diff options
Diffstat (limited to 'passes/opt/opt_expr.cc')
| -rw-r--r-- | passes/opt/opt_expr.cc | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/passes/opt/opt_expr.cc b/passes/opt/opt_expr.cc index 512ef0cbf..acdc39937 100644 --- a/passes/opt/opt_expr.cc +++ b/passes/opt/opt_expr.cc @@ -641,6 +641,31 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons did_something = true; } } + + if (cell->type.in("$add", "$sub")) { + RTLIL::SigSpec sig_a = assign_map(cell->getPort("\\A")); + RTLIL::SigSpec sig_b = assign_map(cell->getPort("\\B")); + RTLIL::SigSpec sig_y = cell->getPort("\\Y"); + bool sub = cell->type == "$sub"; + + int i; + for (i = 0; i < GetSize(sig_y); i++) { + if (sig_b.at(i, State::Sx) == State::S0 && sig_a.at(i, State::Sx) != State::Sx) + module->connect(sig_y[i], sig_a[i]); + else if (!sub && sig_a.at(i, State::Sx) == State::S0 && sig_b.at(i, State::Sx) != State::Sx) + module->connect(sig_y[i], sig_b[i]); + else + break; + } + if (i > 0) { + cover_list("opt.opt_expr.fine", "$add", "$sub", cell->type.str()); + cell->setPort("\\A", sig_a.extract_end(i)); + cell->setPort("\\B", sig_b.extract_end(i)); + cell->setPort("\\Y", sig_y.extract_end(i)); + cell->fixup_parameters(); + did_something = true; + } + } } if (cell->type == "$reduce_xor" || cell->type == "$reduce_xnor" || cell->type == "$shift" || cell->type == "$shiftx" || |