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Fixed fsm_extract for wreduced muxes

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This commit is contained in:
Clifford Wolf 2014-08-08 13:47:20 +02:00
parent c07774b0b6
commit 7c94024fc3
1 changed files with 25 additions and 8 deletions
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33
passes/fsm/fsm_extract.cc
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@ -52,33 +52,50 @@ static bool find_states(RTLIL::SigSpec sig, const RTLIL::SigSpec &dff_out, RTLIL
std::set<sig2driver_entry_t> cellport_list;
sig2driver.find(sig, cellport_list);
for (auto &cellport : cellport_list) {
for (auto &cellport : cellport_list)
{
RTLIL::Cell *cell = module->cells_.at(cellport.first);
if ((cell->type != "$mux" && cell->type != "$pmux" && cell->type != "$safe_pmux") || cellport.second != "\\Y") {
log(" unexpected cell type %s (%s) found in state selection tree.\n", cell->type.c_str(), cell->name.c_str());
return false;
}
RTLIL::SigSpec sig_a = assign_map(cell->getPort("\\A"));
RTLIL::SigSpec sig_b = assign_map(cell->getPort("\\B"));
RTLIL::SigSpec sig_s = assign_map(cell->getPort("\\S"));
RTLIL::SigSpec sig_y = assign_map(cell->getPort("\\Y"));
RTLIL::SigSpec sig_aa = sig;
sig_aa.replace(sig_y, sig_a);
RTLIL::SigSpec sig_bb;
for (int i = 0; i < SIZE(sig_b)/SIZE(sig_a); i++) {
RTLIL::SigSpec s = sig;
s.replace(sig_y, sig_b.extract(i*SIZE(sig_a), SIZE(sig_a)));
sig_bb.append(s);
}
if (reset_state && RTLIL::SigSpec(*reset_state).is_fully_undef())
do {
if (sig_a.is_fully_def())
*reset_state = sig_a.as_const();
else if (sig_b.is_fully_def())
*reset_state = sig_b.as_const();
if (sig_aa.is_fully_def())
*reset_state = sig_aa.as_const();
else if (sig_bb.is_fully_def())
*reset_state = sig_bb.as_const();
else
break;
log(" found reset state: %s (guessed from mux tree)\n", log_signal(*reset_state));
} while (0);
if (ctrl.extract(sig_s).size() == 0) {
log(" found ctrl input: %s\n", log_signal(sig_s));
ctrl.append(sig_s);
}
if (!find_states(sig_a, dff_out, ctrl, states))
if (!find_states(sig_aa, dff_out, ctrl, states))
return false;
for (int i = 0; i < sig_b.size()/sig_a.size(); i++) {
if (!find_states(sig_b.extract(i*sig_a.size(), sig_a.size()), dff_out, ctrl, states))
for (int i = 0; i < SIZE(sig_bb)/SIZE(sig_aa); i++) {
if (!find_states(sig_bb.extract(i*SIZE(sig_aa), SIZE(sig_aa)), dff_out, ctrl, states))
return false;
}
}