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Fixes and improvements in new router

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Signed-off-by: Clifford Wolf <clifford@clifford.at>
This commit is contained in:
Clifford Wolf 2018-11-09 22:39:39 +01:00
parent aeaa0552ba
commit f0a3a272ca
2 changed files with 57 additions and 16 deletions
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69
common/router1.cc
View File

@ -67,7 +67,7 @@ struct QueuedWire
WireId wire;
PipId pip;
delay_t delay = 0, penalty = 0, togo = 0;
delay_t delay = 0, penalty = 0, bonus = 0, togo = 0;
int randtag = 0;
struct Greater
@ -76,6 +76,10 @@ struct QueuedWire
{
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;
}
};
@ -304,6 +308,7 @@ struct Router1
int visitCnt = 0;
int maxVisitCnt = INT_MAX;
delay_t best_est = 0;
delay_t best_score = -1;
{
QueuedWire qw;
@ -311,6 +316,7 @@ struct Router1
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;
@ -329,6 +335,7 @@ struct Router1
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;
WireId next_wire = ctx->getPipDstWire(pip);
next_delay += ctx->getWireDelay(next_wire).maxDelay();
@ -340,7 +347,7 @@ struct Router1
continue;
if (ripupWireNet == net_info) {
next_penalty += cfg.wireReusePenalty;
next_bonus += cfg.wireReuseBonus;
} else {
if (!ripup)
continue;
@ -348,6 +355,8 @@ struct Router1
auto scores_it = wireScores.find(next_wire);
if (scores_it != wireScores.end())
next_penalty += scores_it->second * cfg.wireRipupPenalty;
else
next_penalty += cfg.wireRipupPenalty;
}
}
@ -358,7 +367,7 @@ struct Router1
continue;
if (ripupPipNet == net_info) {
next_penalty += cfg.pipReusePenalty;
next_bonus += cfg.pipReuseBonus;
} else {
if (!ripup)
continue;
@ -366,17 +375,36 @@ struct Router1
auto scores_it = pipScores.find(pip);
if (scores_it != pipScores.end())
next_penalty += scores_it->second * cfg.pipRipupPenalty;
else
next_penalty += cfg.pipRipupPenalty;
}
}
if (visited.count(next_wire)) {
if (visited.at(next_wire).delay + visited.at(next_wire).penalty <= next_delay + next_penalty + ctx->getDelayEpsilon())
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 // FIXME
if (next_delay + ctx->getDelayEpsilon() >= old_delay)
continue;
#if 0
if (ctx->debug)
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),
log("Found better route to %s. Old vs new delay estimate: %.3f (%.3f) %.3f (%.3f)\n",
ctx->getWireName(next_wire).c_str(ctx),
ctx->getDelayNS(old_score),
ctx->getDelayNS(old_visited_it->second.delay),
ctx->getDelayNS(next_score),
ctx->getDelayNS(next_delay));
#endif
}
@ -386,21 +414,34 @@ struct Router1
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 > best_est + cfg.estimatePrecision)
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->getWireName(qw.wire).c_str(ctx),
ctx->getWireName(next_wire).c_str(ctx),
ctx->getDelayNS(next_score),
ctx->getDelayNS(next_delay));
#endif
visited[next_qw.wire] = next_qw;
queue.push(next_qw);
if (maxVisitCnt == INT_MAX && next_wire == dst_wire)
maxVisitCnt = 2*visitCnt;
if (next_wire == dst_wire) {
if (maxVisitCnt == INT_MAX)
maxVisitCnt = 2*visitCnt;
best_score = next_score - next_bonus;
}
}
}
@ -478,8 +519,8 @@ Router1Cfg::Router1Cfg(Context *ctx) : Settings(ctx)
wireRipupPenalty = ctx->getRipupDelayPenalty();
pipRipupPenalty = ctx->getRipupDelayPenalty();
wireReusePenalty = -wireRipupPenalty/8;
pipReusePenalty = -pipRipupPenalty/8;
wireReuseBonus = wireRipupPenalty/8;
pipReuseBonus = pipRipupPenalty/8;
estimatePrecision = 100 * ctx->getRipupDelayPenalty();
}

4
common/router1.h
View File

@ -35,8 +35,8 @@ struct Router1Cfg : Settings
bool useEstimate;
delay_t wireRipupPenalty;
delay_t pipRipupPenalty;
delay_t wireReusePenalty;
delay_t pipReusePenalty;
delay_t wireReuseBonus;
delay_t pipReuseBonus;
delay_t estimatePrecision;
};