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HeAP: Make strict legalisation wirelength driven where needed

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Signed-off-by: David Shah <dave@ds0.me>
This commit is contained in:
David Shah 2019-01-25 19:24:54 +00:00
parent 8295f997ae
commit fb02fc69c6
1 changed files with 62 additions and 6 deletions
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68
common/placer_heap.cc
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@ -749,16 +749,23 @@ class HeAPPlacer
auto &fb = fast_bels.at(bt);
int radius = 0;
int iter = 0;
int iter_at_radius = 0;
bool placed = false;
BelId bestBel;
int best_inp_len = std::numeric_limits<int>::max();
while (!placed) {
int nx = ctx->rng(2 * radius + 1) + std::max(cell_locs.at(ci->name).x - radius, 0);
int ny = ctx->rng(2 * radius + 1) + std::max(cell_locs.at(ci->name).y - radius, 0);
iter++;
if ((iter % (20 * (radius + 1))) == 0)
iter_at_radius++;
if (iter >= (10 * (radius + 1))) {
radius = std::min(std::max(max_x, max_y), radius + 1);
iter_at_radius = 0;
iter = 0;
}
if (nx < 0 || nx > max_x)
continue;
if (ny < 0 || ny > max_y)
@ -774,22 +781,61 @@ class HeAPPlacer
if (fb.at(nx).at(ny).empty())
continue;
int need_to_explore = 2 * radius;
if (iter_at_radius >= need_to_explore && bestBel != BelId()) {
CellInfo *bound = ctx->getBoundBelCell(bestBel);
if (bound != nullptr) {
ctx->unbindBel(bound->bel);
remaining.emplace(chain_size[bound->name], bound->name);
}
ctx->bindBel(bestBel, ci, STRENGTH_WEAK);
placed = true;
Loc loc = ctx->getBelLocation(bestBel);
cell_locs[ci->name].x = loc.x;
cell_locs[ci->name].y = loc.y;
break;
}
if (ci->constr_children.empty()) {
for (auto sz : fb.at(nx).at(ny)) {
if (ctx->checkBelAvail(sz) || radius > 1) {
if (ctx->checkBelAvail(sz) || radius > 2) {
CellInfo *bound = ctx->getBoundBelCell(sz);
if (bound != nullptr) {
if (bound->constr_parent != nullptr || !bound->constr_children.empty())
continue;
ctx->unbindBel(bound->bel);
remaining.emplace(chain_size[bound->name], bound->name);
}
ctx->bindBel(sz, ci, STRENGTH_WEAK);
if (require_validity && !ctx->isBelLocationValid(sz)) {
ctx->unbindBel(sz);
if (bound != nullptr)
ctx->bindBel(sz, bound, STRENGTH_WEAK);
} else if (iter_at_radius < need_to_explore) {
ctx->unbindBel(sz);
if (bound != nullptr)
ctx->bindBel(sz, bound, STRENGTH_WEAK);
int input_len = 0;
for (auto &port : ci->ports) {
auto &p = port.second;
if (p.type != PORT_IN || p.net == nullptr || p.net->driver.cell == nullptr)
continue;
CellInfo *drv = p.net->driver.cell;
auto drv_loc = cell_locs.find(drv->name);
if (drv_loc == cell_locs.end())
continue;
if (drv_loc->second.global)
continue;
input_len += std::abs(drv_loc->second.x - nx) + std::abs(drv_loc->second.y - ny);
}
if (input_len < best_inp_len) {
best_inp_len = input_len;
bestBel = sz;
}
break;
} else {
if (bound != nullptr)
remaining.emplace(chain_size[bound->name], bound->name);
Loc loc = ctx->getBelLocation(sz);
cell_locs[ci->name].x = loc.x;
cell_locs[ci->name].y = loc.y;
@ -802,6 +848,7 @@ class HeAPPlacer
// FIXME
NPNR_ASSERT(false);
}
}
}
auto endt = std::chrono::high_resolution_clock::now();
@ -843,6 +890,13 @@ class HeAPPlacer
auto startt = std::chrono::high_resolution_clock::now();
init();
find_overused_regions();
for (auto &r : regions) {
if (merged_regions.count(r.id))
continue;
log_info("%s (%d, %d) |_> (%d, %d) %d/%d\n", beltype.c_str(ctx), r.x0, r.y0, r.x1, r.y1, r.cells,
r.bels);
}
log_break();
expand_regions();
std::queue<std::pair<int, bool>> workqueue;
std::vector<std::pair<double, double>> orig;
@ -1298,7 +1352,7 @@ class HeAPPlacer
}
// Split region into up to 10 (K) bins
int K = std::min<int>(N, 10);
std::vector<std::pair<int, double>> bin_bounds; // [start, end]
std::vector<std::pair<int, double>> bin_bounds; // [(cell start, area start)]
bin_bounds.emplace_back(cells_start, area_l);
for (int i = 1; i < K; i++)
bin_bounds.emplace_back(cells_start + (N * i) / K,
@ -1313,12 +1367,14 @@ class HeAPPlacer
: p->cell_locs.at(cut_cells.at(bl.first)->name).rawx;
double orig_right = dir ? p->cell_locs.at(cut_cells.at(br.first - 1)->name).rawy
: p->cell_locs.at(cut_cells.at(br.first - 1)->name).rawx;
double m = (br.second - bl.second) / (1 + orig_right - orig_left);
double m = (br.second - bl.second) / std::max(0.00001, orig_right - orig_left);
for (int j = bl.first; j < br.first; j++) {
auto &pos = dir ? p->cell_locs.at(cut_cells.at(j)->name).rawy
: p->cell_locs.at(cut_cells.at(j)->name).rawx;
double orig_pos = pos;
NPNR_ASSERT(pos >= orig_left && pos <= orig_right);
pos = bl.second + m * (pos - orig_left);
//log("[%f, %f] -> [%f, %f]: %f -> %f\n", orig_left, orig_right, bl.second, br.second, orig_pos, pos);
}
}
};