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wip: cost of existing routing on heap

This commit is contained in:
gatecat 2026-08-15 11:01:41 +02:00
parent 9b117b8b95
commit 6710ec45aa
1 changed files with 33 additions and 14 deletions
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47
common/route/router2.cc
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@ -329,7 +329,7 @@ struct Router2
DeterministicRNG rng;
// Used to add existing routing to the heap
pool<WireId> in_wire_by_loc;
dict<WireId, float> wire_by_loc_cost;
dict<std::pair<int, int>, pool<WireId>> wire_by_loc;
};
@ -742,15 +742,34 @@ struct Router2
WireId cursor = ad.sink_wire;
if (!nd.wires.count(cursor))
return;
// Compute cost
float final_cost = 0;
while (cursor != nd.src_wire) {
if (!t.in_wire_by_loc.count(cursor)) {
t.in_wire_by_loc.insert(cursor);
for (auto dh : ctx->getPipsDownhill(cursor)) {
Loc dh_loc = ctx->getPipLocation(dh);
t.wire_by_loc[std::make_pair(dh_loc.x, dh_loc.y)].insert(cursor);
}
auto found = t.wire_by_loc_cost.find(cursor);
if (found != t.wire_by_loc_cost.end()) {
final_cost += found->second;
break;
}
cursor = ctx->getPipSrcWire(nd.wires.at(cursor).first);
auto pip = nd.wires.at(cursor).first;
final_cost += cfg.get_base_cost(ctx, cursor, pip, 0);
cursor = ctx->getPipSrcWire(pip);
}
while (cursor != nd.src_wire) {
if (t.wire_by_loc_cost.count(cursor))
break;
t.wire_by_loc_cost[cursor] = final_cost;
auto pip = nd.wires.at(cursor).first;
for (auto dh : ctx->getPipsDownhill(cursor)) {
Loc dh_loc = ctx->getPipLocation(dh);
t.wire_by_loc[std::make_pair(dh_loc.x, dh_loc.y)].insert(cursor);
}
// clamp at epsilon to avoid the risk of small negative delays breaking the router in case of rounding errors
final_cost = std::max(ctx->getDelayNS(ctx->getDelayEpsilon()),
final_cost - cfg.get_base_cost(ctx, cursor, pip, 0));
cursor = ctx->getPipSrcWire(pip);
}
}
@ -854,14 +873,14 @@ struct Router2
ROUTE_LOG_DBG("src_wire = %s -> dst_wire = %s\n", ctx->nameOfWire(src_wire), ctx->nameOfWire(dst_wire));
// Add 'forward' direction startpoints to queue
auto seed_queue_fwd = [&](WireId wire) {
auto seed_queue_fwd = [&](WireId wire, float base_cost = 0) {
WireScore base_score;
base_score.delay = 0;
base_score.cost = 0;
base_score.delay = base_cost;
base_score.cost = base_cost;
int wire_idx = wire_to_idx.at(wire);
base_score.togo_cost = get_togo_cost(net, i, wire_idx, dst_wire, false, crit_weight);
t.fwd_queue.push(QueuedWire(wire_idx, base_score));
set_visited_fwd(t, wire_idx, PipId(), 0.0);
set_visited_fwd(t, wire_idx, PipId(), base_cost);
};
auto &dst_data = flat_wires.at(dst_wire_idx);
// Look for nearby existing routing
@ -872,7 +891,7 @@ struct Router2
continue;
for (WireId wire : fnd->second) {
ROUTE_LOG_DBG(" seeding with %s\n", ctx->nameOfWire(wire));
seed_queue_fwd(wire);
seed_queue_fwd(wire, t.wire_by_loc_cost.at(wire));
}
}
@ -1176,7 +1195,7 @@ struct Router2
t.processed_sinks.clear();
t.route_arcs.clear();
t.wire_by_loc.clear();
t.in_wire_by_loc.clear();
t.wire_by_loc_cost.clear();
auto &nd = nets.at(net->udata);
bool failed_slack = false;
for (auto usr : net->users.enumerate())