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Added "dff2dffe -unmap"

This commit is contained in:
Clifford Wolf 2014-12-24 11:09:01 +01:00
parent afcacd6437
commit 8c1a72c2a4
1 changed files with 42 additions and 6 deletions
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48
passes/techmap/dff2dffe.cc
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@ -241,25 +241,61 @@ struct Dff2dffePass : public Pass {
log(" dff2dffe [selection]\n");
log("\n");
log("This pass transforms $dff cells driven by a tree of multiplexers with one or\n");
log("more feedback paths to $dffe cells.\n");
log("more feedback paths to $dffe cells. It also works on gate-level cells such as\n");
log("$_DFF_P_, $_DFF_N_ and $_MUX_.\n");
log("\n");
log(" -unmap\n");
log(" operate in the opposite direction: replace $dffe cells with combinations\n");
log(" of $dff and $mux cells\n");
log("\n");
}
virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
{
log_header("Executing DFF2DFFE pass (transform $dff to $dffe where applicable).\n");
bool unmap_mode = false;
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) {
// if (args[argidx] == "-foobar") {
// foobar_mode = true;
// continue;
// }
if (args[argidx] == "-unmap") {
unmap_mode = true;
continue;
}
break;
}
extra_args(args, argidx, design);
for (auto mod : design->selected_modules())
if (!mod->has_processes_warn()) {
if (!mod->has_processes_warn())
{
if (unmap_mode) {
for (auto cell : mod->selected_cells()) {
if (cell->type == "$dffe") {
RTLIL::SigSpec tmp = mod->addWire(NEW_ID, GetSize(cell->getPort("\\D")));
mod->addDff(NEW_ID, cell->getPort("\\CLK"), tmp, cell->getPort("\\Q"), cell->getParam("\\CLK_POLARITY").as_bool());
if (cell->getParam("\\EN_POLARITY").as_bool())
mod->addMux(NEW_ID, cell->getPort("\\Q"), cell->getPort("\\D"), cell->getPort("\\EN"), tmp);
else
mod->addMux(NEW_ID, cell->getPort("\\D"), cell->getPort("\\Q"), cell->getPort("\\EN"), tmp);
mod->remove(cell);
continue;
}
if (cell->type.substr(0, 7) == "$_DFFE_") {
bool clk_pol = cell->type.substr(7, 1) == "P";
bool en_pol = cell->type.substr(8, 1) == "P";
RTLIL::SigSpec tmp = mod->addWire(NEW_ID);
mod->addDff(NEW_ID, cell->getPort("\\C"), tmp, cell->getPort("\\Q"), clk_pol);
if (en_pol)
mod->addMux(NEW_ID, cell->getPort("\\Q"), cell->getPort("\\D"), cell->getPort("\\E"), tmp);
else
mod->addMux(NEW_ID, cell->getPort("\\D"), cell->getPort("\\Q"), cell->getPort("\\E"), tmp);
mod->remove(cell);
continue;
}
}
continue;
}
Dff2dffeWorker worker(mod);
worker.run();
}