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static: Respect region constraints 

Signed-off-by: gatecat <gatecat@ds0.me>
This commit is contained in:
gatecat 2026-06-17 13:19:51 +02:00
parent 175787b2f0
commit 57682fe537
1 changed files with 95 additions and 8 deletions
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103
common/place/placer_static.cc
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@ -262,6 +262,8 @@ class StaticPlacer
bool fft_debug = false;
bool dump_density = false;
dict<IdString, BoundingBox> constraint_region_bounds_bel, constraint_region_bounds_place;
// legalisation queue
std::priority_queue<std::pair<int, IdString>> to_legalise;
@ -282,6 +284,49 @@ class StaticPlacer
ctx->bindBel(bel, ci, STRENGTH_USER);
}
}
// Determine bounding boxes of region constraints in both bel and placer coordinates
for (auto &region : ctx->region) {
Region *r = region.second.get();
BoundingBox bel_bb, place_bb;
if (r->constr_bels) {
bel_bb.x0 = std::numeric_limits<int>::max();
bel_bb.x1 = std::numeric_limits<int>::min();
bel_bb.y0 = std::numeric_limits<int>::max();
bel_bb.y1 = std::numeric_limits<int>::min();
place_bb.x0 = std::numeric_limits<int>::max();
place_bb.x1 = std::numeric_limits<int>::min();
place_bb.y0 = std::numeric_limits<int>::max();
place_bb.y1 = std::numeric_limits<int>::min();
for (auto bel : r->bels) {
Loc loc = ctx->getBelLocation(bel);
bel_bb.x0 = std::min(bel_bb.x0, loc.x);
bel_bb.x1 = std::max(bel_bb.x1, loc.x);
bel_bb.y0 = std::min(bel_bb.y0, loc.y);
bel_bb.y1 = std::max(bel_bb.y1, loc.y);
Loc place_loc = get_place_loc(loc);
place_bb.x0 = std::min(place_bb.x0, place_loc.x);
place_bb.x1 = std::max(place_bb.x1, place_loc.x);
place_bb.y0 = std::min(place_bb.y0, place_loc.y);
place_bb.y1 = std::max(place_bb.y1, place_loc.y);
}
} else {
bel_bb.x0 = 0;
bel_bb.y0 = 0;
bel_bb.x1 = bel_width - 1;
bel_bb.y1 = bel_height - 1;
place_bb.x0 = 0;
place_bb.y0 = 0;
place_bb.x1 = width - 1;
place_bb.y1 = height - 1;
}
constraint_region_bounds_bel[r->name] = bel_bb;
constraint_region_bounds_place[r->name] = place_bb;
}
}
bool lookup_group(const CellInfo *ci, int &group, StaticRect &rect)
@ -422,7 +467,7 @@ class StaticPlacer
const float pi = 3.141592653589793f;
RealPair rand_loc()
RealPair rand_loc(Region *region = nullptr)
{
// Box-muller
float u1 = ctx->rngf(1.0f);
@ -432,8 +477,16 @@ class StaticPlacer
float m = std::sqrt(-2.f * std::log(u1));
float z0 = m * std::cos(2.f * pi * u2);
float z1 = m * std::sin(2.f * pi * u2);
float x = (width / 2.f) + (width / 250.f) * z0;
float y = (height / 2.f) + (height / 250.f) * z1;
float cx = (width / 2.f), cy = (height / 2.f);
if (region) {
const auto &bounds = constraint_region_bounds_place.at(region->name);
cx = (bounds.x0 + bounds.x1) / 2.f;
cy = (bounds.y0 + bounds.y1) / 2.f;
}
float x = cx + (width / 250.f) * z0;
float y = cy + (height / 250.f) * z1;
x = std::min<float>(width - 1.f, std::max<float>(x, 0));
y = std::min<float>(height - 1.f, std::max<float>(y, 0));
return RealPair(x, y);
@ -452,6 +505,15 @@ class StaticPlacer
}
}
RealPair limit_to_reg(Region *reg, RealPair val)
{
if (reg == nullptr)
return val;
const auto &b = constraint_region_bounds_place[reg->name];
return RealPair(std::max<float>(std::min<float>(val.x, b.x1), b.x0),
std::max<float>(std::min<float>(val.y, b.y1), b.y0));
}
void init_cells()
{
log_info("⌁ initialising cells...\n");
@ -490,7 +552,7 @@ class StaticPlacer
m.cells[ClusterGroupKey(delta.x, delta.y, cell_group)].push_back(ci);
} else {
// Non-clustered cells can be processed already
int idx = add_cell(rect, cell_group, rand_loc(), ci);
int idx = add_cell(rect, cell_group, rand_loc(ci->region), ci);
ci->udata = idx;
auto &mc = mcells.at(idx);
mc.pin_count += int(ci->ports.size());
@ -540,7 +602,8 @@ class StaticPlacer
}
// Now add the moveable cell
if (cluster_size.area() > 0) {
int idx = add_cell(cluster_size, kv.first.group, rand_loc(), kv.second.front());
int idx = add_cell(cluster_size, kv.first.group, rand_loc(kv.second.front()->region),
kv.second.front());
auto &mc = mcells.at(idx);
if (kv.second.front()->bel != BelId()) {
// Currently; treat all ready-placed cells as fixed (eventually we might do incremental ripups
@ -1188,7 +1251,8 @@ class StaticPlacer
log_info("iter=%d steplen=%f a=%f penalty=[%s]\n", iter, steplen, nesterov_a, penalty_str.c_str());
float a_next = (1.0f + std::sqrt(4.0f * nesterov_a * nesterov_a + 1)) / 2.0f;
// Update positions using Nesterov's
for (auto &cell : mcells) {
for (int idx = 0; idx < int(mcells.size()); idx++) {
auto &cell = mcells.at(idx);
if (cell.is_fixed || cell.is_dark)
continue;
// save current position in last_pos
@ -1198,6 +1262,10 @@ class StaticPlacer
cell.pos = clamp_loc(cell.ref_pos - cell.ref_total_grad * steplen);
// compute reference position
cell.ref_pos = clamp_loc(cell.pos + (cell.pos - cell.last_pos) * ((nesterov_a - 1) / a_next));
if (idx < int(ccells.size()) && ccells.at(idx).base_cell->region != nullptr) {
cell.pos = limit_to_reg(ccells.at(idx).base_cell->region, cell.pos);
cell.ref_pos = limit_to_reg(ccells.at(idx).base_cell->region, cell.ref_pos);
}
}
nesterov_a = a_next;
update_chains();
@ -1354,8 +1422,27 @@ class StaticPlacer
cx = place_x_to_bel_x.at(std::max(0, std::min(cx, width - 1)));
cy = place_y_to_bel_y.at(std::max(0, std::min(cy, height - 1)));
}
int nx = ctx->rng(2 * rx + 1) + std::max(cx - rx, 0);
int ny = ctx->rng(2 * ry + 1) + std::max(cy - ry, 0);
int x0 = std::max(cx - rx, 0);
int y0 = std::max(cy - ry, 0);
int x1 = cx + rx;
int y1 = cy + ry;
if (ci->region != nullptr) {
auto &r = constraint_region_bounds_bel[ci->region->name];
// Clamp search box to a region
x0 = std::max(x0, r.x0);
y0 = std::max(y0, r.y0);
x1 = std::min(x1, r.x1);
y1 = std::min(y1, r.y1);
if (x0 > x1)
std::swap(x0, x1);
if (y0 > y1)
std::swap(y0, y1);
}
int nx = ctx->rng(x1 - x0 + 1) + x0;
int ny = ctx->rng(y1 - y0 + 1) + y0;
iter++;
iter_at_radius++;