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Minor refactoring of router infrastructure

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Signed-off-by: Clifford Wolf <clifford@clifford.at>
This commit is contained in:
Clifford Wolf 2018-06-20 13:32:50 +02:00
parent d5a032d00e
commit 3fda636e70
1 changed files with 102 additions and 78 deletions
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180
common/route.cc
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@ -61,14 +61,112 @@ void ripup_net(Context *ctx, IdString net_name)
struct Router
{
Context *ctx;
IdString net_name;
bool ripup;
delay_t ripup_penalty;
std::unordered_set<IdString> rippedNets;
std::unordered_map<WireId, QueuedWire> visited;
int visitCnt = 0, revisitCnt = 0;
bool routedOkay = false;
delay_t maxDelay = 0.0;
WireId failedDest;
void route(const std::unordered_map<WireId, delay_t> &src_wires,
WireId dst_wire)
{
std::priority_queue<QueuedWire, std::vector<QueuedWire>,
QueuedWire::Greater>
queue;
visited.clear();
for (auto &it : src_wires) {
QueuedWire qw;
qw.wire = it.first;
qw.pip = PipId();
qw.delay = it.second;
qw.togo = ctx->estimateDelay(qw.wire, dst_wire);
qw.randtag = ctx->rng();
queue.push(qw);
visited[qw.wire] = qw;
}
while (!queue.empty() && !visited.count(dst_wire)) {
QueuedWire qw = queue.top();
queue.pop();
for (auto pip : ctx->getPipsDownhill(qw.wire)) {
delay_t next_delay = qw.delay;
IdString ripupNet = net_name;
visitCnt++;
if (!ctx->checkPipAvail(pip)) {
if (!ripup)
continue;
ripupNet = ctx->getPipNet(pip, true);
if (ripupNet == net_name)
continue;
}
WireId next_wire = ctx->getPipDstWire(pip);
next_delay += ctx->getPipDelay(pip).avgDelay();
if (!ctx->checkWireAvail(next_wire)) {
if (!ripup)
continue;
ripupNet = ctx->getWireNet(next_wire, true);
if (ripupNet == net_name)
continue;
}
if (ripupNet != net_name)
next_delay += ripup_penalty;
assert(next_delay >= 0);
if (visited.count(next_wire)) {
if (visited.at(next_wire).delay <=
next_delay + ctx->getDelayEpsilon())
continue;
#if 0 // FIXME
if (ctx->verbose)
log("Found better route to %s. Old vs new delay "
"estimate: %.3f %.3f\n",
ctx->getWireName(next_wire).c_str(),
ctx->getDelayNS(visited.at(next_wire).delay),
ctx->getDelayNS(next_delay));
#endif
revisitCnt++;
}
QueuedWire next_qw;
next_qw.wire = next_wire;
next_qw.pip = pip;
next_qw.delay = next_delay;
next_qw.togo = ctx->estimateDelay(next_wire, dst_wire);
qw.randtag = ctx->rng();
visited[next_qw.wire] = next_qw;
queue.push(next_qw);
}
}
}
Router(Context *ctx, WireId src_wire, WireId dst_wire, bool ripup = false,
delay_t ripup_penalty = 0)
: ctx(ctx), ripup(ripup), ripup_penalty(ripup_penalty)
{
std::unordered_map<WireId, delay_t> src_wires;
src_wires[src_wire] = 0;
route(src_wires, dst_wire);
}
Router(Context *ctx, IdString net_name, bool ripup = false,
delay_t ripup_penalty = 0)
: ctx(ctx), net_name(net_name), ripup(ripup),
ripup_penalty(ripup_penalty)
{
auto net_info = ctx->nets.at(net_name);
@ -108,8 +206,8 @@ struct Router
if (ctx->verbose)
log(" Source wire: %s\n", ctx->getWireName(src_wire).c_str(ctx));
std::unordered_map<WireId, DelayInfo> src_wires;
src_wires[src_wire] = DelayInfo();
std::unordered_map<WireId, delay_t> src_wires;
src_wires[src_wire] = 0;
net_info->wires[src_wire] = PipId();
ctx->bindWire(src_wire, net_name);
@ -156,81 +254,7 @@ struct Router
float(ctx->estimateDelay(src_wire, dst_wire)));
}
std::unordered_map<WireId, QueuedWire> visited;
std::priority_queue<QueuedWire, std::vector<QueuedWire>,
QueuedWire::Greater>
queue;
for (auto &it : src_wires) {
QueuedWire qw;
qw.wire = it.first;
qw.pip = PipId();
qw.delay = it.second.avgDelay();
qw.togo = ctx->estimateDelay(qw.wire, dst_wire);
qw.randtag = ctx->rng();
queue.push(qw);
visited[qw.wire] = qw;
}
while (!queue.empty() && !visited.count(dst_wire)) {
QueuedWire qw = queue.top();
queue.pop();
for (auto pip : ctx->getPipsDownhill(qw.wire)) {
delay_t next_delay = qw.delay;
IdString ripupNet = net_name;
visitCnt++;
if (!ctx->checkPipAvail(pip)) {
if (!ripup)
continue;
ripupNet = ctx->getPipNet(pip, true);
if (ripupNet == net_name)
continue;
}
WireId next_wire = ctx->getPipDstWire(pip);
next_delay += ctx->getPipDelay(pip).avgDelay();
if (!ctx->checkWireAvail(next_wire)) {
if (!ripup)
continue;
ripupNet = ctx->getWireNet(next_wire, true);
if (ripupNet == net_name)
continue;
}
if (ripupNet != net_name)
next_delay += ripup_penalty;
assert(next_delay >= 0);
if (visited.count(next_wire)) {
if (visited.at(next_wire).delay <=
next_delay + ctx->getDelayEpsilon())
continue;
#if 0 // FIXME
if (ctx->verbose)
log("Found better route to %s. Old vs new delay "
"estimate: %.3f %.3f\n",
ctx->getWireName(next_wire).c_str(),
ctx->getDelayNS(visited.at(next_wire).delay),
ctx->getDelayNS(next_delay));
#endif
revisitCnt++;
}
QueuedWire next_qw;
next_qw.wire = next_wire;
next_qw.pip = pip;
next_qw.delay = next_delay;
next_qw.togo = ctx->estimateDelay(next_wire, dst_wire);
qw.randtag = ctx->rng();
visited[next_qw.wire] = next_qw;
queue.push(next_qw);
}
}
route(src_wires, dst_wire);
if (visited.count(dst_wire) == 0) {
if (ctx->verbose)
@ -287,7 +311,7 @@ struct Router
ctx->bindWire(cursor, net_name);
ctx->bindPip(visited[cursor].pip, net_name);
src_wires[cursor] = ctx->getPipDelay(visited[cursor].pip);
src_wires[cursor] = visited[cursor].delay;
cursor = ctx->getPipSrcWire(visited[cursor].pip);
}
}