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timing: Always use max delay for required time

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Signed-off-by: gatecat <gatecat@ds0.me>
This commit is contained in:
gatecat 2021-09-18 11:04:26 +01:00
parent 287a860283
commit 4730a4f339
1 changed files with 5 additions and 3 deletions
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8
common/timing.cc
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@ -427,15 +427,17 @@ void TimingAnalyser::walk_backward()
// Input port: propagate delay back through net, subtracting route delay
NetInfo *net = port_info(p).net;
if (net != nullptr && net->driver.cell != nullptr)
set_required_time(CellPortKey(net->driver), req.first, req.second.value - pd.route_delay,
req.second.path_length, p);
set_required_time(CellPortKey(net->driver), req.first,
req.second.value - DelayPair(pd.route_delay.maxDelay()), req.second.path_length,
p);
} else if (pd.type == PORT_OUT) {
// Output port : propagate delay back through cell, subtracting combinational delay
for (auto &fanin : pd.cell_arcs) {
if (fanin.type != CellArc::COMBINATIONAL)
continue;
set_required_time(CellPortKey(p.cell, fanin.other_port), req.first,
req.second.value - fanin.value.delayPair(), req.second.path_length + 1, p);
req.second.value - DelayPair(fanin.value.maxDelay()), req.second.path_length + 1,
p);
}
}
}