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placer1: Optimise for performance

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Signed-off-by: David Shah <dave@ds0.me>
This commit is contained in:
David Shah 2018-12-13 13:15:12 +00:00
parent 0cb351df52
commit ade72de02f
1 changed files with 58 additions and 20 deletions
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78
common/placer1.cc
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@ -102,10 +102,28 @@ class SAPlacer
}
diameter = std::max(max_x, max_y) + 1;
net_bounds.resize(ctx->nets.size());
net_arc_tcost.resize(ctx->nets.size());
moveChange.already_bounds_changed.resize(ctx->nets.size());
moveChange.already_changed_arcs.resize(ctx->nets.size());
old_udata.reserve(ctx->nets.size());
net_by_udata.reserve(ctx->nets.size());
decltype(NetInfo::udata) n = 0;
for (auto &net : ctx->nets) {
old_udata.emplace_back(net.second->udata);
net_arc_tcost.at(n).resize(net.second->users.size());
moveChange.already_changed_arcs.at(n).resize(net.second->users.size());
net.second->udata = n++;
net_by_udata.push_back(net.second.get());
}
build_port_index();
}
~SAPlacer() {}
~SAPlacer() {
for (auto &net : ctx->nets)
net.second->udata = old_udata[net.second->udata];
}
bool place()
{
@ -651,10 +669,9 @@ swap_fail:
NetInfo *ni = net.second;
if (ignore_net(ni))
continue;
net_bounds[ni->name] = get_net_bounds(ni);
net_arc_tcost[ni->name].resize(ni->users.size());
net_bounds[ni->udata] = get_net_bounds(ni);
for (size_t i = 0; i < ni->users.size(); i++)
net_arc_tcost[ni->name][i] = get_timing_cost(ni, i);
net_arc_tcost[ni->udata][i] = get_timing_cost(ni, i);
}
}
@ -663,7 +680,7 @@ swap_fail:
{
wirelen_t cost = 0;
for (const auto &net : net_bounds)
cost += net.second.hpwl();
cost += net.hpwl();
return cost;
}
@ -672,7 +689,7 @@ swap_fail:
{
double cost = 0;
for (const auto &net : net_arc_tcost) {
for (auto arc_cost : net.second) {
for (auto arc_cost : net) {
cost += arc_cost;
}
}
@ -682,17 +699,24 @@ swap_fail:
// Cost-change-related data for a move
struct MoveChangeData
{
std::unordered_set<IdString> bounds_changed_nets;
std::unordered_set<std::pair<IdString, size_t>> changed_arcs;
std::vector<decltype(NetInfo::udata)> bounds_changed_nets;
std::vector<std::pair<decltype(NetInfo::udata), size_t>> changed_arcs;
std::unordered_map<IdString, BoundingBox> new_net_bounds;
std::unordered_map<std::pair<IdString, size_t>, double> new_arc_costs;
std::vector<bool> already_bounds_changed;
std::vector<std::vector<bool>> already_changed_arcs;
std::vector<std::pair<decltype(NetInfo::udata), BoundingBox>> new_net_bounds;
std::vector<std::pair<std::pair<decltype(NetInfo::udata), size_t>, double>> new_arc_costs;
wirelen_t wirelen_delta = 0;
double timing_delta = 0;
void reset()
{
for (auto bc : bounds_changed_nets)
already_bounds_changed[bc] = false;
for (const auto &tc : changed_arcs)
already_changed_arcs[tc.first][tc.second] = false;
bounds_changed_nets.clear();
changed_arcs.clear();
new_net_bounds.clear();
@ -714,20 +738,30 @@ swap_fail:
continue;
if (ignore_net(pn))
continue;
const BoundingBox &curr_bounds = net_bounds[pn->name];
const BoundingBox &curr_bounds = net_bounds[pn->udata];
// If the old location was at the edge of the bounds, or the new location exceeds the bounds,
// an update is needed
if (curr_bounds.touches_bounds(old_loc.x, old_loc.y) || !curr_bounds.is_inside_inc(curr_loc.x, curr_loc.y))
mc.bounds_changed_nets.insert(pn->name);
if (!mc.already_bounds_changed[pn->udata]) {
mc.bounds_changed_nets.push_back(pn->udata);
mc.already_bounds_changed[pn->udata] = true;
}
// Output ports - all arcs change timing
if (port.second.type == PORT_OUT) {
int cc;
TimingPortClass cls = ctx->getPortTimingClass(cell, port.first, cc);
if (cls != TMG_IGNORE)
for (size_t i = 0; i < pn->users.size(); i++)
mc.changed_arcs.insert(std::make_pair(pn->name, i));
if (!mc.already_changed_arcs[pn->udata][i]) {
mc.changed_arcs.emplace_back(std::make_pair(pn->udata, i));
mc.already_changed_arcs[pn->udata][i] = true;
}
} else if (port.second.type == PORT_IN) {
mc.changed_arcs.insert(std::make_pair(pn->name, fast_port_to_user.at(&port.second)));
auto usr = fast_port_to_user.at(&port.second);
if (!mc.already_changed_arcs[pn->udata][usr]) {
mc.changed_arcs.emplace_back(std::make_pair(pn->udata, usr));
mc.already_changed_arcs[pn->udata][usr] = true;
}
}
}
}
@ -736,16 +770,18 @@ swap_fail:
{
for (const auto &bc : md.bounds_changed_nets) {
wirelen_t old_hpwl = net_bounds.at(bc).hpwl();
auto bounds = get_net_bounds(ctx->nets.at(bc).get());
md.new_net_bounds[bc] = bounds;
auto bounds = get_net_bounds(net_by_udata.at(bc));
md.new_net_bounds.emplace_back(std::make_pair(bc, bounds));
md.wirelen_delta += (bounds.hpwl() - old_hpwl);
md.already_bounds_changed[bc] = false;
}
for (const auto &tc : md.changed_arcs) {
double old_cost = net_arc_tcost.at(tc.first).at(tc.second);
double new_cost = get_timing_cost(ctx->nets.at(tc.first).get(), tc.second);
md.new_arc_costs[tc] = new_cost;
double new_cost = get_timing_cost(net_by_udata.at(tc.first), tc.second);
md.new_arc_costs.emplace_back(std::make_pair(tc, new_cost));
md.timing_delta += (new_cost - old_cost);
md.already_changed_arcs[tc.first][tc.second] = false;
}
}
@ -774,9 +810,9 @@ swap_fail:
inline double curr_metric() { return lambda * curr_timing_cost + (1 - lambda) * curr_wirelen_cost; }
// Map nets to their bounding box (so we can skip recompute for moves that do not exceed the bounds
std::unordered_map<IdString, BoundingBox> net_bounds;
std::vector<BoundingBox> net_bounds;
// Map net arcs to their timing cost (criticality * delay ns)
std::unordered_map<IdString, std::vector<double>> net_arc_tcost;
std::vector<std::vector<double>> net_arc_tcost;
// Fast lookup for cell port to net user index
std::unordered_map<const PortInfo *, size_t> fast_port_to_user;
@ -798,6 +834,8 @@ swap_fail:
std::unordered_map<IdString, std::tuple<int, int>> bel_types;
std::vector<std::vector<std::vector<std::vector<BelId>>>> fast_bels;
std::unordered_set<BelId> locked_bels;
std::vector<NetInfo*> net_by_udata;
std::vector<decltype(NetInfo::udata)> old_udata;
bool require_legal = true;
const float legalise_temp = 0.001;
const float post_legalise_temp = 0.002;