diff options
-rw-r--r-- | passes/memory/memory_dff.cc | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/passes/memory/memory_dff.cc b/passes/memory/memory_dff.cc index 220d29295..d37cac28e 100644 --- a/passes/memory/memory_dff.cc +++ b/passes/memory/memory_dff.cc @@ -182,20 +182,28 @@ struct MemoryDffWorker if (mux_cells_a.count(sig_data) || mux_cells_b.count(sig_data)) { - bool enable_invert = mux_cells_a.count(sig_data) != 0; - Cell *mux = enable_invert ? mux_cells_a.at(sig_data) : mux_cells_b.at(sig_data); - SigSpec check_q = sigmap(mux->getPort(enable_invert ? "\\B" : "\\A")); + RTLIL::SigSpec en; + RTLIL::SigSpec check_q; - sig_data = sigmap(mux->getPort("\\Y")); - for (auto bit : sig_data) - if (sigbit_users_count[bit] > 1) - goto skip_ff_after_read_merging; + do { + bool enable_invert = mux_cells_a.count(sig_data) != 0; + Cell *mux = enable_invert ? mux_cells_a.at(sig_data) : mux_cells_b.at(sig_data); + check_q = sigmap(mux->getPort(enable_invert ? "\\B" : "\\A")); + + sig_data = sigmap(mux->getPort("\\Y")); + for (auto bit : sig_data) + if (sigbit_users_count[bit] > 1) { + goto skip_ff_after_read_merging; + } + + en.append(enable_invert ? module->LogicNot(NEW_ID, mux->getPort("\\S")) : mux->getPort("\\S")); + } while (mux_cells_a.count(sig_data) || mux_cells_b.count(sig_data)); if (find_sig_before_dff(sig_data, clk_data, clk_polarity, true) && clk_data != RTLIL::SigSpec(RTLIL::State::Sx) && sig_data == check_q) { disconnect_dff(sig_data); cell->setPort("\\CLK", clk_data); - cell->setPort("\\EN", enable_invert ? module->LogicNot(NEW_ID, mux->getPort("\\S")) : mux->getPort("\\S")); + cell->setPort("\\EN", en.size() > 1 ? module->ReduceAnd(NEW_ID, en) : en); cell->setPort("\\DATA", sig_data); cell->parameters["\\CLK_ENABLE"] = RTLIL::Const(1); cell->parameters["\\CLK_POLARITY"] = RTLIL::Const(clk_polarity); |