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HeAP: Implement 'all+rotate' HeAP strategy

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Signed-off-by: David Shah <dave@ds0.me>
This commit is contained in:
David Shah 2019-01-25 14:04:19 +00:00
parent 3dedc62593
commit ba1e05f16b
3 changed files with 56 additions and 30 deletions
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2
common/placer1.cc
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@ -259,7 +259,7 @@ class SAPlacer
wirelen_t min_wirelen = curr_wirelen_cost;
int n_no_progress = 0;
temp = refine ? 1e-8 : cfg.startTemp;
temp = refine ? 1e-7 : cfg.startTemp;
// Main simulated annealing loop
for (int iter = 1;; iter++) {

80
common/placer_heap.cc
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@ -134,10 +134,11 @@ class HeAPPlacer
log_info("Initial placer starting hpwl = %d\n", int(hpwl));
for (int i = 0; i < 4; i++) {
setup_solve_cells();
auto solve_startt = std::chrono::high_resolution_clock::now();
std::thread xaxis([&](){build_solve_direction(false, -1);});
std::thread yaxis([&](){build_solve_direction(true, -1);});
auto solve_endt = std::chrono::high_resolution_clock::now();
solve_time += std::chrono::duration<double>(solve_endt - solve_startt).count();
xaxis.join();
yaxis.join();
@ -158,36 +159,59 @@ class HeAPPlacer
std::vector<std::tuple<CellInfo*, BelId, PlaceStrength>> solution;
std::vector<std::unordered_set<IdString>> heap_runs;
std::unordered_set<IdString> all_celltypes;
for (auto cell : place_cells) {
if (!all_celltypes.count(cell->type)) {
heap_runs.push_back(std::unordered_set<IdString>{cell->type});
all_celltypes.insert(cell->type);
}
}
heap_runs.push_back(all_celltypes);
while (!valid || (stalled < 5 && (solved_hpwl <= legal_hpwl * 0.8))) {
if (!valid && ((solved_hpwl > legal_hpwl * 0.8) || (stalled > 5))) {
stalled = 0;
best_hpwl = std::numeric_limits<wirelen_t>::max();
valid = true;
}
setup_solve_cells();
for (auto &run : heap_runs) {
setup_solve_cells(&run);
if (solve_cells.empty())
continue;
// Heuristic: don't bother with threading below a certain size
auto solve_startt = std::chrono::high_resolution_clock::now();
std::thread xaxis([&](){build_solve_direction(false, (iter == 0) ? -1 : iter);});
std::thread yaxis([&](){build_solve_direction(true, (iter == 0) ? -1 : iter);});
if (solve_cells.size() < 500) {
build_solve_direction(false, (iter == 0) ? -1 : iter);
build_solve_direction(true, (iter == 0) ? -1 : iter);
} else {
std::thread xaxis([&](){build_solve_direction(false, (iter == 0) ? -1 : iter);});
std::thread yaxis([&](){build_solve_direction(true, (iter == 0) ? -1 : iter);});
xaxis.join();
yaxis.join();
}
auto solve_endt = std::chrono::high_resolution_clock::now();
solve_time += std::chrono::duration<double>(solve_endt - solve_startt).count();
update_all_chains();
solved_hpwl = total_hpwl();
log_info("Solved HPWL = %d\n", int(solved_hpwl));
xaxis.join();
yaxis.join();
update_all_chains();
for (auto type : sorted(run))
CutLegaliser(this, type).run();
update_all_chains();
solved_hpwl = total_hpwl();
log_info("Solved HPWL = %d\n", int(solved_hpwl));
update_all_chains();
legal_hpwl = total_hpwl();
log_info("Spread HPWL = %d\n", int(legal_hpwl));
legalise_placement_simple(valid);
update_all_chains();
update_all_chains();
CutLegaliser(this, ctx->id("ICESTORM_LC")).run();
CutLegaliser(this, ctx->id("ICESTORM_RAM")).run();
legal_hpwl = total_hpwl();
log_info("Legalised HPWL = %d (%s)\n", int(legal_hpwl), valid ? "valid" : "invalid");
update_all_chains();
legal_hpwl = total_hpwl();
log_info("Spread HPWL = %d\n", int(legal_hpwl));
legalise_placement_simple(valid);
update_all_chains();
legal_hpwl = total_hpwl();
log_info("Legalised HPWL = %d (%s)\n", int(legal_hpwl), valid ? "valid" : "invalid");
}
if (ctx->timing_driven)
get_criticalities(ctx, &net_crit);
@ -624,7 +648,6 @@ class HeAPPlacer
// Build the system of equations for either X or Y
void solve_equations(EquationSystem<double> &es, bool yaxis)
{
auto startt = std::chrono::high_resolution_clock::now();
// Return the x or y position of a cell, depending on ydir
auto cell_pos = [&](CellInfo *cell) { return yaxis ? cell_locs.at(cell->name).y : cell_locs.at(cell->name).x; };
std::vector<double> vals;
@ -638,8 +661,6 @@ class HeAPPlacer
cell_locs.at(solve_cells.at(i)->name).rawx = vals.at(i);
cell_locs.at(solve_cells.at(i)->name).x = std::min(max_x, std::max(0, int(vals.at(i))));
}
auto endt = std::chrono::high_resolution_clock::now();
solve_time += std::chrono::duration<double>(endt - startt).count();
}
// Compute HPWL
@ -1111,9 +1132,14 @@ class HeAPPlacer
if (!reg.overused())
break;
}
if (!changed)
log_error("Failed to expand region (%d, %d) |_> (%d, %d) of %d %ss\n", reg.x0, reg.y0, reg.x1,
reg.y1, reg.cells, beltype.c_str(ctx));
if (!changed) {
if (reg.cells > reg.bels)
log_error("Failed to expand region (%d, %d) |_> (%d, %d) of %d %ss\n", reg.x0, reg.y0, reg.x1,
reg.y1, reg.cells, beltype.c_str(ctx));
else
break;
}
}
}
}

4
common/placer_math.c
View File

@ -4,7 +4,7 @@
#include <assert.h>
void taucif_init_solver() {
taucs_logfile("stdout");
//taucs_logfile("stdout");
}
struct taucif_system {
@ -39,7 +39,7 @@ void taucif_finalise_matrix(struct taucif_system *sys) {
int taucif_solve_system(struct taucif_system *sys, double *x, double *rhs) {
// FIXME: preconditioner, droptol??
taucs_ccs_matrix* precond_mat = taucs_ccs_factor_llt(sys->mat, 1e-3, 0);
taucs_ccs_matrix* precond_mat = taucs_ccs_factor_llt(sys->mat, 1e-2, 0);
if (precond_mat == NULL)
return -1;
// FIXME: itermax, convergetol