nextpnr/common/route/router1.cc
2024-09-24 08:57:21 +02:00

1496 lines
53 KiB
C++

/*
* nextpnr -- Next Generation Place and Route
*
* Copyright (C) 2018 Claire Xenia Wolf <claire@yosyshq.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#include <chrono>
#include <cmath>
#include <queue>
#include "log.h"
#include "router1.h"
#include "scope_lock.h"
#include "timing.h"
namespace {
USING_NEXTPNR_NAMESPACE
struct arc_key
{
NetInfo *net_info;
// logical user cell port index
store_index<PortRef> user_idx;
// physical index into cell->bel pin mapping (usually 0)
unsigned phys_idx;
bool operator==(const arc_key &other) const
{
return (net_info == other.net_info) && (user_idx == other.user_idx) && (phys_idx == other.phys_idx);
}
bool operator<(const arc_key &other) const
{
return net_info == other.net_info
? (user_idx == other.user_idx ? phys_idx < other.phys_idx : user_idx < other.user_idx)
: net_info->name < other.net_info->name;
}
unsigned int hash() const
{
std::size_t seed = std::hash<NetInfo *>()(net_info);
seed ^= user_idx.hash() + 0x9e3779b9 + (seed << 6) + (seed >> 2);
seed ^= std::hash<int>()(phys_idx) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
return seed;
}
};
struct arc_entry
{
arc_key arc;
delay_t pri;
int randtag = 0;
struct Less
{
bool operator()(const arc_entry &lhs, const arc_entry &rhs) const noexcept
{
if (lhs.pri != rhs.pri)
return lhs.pri < rhs.pri;
return lhs.randtag < rhs.randtag;
}
};
};
struct QueuedWire
{
WireId wire;
PipId pip;
delay_t delay = 0, penalty = 0, bonus = 0, togo = 0;
int randtag = 0;
struct Greater
{
bool operator()(const QueuedWire &lhs, const QueuedWire &rhs) const noexcept
{
delay_t l = lhs.delay + lhs.penalty + lhs.togo;
delay_t r = rhs.delay + rhs.penalty + rhs.togo;
NPNR_ASSERT(l >= 0);
NPNR_ASSERT(r >= 0);
l -= lhs.bonus;
r -= rhs.bonus;
return l == r ? lhs.randtag > rhs.randtag : l > r;
}
};
};
struct Router1
{
Context *ctx;
const Router1Cfg &cfg;
std::priority_queue<arc_entry, std::vector<arc_entry>, arc_entry::Less> arc_queue;
dict<WireId, pool<arc_key>> wire_to_arcs;
dict<arc_key, pool<WireId>> arc_to_wires;
pool<arc_key> queued_arcs;
std::priority_queue<QueuedWire, std::vector<QueuedWire>, QueuedWire::Greater> queue;
dict<WireId, int> wireScores;
dict<NetInfo *, int, hash_ptr_ops> netScores;
int arcs_with_ripup = 0;
int arcs_without_ripup = 0;
bool ripup_flag;
TimingAnalyser tmg;
bool timing_driven = true;
Router1(Context *ctx, const Router1Cfg &cfg) : ctx(ctx), cfg(cfg), tmg(ctx)
{
timing_driven = ctx->setting<bool>("timing_driven");
tmg.setup_only = false;
tmg.with_clock_skew = true;
tmg.setup();
tmg.run();
}
void arc_queue_insert(const arc_key &arc, WireId src_wire, WireId dst_wire)
{
if (queued_arcs.count(arc))
return;
delay_t pri = (arc.net_info->constant_value == IdString())
? (ctx->estimateDelay(src_wire, dst_wire) *
(100 * tmg.get_criticality(CellPortKey(arc.net_info->users.at(arc.user_idx)))))
: 0;
arc_entry entry;
entry.arc = arc;
entry.pri = pri;
entry.randtag = ctx->rng();
#if 0
if (ctx->debug)
log("[arc_queue_insert] %s (%d) %s %s [%d %d]\n", ctx->nameOf(entry.arc.net_info), entry.arc.user_idx,
ctx->nameOfWire(src_wire), ctx->nameOfWire(dst_wire), (int)entry.pri, entry.randtag);
#endif
arc_queue.push(entry);
queued_arcs.insert(arc);
}
void arc_queue_insert(const arc_key &arc)
{
if (queued_arcs.count(arc))
return;
NetInfo *net_info = arc.net_info;
auto user_idx = arc.user_idx;
unsigned phys_idx = arc.phys_idx;
auto src_wire = ctx->getNetinfoSourceWire(net_info);
auto dst_wire = ctx->getNetinfoSinkWire(net_info, net_info->users[user_idx], phys_idx);
arc_queue_insert(arc, src_wire, dst_wire);
}
arc_key arc_queue_pop()
{
arc_entry entry = arc_queue.top();
#if 0
if (ctx->debug)
log("[arc_queue_pop] %s (%d) [%d %d]\n", ctx->nameOf(entry.arc.net_info), entry.arc.user_idx,
(int)entry.pri, entry.randtag);
#endif
arc_queue.pop();
queued_arcs.erase(entry.arc);
return entry.arc;
}
void ripup_net(NetInfo *net)
{
if (ctx->debug)
log(" ripup net %s\n", ctx->nameOf(net));
netScores[net]++;
std::vector<WireId> wires;
for (auto &it : net->wires)
wires.push_back(it.first);
ctx->sorted_shuffle(wires);
for (WireId w : wires) {
std::vector<arc_key> arcs;
for (auto &it : wire_to_arcs[w]) {
arc_to_wires[it].erase(w);
arcs.push_back(it);
}
wire_to_arcs[w].clear();
ctx->sorted_shuffle(arcs);
for (auto &it : arcs)
arc_queue_insert(it);
if (ctx->debug)
log(" unbind wire %s\n", ctx->nameOfWire(w));
ctx->unbindWire(w);
wireScores[w]++;
}
ripup_flag = true;
}
void ripup_wire(WireId wire, int extra_indent = 0)
{
if (ctx->debug)
log(" ripup wire %s\n", ctx->nameOfWire(wire));
WireId w = ctx->getConflictingWireWire(wire);
if (w == WireId()) {
NetInfo *n = ctx->getConflictingWireNet(wire);
if (n != nullptr)
ripup_net(n);
} else {
std::vector<arc_key> arcs;
for (auto &it : wire_to_arcs[w]) {
arc_to_wires[it].erase(w);
arcs.push_back(it);
}
wire_to_arcs[w].clear();
ctx->sorted_shuffle(arcs);
for (auto &it : arcs)
arc_queue_insert(it);
if (ctx->debug)
log(" unbind wire %s\n", ctx->nameOfWire(w));
ctx->unbindWire(w);
wireScores[w]++;
}
ripup_flag = true;
}
void ripup_pip(PipId pip)
{
if (ctx->debug)
log(" ripup pip %s\n", ctx->nameOfPip(pip));
WireId w = ctx->getConflictingPipWire(pip);
if (w == WireId()) {
NetInfo *n = ctx->getConflictingPipNet(pip);
if (n != nullptr)
ripup_net(n);
} else {
std::vector<arc_key> arcs;
for (auto &it : wire_to_arcs[w]) {
arc_to_wires[it].erase(w);
arcs.push_back(it);
}
wire_to_arcs[w].clear();
ctx->sorted_shuffle(arcs);
for (auto &it : arcs)
arc_queue_insert(it);
if (ctx->debug)
log(" unbind wire %s\n", ctx->nameOfWire(w));
ctx->unbindWire(w);
wireScores[w]++;
}
ripup_flag = true;
}
bool skip_net(NetInfo *net_info)
{
#ifdef ARCH_ECP5
// ECP5 global nets currently appear part-unrouted due to arch database limitations
// Don't touch them in the router
if (net_info->is_global)
return true;
#endif
if (net_info->driver.cell == nullptr && net_info->constant_value == IdString())
return true;
return false;
}
void check()
{
pool<arc_key> valid_arcs;
for (auto &net_it : ctx->nets) {
NetInfo *net_info = net_it.second.get();
pool<WireId> valid_wires_for_net;
if (skip_net(net_info))
continue;
#if 0
if (ctx->debug)
log("[check] net: %s\n", ctx->nameOf(net_info));
#endif
auto src_wire = ctx->getNetinfoSourceWire(net_info);
log_assert(src_wire != WireId());
for (auto user : net_info->users.enumerate()) {
unsigned phys_idx = 0;
for (auto dst_wire : ctx->getNetinfoSinkWires(net_info, user.value)) {
log_assert(dst_wire != WireId());
arc_key arc;
arc.net_info = net_info;
arc.user_idx = user.index;
arc.phys_idx = phys_idx++;
valid_arcs.insert(arc);
#if 0
if (ctx->debug)
log("[check] arc: %s %s\n", ctx->nameOfWire(src_wire), ctx->nameOfWire(dst_wire));
#endif
for (WireId wire : arc_to_wires[arc]) {
#if 0
if (ctx->debug)
log("[check] wire: %s\n", ctx->nameOfWire(wire));
#endif
valid_wires_for_net.insert(wire);
log_assert(wire_to_arcs[wire].count(arc));
log_assert(net_info->wires.count(wire));
}
}
}
for (auto &it : net_info->wires) {
WireId w = it.first;
log_assert(valid_wires_for_net.count(w));
}
}
for (auto &it : wire_to_arcs) {
for (auto &arc : it.second)
log_assert(valid_arcs.count(arc));
}
for (auto &it : arc_to_wires) {
log_assert(valid_arcs.count(it.first));
}
}
void setup()
{
dict<WireId, NetInfo *> src_to_net;
dict<WireId, arc_key> dst_to_arc;
std::vector<IdString> net_names;
for (auto &net_it : ctx->nets)
net_names.push_back(net_it.first);
ctx->sorted_shuffle(net_names);
for (IdString net_name : net_names) {
NetInfo *net_info = ctx->nets.at(net_name).get();
if (skip_net(net_info))
continue;
auto src_wire = ctx->getNetinfoSourceWire(net_info);
if (src_wire == WireId() && net_info->constant_value == IdString())
log_error("No wire found for port %s on source cell %s.\n", ctx->nameOf(net_info->driver.port),
ctx->nameOf(net_info->driver.cell));
if (src_to_net.count(src_wire))
log_error("Found two nets with same source wire %s: %s vs %s\n", ctx->nameOfWire(src_wire),
ctx->nameOf(net_info), ctx->nameOf(src_to_net.at(src_wire)));
if (dst_to_arc.count(src_wire))
log_error("Wire %s is used as source and sink in different nets: %s vs %s (%d)\n",
ctx->nameOfWire(src_wire), ctx->nameOf(net_info),
ctx->nameOf(dst_to_arc.at(src_wire).net_info), dst_to_arc.at(src_wire).user_idx.idx());
for (auto user : net_info->users.enumerate()) {
unsigned phys_idx = 0;
for (auto dst_wire : ctx->getNetinfoSinkWires(net_info, user.value)) {
arc_key arc;
arc.net_info = net_info;
arc.user_idx = user.index;
arc.phys_idx = phys_idx++;
if (dst_wire == WireId())
log_error("No wire found for port %s on destination cell %s.\n", ctx->nameOf(user.value.port),
ctx->nameOf(user.value.cell));
if (dst_to_arc.count(dst_wire)) {
if (dst_to_arc.at(dst_wire).net_info == net_info)
continue;
log_error("Found two arcs with same sink wire %s: %s (%d) vs %s (%d)\n",
ctx->nameOfWire(dst_wire), ctx->nameOf(net_info), user.index.idx(),
ctx->nameOf(dst_to_arc.at(dst_wire).net_info),
dst_to_arc.at(dst_wire).user_idx.idx());
}
if (src_to_net.count(dst_wire))
log_error("Wire %s is used as source and sink in different nets: %s vs %s (%d)\n",
ctx->nameOfWire(dst_wire), ctx->nameOf(src_to_net.at(dst_wire)),
ctx->nameOf(net_info), user.index.idx());
dst_to_arc[dst_wire] = arc;
if (net_info->wires.count(dst_wire) == 0) {
arc_queue_insert(arc, src_wire, dst_wire);
continue;
}
WireId cursor = dst_wire;
wire_to_arcs[cursor].insert(arc);
arc_to_wires[arc].insert(cursor);
while (src_wire != cursor && (net_info->constant_value == IdString() ||
ctx->getWireConstantValue(cursor) != net_info->constant_value)) {
auto it = net_info->wires.find(cursor);
if (it == net_info->wires.end()) {
arc_queue_insert(arc, src_wire, dst_wire);
break;
}
NPNR_ASSERT(it->second.pip != PipId());
cursor = ctx->getPipSrcWire(it->second.pip);
wire_to_arcs[cursor].insert(arc);
arc_to_wires[arc].insert(cursor);
}
}
// TODO: this matches the situation before supporting multiple cell->bel pins, but do we want to keep
// this invariant?
if (phys_idx == 0)
log_warning("No wires found for port %s on destination cell %s.\n", ctx->nameOf(user.value.port),
ctx->nameOf(user.value.cell));
}
src_to_net[src_wire] = net_info;
std::vector<WireId> unbind_wires;
for (auto &it : net_info->wires)
if (it.second.strength < STRENGTH_LOCKED && wire_to_arcs.count(it.first) == 0)
unbind_wires.push_back(it.first);
for (auto it : unbind_wires)
ctx->unbindWire(it);
}
}
bool route_arc(const arc_key &arc, bool ripup)
{
NetInfo *net_info = arc.net_info;
auto user_idx = arc.user_idx;
auto src_wire = ctx->getNetinfoSourceWire(net_info);
auto dst_wire = ctx->getNetinfoSinkWire(net_info, net_info->users[user_idx], arc.phys_idx);
ripup_flag = false;
float crit = tmg.get_criticality(CellPortKey(net_info->users.at(user_idx)));
if (ctx->debug) {
log("Routing arc %d on net %s (%d arcs total):\n", user_idx.idx(), ctx->nameOf(net_info),
int(net_info->users.capacity()));
log(" source ... %s\n", ctx->nameOfWire(src_wire));
log(" sink ..... %s\n", ctx->nameOfWire(dst_wire));
}
// unbind wires that are currently used exclusively by this arc
pool<WireId> old_arc_wires;
old_arc_wires.swap(arc_to_wires[arc]);
for (WireId wire : old_arc_wires) {
auto &arc_wires = wire_to_arcs.at(wire);
NPNR_ASSERT(arc_wires.count(arc));
arc_wires.erase(arc);
if (arc_wires.empty()) {
if (ctx->debug)
log(" unbind %s\n", ctx->nameOfWire(wire));
ctx->unbindWire(wire);
}
}
// special case
if (src_wire == dst_wire) {
NetInfo *bound = ctx->getBoundWireNet(src_wire);
if (bound != nullptr)
NPNR_ASSERT(bound == net_info);
else {
ctx->bindWire(src_wire, net_info, STRENGTH_WEAK);
}
arc_to_wires[arc].insert(src_wire);
wire_to_arcs[src_wire].insert(arc);
return true;
}
// reset wire queue
if (!queue.empty()) {
std::priority_queue<QueuedWire, std::vector<QueuedWire>, QueuedWire::Greater> new_queue;
queue.swap(new_queue);
}
dict<WireId, QueuedWire> visited;
// A* main loop
int visitCnt = 0;
int maxVisitCnt = INT_MAX;
delay_t best_est = 0;
delay_t best_score = -1;
{
QueuedWire qw;
qw.wire = src_wire;
qw.pip = PipId();
qw.delay = ctx->getWireDelay(qw.wire).maxDelay();
qw.penalty = 0;
qw.bonus = 0;
if (cfg.useEstimate) {
qw.togo = ctx->estimateDelay(qw.wire, dst_wire);
best_est = qw.delay + qw.togo;
}
qw.randtag = ctx->rng();
queue.push(qw);
visited[qw.wire] = qw;
}
while (visitCnt++ < maxVisitCnt && !queue.empty()) {
QueuedWire qw = queue.top();
queue.pop();
for (auto pip : ctx->getPipsDownhill(qw.wire)) {
delay_t next_delay = qw.delay + ctx->getPipDelay(pip).maxDelay();
delay_t next_penalty = qw.penalty;
delay_t next_bonus = qw.bonus;
delay_t penalty_delta = 0;
WireId next_wire = ctx->getPipDstWire(pip);
next_delay += ctx->getWireDelay(next_wire).maxDelay();
WireId conflictWireWire = WireId(), conflictPipWire = WireId();
NetInfo *conflictWireNet = nullptr, *conflictPipNet = nullptr;
if (net_info->wires.count(next_wire) && net_info->wires.at(next_wire).pip == pip) {
next_bonus += cfg.reuseBonus * (1.0 - crit);
} else {
if (!ctx->checkWireAvail(next_wire)) {
if (!ripup)
continue;
conflictWireWire = ctx->getConflictingWireWire(next_wire);
if (conflictWireWire == WireId()) {
conflictWireNet = ctx->getConflictingWireNet(next_wire);
if (conflictWireNet == nullptr)
continue;
else {
if (conflictWireNet->wires.count(next_wire) &&
conflictWireNet->wires.at(next_wire).strength > STRENGTH_STRONG)
continue;
}
} else {
NetInfo *conflicting = ctx->getBoundWireNet(conflictWireWire);
if (conflicting != nullptr) {
if (conflicting->wires.count(conflictWireWire) &&
conflicting->wires.at(conflictWireWire).strength > STRENGTH_STRONG)
continue;
}
}
}
if (!ctx->checkPipAvail(pip)) {
if (!ripup)
continue;
conflictPipWire = ctx->getConflictingPipWire(pip);
if (conflictPipWire == WireId()) {
conflictPipNet = ctx->getConflictingPipNet(pip);
if (conflictPipNet == nullptr)
continue;
else {
if (conflictPipNet->wires.count(next_wire) &&
conflictPipNet->wires.at(next_wire).strength > STRENGTH_STRONG)
continue;
}
} else {
NetInfo *conflicting = ctx->getBoundWireNet(conflictPipWire);
if (conflicting != nullptr) {
if (conflicting->wires.count(conflictPipWire) &&
conflicting->wires.at(conflictPipWire).strength > STRENGTH_STRONG)
continue;
}
}
}
if (conflictWireNet != nullptr && conflictPipWire != WireId() &&
conflictWireNet->wires.count(conflictPipWire))
conflictPipWire = WireId();
if (conflictPipNet != nullptr && conflictWireWire != WireId() &&
conflictPipNet->wires.count(conflictWireWire))
conflictWireWire = WireId();
if (conflictWireWire == conflictPipWire)
conflictWireWire = WireId();
if (conflictWireNet == conflictPipNet)
conflictWireNet = nullptr;
if (conflictWireWire != WireId()) {
auto scores_it = wireScores.find(conflictWireWire);
if (scores_it != wireScores.end())
penalty_delta += scores_it->second * cfg.wireRipupPenalty;
penalty_delta += cfg.wireRipupPenalty;
}
if (conflictPipWire != WireId()) {
auto scores_it = wireScores.find(conflictPipWire);
if (scores_it != wireScores.end())
penalty_delta += scores_it->second * cfg.wireRipupPenalty;
penalty_delta += cfg.wireRipupPenalty;
}
if (conflictWireNet != nullptr) {
auto scores_it = netScores.find(conflictWireNet);
if (scores_it != netScores.end())
penalty_delta += scores_it->second * cfg.netRipupPenalty;
penalty_delta += cfg.netRipupPenalty;
penalty_delta += conflictWireNet->wires.size() * cfg.wireRipupPenalty;
}
if (conflictPipNet != nullptr) {
auto scores_it = netScores.find(conflictPipNet);
if (scores_it != netScores.end())
penalty_delta += scores_it->second * cfg.netRipupPenalty;
penalty_delta += cfg.netRipupPenalty;
penalty_delta += conflictPipNet->wires.size() * cfg.wireRipupPenalty;
}
}
next_penalty += penalty_delta * (timing_driven ? std::max(0.05, (1.0 - crit)) : 1);
delay_t next_score = next_delay + next_penalty;
NPNR_ASSERT(next_score >= 0);
if ((best_score >= 0) && (next_score - next_bonus - cfg.estimatePrecision > best_score))
continue;
auto old_visited_it = visited.find(next_wire);
if (old_visited_it != visited.end()) {
delay_t old_delay = old_visited_it->second.delay;
delay_t old_score = old_delay + old_visited_it->second.penalty;
NPNR_ASSERT(old_score >= 0);
if (next_score + ctx->getDelayEpsilon() >= old_score)
continue;
#if 0
if (ctx->debug)
log("Found better route to %s. Old vs new delay estimate: %.3f (%.3f) %.3f (%.3f)\n",
ctx->nameOfWire(next_wire),
ctx->getDelayNS(old_score),
ctx->getDelayNS(old_visited_it->second.delay),
ctx->getDelayNS(next_score),
ctx->getDelayNS(next_delay));
#endif
}
QueuedWire next_qw;
next_qw.wire = next_wire;
next_qw.pip = pip;
next_qw.delay = next_delay;
next_qw.penalty = next_penalty;
next_qw.bonus = next_bonus;
if (cfg.useEstimate) {
next_qw.togo = ctx->estimateDelay(next_wire, dst_wire);
delay_t this_est = next_qw.delay + next_qw.togo;
if (this_est / 2 - cfg.estimatePrecision > best_est)
continue;
if (best_est > this_est)
best_est = this_est;
}
next_qw.randtag = ctx->rng();
#if 0
if (ctx->debug)
log("%s -> %s: %.3f (%.3f)\n",
ctx->nameOfWire(qw.wire),
ctx->nameOfWire(next_wire),
ctx->getDelayNS(next_score),
ctx->getDelayNS(next_delay));
#endif
visited[next_qw.wire] = next_qw;
queue.push(next_qw);
if (next_wire == dst_wire) {
maxVisitCnt = std::min(maxVisitCnt, 2 * visitCnt + (next_qw.penalty > 0 ? 100 : 0));
best_score = next_score - next_bonus;
}
}
}
if (ctx->debug)
log(" total number of visited nodes: %d\n", visitCnt);
if (visited.count(dst_wire) == 0) {
if (ctx->debug)
log(" no route found for this arc\n");
return false;
}
if (ctx->debug) {
log(" final route delay: %8.2f\n", ctx->getDelayNS(visited[dst_wire].delay));
log(" final route penalty: %8.2f\n", ctx->getDelayNS(visited[dst_wire].penalty));
log(" final route bonus: %8.2f\n", ctx->getDelayNS(visited[dst_wire].bonus));
}
// bind resulting route (and maybe unroute other nets)
pool<WireId> unassign_wires = arc_to_wires[arc];
WireId cursor = dst_wire;
delay_t accumulated_path_delay = 0;
delay_t last_path_delay_delta = 0;
while (1) {
auto pip = visited[cursor].pip;
if (ctx->debug) {
delay_t path_delay_delta = ctx->estimateDelay(cursor, dst_wire) - accumulated_path_delay;
log(" node %s (%+.2f %+.2f)\n", ctx->nameOfWire(cursor), ctx->getDelayNS(path_delay_delta),
ctx->getDelayNS(path_delay_delta - last_path_delay_delta));
last_path_delay_delta = path_delay_delta;
if (pip != PipId())
accumulated_path_delay += ctx->getPipDelay(pip).maxDelay();
accumulated_path_delay += ctx->getWireDelay(cursor).maxDelay();
}
if (pip == PipId())
NPNR_ASSERT(cursor == src_wire);
if (!net_info->wires.count(cursor) || net_info->wires.at(cursor).pip != pip) {
if (!ctx->checkWireAvail(cursor)) {
ripup_wire(cursor);
NPNR_ASSERT(ctx->checkWireAvail(cursor));
}
if (pip != PipId() && !ctx->checkPipAvail(pip)) {
ripup_pip(pip);
NPNR_ASSERT(ctx->checkPipAvail(pip));
}
if (pip == PipId()) {
if (ctx->debug)
log(" bind wire %s\n", ctx->nameOfWire(cursor));
ctx->bindWire(cursor, net_info, STRENGTH_WEAK);
} else {
if (ctx->debug)
log(" bind pip %s\n", ctx->nameOfPip(pip));
ctx->bindPip(pip, net_info, STRENGTH_WEAK);
}
}
wire_to_arcs[cursor].insert(arc);
arc_to_wires[arc].insert(cursor);
if (pip == PipId())
break;
cursor = ctx->getPipSrcWire(pip);
}
if (ripup_flag)
arcs_with_ripup++;
else
arcs_without_ripup++;
return true;
}
bool route_const_arc(const arc_key &arc, bool ripup)
{
NetInfo *net_info = arc.net_info;
auto user_idx = arc.user_idx;
auto dst_wire = ctx->getNetinfoSinkWire(net_info, net_info->users[user_idx], arc.phys_idx);
ripup_flag = false;
if (ctx->debug) {
log("Routing constant arc %d on net %s (%d arcs total):\n", user_idx.idx(), ctx->nameOf(net_info),
int(net_info->users.capacity()));
log(" value ... %s\n", ctx->nameOf(net_info->constant_value));
log(" sink ..... %s\n", ctx->nameOfWire(dst_wire));
}
// unbind wires that are currently used exclusively by this arc
pool<WireId> old_arc_wires;
old_arc_wires.swap(arc_to_wires[arc]);
for (WireId wire : old_arc_wires) {
auto &arc_wires = wire_to_arcs.at(wire);
NPNR_ASSERT(arc_wires.count(arc));
arc_wires.erase(arc);
if (arc_wires.empty()) {
if (ctx->debug)
log(" unbind %s\n", ctx->nameOfWire(wire));
ctx->unbindWire(wire);
}
}
// special case
if (ctx->getWireConstantValue(dst_wire) == net_info->constant_value) {
NetInfo *bound = ctx->getBoundWireNet(dst_wire);
if (bound != nullptr)
NPNR_ASSERT(bound == net_info);
else {
ctx->bindWire(dst_wire, net_info, STRENGTH_WEAK);
}
arc_to_wires[arc].insert(dst_wire);
wire_to_arcs[dst_wire].insert(arc);
return true;
}
// reset wire queue
if (!queue.empty()) {
std::priority_queue<QueuedWire, std::vector<QueuedWire>, QueuedWire::Greater> new_queue;
queue.swap(new_queue);
}
dict<WireId, QueuedWire> visited;
// A* main loop
int visitCnt = 0;
int maxVisitCnt = INT_MAX;
delay_t best_score = -1;
WireId best_src;
{
QueuedWire qw;
qw.wire = dst_wire;
qw.pip = PipId();
qw.delay = ctx->getWireDelay(qw.wire).maxDelay();
qw.penalty = 0;
qw.bonus = 0;
qw.randtag = ctx->rng();
queue.push(qw);
visited[qw.wire] = qw;
}
while (visitCnt++ < maxVisitCnt && !queue.empty()) {
QueuedWire qw = queue.top();
queue.pop();
for (auto pip : ctx->getPipsUphill(qw.wire)) {
delay_t next_delay = qw.delay + ctx->getPipDelay(pip).maxDelay();
delay_t next_penalty = qw.penalty;
delay_t next_bonus = qw.bonus;
delay_t penalty_delta = 0;
WireId next_wire = ctx->getPipSrcWire(pip);
next_delay += ctx->getWireDelay(next_wire).maxDelay();
WireId conflictWireWire = WireId(), conflictPipWire = WireId();
NetInfo *conflictWireNet = nullptr, *conflictPipNet = nullptr;
if (net_info->wires.count(qw.wire)) {
if (net_info->wires.at(qw.wire).pip != pip)
continue;
next_bonus += cfg.reuseBonus;
} else {
if (!ctx->checkWireAvail(next_wire)) {
if (!ripup)
continue;
conflictWireWire = ctx->getConflictingWireWire(next_wire);
if (conflictWireWire == WireId()) {
conflictWireNet = ctx->getConflictingWireNet(next_wire);
if (conflictWireNet == nullptr)
continue;
else {
if (conflictWireNet->wires.count(next_wire) &&
conflictWireNet->wires.at(next_wire).strength > STRENGTH_STRONG)
continue;
}
} else {
NetInfo *conflicting = ctx->getBoundWireNet(conflictWireWire);
if (conflicting != nullptr) {
if (conflicting->wires.count(conflictWireWire) &&
conflicting->wires.at(conflictWireWire).strength > STRENGTH_STRONG)
continue;
}
}
}
if (!ctx->checkPipAvail(pip)) {
if (!ripup)
continue;
conflictPipWire = ctx->getConflictingPipWire(pip);
if (conflictPipWire == WireId()) {
conflictPipNet = ctx->getConflictingPipNet(pip);
if (conflictPipNet == nullptr)
continue;
else {
if (conflictPipNet->wires.count(next_wire) &&
conflictPipNet->wires.at(next_wire).strength > STRENGTH_STRONG)
continue;
}
} else {
NetInfo *conflicting = ctx->getBoundWireNet(conflictPipWire);
if (conflicting != nullptr) {
if (conflicting->wires.count(conflictPipWire) &&
conflicting->wires.at(conflictPipWire).strength > STRENGTH_STRONG)
continue;
}
}
}
if (conflictWireNet != nullptr && conflictPipWire != WireId() &&
conflictWireNet->wires.count(conflictPipWire))
conflictPipWire = WireId();
if (conflictPipNet != nullptr && conflictWireWire != WireId() &&
conflictPipNet->wires.count(conflictWireWire))
conflictWireWire = WireId();
if (conflictWireWire == conflictPipWire)
conflictWireWire = WireId();
if (conflictWireNet == conflictPipNet)
conflictWireNet = nullptr;
if (conflictWireWire != WireId()) {
auto scores_it = wireScores.find(conflictWireWire);
if (scores_it != wireScores.end())
penalty_delta += scores_it->second * cfg.wireRipupPenalty;
penalty_delta += cfg.wireRipupPenalty;
}
if (conflictPipWire != WireId()) {
auto scores_it = wireScores.find(conflictPipWire);
if (scores_it != wireScores.end())
penalty_delta += scores_it->second * cfg.wireRipupPenalty;
penalty_delta += cfg.wireRipupPenalty;
}
if (conflictWireNet != nullptr) {
auto scores_it = netScores.find(conflictWireNet);
if (scores_it != netScores.end())
penalty_delta += scores_it->second * cfg.netRipupPenalty;
penalty_delta += cfg.netRipupPenalty;
penalty_delta += conflictWireNet->wires.size() * cfg.wireRipupPenalty;
}
if (conflictPipNet != nullptr) {
auto scores_it = netScores.find(conflictPipNet);
if (scores_it != netScores.end())
penalty_delta += scores_it->second * cfg.netRipupPenalty;
penalty_delta += cfg.netRipupPenalty;
penalty_delta += conflictPipNet->wires.size() * cfg.wireRipupPenalty;
}
}
next_penalty += penalty_delta;
delay_t next_score = next_delay + next_penalty;
NPNR_ASSERT(next_score >= 0);
if ((best_score >= 0) && (next_score - next_bonus - cfg.estimatePrecision > best_score))
continue;
auto old_visited_it = visited.find(next_wire);
if (old_visited_it != visited.end()) {
continue;
}
QueuedWire next_qw;
next_qw.wire = next_wire;
next_qw.pip = pip;
next_qw.delay = next_delay;
next_qw.penalty = next_penalty;
next_qw.bonus = next_bonus;
next_qw.randtag = ctx->rng();
visited[next_qw.wire] = next_qw;
queue.push(next_qw);
if (ctx->getWireConstantValue(next_wire) == net_info->constant_value) {
maxVisitCnt = std::min(maxVisitCnt, 2 * visitCnt + (next_qw.penalty > 0 ? 100 : 0));
if (best_src == WireId() || next_score < best_score) {
best_src = next_wire;
}
best_score = next_score - next_bonus;
}
}
}
if (ctx->debug)
log(" total number of visited nodes: %d\n", visitCnt);
if (best_src == WireId()) {
if (ctx->debug)
log(" no route found for this arc\n");
return false;
}
if (ctx->debug) {
log(" final route delay: %8.2f\n", ctx->getDelayNS(visited[dst_wire].delay));
log(" final route penalty: %8.2f\n", ctx->getDelayNS(visited[dst_wire].penalty));
log(" final route bonus: %8.2f\n", ctx->getDelayNS(visited[dst_wire].bonus));
}
// bind resulting route (and maybe unroute other nets)
pool<WireId> unassign_wires = arc_to_wires[arc];
WireId cursor = best_src;
if (!net_info->wires.count(cursor)) {
if (!ctx->checkWireAvail(cursor)) {
ripup_wire(cursor);
NPNR_ASSERT(ctx->checkWireAvail(cursor));
}
ctx->bindWire(cursor, net_info, STRENGTH_WEAK);
}
wire_to_arcs[cursor].insert(arc);
arc_to_wires[arc].insert(cursor);
while (1) {
auto pip = visited[cursor].pip;
if (pip == PipId()) {
NPNR_ASSERT(cursor == dst_wire);
break;
}
WireId next = ctx->getPipDstWire(pip);
if (!net_info->wires.count(next) || (net_info->wires.count(next) && net_info->wires.at(next).pip != pip)) {
if (!ctx->checkWireAvail(next)) {
ripup_wire(next);
NPNR_ASSERT(ctx->checkWireAvail(next));
}
if (!ctx->checkPipAvail(pip)) {
ripup_pip(pip);
NPNR_ASSERT(ctx->checkPipAvail(pip));
}
if (ctx->debug)
log(" bind pip %s\n", ctx->nameOfPip(pip));
ctx->bindPip(pip, net_info, STRENGTH_WEAK);
}
wire_to_arcs[next].insert(arc);
arc_to_wires[arc].insert(next);
cursor = next;
}
if (ripup_flag)
arcs_with_ripup++;
else
arcs_without_ripup++;
return true;
}
delay_t find_slack_thresh()
{
// If more than 5% of arcs have negative slack; use the 5% threshold as a ripup criteria
int arc_count = 0;
int failed_count = 0;
delay_t default_thresh = ctx->getDelayEpsilon();
for (auto &net : ctx->nets) {
NetInfo *ni = net.second.get();
if (skip_net(ni))
continue;
for (auto &usr : ni->users) {
++arc_count;
delay_t slack = tmg.get_setup_slack(CellPortKey(usr));
if (slack == std::numeric_limits<delay_t>::lowest())
continue;
if (slack < default_thresh)
++failed_count;
}
}
if (arc_count < 50 || (failed_count < (0.05 * arc_count))) {
return default_thresh;
}
std::vector<delay_t> slacks;
for (auto &net : ctx->nets) {
NetInfo *ni = net.second.get();
if (skip_net(ni))
continue;
for (auto &usr : ni->users) {
delay_t slack = tmg.get_setup_slack(CellPortKey(usr));
if (slack == std::numeric_limits<delay_t>::lowest())
continue;
slacks.push_back(slack);
}
}
std::sort(slacks.begin(), slacks.end());
delay_t thresh = slacks.at(int(slacks.size() * 0.05));
log_warning("%.f%% of arcs have failing slack; using %.2fns as ripup threshold. Consider a reduced Fmax "
"constraint.\n",
(100.0 * failed_count) / arc_count, ctx->getDelayNS(thresh));
return thresh;
}
};
} // namespace
NEXTPNR_NAMESPACE_BEGIN
Router1Cfg::Router1Cfg(Context *ctx)
{
maxIterCnt = ctx->setting<int>("router1/maxIterCnt", 200);
cleanupReroute = ctx->setting<bool>("router1/cleanupReroute", true);
fullCleanupReroute = ctx->setting<bool>("router1/fullCleanupReroute", true);
useEstimate = ctx->setting<bool>("router1/useEstimate", true);
wireRipupPenalty = ctx->getRipupDelayPenalty();
netRipupPenalty = 10 * ctx->getRipupDelayPenalty();
reuseBonus = wireRipupPenalty / 2;
estimatePrecision = 100 * ctx->getRipupDelayPenalty();
}
bool router1(Context *ctx, const Router1Cfg &cfg)
{
try {
log_break();
log_info("Routing..\n");
ScopeLock<Context> lock(ctx);
auto rstart = std::chrono::high_resolution_clock::now();
log_info("Setting up routing queue.\n");
Router1 router(ctx, cfg);
router.setup();
#ifndef NDEBUG
router.check();
#endif
log_info("Routing %d arcs.\n", int(router.arc_queue.size()));
int iter_cnt = 0;
int last_arcs_with_ripup = 0;
int last_arcs_without_ripup = 0;
int timing_fail_count = 0;
bool timing_ripup = ctx->setting<bool>("router/tmg_ripup", false);
delay_t ripup_slack = 0;
log_info(" | (re-)routed arcs | delta | remaining| time spent |\n");
log_info(" IterCnt | w/ripup wo/ripup | w/r wo/r | arcs| batch(sec) total(sec)|\n");
auto prev_time = rstart;
while (!router.arc_queue.empty()) {
if (++iter_cnt % 1000 == 0) {
auto curr_time = std::chrono::high_resolution_clock::now();
log_info("%10d | %8d %10d | %4d %5d | %9d| %10.02f %10.02f|\n", iter_cnt, router.arcs_with_ripup,
router.arcs_without_ripup, router.arcs_with_ripup - last_arcs_with_ripup,
router.arcs_without_ripup - last_arcs_without_ripup, int(router.arc_queue.size()),
std::chrono::duration<float>(curr_time - prev_time).count(),
std::chrono::duration<float>(curr_time - rstart).count());
prev_time = curr_time;
last_arcs_with_ripup = router.arcs_with_ripup;
last_arcs_without_ripup = router.arcs_without_ripup;
ctx->yield();
#ifndef NDEBUG
router.check();
#endif
}
if (ctx->debug)
log("-- %d --\n", iter_cnt);
arc_key arc = router.arc_queue_pop();
if (arc.net_info->constant_value != IdString()) {
if (!router.route_const_arc(arc, true)) {
log_warning("Failed to find a route for arc %d of net %s.\n", arc.user_idx.idx(),
ctx->nameOf(arc.net_info));
#ifndef NDEBUG
router.check();
ctx->check();
#endif
return false;
}
} else {
if (!router.route_arc(arc, true)) {
log_warning("Failed to find a route for arc %d of net %s.\n", arc.user_idx.idx(),
ctx->nameOf(arc.net_info));
#ifndef NDEBUG
router.check();
ctx->check();
#endif
return false;
}
}
// Timing driven ripup
if (timing_ripup && router.arc_queue.empty() && timing_fail_count < 50) {
++timing_fail_count;
router.tmg.run();
delay_t wns = 0, tns = 0;
if (timing_fail_count == 1)
ripup_slack = router.find_slack_thresh();
for (auto &net : ctx->nets) {
NetInfo *ni = net.second.get();
if (router.skip_net(ni))
continue;
bool is_locked = false;
for (auto &wire : ni->wires) {
if (wire.second.strength > STRENGTH_STRONG)
is_locked = true;
}
if (is_locked)
continue;
for (auto &usr : ni->users) {
delay_t slack = router.tmg.get_setup_slack(CellPortKey(usr));
if (slack == std::numeric_limits<delay_t>::lowest())
continue;
if (slack < 0) {
wns = std::min(wns, slack);
tns += slack;
}
if (slack <= ripup_slack) {
for (WireId w : ctx->getNetinfoSinkWires(ni, usr)) {
if (ctx->checkWireAvail(w))
continue;
router.ripup_wire(w);
}
}
}
}
log_info(" %d arcs ripped up due to negative slack WNS=%.02fns TNS=%.02fns.\n",
int(router.arc_queue.size()), ctx->getDelayNS(wns), ctx->getDelayNS(tns));
iter_cnt = 0;
router.wireScores.clear();
router.netScores.clear();
}
}
auto rend = std::chrono::high_resolution_clock::now();
log_info("%10d | %8d %10d | %4d %5d | %9d| %10.02f %10.02f|\n", iter_cnt, router.arcs_with_ripup,
router.arcs_without_ripup, router.arcs_with_ripup - last_arcs_with_ripup,
router.arcs_without_ripup - last_arcs_without_ripup, int(router.arc_queue.size()),
std::chrono::duration<float>(rend - prev_time).count(),
std::chrono::duration<float>(rend - rstart).count());
log_info("Routing complete.\n");
ctx->yield();
log_info("Router1 time %.02fs\n", std::chrono::duration<float>(rend - rstart).count());
#ifndef NDEBUG
router.check();
ctx->check();
log_assert(ctx->checkRoutedDesign());
#endif
log_info("Checksum: 0x%08x\n", ctx->checksum());
timing_analysis(ctx, true /* slack_histogram */, true /* print_fmax */, true /* print_path */,
true /* warn_on_failure */, true /* update_results */);
return true;
} catch (log_execution_error_exception) {
#ifndef NDEBUG
ctx->lock();
ctx->check();
ctx->unlock();
#endif
return false;
}
}
bool Context::checkRoutedDesign() const
{
const Context *ctx = getCtx();
for (auto &net_it : ctx->nets) {
NetInfo *net_info = net_it.second.get();
#ifdef ARCH_ECP5
if (net_info->is_global)
continue;
#endif
if (ctx->debug)
log("checking net %s\n", ctx->nameOf(net_info));
if (net_info->users.empty()) {
if (ctx->debug)
log(" net without sinks\n");
log_assert(net_info->wires.empty());
continue;
}
bool found_unrouted = false;
bool found_loop = false;
bool found_stub = false;
struct ExtraWireInfo
{
int order_num = 0;
pool<WireId> children;
};
dict<WireId, std::unique_ptr<ExtraWireInfo>> db;
for (auto &it : net_info->wires) {
WireId w = it.first;
PipId p = it.second.pip;
if (p != PipId()) {
log_assert(ctx->getPipDstWire(p) == w);
db.emplace(ctx->getPipSrcWire(p), std::make_unique<ExtraWireInfo>()).first->second->children.insert(w);
}
}
auto src_wire = ctx->getNetinfoSourceWire(net_info);
if (net_info->constant_value == IdString()) {
if (src_wire == WireId()) {
log_assert(net_info->driver.cell == nullptr);
if (ctx->debug)
log(" undriven and unrouted\n");
continue;
}
if (net_info->wires.count(src_wire) == 0) {
if (ctx->debug)
log(" source (%s) not bound to net\n", ctx->nameOfWire(src_wire));
found_unrouted = true;
}
}
dict<WireId, store_index<PortRef>> dest_wires;
for (auto user : net_info->users.enumerate()) {
for (auto dst_wire : ctx->getNetinfoSinkWires(net_info, user.value)) {
log_assert(dst_wire != WireId());
dest_wires[dst_wire] = user.index;
if (net_info->wires.count(dst_wire) == 0) {
if (ctx->debug)
log(" sink %d (%s) not bound to net\n", user.index.idx(), ctx->nameOfWire(dst_wire));
found_unrouted = true;
}
}
}
std::function<void(WireId, int)> setOrderNum;
pool<WireId> logged_wires;
setOrderNum = [&](WireId w, int num) {
auto &db_entry = *db.emplace(w, std::make_unique<ExtraWireInfo>()).first->second;
if (db_entry.order_num != 0) {
found_loop = true;
log(" %*s=> loop\n", 2 * num, "");
return;
}
db_entry.order_num = num;
for (WireId child : db_entry.children) {
if (ctx->debug) {
log(" %*s-> %s\n", 2 * num, "", ctx->nameOfWire(child));
logged_wires.insert(child);
}
setOrderNum(child, num + 1);
}
if (db_entry.children.empty()) {
if (dest_wires.count(w) != 0) {
if (ctx->debug)
log(" %*s=> sink %d\n", 2 * num, "", dest_wires.at(w).idx());
} else {
if (ctx->debug)
log(" %*s=> stub\n", 2 * num, "");
found_stub = true;
}
}
};
if (ctx->debug) {
log(" driver: %s\n", ctx->nameOfWire(src_wire));
logged_wires.insert(src_wire);
}
if (net_info->constant_value != IdString()) {
for (const auto &wire : net_info->wires) {
if (wire.second.pip == PipId() && ctx->getWireConstantValue(wire.first) == net_info->constant_value)
setOrderNum(wire.first, 1);
}
} else {
setOrderNum(src_wire, 1);
}
pool<WireId> dangling_wires;
for (auto &it : db) {
auto &db_entry = *it.second;
if (db_entry.order_num == 0)
dangling_wires.insert(it.first);
}
if (ctx->debug) {
if (dangling_wires.empty()) {
log(" no dangling wires.\n");
} else {
pool<WireId> root_wires = dangling_wires;
for (WireId w : dangling_wires) {
for (WireId c : db[w]->children)
root_wires.erase(c);
}
for (WireId w : root_wires) {
log(" dangling wire: %s\n", ctx->nameOfWire(w));
logged_wires.insert(w);
setOrderNum(w, 1);
}
for (WireId w : dangling_wires) {
if (logged_wires.count(w) == 0)
log(" loop: %s -> %s\n", ctx->nameOfWire(ctx->getPipSrcWire(net_info->wires.at(w).pip)),
ctx->nameOfWire(w));
}
}
}
bool fail = false;
if (found_unrouted) {
if (ctx->debug)
log("check failed: found unrouted arcs\n");
fail = true;
}
if (found_loop) {
if (ctx->debug)
log("check failed: found loops\n");
fail = true;
}
if (found_stub) {
if (ctx->debug)
log("check failed: found stubs\n");
fail = true;
}
if (!dangling_wires.empty()) {
if (ctx->debug)
log("check failed: found dangling wires\n");
fail = true;
}
if (fail)
return false;
}
return true;
}
bool Context::getActualRouteDelay(WireId src_wire, WireId dst_wire, delay_t *delay, dict<WireId, PipId> *route,
bool useEstimate)
{
// FIXME
return false;
}
NEXTPNR_NAMESPACE_END