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Added clk2fflogic support for $dffsr and $dlatch

This commit is contained in:
Clifford Wolf 2016-10-17 13:28:55 +02:00
parent 3a09d6bb65
commit 6425d34e73
1 changed files with 57 additions and 1 deletions
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58
passes/sat/clk2fflogic.cc
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@ -72,7 +72,47 @@ struct Clk2fflogicPass : public Pass {
for (auto cell : vector<Cell*>(module->selected_cells()))
{
if (cell->type.in("$dff", "$adff"))
if (cell->type.in("$dlatch"))
{
bool enpol = cell->parameters["\\EN_POLARITY"].as_bool();
SigSpec sig_en = cell->getPort("\\EN");
SigSpec sig_d = cell->getPort("\\D");
SigSpec sig_q = cell->getPort("\\Q");
log("Replacing %s.%s (%s): EN=%s, D=%s, Q=%s\n",
log_id(module), log_id(cell), log_id(cell->type),
log_signal(sig_en), log_signal(sig_d), log_signal(sig_q));
Wire *past_q = module->addWire(NEW_ID, GetSize(sig_q));
module->addFf(NEW_ID, sig_q, past_q);
if (enpol)
module->addMux(NEW_ID, past_q, sig_d, sig_en, sig_q);
else
module->addMux(NEW_ID, sig_d, past_q, sig_en, sig_q);
Const initval;
bool assign_initval = false;
for (int i = 0; i < GetSize(sig_d); i++) {
SigBit qbit = sigmap(sig_q[i]);
if (initbits.count(qbit)) {
initval.bits.push_back(initbits.at(qbit));
del_initbits.insert(qbit);
} else
initval.bits.push_back(State::Sx);
if (initval.bits.back() != State::Sx)
assign_initval = true;
}
if (assign_initval)
past_q->attributes["\\init"] = initval;
module->remove(cell);
continue;
}
if (cell->type.in("$dff", "$adff", "$dffsr"))
{
bool clkpol = cell->parameters["\\CLK_POLARITY"].as_bool();
@ -117,6 +157,22 @@ struct Clk2fflogicPass : public Pass {
module->addMux(NEW_ID, rstval, qval, arst, sig_q);
}
else
if (cell->type == "$dffsr")
{
SigSpec qval = module->Mux(NEW_ID, past_q, past_d, clock_edge);
SigSpec setval = cell->getPort("\\SET");
SigSpec clrval = cell->getPort("\\CLR");
if (!cell->parameters["\\SET_POLARITY"].as_bool())
setval = module->Not(NEW_ID, setval);
if (cell->parameters["\\CLR_POLARITY"].as_bool())
clrval = module->Not(NEW_ID, clrval);
qval = module->Or(NEW_ID, qval, setval);
module->addAnd(NEW_ID, qval, clrval, sig_q);
}
else
{
module->addMux(NEW_ID, past_q, past_d, clock_edge, sig_q);
}