From c863796e9ff91c76f0f8679b6871b8ffcb75edb6 Mon Sep 17 00:00:00 2001 From: Clifford Wolf Date: Tue, 26 Mar 2019 14:17:46 +0100 Subject: [PATCH] Fix "verific -extnets" for more complex situations Signed-off-by: Clifford Wolf --- frontends/verific/verific.cc | 86 +++++++++++++++++++++++++++++------- tests/sva/extnets.sv | 22 +++++++++ 2 files changed, 93 insertions(+), 15 deletions(-) create mode 100644 tests/sva/extnets.sv diff --git a/frontends/verific/verific.cc b/frontends/verific/verific.cc index c412cd3a3..95b7d3586 100644 --- a/frontends/verific/verific.cc +++ b/frontends/verific/verific.cc @@ -1619,30 +1619,35 @@ struct VerificExtNets int portname_cnt = 0; // a map from Net to the same Net one level up in the design hierarchy - std::map net_level_up; + std::map net_level_up_drive_up; + std::map net_level_up_drive_down; - Net *get_net_level_up(Net *net) + Net *route_up(Net *net, bool drive_up, Net *final_net = nullptr) { + auto &net_level_up = drive_up ? net_level_up_drive_up : net_level_up_drive_down; + if (net_level_up.count(net) == 0) { Netlist *nl = net->Owner(); // Simply return if Netlist is not unique - if (nl->NumOfRefs() != 1) - return net; + log_assert(nl->NumOfRefs() == 1); Instance *up_inst = (Instance*)nl->GetReferences()->GetLast(); Netlist *up_nl = up_inst->Owner(); // create new Port string name = stringf("___extnets_%d", portname_cnt++); - Port *new_port = new Port(name.c_str(), DIR_OUT); + Port *new_port = new Port(name.c_str(), drive_up ? DIR_OUT : DIR_IN); nl->Add(new_port); net->Connect(new_port); // create new Net in up Netlist - Net *new_net = new Net(name.c_str()); - up_nl->Add(new_net); + Net *new_net = final_net; + if (new_net == nullptr || new_net->Owner() != up_nl) { + new_net = new Net(name.c_str()); + up_nl->Add(new_net); + } up_inst->Connect(new_port, new_net); net_level_up[net] = new_net; @@ -1651,6 +1656,39 @@ struct VerificExtNets return net_level_up.at(net); } + Net *route_up(Net *net, bool drive_up, Netlist *dest, Net *final_net = nullptr) + { + while (net->Owner() != dest) + net = route_up(net, drive_up, final_net); + if (final_net != nullptr) + log_assert(net == final_net); + return net; + } + + Netlist *find_common_ancestor(Netlist *A, Netlist *B) + { + std::set ancestors_of_A; + + Netlist *cursor = A; + while (1) { + ancestors_of_A.insert(cursor); + if (cursor->NumOfRefs() != 1) + break; + cursor = ((Instance*)cursor->GetReferences()->GetLast())->Owner(); + } + + cursor = B; + while (1) { + if (ancestors_of_A.count(cursor)) + return cursor; + if (cursor->NumOfRefs() != 1) + break; + cursor = ((Instance*)cursor->GetReferences()->GetLast())->Owner(); + } + + log_error("No common ancestor found between %s and %s.\n", get_full_netlist_name(A).c_str(), get_full_netlist_name(B).c_str()); + } + void run(Netlist *nl) { MapIter mi, mi2; @@ -1674,19 +1712,37 @@ struct VerificExtNets if (verific_verbose) log("Fixing external net reference on port %s.%s.%s:\n", get_full_netlist_name(nl).c_str(), inst->Name(), port->Name()); - while (net->IsExternalTo(nl)) - { - Net *newnet = get_net_level_up(net); - if (newnet == net) break; + Netlist *ext_nl = net->Owner(); + if (verific_verbose) + log(" external net owner: %s\n", get_full_netlist_name(ext_nl).c_str()); + + Netlist *ca_nl = find_common_ancestor(nl, ext_nl); + + if (verific_verbose) + log(" common ancestor: %s\n", get_full_netlist_name(ca_nl).c_str()); + + Net *ca_net = route_up(net, !port->IsOutput(), ca_nl); + Net *new_net = ca_net; + + if (ca_nl != nl) + { if (verific_verbose) - log(" external net: %s.%s\n", get_full_netlist_name(net->Owner()).c_str(), net->Name()); - net = newnet; + log(" net in common ancestor: %s\n", ca_net->Name()); + + string name = stringf("___extnets_%d", portname_cnt++); + new_net = new Net(name.c_str()); + nl->Add(new_net); + + Net *n = route_up(new_net, port->IsOutput(), ca_nl, ca_net); + log_assert(n == ca_net); } if (verific_verbose) - log(" final net: %s.%s%s\n", get_full_netlist_name(net->Owner()).c_str(), net->Name(), net->IsExternalTo(nl) ? " (external)" : ""); - todo_connect.push_back(tuple(inst, port, net)); + log(" new local net: %s\n", new_net->Name()); + + log_assert(!new_net->IsExternalTo(nl)); + todo_connect.push_back(tuple(inst, port, new_net)); } for (auto it : todo_connect) { diff --git a/tests/sva/extnets.sv b/tests/sva/extnets.sv new file mode 100644 index 000000000..47312de7a --- /dev/null +++ b/tests/sva/extnets.sv @@ -0,0 +1,22 @@ +module top(input i, output o); + A A(); + B B(); + assign A.i = i; + assign o = B.o; + always @* assert(o == i); +endmodule + +module A; + wire i, y; +`ifdef FAIL + assign B.x = i; +`else + assign B.x = !i; +`endif + assign y = !B.y; +endmodule + +module B; + wire x, y, o; + assign y = x, o = A.y; +endmodule -- 2.30.2