdString memid = new_cell->getParam(ID::MEMID).decode_string();
+                               new_cell->setParam(ID::MEMID, Const(concat_name(cell, memid).str()));
+                       }
+                       auto rewriter = [&](RTLIL::SigSpec &sig) { map_sigspec(wire_map, sig); };
+                       new_cell->rewrite_sigspecs(rewriter);
+                       design->select(module, new_cell);
+                       new_cells.push_back(new_cell);
+               }
 
-               SigMap tpl_sigmap(tpl);
-               pool<SigBit> tpl_written_bits;
+               for (auto &tpl_conn_it : tpl->connections()) {
+                       RTLIL::SigSig new_conn = tpl_conn_it;
+                       map_sigspec(wire_map, new_conn.first);
+                       map_sigspec(wire_map, new_conn.second);
+                       module->connect(new_conn);
+               }
 
-               for (auto tpl_cell : tpl->cells())
-               for (auto &conn : tpl_cell->connections())
-                       if (tpl_cell->output(conn.first))
-                               for (auto bit : tpl_sigmap(conn.second))
-                                       tpl_written_bits.insert(bit);
-               for (auto &conn : tpl->connections())
-                       for (auto bit : tpl_sigmap(conn.first))
-                               tpl_written_bits.insert(bit);
+               // Attach port connections of the flattened cell
 
-               SigMap port_signal_map;
+               SigMap tpl_sigmap(tpl);
+               pool<SigBit> tpl_driven;
+               for (auto tpl_cell : tpl->cells())
+                       for (auto &tpl_conn : tpl_cell->connections())
+                               if (tpl_cell->output(tpl_conn.first))
+                                       for (auto bit : tpl_sigmap(tpl_conn.second))
+                                               tpl_driven.insert(bit);
+               for (auto &tpl_conn : tpl->connections())
+                       for (auto bit : tpl_sigmap(tpl_conn.first))
+                               tpl_driven.insert(bit);
 
-               for (auto &it : cell->connections())
+               SigMap sigmap(module);
+               for (auto &port_it : cell->connections())
                {
-                       IdString portname = it.first;
-                       if (positional_ports.count(portname) > 0)
-                               portname = positional_ports.at(portname);
-                       if (tpl->wire(portname) == nullptr || tpl->wire(portname)->port_id == 0) {
-                               if (portname.begins_with("$"))
-                                       log_error("Can't map port `%s' of cell `%s' to template `%s'!\n", portname.c_str(), cell->name.c_str(), tpl->name.c_str());
+                       IdString port_name = port_it.first;
+                       if (positional_ports.count(port_name) > 0)
+                               port_name = positional_ports.at(port_name);
+                       if (tpl->wire(port_name) == nullptr || tpl->wire(port_name)->port_id == 0) {
+                               if (port_name.begins_with("$"))
+                                       log_error("Can't map port `%s' of cell `%s' to template `%s'!\n",
+                                               port_name.c_str(), cell->name.c_str(), tpl->name.c_str());
                                continue;
                        }
 
-                       if (GetSize(it.second) == 0)
+                       if (GetSize(port_it.second) == 0)
                                continue;
 
-                       RTLIL::Wire *w = tpl->wire(portname);
-                       RTLIL::SigSig c;
-
-                       if (w->port_output && !w->port_input) {
-                               c.first = it.second;
-                               c.second = RTLIL::SigSpec(w);
-                               apply_prefix(cell->name, c.second, module);
-                       } else if (!w->port_output && w->port_input) {
-                               c.first = RTLIL::SigSpec(w);
-                               c.second = it.second;
-                               apply_prefix(cell->name, c.first, module);
+                       RTLIL::Wire *tpl_wire = tpl->wire(port_name);
+                       RTLIL::SigSig new_conn;
+                       if (tpl_wire->port_output && !tpl_wire->port_input) {
+                               new_conn.first = port_it.second;
+                               new_conn.second = tpl_wire;
+                       } else if (!tpl_wire->port_output && tpl_wire->port_input) {
+                               new_conn.first = tpl_wire;
+                               new_conn.second = port_it.second;
                        } else {
-                               SigSpec sig_tpl = w, sig_tpl_pf = w, sig_mod = it.second;
-                               apply_prefix(cell->name, sig_tpl_pf, module);
+                               SigSpec sig_tpl = tpl_wire, sig_mod = port_it.second;
                                for (int i = 0; i < GetSize(sig_tpl) && i < GetSize(sig_mod); i++) {
-                                       if (tpl_written_bits.count(tpl_sigmap(sig_tpl[i]))) {
-                                               c.first.append(sig_mod[i]);
-                                               c.second.append(sig_tpl_pf[i]);
+                                       if (tpl_driven.count(tpl_sigmap(sig_tpl[i]))) {
+                                               new_conn.first.append(sig_mod[i]);
+                                               new_conn.second.append(sig_tpl[i]);
                                        } else {
-                                               c.first.append(sig_tpl_pf[i]);
-                                               c.second.append(sig_mod[i]);
+                                               new_conn.first.append(sig_tpl[i]);
+                                               new_conn.second.append(sig_mod[i]);
                                        }
                                }
                        }
+                       map_sigspec(wire_map, new_conn.first, module);
+                       map_sigspec(wire_map, new_conn.second, module);
 
-                       if (c.second.size() > c.first.size())
-                               c.second.remove(c.first.size(), c.second.size() - c.first.size());
-
-                       if (c.second.size() < c.first.size())
-                               c.second.append(RTLIL::SigSpec(RTLIL::State::S0, c.first.size() - c.second.size()));
-
-                       log_assert(c.first.size() == c.second.size());
+                       if (new_conn.second.size() > new_conn.first.size())
+                               new_conn.second.remove(new_conn.first.size(), new_conn.second.size() - new_conn.first.size());
+                       if (new_conn.second.size() < new_conn.first.size())
+                               new_conn.second.append(RTLIL::SigSpec(RTLIL::State::S0, new_conn.first.size() - new_conn.second.size()));
+                       log_assert(new_conn.first.size() == new_conn.second.size());
 
-                       // connect internal and external wires
-
-                       if (sigmap(c.first).has_const())
+                       if (sigmap(new_conn.first).has_const())
                                log_error("Mismatch in directionality for cell port %s.%s.%s: %s <= %s\n",
-                                       log_id(module), log_id(cell), log_id(it.first), log_signal(c.first), log_signal(c.second));
+                                       log_id(module), log_id(cell), log_id(port_it.first), log_signal(new_conn.first), log_signal(new_conn.second));
 
-                       module->connect(c);
-               }
-
-               for (auto tpl_cell : tpl->cells())
-               {
-                       IdString c_name = tpl_cell->name;
-                       apply_prefix(cell->name, c_name);
-
-                       RTLIL::Cell *c = module->addCell(c_name, tpl_cell);
-                       new_cells.push_back(c);
-                       design->select(module, c);
-
-                       for (auto &conn : c->connections())
-                       {
-                               RTLIL::SigSpec new_conn = conn.second;
-                               apply_prefix(cell->name, new_conn, module);
-                               port_signal_map.apply(new_conn);
-                               c->setPort(conn.first, std::move(new_conn));
-                       }
-
-                       if (c->type.in(ID($memrd), ID($memwr), ID($meminit))) {
-                               IdString memid = c->getParam(ID::MEMID).decode_string();
-                               log_assert(memory_renames.count(memid) != 0);
-                               c->setParam(ID::MEMID, Const(memory_renames[memid].str()));
-                       }
-
-                       if (c->type == ID($mem)) {
-                               IdString memid = c->getParam(ID::MEMID).decode_string();
-                               apply_prefix(cell->name, memid);
-                               c->setParam(ID::MEMID, Const(memid.c_str()));
-                       }
-
-                       if (c->attributes.count(ID::src))
-                               c->add_strpool_attribute(ID::src, extra_src_attrs);
-               }
-
-               for (auto &it : tpl->connections()) {
-                       RTLIL::SigSig c = it;
-                       apply_prefix(cell->name.str(), c.first, module);
-                       apply_prefix(cell->name.str(), c.second, module);
-                       port_signal_map.apply(c.first);
-                       port_signal_map.apply(c.second);
-                       module->connect(c);
+                       module->connect(new_conn);
                }
 
                module->remove(cell);
-
-               for (auto &it : temp_renamed_wires)
-               {
-                       Wire *w = it.first;
-                       IdString name = it.second;
-                       IdString altname = module->uniquify(name);
-                       Wire *other_w = module->wire(name);
-                       module->rename(other_w, altname);
-                       module->rename(w, name);
-               }
        }
 
        void flatten_module(RTLIL::Design *design, RTLIL::Module *module, pool<RTLIL::Module*> &used_modules)