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proc_dlatch: Remove init values for combinatorial processes. 

Fixes #2258.
This commit is contained in:
Marcelina Kościelnicka 2020-07-12 15:38:51 +02:00
parent 240351c44e
commit b33744b03a
1 changed files with 33 additions and 0 deletions
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33
passes/proc/proc_dlatch.cc
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@ -37,6 +37,7 @@ struct proc_dlatch_db_t
dict<Cell*, vector<SigBit>> mux_srcbits;
dict<SigBit, pair<Cell*, int>> mux_drivers;
dict<SigBit, int> sigusers;
dict<SigBit, std::pair<State,SigBit>> initbits;
proc_dlatch_db_t(Module *module) : module(module), sigmap(module)
{
@ -69,9 +70,34 @@ struct proc_dlatch_db_t
}
for (auto wire : module->wires())
{
if (wire->port_input)
for (auto bit : sigmap(wire))
sigusers[bit]++;
if (wire->attributes.count(ID::init)) {
SigSpec wirebits = sigmap(wire);
Const initval = wire->attributes.at(ID::init);
for (int i = 0; i < GetSize(wirebits) && i < GetSize(initval); i++)
{
SigBit bit = wirebits[i];
State val = initval[i];
if (val != State::S0 && val != State::S1 && bit.wire != nullptr)
continue;
if (initbits.count(bit)) {
if (initbits.at(bit).first != val)
log_error("Conflicting init values for signal %s (%s = %s != %s).\n",
log_signal(bit), log_signal(SigBit(wire, i)),
log_signal(val), log_signal(initbits.at(bit).first));
continue;
}
initbits[bit] = std::make_pair(val,SigBit(wire,i));
}
}
}
}
bool quickcheck(const SigSpec &haystack, const SigSpec &needle)
@ -393,6 +419,13 @@ void proc_dlatch(proc_dlatch_db_t &db, RTLIL::Process *proc)
else
log("No latch inferred for signal `%s.%s' from process `%s.%s'.\n",
db.module->name.c_str(), log_signal(lhs), db.module->name.c_str(), proc->name.c_str());
for (auto &bit : lhs) {
auto it = db.initbits.find(bit);
if (it != db.initbits.end()) {
log("Removing init bit %s for non-memory siginal `%s.%s` in process `%s.%s`.\n", log_signal(it->second.first), db.module->name.c_str(), log_signal(bit), db.module->name.c_str(), proc->name.c_str());
it->second.second.wire->attributes.at(ID::init)[it->second.second.offset] = State::Sx;
}
}
db.module->connect(lhs, rhs);
offset += chunk.width;
}