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-rw-r--r--common/timing_opt.cc69
1 files changed, 53 insertions, 16 deletions
diff --git a/common/timing_opt.cc b/common/timing_opt.cc
index 3a289812..d1194876 100644
--- a/common/timing_opt.cc
+++ b/common/timing_opt.cc
@@ -80,7 +80,7 @@ class TimingOptimiser
bool optimise() {
log_info("Running timing-driven placement optimisation...\n");
#if 1
- timing_analysis(ctx, false, true, ctx->debug, false);
+ timing_analysis(ctx, false, true, false, false);
#endif
for (int i = 0; i < 20; i++) {
log_info(" Iteration %d...\n", i);
@@ -90,7 +90,7 @@ class TimingOptimiser
for (auto &path : crit_paths)
optimise_path(path);
#if 1
- timing_analysis(ctx, false, true, ctx->debug, false);
+ timing_analysis(ctx, false, true, false, false);
#endif
}
return true;
@@ -146,8 +146,17 @@ class TimingOptimiser
if (dstBel == BelId())
continue;
if (ctx->estimateDelay(ctx->getBelPinWire(cell->bel, port.first),
- ctx->getBelPinWire(dstBel, user.port)) > max_net_delay.at(std::make_pair(user.cell->name, user.port)))
+ ctx->getBelPinWire(dstBel, user.port)) > max_net_delay.at(std::make_pair(user.cell->name, user.port))) {
+#if 0
+ if (ctx->debug) {
+ log_info(" est delay %.02fns exceeded maximum %.02fns\n", ctx->getDelayNS(ctx->estimateDelay(ctx->getBelPinWire(cell->bel, port.first),
+ ctx->getBelPinWire(dstBel, user.port))),
+ ctx->getDelayNS(max_net_delay.at(std::make_pair(user.cell->name, user.port))));
+ }
+#endif
return false;
+
+ }
}
}
@@ -193,6 +202,7 @@ class TimingOptimiser
BelId curr = cell->bel;
Loc curr_loc = ctx->getBelLocation(curr);
int found_count = 0;
+ cell_neighbour_bels[cell->name] = std::unordered_set<BelId>{};
for (int dy = -d; dy <= d; dy++) {
for (int dx = -d; dx <= d; dx++) {
// Go through all the Bels at this location
@@ -207,7 +217,7 @@ class TimingOptimiser
CellInfo *bound = ctx->getBoundBelCell(bel);
if (bound == nullptr) {
free_bels_at_loc.push_back(bel);
- } else if (bound->belStrength <= STRENGTH_WEAK) {
+ } else if (bound->belStrength <= STRENGTH_WEAK || bound->constr_parent != nullptr || !bound->constr_children.empty()) {
bound_bels_at_loc.push_back(bel);
}
}
@@ -286,6 +296,7 @@ class TimingOptimiser
}
NPNR_ASSERT_FALSE("port user not found on net");
};
+ std::unordered_set<PortRef*> used_ports;
for (auto crit_net : crit_nets) {
std::deque<PortRef*> crit_path;
@@ -318,6 +329,8 @@ class TimingOptimiser
continue;
size_t user_idx = port_user_index(cell, port.second);
float usr_crit = net_crit.at(pn->name).criticality.at(user_idx);
+ if (used_ports.count(&(pn->users.at(user_idx))))
+ continue;
if (usr_crit >= max_crit) {
max_crit = usr_crit;
crit_sink = std::make_pair(pn, user_idx);
@@ -326,6 +339,7 @@ class TimingOptimiser
if (crit_sink.first != nullptr) {
crit_path.push_front(&(crit_sink.first->users.at(crit_sink.second)));
+ used_ports.insert(&(crit_sink.first->users.at(crit_sink.second)));
}
back_cursor = crit_sink.first;
}
@@ -350,14 +364,19 @@ class TimingOptimiser
if (tpclass != TMG_COMB_OUTPUT)
continue;
auto &crits = net_crit.at(pn->name).criticality;
- auto most_crit_usr = std::max_element(crits.begin(), crits.end());
- if (*most_crit_usr >= max_crit) {
- max_crit = *most_crit_usr;
- crit_sink = std::make_pair(pn, std::distance(crits.begin(), most_crit_usr));
+ for (size_t i = 0; i < crits.size(); i++) {
+ if (used_ports.count(&(pn->users.at(i))))
+ continue;
+ if (crits.at(i) >= max_crit) {
+ max_crit = crits.at(i);
+ crit_sink = std::make_pair(pn, i);
+ }
}
+
}
if (crit_sink.first != nullptr) {
fwd_cursor = &(crit_sink.first->users.at(crit_sink.second));
+ used_ports.insert(&(crit_sink.first->users.at(crit_sink.second)));
} else {
fwd_cursor = nullptr;
}
@@ -378,20 +397,30 @@ class TimingOptimiser
if (ctx->debug)
log_info("Optimising the following path: \n");
for (auto port : path) {
- if (ctx->debug)
- log_info(" %s.%s at %s\n", port->cell->name.c_str(ctx), port->port.c_str(ctx), ctx->getBelName(port->cell->bel).c_str(ctx));
+ if (ctx->debug) {
+ float crit = 0;
+ NetInfo *pn = port->cell->ports.at(port->port).net;
+ if (net_crit.count(pn->name) && !net_crit.at(pn->name).criticality.empty())
+ for (size_t i = 0; i < pn->users.size(); i++)
+ if (pn->users.at(i).cell == port->cell && pn->users.at(i).port == port->port)
+ crit = net_crit.at(pn->name).criticality.at(i);
+ log_info(" %s.%s at %s crit %0.02f\n", port->cell->name.c_str(ctx), port->port.c_str(ctx), ctx->getBelName(port->cell->bel).c_str(ctx), crit);
+
+ }
if (std::find(path_cells.begin(), path_cells.end(), port->cell->name) != path_cells.end())
continue;
- if (port->cell->belStrength > STRENGTH_WEAK || !cfg.cellTypes.count(port->cell->type))
+ if (port->cell->belStrength > STRENGTH_WEAK || !cfg.cellTypes.count(port->cell->type) || port->cell->constr_parent != nullptr || !port->cell->constr_children.empty())
continue;
if (ctx->debug)
log_info(" can move\n");
path_cells.push_back(port->cell->name);
}
- if (path_cells.empty())
+ if (path_cells.size() < 3) {
+ log_info("Too few moveable cells; skipping path\n");
+ log_break();
return;
-
+ }
IdString last_cell;
const int d = 3; // FIXME: how to best determine d
for (auto cell : path_cells) {
@@ -420,9 +449,17 @@ class TimingOptimiser
std::unordered_set<std::pair<int, BelId>> to_visit;
for (auto startbel : cell_neighbour_bels[path_cells.front()]) {
- auto entry = std::make_pair(0, startbel);
- visit.push(entry);
- cumul_costs[path_cells.front()][startbel] = 0;
+ // Swap for legality check
+ CellInfo *cell = ctx->cells.at(path_cells.front()).get();
+ BelId origBel = cell_swap_bel(cell, startbel);
+ std::vector<std::pair<CellInfo*,BelId>> move{std::make_pair(cell, origBel)};
+ if (acceptable_move(move)) {
+ auto entry = std::make_pair(0, startbel);
+ visit.push(entry);
+ cumul_costs[path_cells.front()][startbel] = 0;
+ }
+ // Swap back
+ cell_swap_bel(cell, origBel);
}
while(!visit.empty()) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-28 02:13:08 +0000