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Dispose of far too long routes earlier (use 3x est. delay as limit)

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Signed-off-by: Clifford Wolf <clifford@clifford.at>
This commit is contained in:
Clifford Wolf 2018-09-04 17:55:43 +02:00
parent e7fe046e57
commit e91241f10d
1 changed files with 21 additions and 12 deletions
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33
common/router1.cc
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@ -53,14 +53,15 @@ struct QueuedWire
WireId wire;
PipId pip;
delay_t delay = 0, togo = 0;
delay_t delay = 0, penalty = 0, togo = 0;
int randtag = 0;
struct Greater
{
bool operator()(const QueuedWire &lhs, const QueuedWire &rhs) const noexcept
{
delay_t l = lhs.delay + lhs.togo, r = rhs.delay + rhs.togo;
delay_t l = lhs.delay + lhs.penalty + lhs.togo;
delay_t r = rhs.delay + rhs.penalty + rhs.togo;
return l == r ? lhs.randtag > rhs.randtag : l > r;
}
};
@ -119,7 +120,7 @@ struct Router
delay_t maxDelay = 0.0;
WireId failedDest;
void route(const std::unordered_map<WireId, delay_t> &src_wires, WireId dst_wire)
void route(const std::unordered_map<WireId, delay_t> &src_wires, WireId dst_wire, delay_t max_delay)
{
std::priority_queue<QueuedWire, std::vector<QueuedWire>, QueuedWire::Greater> queue;
@ -129,7 +130,8 @@ struct Router
QueuedWire qw;
qw.wire = it.first;
qw.pip = PipId();
qw.delay = it.second - (it.second / 16);
qw.delay = it.second;
qw.penalty = -(it.second / 16);
if (cfg.useEstimate)
qw.togo = ctx->estimateDelay(qw.wire, dst_wire);
qw.randtag = ctx->rng();
@ -150,12 +152,16 @@ struct Router
for (auto pip : ctx->getPipsDownhill(qw.wire)) {
delay_t next_delay = qw.delay + ctx->getPipDelay(pip).maxDelay();
delay_t next_penalty = qw.penalty;
WireId next_wire = ctx->getPipDstWire(pip);
bool foundRipupNet = false;
thisVisitCnt++;
next_delay += ctx->getWireDelay(next_wire).maxDelay();
if (max_delay > 0 && next_delay > max_delay)
continue;
if (!ctx->checkWireAvail(next_wire)) {
if (!ripup)
continue;
@ -165,11 +171,11 @@ struct Router
auto it1 = scores.wireScores.find(next_wire);
if (it1 != scores.wireScores.end())
next_delay += (it1->second * ripup_penalty) / 8;
next_penalty += (it1->second * ripup_penalty) / 8;
auto it2 = scores.netWireScores.find(std::make_pair(ripupWireNet->name, next_wire));
if (it2 != scores.netWireScores.end())
next_delay += it2->second * ripup_penalty;
next_penalty += it2->second * ripup_penalty;
foundRipupNet = true;
}
@ -183,22 +189,23 @@ struct Router
auto it1 = scores.pipScores.find(pip);
if (it1 != scores.pipScores.end())
next_delay += (it1->second * ripup_penalty) / 8;
next_penalty += (it1->second * ripup_penalty) / 8;
auto it2 = scores.netPipScores.find(std::make_pair(ripupPipNet->name, pip));
if (it2 != scores.netPipScores.end())
next_delay += it2->second * ripup_penalty;
next_penalty += it2->second * ripup_penalty;
foundRipupNet = true;
}
if (foundRipupNet)
next_delay += ripup_penalty;
next_penalty += ripup_penalty;
NPNR_ASSERT(next_delay >= 0);
NPNR_ASSERT(next_delay + next_penalty >= 0);
if (visited.count(next_wire)) {
if (visited.at(next_wire).delay <= next_delay + ctx->getDelayEpsilon())
if (visited.at(next_wire).delay + visited.at(next_wire).penalty <= next_delay + next_penalty + ctx->getDelayEpsilon())
continue;
#if 0 // FIXME
if (ctx->debug)
@ -217,6 +224,7 @@ struct Router
next_qw.wire = next_wire;
next_qw.pip = pip;
next_qw.delay = next_delay;
next_qw.penalty = next_penalty;
if (cfg.useEstimate)
next_qw.togo = ctx->estimateDelay(next_wire, dst_wire);
next_qw.randtag = ctx->rng();
@ -235,7 +243,7 @@ struct Router
{
std::unordered_map<WireId, delay_t> src_wires;
src_wires[src_wire] = ctx->getWireDelay(src_wire).maxDelay();
route(src_wires, dst_wire);
route(src_wires, dst_wire, 0);
routedOkay = visited.count(dst_wire);
if (ctx->debug) {
@ -369,7 +377,8 @@ struct Router
log(" Path delay estimate: %.2f\n", float(ctx->estimateDelay(src_wire, dst_wire)));
}
route(src_wires, dst_wire);
delay_t max_delay = 3 * ctx->estimateDelay(src_wire, dst_wire);
route(src_wires, dst_wire, max_delay);
if (visited.count(dst_wire) == 0) {
if (ctx->debug)