From 5ff75b1cdce45fdc8422dbe2ac327217a5d2a2e6 Mon Sep 17 00:00:00 2001 From: Eddie Hung Date: Tue, 11 Jun 2019 15:48:20 -0700 Subject: [PATCH] Try way that doesn't involve creating a new wire --- passes/techmap/shregmap.cc | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/passes/techmap/shregmap.cc b/passes/techmap/shregmap.cc index 6c00d4d53..811b40eac 100644 --- a/passes/techmap/shregmap.cc +++ b/passes/techmap/shregmap.cc @@ -141,12 +141,8 @@ struct ShregmapWorker if (opts.init || sigbit_init.count(q_bit) == 0) { auto r = sigbit_chain_next.insert(std::make_pair(d_bit, cell)); - if (!r.second) { + if (!r.second) sigbit_with_non_chain_users.insert(d_bit); - Wire *wire = module->addWire(NEW_ID); - module->connect(wire, d_bit); - sigbit_chain_next.insert(std::make_pair(wire, cell)); - } sigbit_chain_prev[q_bit] = cell; continue; @@ -164,14 +160,14 @@ struct ShregmapWorker { for (auto it : sigbit_chain_next) { + Cell *c1, *c2 = it.second; + if (opts.tech == nullptr && sigbit_with_non_chain_users.count(it.first)) goto start_cell; - if (sigbit_chain_prev.count(it.first) != 0) + c1 = sigbit_chain_prev.at(it.first, nullptr); + if (c1 != nullptr) { - Cell *c1 = sigbit_chain_prev.at(it.first); - Cell *c2 = it.second; - if (c1->type != c2->type) goto start_cell; @@ -181,6 +177,15 @@ struct ShregmapWorker IdString d_port = opts.ffcells.at(c1->type).first; IdString q_port = opts.ffcells.at(c1->type).second; + // If the previous cell's D has other non chain users, + // then it is possible that this previous cell could + // be a start of the chain + SigBit d_bit = sigmap(c1->getPort(d_port).as_bit()); + if (sigbit_with_non_chain_users.count(d_bit)) { + c2 = c1; + goto start_cell; + } + auto c1_conn = c1->connections(); auto c2_conn = c1->connections(); @@ -197,7 +202,7 @@ struct ShregmapWorker } start_cell: - chain_start_cells.insert(it.second); + chain_start_cells.insert(c2); } }