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Add distance moved metrics, changing heuristics

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Signed-off-by: David Shah <davey1576@gmail.com>
This commit is contained in:
David Shah 2018-08-03 18:14:09 +02:00
parent aa8435df21
commit 4a751d9aaf
2 changed files with 31 additions and 1 deletions
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30
common/place_common.cc
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@ -425,6 +425,34 @@ class ConstraintLegaliseWorker
print_chain(child, depth + 1);
}
void print_stats(const char *point)
{
float distance_sum = 0;
float max_distance = 0;
int moved_cells = 0;
int unplaced_cells = 0;
for (auto orig : oldLocations) {
if (ctx->cells.at(orig.first)->bel == BelId()) {
unplaced_cells++;
continue;
}
Loc newLoc = ctx->getBelLocation(ctx->cells.at(orig.first)->bel);
if (newLoc != orig.second) {
float distance = std::sqrt(std::pow(newLoc.x - orig.second.x, 2) + pow(newLoc.y - orig.second.y, 2));
moved_cells++;
distance_sum += distance;
if (distance > max_distance)
max_distance = distance;
}
}
log_info(" moved %d cells, %d unplaced (after %s)\n", moved_cells, unplaced_cells, point);
if (moved_cells > 0) {
log_info(" average distance %f\n", (distance_sum / moved_cells));
log_info(" maximum distance %f\n", max_distance);
}
}
bool legalise_constraints()
{
log_info("Legalising relative constraints...\n");
@ -440,6 +468,7 @@ class ConstraintLegaliseWorker
return false;
}
}
print_stats("after legalising chains");
for (auto rippedCell : rippedCells) {
bool res = place_single_cell(ctx, ctx->cells.at(rippedCell).get(), true);
if (!res) {
@ -448,6 +477,7 @@ class ConstraintLegaliseWorker
return false;
}
}
print_stats("after replacing ripped up cells");
for (auto cell : sorted(ctx->cells))
if (get_constraints_distance(ctx, cell.second) != 0)
log_error("constraint satisfaction check failed for cell '%s' at Bel '%s'\n", cell.first.c_str(ctx),

2
common/placer1.cc
View File

@ -395,7 +395,7 @@ private:
if (other != IdString())
new_dist += get_constraints_distance(ctx, other_cell);
delta = new_metric - curr_metric;
delta += (1 / temp) * (new_dist - old_dist);
delta += (10 / temp) * (new_dist - old_dist);
n_move++;
// SA acceptance criterea
if (delta < 0 || (temp > 1e-6 && (ctx->rng() / float(0x3fffffff)) <= std::exp(-delta / temp))) {