2fdf41ac01
Previously only the first loop skipped cells with high belStrength, but they can't be processed by the second loop either, so skip them there too.
1860 lines
80 KiB
C++
1860 lines
80 KiB
C++
/*
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* nextpnr -- Next Generation Place and Route
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*
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* Copyright (C) 2019 David Shah <david@symbioticeda.com>
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*
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* Permission to use, copy, modify, and/or distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*
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* [[cite]] HeAP
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* Analytical Placement for Heterogeneous FPGAs, Marcel Gort and Jason H. Anderson
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* https://janders.eecg.utoronto.ca/pdfs/marcelfpl12.pdf
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*
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* [[cite]] SimPL
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* SimPL: An Effective Placement Algorithm, Myung-Chul Kim, Dong-Jin Lee and Igor L. Markov
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* http://www.ece.umich.edu/cse/awards/pdfs/iccad10-simpl.pdf
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*
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* Notable changes from the original algorithm
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* - Following the other nextpnr placer, Bels are placed rather than CLBs. This means a strict legalisation pass is
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* added in addition to coarse legalisation (referred to as "spreading" to avoid confusion with strict legalisation)
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* as described in HeAP to ensure validity. This searches random bels in the vicinity of the position chosen by
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* spreading, with diameter increasing over iterations, with a heuristic to prefer lower wirelength choices.
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* - To make the placer timing-driven, the bound2bound weights are multiplied by (1 + 10 * crit^2)
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*/
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#ifdef WITH_HEAP
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#include "placer_heap.h"
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#include <Eigen/Core>
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#include <Eigen/IterativeLinearSolvers>
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#include <boost/optional.hpp>
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#include <chrono>
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#include <deque>
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#include <fstream>
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#include <numeric>
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#include <queue>
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#include <tuple>
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#include <unordered_map>
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#include "fast_bels.h"
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#include "log.h"
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#include "nextpnr.h"
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#include "place_common.h"
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#include "placer1.h"
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#include "scope_lock.h"
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#include "timing.h"
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#include "util.h"
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NEXTPNR_NAMESPACE_BEGIN
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namespace {
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// A simple internal representation for a sparse system of equations Ax = rhs
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// This is designed to decouple the functions that build the matrix to the engine that
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// solves it, and the representation that requires
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template <typename T> struct EquationSystem
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{
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EquationSystem(size_t rows, size_t cols)
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{
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A.resize(cols);
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rhs.resize(rows);
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}
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// Simple sparse format, easy to convert to CCS for solver
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std::vector<std::vector<std::pair<int, T>>> A; // col -> (row, x[row, col]) sorted by row
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std::vector<T> rhs; // RHS vector
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void reset()
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{
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for (auto &col : A)
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col.clear();
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std::fill(rhs.begin(), rhs.end(), T());
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}
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void add_coeff(int row, int col, T val)
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{
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auto &Ac = A.at(col);
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// Binary search
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int b = 0, e = int(Ac.size()) - 1;
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while (b <= e) {
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int i = (b + e) / 2;
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if (Ac.at(i).first == row) {
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Ac.at(i).second += val;
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return;
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}
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if (Ac.at(i).first > row)
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e = i - 1;
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else
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b = i + 1;
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}
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Ac.insert(Ac.begin() + b, std::make_pair(row, val));
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}
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void add_rhs(int row, T val) { rhs[row] += val; }
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void solve(std::vector<T> &x, float tolerance)
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{
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using namespace Eigen;
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if (x.empty())
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return;
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NPNR_ASSERT(x.size() == A.size());
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VectorXd vx(x.size()), vb(rhs.size());
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SparseMatrix<T> mat(A.size(), A.size());
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std::vector<int> colnnz;
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for (auto &Ac : A)
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colnnz.push_back(int(Ac.size()));
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mat.reserve(colnnz);
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for (int col = 0; col < int(A.size()); col++) {
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auto &Ac = A.at(col);
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for (auto &el : Ac)
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mat.insert(el.first, col) = el.second;
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}
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for (int i = 0; i < int(x.size()); i++)
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vx[i] = x.at(i);
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for (int i = 0; i < int(rhs.size()); i++)
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vb[i] = rhs.at(i);
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ConjugateGradient<SparseMatrix<T>, Lower | Upper> solver;
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solver.setTolerance(tolerance);
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VectorXd xr = solver.compute(mat).solveWithGuess(vb, vx);
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for (int i = 0; i < int(x.size()); i++)
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x.at(i) = xr[i];
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// for (int i = 0; i < int(x.size()); i++)
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// log_info("x[%d] = %f\n", i, x.at(i));
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}
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};
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} // namespace
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class HeAPPlacer
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{
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public:
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HeAPPlacer(Context *ctx, PlacerHeapCfg cfg)
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: ctx(ctx), cfg(cfg), fast_bels(ctx, /*check_bel_available=*/true, -1), tmg(ctx)
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{
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Eigen::initParallel();
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tmg.setup_only = true;
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tmg.setup();
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}
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bool place()
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{
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auto startt = std::chrono::high_resolution_clock::now();
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ScopeLock<Context> lock(ctx);
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place_constraints();
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build_fast_bels();
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seed_placement();
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update_all_chains();
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wirelen_t hpwl = total_hpwl();
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log_info("Creating initial analytic placement for %d cells, random placement wirelen = %d.\n",
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int(place_cells.size()), int(hpwl));
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for (int i = 0; i < 4; i++) {
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setup_solve_cells();
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auto solve_startt = std::chrono::high_resolution_clock::now();
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#ifdef NPNR_DISABLE_THREADS
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build_solve_direction(false, -1);
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build_solve_direction(true, -1);
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#else
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boost::thread xaxis([&]() { build_solve_direction(false, -1); });
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build_solve_direction(true, -1);
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xaxis.join();
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#endif
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auto solve_endt = std::chrono::high_resolution_clock::now();
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solve_time += std::chrono::duration<double>(solve_endt - solve_startt).count();
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update_all_chains();
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hpwl = total_hpwl();
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log_info(" at initial placer iter %d, wirelen = %d\n", i, int(hpwl));
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}
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wirelen_t solved_hpwl = 0, spread_hpwl = 0, legal_hpwl = 0, best_hpwl = std::numeric_limits<wirelen_t>::max();
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int iter = 0, stalled = 0;
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std::vector<std::tuple<CellInfo *, BelId, PlaceStrength>> solution;
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std::vector<std::unordered_set<BelBucketId>> heap_runs;
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std::unordered_set<BelBucketId> all_buckets;
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std::unordered_map<BelBucketId, int> bucket_count;
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for (auto cell : place_cells) {
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BelBucketId bucket = ctx->getBelBucketForCellType(cell->type);
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if (!all_buckets.count(bucket)) {
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heap_runs.push_back(std::unordered_set<BelBucketId>{bucket});
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all_buckets.insert(bucket);
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}
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bucket_count[bucket]++;
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}
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// If more than 98% of cells are one cell type, always solve all at once
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// Otherwise, follow full HeAP strategy of rotate&all
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for (auto &c : bucket_count) {
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if (c.second >= 0.98 * int(place_cells.size())) {
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heap_runs.clear();
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break;
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}
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}
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if (cfg.placeAllAtOnce) {
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// Never want to deal with LUTs, FFs, MUXFxs separately,
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// for now disable all single-cell-type runs and only have heterogeneous
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// runs
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heap_runs.clear();
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}
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heap_runs.push_back(all_buckets);
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// The main HeAP placer loop
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log_info("Running main analytical placer.\n");
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while (stalled < 5 && (solved_hpwl <= legal_hpwl * 0.8)) {
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// Alternate between particular bel types and all bels
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for (auto &run : heap_runs) {
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auto run_startt = std::chrono::high_resolution_clock::now();
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setup_solve_cells(&run);
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if (solve_cells.empty())
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continue;
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// Heuristic: don't bother with threading below a certain size
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auto solve_startt = std::chrono::high_resolution_clock::now();
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// Build the connectivity matrix and run the solver; multithreaded between x and y axes if applicable
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#ifndef NPNR_DISABLE_THREADS
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if (solve_cells.size() >= 500) {
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boost::thread xaxis([&]() { build_solve_direction(false, (iter == 0) ? -1 : iter); });
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build_solve_direction(true, (iter == 0) ? -1 : iter);
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xaxis.join();
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} else
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#endif
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{
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build_solve_direction(false, (iter == 0) ? -1 : iter);
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build_solve_direction(true, (iter == 0) ? -1 : iter);
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}
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auto solve_endt = std::chrono::high_resolution_clock::now();
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solve_time += std::chrono::duration<double>(solve_endt - solve_startt).count();
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update_all_chains();
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solved_hpwl = total_hpwl();
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update_all_chains();
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// Run the spreader
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for (const auto &group : cfg.cellGroups)
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CutSpreader(this, group).run();
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for (auto type : sorted(run))
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if (std::all_of(cfg.cellGroups.begin(), cfg.cellGroups.end(),
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[type](const std::unordered_set<BelBucketId> &grp) { return !grp.count(type); }))
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CutSpreader(this, {type}).run();
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// Run strict legalisation to find a valid bel for all cells
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update_all_chains();
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spread_hpwl = total_hpwl();
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legalise_placement_strict(true);
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update_all_chains();
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legal_hpwl = total_hpwl();
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auto run_stopt = std::chrono::high_resolution_clock::now();
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IdString bucket_name = ctx->getBelBucketName(*run.begin());
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log_info(" at iteration #%d, type %s: wirelen solved = %d, spread = %d, legal = %d; time = %.02fs\n",
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iter + 1, (run.size() > 1 ? "ALL" : bucket_name.c_str(ctx)), int(solved_hpwl),
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int(spread_hpwl), int(legal_hpwl),
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std::chrono::duration<double>(run_stopt - run_startt).count());
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}
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// Update timing weights
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if (cfg.timing_driven)
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tmg.run();
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if (legal_hpwl < best_hpwl) {
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best_hpwl = legal_hpwl;
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stalled = 0;
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// Save solution
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solution.clear();
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for (auto cell : sorted(ctx->cells)) {
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solution.emplace_back(cell.second, cell.second->bel, cell.second->belStrength);
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}
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} else {
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++stalled;
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}
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for (auto &cl : cell_locs) {
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cl.second.legal_x = cl.second.x;
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cl.second.legal_y = cl.second.y;
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}
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ctx->yield();
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++iter;
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}
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// Apply saved solution
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for (auto &sc : solution) {
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CellInfo *cell = std::get<0>(sc);
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if (cell->bel != BelId())
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ctx->unbindBel(cell->bel);
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}
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for (auto &sc : solution) {
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CellInfo *cell;
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BelId bel;
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PlaceStrength strength;
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std::tie(cell, bel, strength) = sc;
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ctx->bindBel(bel, cell, strength);
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}
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for (auto cell : sorted(ctx->cells)) {
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if (cell.second->bel == BelId())
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log_error("Found unbound cell %s\n", cell.first.c_str(ctx));
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if (ctx->getBoundBelCell(cell.second->bel) != cell.second)
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log_error("Found cell %s with mismatched binding\n", cell.first.c_str(ctx));
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if (ctx->debug)
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log_info("AP soln: %s -> %s\n", cell.first.c_str(ctx), ctx->nameOfBel(cell.second->bel));
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}
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bool any_bad_placements = false;
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for (auto bel : ctx->getBels()) {
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CellInfo *cell = ctx->getBoundBelCell(bel);
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if (!ctx->isBelLocationValid(bel)) {
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std::string cell_text = "no cell";
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if (cell != nullptr)
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cell_text = std::string("cell '") + ctx->nameOf(cell) + "'";
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log_warning("post-placement validity check failed for Bel '%s' "
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"(%s)\n",
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ctx->nameOfBel(bel), cell_text.c_str());
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any_bad_placements = true;
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}
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}
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if (any_bad_placements) {
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return false;
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}
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auto endtt = std::chrono::high_resolution_clock::now();
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log_info("HeAP Placer Time: %.02fs\n", std::chrono::duration<double>(endtt - startt).count());
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log_info(" of which solving equations: %.02fs\n", solve_time);
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log_info(" of which spreading cells: %.02fs\n", cl_time);
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log_info(" of which strict legalisation: %.02fs\n", sl_time);
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ctx->check();
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lock.unlock_early();
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if (!placer1_refine(ctx, Placer1Cfg(ctx))) {
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return false;
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}
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return true;
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}
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private:
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Context *ctx;
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PlacerHeapCfg cfg;
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int max_x = 0, max_y = 0;
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FastBels fast_bels;
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std::unordered_map<IdString, std::tuple<int, int>> bel_types;
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TimingAnalyser tmg;
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struct BoundingBox
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{
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// Actual bounding box
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int x0 = 0, x1 = 0, y0 = 0, y1 = 0;
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};
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std::unordered_map<IdString, BoundingBox> constraint_region_bounds;
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// In some cases, we can't use bindBel because we allow overlap in the earlier stages. So we use this custom
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// structure instead
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struct CellLocation
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{
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int x, y;
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int legal_x, legal_y;
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double rawx, rawy;
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bool locked, global;
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};
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std::unordered_map<IdString, CellLocation> cell_locs;
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// The set of cells that we will actually place. This excludes locked cells and children cells of macros/chains
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// (only the root of each macro is placed.)
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std::vector<CellInfo *> place_cells;
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// The cells in the current equation being solved (a subset of place_cells in some cases, where we only place
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// cells of a certain type)
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std::vector<CellInfo *> solve_cells;
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// For cells in a chain, this is the ultimate root cell of the chain (sometimes this is not constr_parent
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// where chains are within chains
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std::unordered_map<IdString, CellInfo *> chain_root;
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std::unordered_map<IdString, int> chain_size;
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// The offset from chain_root to a cell in the chain
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std::unordered_map<IdString, std::pair<int, int>> cell_offsets;
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// Performance counting
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double solve_time = 0, cl_time = 0, sl_time = 0;
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// Place cells with the BEL attribute set to constrain them
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void place_constraints()
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{
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size_t placed_cells = 0;
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// Initial constraints placer
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for (auto &cell_entry : ctx->cells) {
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CellInfo *cell = cell_entry.second.get();
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auto loc = cell->attrs.find(ctx->id("BEL"));
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if (loc != cell->attrs.end()) {
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std::string loc_name = loc->second.as_string();
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BelId bel = ctx->getBelByNameStr(loc_name);
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if (bel == BelId()) {
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log_error("No Bel named \'%s\' located for "
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"this chip (processing BEL attribute on \'%s\')\n",
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loc_name.c_str(), cell->name.c_str(ctx));
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}
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if (!ctx->isValidBelForCellType(cell->type, bel)) {
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IdString bel_type = ctx->getBelType(bel);
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log_error("Bel \'%s\' of type \'%s\' does not match cell "
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"\'%s\' of type \'%s\'\n",
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loc_name.c_str(), bel_type.c_str(ctx), cell->name.c_str(ctx), cell->type.c_str(ctx));
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}
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auto bound_cell = ctx->getBoundBelCell(bel);
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if (bound_cell) {
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log_error("Cell \'%s\' cannot be bound to bel \'%s\' since it is already bound to cell \'%s\'\n",
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cell->name.c_str(ctx), loc_name.c_str(), bound_cell->name.c_str(ctx));
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}
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ctx->bindBel(bel, cell, STRENGTH_USER);
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if (!ctx->isBelLocationValid(bel)) {
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IdString bel_type = ctx->getBelType(bel);
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log_error("Bel \'%s\' of type \'%s\' is not valid for cell "
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"\'%s\' of type \'%s\'\n",
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loc_name.c_str(), bel_type.c_str(ctx), cell->name.c_str(ctx), cell->type.c_str(ctx));
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}
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placed_cells++;
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}
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}
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log_info("Placed %d cells based on constraints.\n", int(placed_cells));
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ctx->yield();
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}
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void build_fast_bels()
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{
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for (auto bel : ctx->getBels()) {
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if (!ctx->checkBelAvail(bel))
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continue;
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Loc loc = ctx->getBelLocation(bel);
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max_x = std::max(max_x, loc.x);
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max_y = std::max(max_y, loc.y);
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}
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std::unordered_set<IdString> cell_types_in_use;
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std::unordered_set<BelBucketId> buckets_in_use;
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for (auto cell : sorted(ctx->cells)) {
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IdString cell_type = cell.second->type;
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cell_types_in_use.insert(cell_type);
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BelBucketId bucket = ctx->getBelBucketForCellType(cell_type);
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buckets_in_use.insert(bucket);
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}
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for (auto cell_type : cell_types_in_use) {
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fast_bels.addCellType(cell_type);
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}
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for (auto bucket : buckets_in_use) {
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fast_bels.addBelBucket(bucket);
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}
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// Determine bounding boxes of region constraints
|
|
for (auto ®ion : sorted(ctx->region)) {
|
|
Region *r = region.second;
|
|
BoundingBox bb;
|
|
if (r->constr_bels) {
|
|
bb.x0 = std::numeric_limits<int>::max();
|
|
bb.x1 = std::numeric_limits<int>::min();
|
|
bb.y0 = std::numeric_limits<int>::max();
|
|
bb.y1 = std::numeric_limits<int>::min();
|
|
for (auto bel : r->bels) {
|
|
Loc loc = ctx->getBelLocation(bel);
|
|
bb.x0 = std::min(bb.x0, loc.x);
|
|
bb.x1 = std::max(bb.x1, loc.x);
|
|
bb.y0 = std::min(bb.y0, loc.y);
|
|
bb.y1 = std::max(bb.y1, loc.y);
|
|
}
|
|
} else {
|
|
bb.x0 = 0;
|
|
bb.y0 = 0;
|
|
bb.x1 = max_x;
|
|
bb.y1 = max_y;
|
|
}
|
|
constraint_region_bounds[r->name] = bb;
|
|
}
|
|
}
|
|
|
|
// Build and solve in one direction
|
|
void build_solve_direction(bool yaxis, int iter)
|
|
{
|
|
for (int i = 0; i < 5; i++) {
|
|
EquationSystem<double> esx(solve_cells.size(), solve_cells.size());
|
|
build_equations(esx, yaxis, iter);
|
|
solve_equations(esx, yaxis);
|
|
}
|
|
}
|
|
|
|
// Check if a cell has any meaningful connectivity
|
|
bool has_connectivity(CellInfo *cell)
|
|
{
|
|
for (auto port : cell->ports) {
|
|
if (port.second.net != nullptr && port.second.net->driver.cell != nullptr &&
|
|
!port.second.net->users.empty())
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// Build up a random initial placement, without regard to legality
|
|
// FIXME: Are there better approaches to the initial placement (e.g. greedy?)
|
|
void seed_placement()
|
|
{
|
|
std::unordered_set<IdString> cell_types;
|
|
for (const auto &cell : ctx->cells) {
|
|
cell_types.insert(cell.second->type);
|
|
}
|
|
|
|
std::unordered_set<BelId> bels_used;
|
|
std::unordered_map<IdString, std::deque<BelId>> available_bels;
|
|
|
|
for (auto bel : ctx->getBels()) {
|
|
if (!ctx->checkBelAvail(bel)) {
|
|
continue;
|
|
}
|
|
|
|
for (auto cell_type : cell_types) {
|
|
if (ctx->isValidBelForCellType(cell_type, bel)) {
|
|
available_bels[cell_type].push_back(bel);
|
|
}
|
|
}
|
|
}
|
|
|
|
for (auto &t : available_bels) {
|
|
ctx->shuffle(t.second.begin(), t.second.end());
|
|
}
|
|
|
|
for (auto cell : sorted(ctx->cells)) {
|
|
CellInfo *ci = cell.second;
|
|
if (ci->bel != BelId()) {
|
|
Loc loc = ctx->getBelLocation(ci->bel);
|
|
cell_locs[cell.first].x = loc.x;
|
|
cell_locs[cell.first].y = loc.y;
|
|
cell_locs[cell.first].locked = true;
|
|
cell_locs[cell.first].global = ctx->getBelGlobalBuf(ci->bel);
|
|
} else if (ci->constr_parent == nullptr) {
|
|
bool placed = false;
|
|
int attempt_count = 0;
|
|
while (!placed) {
|
|
++attempt_count;
|
|
if (attempt_count > 25000) {
|
|
log_error("Unable to find a placement location for cell '%s'\n", ci->name.c_str(ctx));
|
|
}
|
|
|
|
// Make sure this cell type is in the available BEL map at
|
|
// all.
|
|
if (!available_bels.count(ci->type)) {
|
|
log_error("Unable to place cell '%s', no BELs remaining to implement cell type '%s'\n",
|
|
ci->name.c_str(ctx), ci->type.c_str(ctx));
|
|
}
|
|
|
|
// Find an unused BEL from bels_for_cell_type.
|
|
auto &bels_for_cell_type = available_bels.at(ci->type);
|
|
BelId bel;
|
|
while (true) {
|
|
if (bels_for_cell_type.empty()) {
|
|
log_error("Unable to place cell '%s', no BELs remaining to implement cell type '%s'\n",
|
|
ci->name.c_str(ctx), ci->type.c_str(ctx));
|
|
}
|
|
|
|
BelId candidate_bel = bels_for_cell_type.back();
|
|
bels_for_cell_type.pop_back();
|
|
if (bels_used.count(candidate_bel)) {
|
|
// candidate_bel has already been used by another
|
|
// cell type, skip it.
|
|
continue;
|
|
}
|
|
|
|
bel = candidate_bel;
|
|
break;
|
|
}
|
|
|
|
Loc loc = ctx->getBelLocation(bel);
|
|
cell_locs[cell.first].x = loc.x;
|
|
cell_locs[cell.first].y = loc.y;
|
|
cell_locs[cell.first].locked = false;
|
|
cell_locs[cell.first].global = ctx->getBelGlobalBuf(bel);
|
|
|
|
// FIXME
|
|
if (has_connectivity(cell.second) && !cfg.ioBufTypes.count(ci->type)) {
|
|
bels_used.insert(bel);
|
|
place_cells.push_back(ci);
|
|
placed = true;
|
|
} else {
|
|
ctx->bindBel(bel, ci, STRENGTH_STRONG);
|
|
if (ctx->isBelLocationValid(bel)) {
|
|
cell_locs[cell.first].locked = true;
|
|
placed = true;
|
|
bels_used.insert(bel);
|
|
} else {
|
|
ctx->unbindBel(bel);
|
|
available_bels.at(ci->type).push_front(bel);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Setup the cells to be solved, returns the number of rows
|
|
int setup_solve_cells(std::unordered_set<BelBucketId> *buckets = nullptr)
|
|
{
|
|
int row = 0;
|
|
solve_cells.clear();
|
|
// First clear the udata of all cells
|
|
for (auto cell : sorted(ctx->cells))
|
|
cell.second->udata = dont_solve;
|
|
// Then update cells to be placed, which excludes cell children
|
|
for (auto cell : place_cells) {
|
|
if (buckets && !buckets->count(ctx->getBelBucketForCellType(cell->type)))
|
|
continue;
|
|
cell->udata = row++;
|
|
solve_cells.push_back(cell);
|
|
}
|
|
// Finally, update the udata of children
|
|
for (auto chained : chain_root)
|
|
ctx->cells.at(chained.first)->udata = chained.second->udata;
|
|
return row;
|
|
}
|
|
|
|
// Update the location of all children of a chain
|
|
void update_chain(CellInfo *cell, CellInfo *root)
|
|
{
|
|
const auto &base = cell_locs[cell->name];
|
|
for (auto child : cell->constr_children) {
|
|
// FIXME: Improve handling of heterogeneous chains
|
|
if (child->type == root->type)
|
|
chain_size[root->name]++;
|
|
if (child->constr_x != child->UNCONSTR)
|
|
cell_locs[child->name].x = std::max(0, std::min(max_x, base.x + child->constr_x));
|
|
else
|
|
cell_locs[child->name].x = base.x; // better handling of UNCONSTR?
|
|
if (child->constr_y != child->UNCONSTR)
|
|
cell_locs[child->name].y = std::max(0, std::min(max_y, base.y + child->constr_y));
|
|
else
|
|
cell_locs[child->name].y = base.y; // better handling of UNCONSTR?
|
|
chain_root[child->name] = root;
|
|
if (!child->constr_children.empty())
|
|
update_chain(child, root);
|
|
}
|
|
}
|
|
|
|
// Update all chains
|
|
void update_all_chains()
|
|
{
|
|
for (auto cell : place_cells) {
|
|
chain_size[cell->name] = 1;
|
|
if (!cell->constr_children.empty())
|
|
update_chain(cell, cell);
|
|
}
|
|
}
|
|
|
|
// Run a function on all ports of a net - including the driver and all users
|
|
template <typename Tf> void foreach_port(NetInfo *net, Tf func)
|
|
{
|
|
if (net->driver.cell != nullptr)
|
|
func(net->driver, -1);
|
|
for (size_t i = 0; i < net->users.size(); i++)
|
|
func(net->users.at(i), i);
|
|
}
|
|
|
|
// Build the system of equations for either X or Y
|
|
void build_equations(EquationSystem<double> &es, bool yaxis, int iter = -1)
|
|
{
|
|
// 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; };
|
|
auto legal_pos = [&](CellInfo *cell) {
|
|
return yaxis ? cell_locs.at(cell->name).legal_y : cell_locs.at(cell->name).legal_x;
|
|
};
|
|
|
|
es.reset();
|
|
|
|
for (auto net : sorted(ctx->nets)) {
|
|
NetInfo *ni = net.second;
|
|
if (ni->driver.cell == nullptr)
|
|
continue;
|
|
if (ni->users.empty())
|
|
continue;
|
|
if (cell_locs.at(ni->driver.cell->name).global)
|
|
continue;
|
|
// Find the bounds of the net in this axis, and the ports that correspond to these bounds
|
|
PortRef *lbport = nullptr, *ubport = nullptr;
|
|
int lbpos = std::numeric_limits<int>::max(), ubpos = std::numeric_limits<int>::min();
|
|
foreach_port(ni, [&](PortRef &port, int user_idx) {
|
|
int pos = cell_pos(port.cell);
|
|
if (pos < lbpos) {
|
|
lbpos = pos;
|
|
lbport = &port;
|
|
}
|
|
if (pos > ubpos) {
|
|
ubpos = pos;
|
|
ubport = &port;
|
|
}
|
|
});
|
|
NPNR_ASSERT(lbport != nullptr);
|
|
NPNR_ASSERT(ubport != nullptr);
|
|
|
|
auto stamp_equation = [&](PortRef &var, PortRef &eqn, double weight) {
|
|
if (eqn.cell->udata == dont_solve)
|
|
return;
|
|
int row = eqn.cell->udata;
|
|
int v_pos = cell_pos(var.cell);
|
|
if (var.cell->udata != dont_solve) {
|
|
es.add_coeff(row, var.cell->udata, weight);
|
|
} else {
|
|
es.add_rhs(row, -v_pos * weight);
|
|
}
|
|
if (cell_offsets.count(var.cell->name)) {
|
|
es.add_rhs(row, -(yaxis ? cell_offsets.at(var.cell->name).second
|
|
: cell_offsets.at(var.cell->name).first) *
|
|
weight);
|
|
}
|
|
};
|
|
|
|
// Add all relevant connections to the matrix
|
|
foreach_port(ni, [&](PortRef &port, int user_idx) {
|
|
int this_pos = cell_pos(port.cell);
|
|
auto process_arc = [&](PortRef *other) {
|
|
if (other == &port)
|
|
return;
|
|
int o_pos = cell_pos(other->cell);
|
|
double weight = 1.0 / (ni->users.size() *
|
|
std::max<double>(1, (yaxis ? cfg.hpwl_scale_y : cfg.hpwl_scale_x) *
|
|
std::abs(o_pos - this_pos)));
|
|
|
|
if (user_idx != -1) {
|
|
weight *= (1.0 + cfg.timingWeight * std::pow(tmg.get_criticality(CellPortKey(port)),
|
|
cfg.criticalityExponent));
|
|
}
|
|
|
|
// If cell 0 is not fixed, it will stamp +w on its equation and -w on the other end's equation,
|
|
// if the other end isn't fixed
|
|
stamp_equation(port, port, weight);
|
|
stamp_equation(port, *other, -weight);
|
|
stamp_equation(*other, *other, weight);
|
|
stamp_equation(*other, port, -weight);
|
|
};
|
|
process_arc(lbport);
|
|
process_arc(ubport);
|
|
});
|
|
}
|
|
if (iter != -1) {
|
|
float alpha = cfg.alpha;
|
|
for (size_t row = 0; row < solve_cells.size(); row++) {
|
|
int l_pos = legal_pos(solve_cells.at(row));
|
|
int c_pos = cell_pos(solve_cells.at(row));
|
|
|
|
double weight =
|
|
alpha * iter /
|
|
std::max<double>(1, (yaxis ? cfg.hpwl_scale_y : cfg.hpwl_scale_x) * std::abs(l_pos - c_pos));
|
|
// Add an arc from legalised to current position
|
|
es.add_coeff(row, row, weight);
|
|
es.add_rhs(row, weight * l_pos);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Build the system of equations for either X or Y
|
|
void solve_equations(EquationSystem<double> &es, bool yaxis)
|
|
{
|
|
// 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;
|
|
std::transform(solve_cells.begin(), solve_cells.end(), std::back_inserter(vals), cell_pos);
|
|
es.solve(vals, cfg.solverTolerance);
|
|
for (size_t i = 0; i < vals.size(); i++)
|
|
if (yaxis) {
|
|
cell_locs.at(solve_cells.at(i)->name).rawy = vals.at(i);
|
|
cell_locs.at(solve_cells.at(i)->name).y = std::min(max_y, std::max(0, int(vals.at(i))));
|
|
if (solve_cells.at(i)->region != nullptr)
|
|
cell_locs.at(solve_cells.at(i)->name).y =
|
|
limit_to_reg(solve_cells.at(i)->region, cell_locs.at(solve_cells.at(i)->name).y, true);
|
|
} else {
|
|
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))));
|
|
if (solve_cells.at(i)->region != nullptr)
|
|
cell_locs.at(solve_cells.at(i)->name).x =
|
|
limit_to_reg(solve_cells.at(i)->region, cell_locs.at(solve_cells.at(i)->name).x, false);
|
|
}
|
|
}
|
|
|
|
// Compute HPWL
|
|
wirelen_t total_hpwl()
|
|
{
|
|
wirelen_t hpwl = 0;
|
|
for (auto net : sorted(ctx->nets)) {
|
|
NetInfo *ni = net.second;
|
|
if (ni->driver.cell == nullptr)
|
|
continue;
|
|
CellLocation &drvloc = cell_locs.at(ni->driver.cell->name);
|
|
if (drvloc.global)
|
|
continue;
|
|
int xmin = drvloc.x, xmax = drvloc.x, ymin = drvloc.y, ymax = drvloc.y;
|
|
for (auto &user : ni->users) {
|
|
CellLocation &usrloc = cell_locs.at(user.cell->name);
|
|
xmin = std::min(xmin, usrloc.x);
|
|
xmax = std::max(xmax, usrloc.x);
|
|
ymin = std::min(ymin, usrloc.y);
|
|
ymax = std::max(ymax, usrloc.y);
|
|
}
|
|
hpwl += cfg.hpwl_scale_x * (xmax - xmin) + cfg.hpwl_scale_y * (ymax - ymin);
|
|
}
|
|
return hpwl;
|
|
}
|
|
|
|
// Strict placement legalisation, performed after the initial HeAP spreading
|
|
void legalise_placement_strict(bool require_validity = false)
|
|
{
|
|
auto startt = std::chrono::high_resolution_clock::now();
|
|
|
|
// Unbind all cells placed in this solution
|
|
for (auto cell : sorted(ctx->cells)) {
|
|
CellInfo *ci = cell.second;
|
|
if (ci->bel != BelId() && (ci->udata != dont_solve ||
|
|
(chain_root.count(ci->name) && chain_root.at(ci->name)->udata != dont_solve)))
|
|
ctx->unbindBel(ci->bel);
|
|
}
|
|
|
|
// At the moment we don't follow the full HeAP algorithm using cuts for legalisation, instead using
|
|
// the simple greedy largest-macro-first approach.
|
|
std::priority_queue<std::pair<int, IdString>> remaining;
|
|
for (auto cell : solve_cells) {
|
|
remaining.emplace(chain_size[cell->name], cell->name);
|
|
}
|
|
int ripup_radius = 2;
|
|
int total_iters = 0;
|
|
int total_iters_noreset = 0;
|
|
while (!remaining.empty()) {
|
|
auto top = remaining.top();
|
|
remaining.pop();
|
|
|
|
CellInfo *ci = ctx->cells.at(top.second).get();
|
|
// Was now placed, ignore
|
|
if (ci->bel != BelId())
|
|
continue;
|
|
// log_info(" Legalising %s (%s)\n", top.second.c_str(ctx), ci->type.c_str(ctx));
|
|
FastBels::FastBelsData *fb;
|
|
fast_bels.getBelsForCellType(ci->type, &fb);
|
|
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();
|
|
|
|
total_iters++;
|
|
total_iters_noreset++;
|
|
if (total_iters > int(solve_cells.size())) {
|
|
total_iters = 0;
|
|
ripup_radius = std::max(std::max(max_x, max_y), ripup_radius * 2);
|
|
}
|
|
|
|
if (total_iters_noreset > std::max(5000, 8 * int(ctx->cells.size()))) {
|
|
log_error("Unable to find legal placement for all cells, design is probably at utilisation limit.\n");
|
|
}
|
|
|
|
while (!placed) {
|
|
|
|
// Set a conservative timeout
|
|
if (iter > std::max(10000, 3 * int(ctx->cells.size())))
|
|
log_error("Unable to find legal placement for cell '%s', check constraints and utilisation.\n",
|
|
ctx->nameOf(ci));
|
|
|
|
// Determine a search radius around the solver location (which increases over time) that is clamped to
|
|
// the region constraint for the cell (if applicable)
|
|
int rx = radius, ry = radius;
|
|
|
|
if (ci->region != nullptr) {
|
|
rx = std::min(radius, (constraint_region_bounds[ci->region->name].x1 -
|
|
constraint_region_bounds[ci->region->name].x0) /
|
|
2 +
|
|
1);
|
|
ry = std::min(radius, (constraint_region_bounds[ci->region->name].y1 -
|
|
constraint_region_bounds[ci->region->name].y0) /
|
|
2 +
|
|
1);
|
|
}
|
|
|
|
// Pick a random X and Y location within our search radius
|
|
int nx = ctx->rng(2 * rx + 1) + std::max(cell_locs.at(ci->name).x - rx, 0);
|
|
int ny = ctx->rng(2 * ry + 1) + std::max(cell_locs.at(ci->name).y - ry, 0);
|
|
|
|
iter++;
|
|
iter_at_radius++;
|
|
if (iter >= (10 * (radius + 1))) {
|
|
// No luck yet, increase radius
|
|
radius = std::min(std::max(max_x, max_y), radius + 1);
|
|
while (radius < std::max(max_x, max_y)) {
|
|
// Keep increasing the radius until it will actually increase the number of cells we are
|
|
// checking (e.g. BRAM and DSP will not be in all cols/rows), so we don't waste effort
|
|
for (int x = std::max(0, cell_locs.at(ci->name).x - radius);
|
|
x <= std::min(max_x, cell_locs.at(ci->name).x + radius); x++) {
|
|
if (x >= int(fb->size()))
|
|
break;
|
|
for (int y = std::max(0, cell_locs.at(ci->name).y - radius);
|
|
y <= std::min(max_y, cell_locs.at(ci->name).y + radius); y++) {
|
|
if (y >= int(fb->at(x).size()))
|
|
break;
|
|
if (fb->at(x).at(y).size() > 0)
|
|
goto notempty;
|
|
}
|
|
}
|
|
radius = std::min(std::max(max_x, max_y), radius + 1);
|
|
}
|
|
notempty:
|
|
iter_at_radius = 0;
|
|
iter = 0;
|
|
}
|
|
// If our randomly chosen cooridnate is out of bounds; or points to a tile with no relevant bels; ignore
|
|
// it
|
|
if (nx < 0 || nx > max_x)
|
|
continue;
|
|
if (ny < 0 || ny > max_y)
|
|
continue;
|
|
|
|
if (nx >= int(fb->size()))
|
|
continue;
|
|
if (ny >= int(fb->at(nx).size()))
|
|
continue;
|
|
if (fb->at(nx).at(ny).empty())
|
|
continue;
|
|
|
|
// The number of attempts to find a location to try
|
|
int need_to_explore = 2 * radius;
|
|
|
|
// If we have found at least one legal location; and made enough attempts; assume it's good enough and
|
|
// finish
|
|
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() && !ci->constr_abs_z) {
|
|
// The case where we have no relative constraints
|
|
for (auto sz : fb->at(nx).at(ny)) {
|
|
// Look through all bels in this tile; checking region constraint if applicable
|
|
if (!ci->testRegion(sz))
|
|
continue;
|
|
// Prefer available bels; unless we are dealing with a wide radius (e.g. difficult control sets)
|
|
// or occasionally trigger a tiebreaker
|
|
if (ctx->checkBelAvail(sz) || (radius > ripup_radius || ctx->rng(20000) < 10)) {
|
|
CellInfo *bound = ctx->getBoundBelCell(sz);
|
|
if (bound != nullptr) {
|
|
// Only rip up cells without constraints
|
|
if (bound->isConstrained())
|
|
continue;
|
|
ctx->unbindBel(bound->bel);
|
|
}
|
|
// Provisionally bind the bel
|
|
ctx->bindBel(sz, ci, STRENGTH_WEAK);
|
|
if (require_validity && !ctx->isBelLocationValid(sz)) {
|
|
// New location is not legal; unbind the cell (and rebind the cell we ripped up if
|
|
// applicable)
|
|
ctx->unbindBel(sz);
|
|
if (bound != nullptr)
|
|
ctx->bindBel(sz, bound, STRENGTH_WEAK);
|
|
} else if (iter_at_radius < need_to_explore) {
|
|
// It's legal, but we haven't tried enough locations yet
|
|
ctx->unbindBel(sz);
|
|
if (bound != nullptr)
|
|
ctx->bindBel(sz, bound, STRENGTH_WEAK);
|
|
int input_len = 0;
|
|
// Compute a fast input wirelength metric at this bel; and save if better than our last
|
|
// try
|
|
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 {
|
|
// It's legal, and we've tried enough. Finish.
|
|
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;
|
|
placed = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
// We do have relative constraints
|
|
for (auto sz : fb->at(nx).at(ny)) {
|
|
Loc loc = ctx->getBelLocation(sz);
|
|
// Check that the absolute-z constraint is satisfied if applicable
|
|
if (ci->constr_abs_z && loc.z != ci->constr_z)
|
|
continue;
|
|
// List of cells and their destination
|
|
std::vector<std::pair<CellInfo *, BelId>> targets;
|
|
// List of bels we placed things at; and the cell that was there before if applicable
|
|
std::vector<std::pair<BelId, CellInfo *>> swaps_made;
|
|
// List of (cell, new location) pairs to check
|
|
std::queue<std::pair<CellInfo *, Loc>> visit;
|
|
// FIXME: this approach of having a visit queue is designed to deal with recursively chained
|
|
// cells. But is this a case we really want to care about given the complexity it adds? Start by
|
|
// considering the root cell at the root location
|
|
visit.emplace(ci, loc);
|
|
while (!visit.empty()) {
|
|
CellInfo *vc = visit.front().first;
|
|
NPNR_ASSERT(vc->bel == BelId());
|
|
Loc ploc = visit.front().second;
|
|
visit.pop();
|
|
// Get the bel we're going to place this cell at
|
|
BelId target = ctx->getBelByLocation(ploc);
|
|
// Check it satisfies the region constraint if applicable
|
|
if (!vc->testRegion(target))
|
|
goto fail;
|
|
CellInfo *bound;
|
|
// Check that the target bel exists and is of a suitable type
|
|
if (target == BelId() || !ctx->isValidBelForCellType(vc->type, target))
|
|
goto fail;
|
|
bound = ctx->getBoundBelCell(target);
|
|
// Chains cannot overlap; so if we have to ripup a cell make sure it isn't part of a chain
|
|
if (bound != nullptr)
|
|
if (bound->isConstrained() || bound->belStrength > STRENGTH_WEAK)
|
|
goto fail;
|
|
targets.emplace_back(vc, target);
|
|
for (auto child : vc->constr_children) {
|
|
// For all the constrained children; compute the location we need to place them at and
|
|
// add them to the queue
|
|
visit.emplace(child, child->getConstrainedLoc(ploc));
|
|
}
|
|
}
|
|
// Actually perform the move; keeping track of the moves we make so we can revert them if needed
|
|
for (auto &target : targets) {
|
|
CellInfo *bound = ctx->getBoundBelCell(target.second);
|
|
if (bound != nullptr)
|
|
ctx->unbindBel(target.second);
|
|
ctx->bindBel(target.second, target.first, STRENGTH_STRONG);
|
|
swaps_made.emplace_back(target.second, bound);
|
|
}
|
|
// Check that the move we have made is legal
|
|
for (auto &sm : swaps_made) {
|
|
if (!ctx->isBelLocationValid(sm.first))
|
|
goto fail;
|
|
}
|
|
|
|
if (false) {
|
|
fail:
|
|
// If the move turned out to be illegal; revert all the moves we made
|
|
for (auto &swap : swaps_made) {
|
|
ctx->unbindBel(swap.first);
|
|
if (swap.second != nullptr)
|
|
ctx->bindBel(swap.first, swap.second, STRENGTH_WEAK);
|
|
}
|
|
continue;
|
|
}
|
|
for (auto &target : targets) {
|
|
Loc loc = ctx->getBelLocation(target.second);
|
|
cell_locs[target.first->name].x = loc.x;
|
|
cell_locs[target.first->name].y = loc.y;
|
|
// log_info("%s %d %d %d\n", target.first->name.c_str(ctx), loc.x, loc.y, loc.z);
|
|
}
|
|
for (auto &swap : swaps_made) {
|
|
// Where we have ripped up cells; add them to the queue
|
|
if (swap.second != nullptr)
|
|
remaining.emplace(chain_size[swap.second->name], swap.second->name);
|
|
}
|
|
|
|
placed = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
auto endt = std::chrono::high_resolution_clock::now();
|
|
sl_time += std::chrono::duration<float>(endt - startt).count();
|
|
}
|
|
// Implementation of the cut-based spreading as described in the HeAP/SimPL papers
|
|
|
|
template <typename T> T limit_to_reg(Region *reg, T val, bool dir)
|
|
{
|
|
if (reg == nullptr)
|
|
return val;
|
|
int limit_low = dir ? constraint_region_bounds[reg->name].y0 : constraint_region_bounds[reg->name].x0;
|
|
int limit_high = dir ? constraint_region_bounds[reg->name].y1 : constraint_region_bounds[reg->name].x1;
|
|
return std::max<T>(std::min<T>(val, limit_high), limit_low);
|
|
}
|
|
|
|
struct ChainExtent
|
|
{
|
|
int x0, y0, x1, y1;
|
|
};
|
|
|
|
struct SpreaderRegion
|
|
{
|
|
int id;
|
|
int x0, y0, x1, y1;
|
|
std::vector<int> cells, bels;
|
|
bool overused(float beta) const
|
|
{
|
|
for (size_t t = 0; t < cells.size(); t++) {
|
|
if (bels.at(t) < 4) {
|
|
if (cells.at(t) > bels.at(t))
|
|
return true;
|
|
} else {
|
|
if (cells.at(t) > beta * bels.at(t))
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
};
|
|
|
|
class CutSpreader
|
|
{
|
|
public:
|
|
CutSpreader(HeAPPlacer *p, const std::unordered_set<BelBucketId> &buckets) : p(p), ctx(p->ctx), buckets(buckets)
|
|
{
|
|
// Get fast BELs data for all buckets being Cut/Spread.
|
|
size_t idx = 0;
|
|
for (BelBucketId bucket : sorted(buckets)) {
|
|
type_index[bucket] = idx;
|
|
FastBels::FastBelsData *fast_bels;
|
|
p->fast_bels.getBelsForBelBucket(bucket, &fast_bels);
|
|
fb.push_back(fast_bels);
|
|
++idx;
|
|
NPNR_ASSERT(fb.size() == idx);
|
|
}
|
|
}
|
|
static int seq;
|
|
void run()
|
|
{
|
|
auto startt = std::chrono::high_resolution_clock::now();
|
|
init();
|
|
find_overused_regions();
|
|
for (auto &r : regions) {
|
|
if (merged_regions.count(r.id))
|
|
continue;
|
|
#if 0
|
|
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);
|
|
#endif
|
|
}
|
|
expand_regions();
|
|
std::queue<std::pair<int, bool>> workqueue;
|
|
#if 0
|
|
std::vector<std::pair<double, double>> orig;
|
|
if (ctx->debug)
|
|
for (auto c : p->solve_cells)
|
|
orig.emplace_back(p->cell_locs[c->name].rawx, p->cell_locs[c->name].rawy);
|
|
#endif
|
|
for (auto &r : regions) {
|
|
if (merged_regions.count(r.id))
|
|
continue;
|
|
#if 0
|
|
for (auto t : sorted(beltype)) {
|
|
log_info("%s (%d, %d) |_> (%d, %d) %d/%d\n", t.c_str(ctx), r.x0, r.y0, r.x1, r.y1,
|
|
r.cells.at(type_index.at(t)), r.bels.at(type_index.at(t)));
|
|
}
|
|
|
|
#endif
|
|
workqueue.emplace(r.id, false);
|
|
}
|
|
while (!workqueue.empty()) {
|
|
auto front = workqueue.front();
|
|
workqueue.pop();
|
|
auto &r = regions.at(front.first);
|
|
if (std::all_of(r.cells.begin(), r.cells.end(), [](int x) { return x == 0; }))
|
|
continue;
|
|
auto res = cut_region(r, front.second);
|
|
if (res) {
|
|
workqueue.emplace(res->first, !front.second);
|
|
workqueue.emplace(res->second, !front.second);
|
|
} else {
|
|
// Try the other dir, in case stuck in one direction only
|
|
auto res2 = cut_region(r, !front.second);
|
|
if (res2) {
|
|
workqueue.emplace(res2->first, front.second);
|
|
workqueue.emplace(res2->second, front.second);
|
|
}
|
|
}
|
|
}
|
|
#if 0
|
|
if (ctx->debug) {
|
|
std::ofstream sp("spread" + std::to_string(seq) + ".csv");
|
|
for (size_t i = 0; i < p->solve_cells.size(); i++) {
|
|
auto &c = p->solve_cells.at(i);
|
|
if (c->type != beltype)
|
|
continue;
|
|
sp << orig.at(i).first << "," << orig.at(i).second << "," << p->cell_locs[c->name].rawx << "," << p->cell_locs[c->name].rawy << std::endl;
|
|
}
|
|
std::ofstream oc("cells" + std::to_string(seq) + ".csv");
|
|
for (size_t y = 0; y <= p->max_y; y++) {
|
|
for (size_t x = 0; x <= p->max_x; x++) {
|
|
oc << cells_at_location.at(x).at(y).size() << ", ";
|
|
}
|
|
oc << std::endl;
|
|
}
|
|
++seq;
|
|
}
|
|
#endif
|
|
auto endt = std::chrono::high_resolution_clock::now();
|
|
p->cl_time += std::chrono::duration<float>(endt - startt).count();
|
|
}
|
|
|
|
private:
|
|
HeAPPlacer *p;
|
|
Context *ctx;
|
|
std::unordered_set<BelBucketId> buckets;
|
|
std::unordered_map<BelBucketId, size_t> type_index;
|
|
std::vector<std::vector<std::vector<int>>> occupancy;
|
|
std::vector<std::vector<int>> groups;
|
|
std::vector<std::vector<ChainExtent>> chaines;
|
|
std::map<IdString, ChainExtent> cell_extents;
|
|
|
|
std::vector<std::vector<std::vector<std::vector<BelId>>> *> fb;
|
|
|
|
std::vector<SpreaderRegion> regions;
|
|
std::unordered_set<int> merged_regions;
|
|
// Cells at a location, sorted by real (not integer) x and y
|
|
std::vector<std::vector<std::vector<CellInfo *>>> cells_at_location;
|
|
|
|
int occ_at(int x, int y, int type) { return occupancy.at(x).at(y).at(type); }
|
|
|
|
int bels_at(int x, int y, int type)
|
|
{
|
|
if (x >= int(fb.at(type)->size()) || y >= int(fb.at(type)->at(x).size()))
|
|
return 0;
|
|
return int(fb.at(type)->at(x).at(y).size());
|
|
}
|
|
|
|
bool is_cell_fixed(const CellInfo &cell) const
|
|
{
|
|
return buckets.count(ctx->getBelBucketForCellType(cell.type)) == 0;
|
|
}
|
|
|
|
size_t cell_index(const CellInfo &cell) const { return type_index.at(ctx->getBelBucketForCellType(cell.type)); }
|
|
|
|
void init()
|
|
{
|
|
occupancy.resize(p->max_x + 1,
|
|
std::vector<std::vector<int>>(p->max_y + 1, std::vector<int>(buckets.size(), 0)));
|
|
groups.resize(p->max_x + 1, std::vector<int>(p->max_y + 1, -1));
|
|
chaines.resize(p->max_x + 1, std::vector<ChainExtent>(p->max_y + 1));
|
|
cells_at_location.resize(p->max_x + 1, std::vector<std::vector<CellInfo *>>(p->max_y + 1));
|
|
for (int x = 0; x <= p->max_x; x++)
|
|
for (int y = 0; y <= p->max_y; y++) {
|
|
for (int t = 0; t < int(buckets.size()); t++) {
|
|
occupancy.at(x).at(y).at(t) = 0;
|
|
}
|
|
groups.at(x).at(y) = -1;
|
|
chaines.at(x).at(y) = {x, y, x, y};
|
|
}
|
|
|
|
auto set_chain_ext = [&](IdString cell, int x, int y) {
|
|
if (!cell_extents.count(cell))
|
|
cell_extents[cell] = {x, y, x, y};
|
|
else {
|
|
cell_extents[cell].x0 = std::min(cell_extents[cell].x0, x);
|
|
cell_extents[cell].y0 = std::min(cell_extents[cell].y0, y);
|
|
cell_extents[cell].x1 = std::max(cell_extents[cell].x1, x);
|
|
cell_extents[cell].y1 = std::max(cell_extents[cell].y1, y);
|
|
}
|
|
};
|
|
|
|
for (auto &cell_loc : p->cell_locs) {
|
|
IdString cell_name = cell_loc.first;
|
|
const CellInfo &cell = *ctx->cells.at(cell_name);
|
|
const CellLocation &loc = cell_loc.second;
|
|
if (is_cell_fixed(cell)) {
|
|
continue;
|
|
}
|
|
|
|
if (cell.belStrength > STRENGTH_STRONG) {
|
|
continue;
|
|
}
|
|
|
|
occupancy.at(cell_loc.second.x).at(cell_loc.second.y).at(cell_index(cell))++;
|
|
|
|
// Compute ultimate extent of each chain root
|
|
if (p->chain_root.count(cell_name)) {
|
|
set_chain_ext(p->chain_root.at(cell_name)->name, loc.x, loc.y);
|
|
} else if (!ctx->cells.at(cell_name)->constr_children.empty()) {
|
|
set_chain_ext(cell_name, loc.x, loc.y);
|
|
}
|
|
}
|
|
|
|
for (auto &cell_loc : p->cell_locs) {
|
|
IdString cell_name = cell_loc.first;
|
|
const CellInfo &cell = *ctx->cells.at(cell_name);
|
|
const CellLocation &loc = cell_loc.second;
|
|
if (is_cell_fixed(cell)) {
|
|
continue;
|
|
}
|
|
|
|
if (cell.belStrength > STRENGTH_STRONG) {
|
|
continue;
|
|
}
|
|
|
|
// Transfer chain extents to the actual chains structure
|
|
ChainExtent *ce = nullptr;
|
|
if (p->chain_root.count(cell_name)) {
|
|
ce = &(cell_extents.at(p->chain_root.at(cell_name)->name));
|
|
} else if (!ctx->cells.at(cell_name)->constr_children.empty()) {
|
|
ce = &(cell_extents.at(cell_name));
|
|
}
|
|
|
|
if (ce) {
|
|
auto &lce = chaines.at(loc.x).at(loc.y);
|
|
lce.x0 = std::min(lce.x0, ce->x0);
|
|
lce.y0 = std::min(lce.y0, ce->y0);
|
|
lce.x1 = std::max(lce.x1, ce->x1);
|
|
lce.y1 = std::max(lce.y1, ce->y1);
|
|
}
|
|
}
|
|
|
|
for (auto cell : p->solve_cells) {
|
|
if (is_cell_fixed(*cell)) {
|
|
continue;
|
|
}
|
|
|
|
cells_at_location.at(p->cell_locs.at(cell->name).x).at(p->cell_locs.at(cell->name).y).push_back(cell);
|
|
}
|
|
}
|
|
|
|
void merge_regions(SpreaderRegion &merged, SpreaderRegion &mergee)
|
|
{
|
|
// Prevent grow_region from recursing while doing this
|
|
for (int x = mergee.x0; x <= mergee.x1; x++) {
|
|
for (int y = mergee.y0; y <= mergee.y1; y++) {
|
|
// log_info("%d %d\n", groups.at(x).at(y), mergee.id);
|
|
NPNR_ASSERT(groups.at(x).at(y) == mergee.id);
|
|
groups.at(x).at(y) = merged.id;
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
merged.cells.at(t) += occ_at(x, y, t);
|
|
merged.bels.at(t) += bels_at(x, y, t);
|
|
}
|
|
}
|
|
}
|
|
|
|
merged_regions.insert(mergee.id);
|
|
grow_region(merged, mergee.x0, mergee.y0, mergee.x1, mergee.y1);
|
|
}
|
|
|
|
void grow_region(SpreaderRegion &r, int x0, int y0, int x1, int y1, bool init = false)
|
|
{
|
|
// log_info("growing to (%d, %d) |_> (%d, %d)\n", x0, y0, x1, y1);
|
|
if ((x0 >= r.x0 && y0 >= r.y0 && x1 <= r.x1 && y1 <= r.y1) || init)
|
|
return;
|
|
int old_x0 = r.x0 + (init ? 1 : 0), old_y0 = r.y0, old_x1 = r.x1, old_y1 = r.y1;
|
|
r.x0 = std::min(r.x0, x0);
|
|
r.y0 = std::min(r.y0, y0);
|
|
r.x1 = std::max(r.x1, x1);
|
|
r.y1 = std::max(r.y1, y1);
|
|
|
|
auto process_location = [&](int x, int y) {
|
|
// Merge with any overlapping regions
|
|
if (groups.at(x).at(y) == -1) {
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
r.bels.at(t) += bels_at(x, y, t);
|
|
r.cells.at(t) += occ_at(x, y, t);
|
|
}
|
|
}
|
|
|
|
if (groups.at(x).at(y) != -1 && groups.at(x).at(y) != r.id)
|
|
merge_regions(r, regions.at(groups.at(x).at(y)));
|
|
groups.at(x).at(y) = r.id;
|
|
// Grow to cover any chains
|
|
auto &chaine = chaines.at(x).at(y);
|
|
grow_region(r, chaine.x0, chaine.y0, chaine.x1, chaine.y1);
|
|
};
|
|
for (int x = r.x0; x < old_x0; x++)
|
|
for (int y = r.y0; y <= r.y1; y++)
|
|
process_location(x, y);
|
|
for (int x = old_x1 + 1; x <= x1; x++)
|
|
for (int y = r.y0; y <= r.y1; y++)
|
|
process_location(x, y);
|
|
for (int y = r.y0; y < old_y0; y++)
|
|
for (int x = r.x0; x <= r.x1; x++)
|
|
process_location(x, y);
|
|
for (int y = old_y1 + 1; y <= r.y1; y++)
|
|
for (int x = r.x0; x <= r.x1; x++)
|
|
process_location(x, y);
|
|
}
|
|
|
|
void find_overused_regions()
|
|
{
|
|
for (int x = 0; x <= p->max_x; x++)
|
|
for (int y = 0; y <= p->max_y; y++) {
|
|
// Either already in a group, or not overutilised. Ignore
|
|
if (groups.at(x).at(y) != -1)
|
|
continue;
|
|
bool overutilised = false;
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
if (occ_at(x, y, t) > bels_at(x, y, t)) {
|
|
overutilised = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!overutilised)
|
|
continue;
|
|
// log_info("%d %d %d\n", x, y, occ_at(x, y));
|
|
int id = int(regions.size());
|
|
groups.at(x).at(y) = id;
|
|
SpreaderRegion reg;
|
|
reg.id = id;
|
|
reg.x0 = reg.x1 = x;
|
|
reg.y0 = reg.y1 = y;
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
reg.bels.push_back(bels_at(x, y, t));
|
|
reg.cells.push_back(occ_at(x, y, t));
|
|
}
|
|
// Make sure we cover carries, etc
|
|
grow_region(reg, reg.x0, reg.y0, reg.x1, reg.y1, true);
|
|
|
|
bool expanded = true;
|
|
while (expanded) {
|
|
expanded = false;
|
|
// Keep trying expansion in x and y, until we find no over-occupancy cells
|
|
// or hit grouped cells
|
|
|
|
// First try expanding in x
|
|
if (reg.x1 < p->max_x) {
|
|
bool over_occ_x = false;
|
|
for (int y1 = reg.y0; y1 <= reg.y1; y1++) {
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
if (occ_at(reg.x1 + 1, y1, t) > bels_at(reg.x1 + 1, y1, t)) {
|
|
over_occ_x = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (over_occ_x) {
|
|
expanded = true;
|
|
grow_region(reg, reg.x0, reg.y0, reg.x1 + 1, reg.y1);
|
|
}
|
|
}
|
|
|
|
if (reg.y1 < p->max_y) {
|
|
bool over_occ_y = false;
|
|
for (int x1 = reg.x0; x1 <= reg.x1; x1++) {
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
if (occ_at(x1, reg.y1 + 1, t) > bels_at(x1, reg.y1 + 1, t)) {
|
|
over_occ_y = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (over_occ_y) {
|
|
expanded = true;
|
|
grow_region(reg, reg.x0, reg.y0, reg.x1, reg.y1 + 1);
|
|
}
|
|
}
|
|
}
|
|
regions.push_back(reg);
|
|
}
|
|
}
|
|
|
|
void expand_regions()
|
|
{
|
|
std::queue<int> overu_regions;
|
|
float beta = p->cfg.beta;
|
|
for (auto &r : regions) {
|
|
if (!merged_regions.count(r.id) && r.overused(beta))
|
|
overu_regions.push(r.id);
|
|
}
|
|
while (!overu_regions.empty()) {
|
|
int rid = overu_regions.front();
|
|
overu_regions.pop();
|
|
if (merged_regions.count(rid))
|
|
continue;
|
|
auto ® = regions.at(rid);
|
|
while (reg.overused(beta)) {
|
|
bool changed = false;
|
|
for (int j = 0; j < p->cfg.spread_scale_x; j++) {
|
|
if (reg.x0 > 0) {
|
|
grow_region(reg, reg.x0 - 1, reg.y0, reg.x1, reg.y1);
|
|
changed = true;
|
|
if (!reg.overused(beta))
|
|
break;
|
|
}
|
|
if (reg.x1 < p->max_x) {
|
|
grow_region(reg, reg.x0, reg.y0, reg.x1 + 1, reg.y1);
|
|
changed = true;
|
|
if (!reg.overused(beta))
|
|
break;
|
|
}
|
|
}
|
|
for (int j = 0; j < p->cfg.spread_scale_y; j++) {
|
|
if (reg.y0 > 0) {
|
|
grow_region(reg, reg.x0, reg.y0 - 1, reg.x1, reg.y1);
|
|
changed = true;
|
|
if (!reg.overused(beta))
|
|
break;
|
|
}
|
|
if (reg.y1 < p->max_y) {
|
|
grow_region(reg, reg.x0, reg.y0, reg.x1, reg.y1 + 1);
|
|
changed = true;
|
|
if (!reg.overused(beta))
|
|
break;
|
|
}
|
|
}
|
|
if (!changed) {
|
|
for (auto bucket : sorted(buckets)) {
|
|
if (reg.cells > reg.bels) {
|
|
IdString bucket_name = ctx->getBelBucketName(bucket);
|
|
log_error("Failed to expand region (%d, %d) |_> (%d, %d) of %d %ss\n", reg.x0, reg.y0,
|
|
reg.x1, reg.y1, reg.cells.at(type_index.at(bucket)), bucket_name.c_str(ctx));
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Implementation of the recursive cut-based spreading as described in the HeAP paper
|
|
// Note we use "left" to mean "-x/-y" depending on dir and "right" to mean "+x/+y" depending on dir
|
|
|
|
std::vector<CellInfo *> cut_cells;
|
|
|
|
boost::optional<std::pair<int, int>> cut_region(SpreaderRegion &r, bool dir)
|
|
{
|
|
cut_cells.clear();
|
|
auto &cal = cells_at_location;
|
|
int total_cells = 0, total_bels = 0;
|
|
for (int x = r.x0; x <= r.x1; x++) {
|
|
for (int y = r.y0; y <= r.y1; y++) {
|
|
std::copy(cal.at(x).at(y).begin(), cal.at(x).at(y).end(), std::back_inserter(cut_cells));
|
|
for (size_t t = 0; t < buckets.size(); t++)
|
|
total_bels += bels_at(x, y, t);
|
|
}
|
|
}
|
|
for (auto &cell : cut_cells) {
|
|
total_cells += p->chain_size.count(cell->name) ? p->chain_size.at(cell->name) : 1;
|
|
}
|
|
std::sort(cut_cells.begin(), cut_cells.end(), [&](const CellInfo *a, const CellInfo *b) {
|
|
return dir ? (p->cell_locs.at(a->name).rawy < p->cell_locs.at(b->name).rawy)
|
|
: (p->cell_locs.at(a->name).rawx < p->cell_locs.at(b->name).rawx);
|
|
});
|
|
|
|
if (cut_cells.size() < 2)
|
|
return {};
|
|
// Find the cells midpoint, counting chains in terms of their total size - making the initial source cut
|
|
int pivot_cells = 0;
|
|
int pivot = 0;
|
|
for (auto &cell : cut_cells) {
|
|
pivot_cells += p->chain_size.count(cell->name) ? p->chain_size.at(cell->name) : 1;
|
|
if (pivot_cells >= total_cells / 2)
|
|
break;
|
|
pivot++;
|
|
}
|
|
if (pivot >= int(cut_cells.size())) {
|
|
pivot = int(cut_cells.size()) - 1;
|
|
}
|
|
// log_info("orig pivot %d/%d lc %d rc %d\n", pivot, int(cut_cells.size()), pivot_cells, total_cells -
|
|
// pivot_cells);
|
|
|
|
// Find the clearance required either side of the pivot
|
|
int clearance_l = 0, clearance_r = 0;
|
|
for (size_t i = 0; i < cut_cells.size(); i++) {
|
|
int size;
|
|
if (cell_extents.count(cut_cells.at(i)->name)) {
|
|
auto &ce = cell_extents.at(cut_cells.at(i)->name);
|
|
size = dir ? (ce.y1 - ce.y0 + 1) : (ce.x1 - ce.x0 + 1);
|
|
} else {
|
|
size = 1;
|
|
}
|
|
if (int(i) < pivot)
|
|
clearance_l = std::max(clearance_l, size);
|
|
else
|
|
clearance_r = std::max(clearance_r, size);
|
|
}
|
|
// Find the target cut that minimises difference in utilisation, whilst trying to ensure that all chains
|
|
// still fit
|
|
|
|
// First trim the boundaries of the region in the axis-of-interest, skipping any rows/cols without any
|
|
// bels of the appropriate type
|
|
int trimmed_l = dir ? r.y0 : r.x0, trimmed_r = dir ? r.y1 : r.x1;
|
|
while (trimmed_l < (dir ? r.y1 : r.x1)) {
|
|
bool have_bels = false;
|
|
for (int i = dir ? r.x0 : r.y0; i <= (dir ? r.x1 : r.y1); i++) {
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
if (bels_at(dir ? i : trimmed_l, dir ? trimmed_l : i, t) > 0) {
|
|
have_bels = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (have_bels)
|
|
break;
|
|
|
|
trimmed_l++;
|
|
}
|
|
while (trimmed_r > (dir ? r.y0 : r.x0)) {
|
|
bool have_bels = false;
|
|
for (int i = dir ? r.x0 : r.y0; i <= (dir ? r.x1 : r.y1); i++) {
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
if (bels_at(dir ? i : trimmed_r, dir ? trimmed_r : i, t) > 0) {
|
|
have_bels = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (have_bels)
|
|
break;
|
|
|
|
trimmed_r--;
|
|
}
|
|
// log_info("tl %d tr %d cl %d cr %d\n", trimmed_l, trimmed_r, clearance_l, clearance_r);
|
|
if ((trimmed_r - trimmed_l + 1) <= std::max(clearance_l, clearance_r))
|
|
return {};
|
|
// Now find the initial target cut that minimises utilisation imbalance, whilst
|
|
// meeting the clearance requirements for any large macros
|
|
std::vector<int> left_cells_v(buckets.size(), 0), right_cells_v(buckets.size(), 0);
|
|
std::vector<int> left_bels_v(buckets.size(), 0), right_bels_v(r.bels);
|
|
for (int i = 0; i <= pivot; i++)
|
|
left_cells_v.at(cell_index(*cut_cells.at(i))) +=
|
|
p->chain_size.count(cut_cells.at(i)->name) ? p->chain_size.at(cut_cells.at(i)->name) : 1;
|
|
for (int i = pivot + 1; i < int(cut_cells.size()); i++)
|
|
right_cells_v.at(cell_index(*cut_cells.at(i))) +=
|
|
p->chain_size.count(cut_cells.at(i)->name) ? p->chain_size.at(cut_cells.at(i)->name) : 1;
|
|
|
|
int best_tgt_cut = -1;
|
|
double best_deltaU = std::numeric_limits<double>::max();
|
|
// std::pair<int, int> target_cut_bels;
|
|
std::vector<int> slither_bels(buckets.size(), 0);
|
|
for (int i = trimmed_l; i <= trimmed_r; i++) {
|
|
for (size_t t = 0; t < buckets.size(); t++)
|
|
slither_bels.at(t) = 0;
|
|
for (int j = dir ? r.x0 : r.y0; j <= (dir ? r.x1 : r.y1); j++) {
|
|
for (size_t t = 0; t < buckets.size(); t++)
|
|
slither_bels.at(t) += dir ? bels_at(j, i, t) : bels_at(i, j, t);
|
|
}
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
left_bels_v.at(t) += slither_bels.at(t);
|
|
right_bels_v.at(t) -= slither_bels.at(t);
|
|
}
|
|
|
|
if (((i - trimmed_l) + 1) >= clearance_l && ((trimmed_r - i) + 1) >= clearance_r) {
|
|
// Solution is potentially valid
|
|
double aU = 0;
|
|
for (size_t t = 0; t < buckets.size(); t++)
|
|
aU += (left_cells_v.at(t) + right_cells_v.at(t)) *
|
|
std::abs(double(left_cells_v.at(t)) / double(std::max(left_bels_v.at(t), 1)) -
|
|
double(right_cells_v.at(t)) / double(std::max(right_bels_v.at(t), 1)));
|
|
if (aU < best_deltaU) {
|
|
best_deltaU = aU;
|
|
best_tgt_cut = i;
|
|
}
|
|
}
|
|
}
|
|
if (best_tgt_cut == -1)
|
|
return {};
|
|
// left_bels = target_cut_bels.first;
|
|
// right_bels = target_cut_bels.second;
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
left_bels_v.at(t) = 0;
|
|
right_bels_v.at(t) = 0;
|
|
}
|
|
for (int x = r.x0; x <= (dir ? r.x1 : best_tgt_cut); x++)
|
|
for (int y = r.y0; y <= (dir ? best_tgt_cut : r.y1); y++) {
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
left_bels_v.at(t) += bels_at(x, y, t);
|
|
}
|
|
}
|
|
for (int x = dir ? r.x0 : (best_tgt_cut + 1); x <= r.x1; x++)
|
|
for (int y = dir ? (best_tgt_cut + 1) : r.y0; y <= r.y1; y++) {
|
|
for (size_t t = 0; t < buckets.size(); t++) {
|
|
right_bels_v.at(t) += bels_at(x, y, t);
|
|
}
|
|
}
|
|
if (std::accumulate(left_bels_v.begin(), left_bels_v.end(), 0) == 0 ||
|
|
std::accumulate(right_bels_v.begin(), right_bels_v.end(), 0) == 0)
|
|
return {};
|
|
|
|
// Perturb the source cut to eliminate overutilisation
|
|
auto is_part_overutil = [&](bool r) {
|
|
double delta = 0;
|
|
for (size_t t = 0; t < left_cells_v.size(); t++) {
|
|
delta += double(left_cells_v.at(t)) / double(std::max(left_bels_v.at(t), 1)) -
|
|
double(right_cells_v.at(t)) / double(std::max(right_bels_v.at(t), 1));
|
|
}
|
|
return r ? delta < 0 : delta > 0;
|
|
};
|
|
while (pivot > 0 && is_part_overutil(false)) {
|
|
auto &move_cell = cut_cells.at(pivot);
|
|
int size = p->chain_size.count(move_cell->name) ? p->chain_size.at(move_cell->name) : 1;
|
|
left_cells_v.at(cell_index(*cut_cells.at(pivot))) -= size;
|
|
right_cells_v.at(cell_index(*cut_cells.at(pivot))) += size;
|
|
pivot--;
|
|
}
|
|
while (pivot < int(cut_cells.size()) - 1 && is_part_overutil(true)) {
|
|
auto &move_cell = cut_cells.at(pivot + 1);
|
|
int size = p->chain_size.count(move_cell->name) ? p->chain_size.at(move_cell->name) : 1;
|
|
left_cells_v.at(cell_index(*cut_cells.at(pivot))) += size;
|
|
right_cells_v.at(cell_index(*cut_cells.at(pivot))) -= size;
|
|
pivot++;
|
|
}
|
|
|
|
// Split regions into bins, and then spread cells by linear interpolation within those bins
|
|
auto spread_binlerp = [&](int cells_start, int cells_end, double area_l, double area_r) {
|
|
int N = cells_end - cells_start;
|
|
if (N <= 2) {
|
|
for (int i = cells_start; i < cells_end; i++) {
|
|
auto &pos = dir ? p->cell_locs.at(cut_cells.at(i)->name).rawy
|
|
: p->cell_locs.at(cut_cells.at(i)->name).rawx;
|
|
pos = area_l + i * ((area_r - area_l) / N);
|
|
}
|
|
return;
|
|
}
|
|
// Split region into up to 10 (K) bins
|
|
int K = std::min<int>(N, 10);
|
|
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, area_l + ((area_r - area_l + 0.99) * i) / K);
|
|
bin_bounds.emplace_back(cells_end, area_r + 0.99);
|
|
for (int i = 0; i < K; i++) {
|
|
auto &bl = bin_bounds.at(i), br = bin_bounds.at(i + 1);
|
|
double orig_left = dir ? p->cell_locs.at(cut_cells.at(bl.first)->name).rawy
|
|
: 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) / std::max(0.00001, orig_right - orig_left);
|
|
for (int j = bl.first; j < br.first; j++) {
|
|
Region *cr = cut_cells.at(j)->region;
|
|
if (cr != nullptr) {
|
|
// Limit spreading bounds to constraint region; if applicable
|
|
double brsc = p->limit_to_reg(cr, br.second, dir);
|
|
double blsc = p->limit_to_reg(cr, bl.second, dir);
|
|
double mr = (brsc - blsc) / std::max(0.00001, orig_right - orig_left);
|
|
auto &pos = dir ? p->cell_locs.at(cut_cells.at(j)->name).rawy
|
|
: p->cell_locs.at(cut_cells.at(j)->name).rawx;
|
|
NPNR_ASSERT(pos >= orig_left && pos <= orig_right);
|
|
pos = blsc + mr * (pos - orig_left);
|
|
} else {
|
|
auto &pos = dir ? p->cell_locs.at(cut_cells.at(j)->name).rawy
|
|
: p->cell_locs.at(cut_cells.at(j)->name).rawx;
|
|
NPNR_ASSERT(pos >= orig_left && pos <= orig_right);
|
|
pos = bl.second + m * (pos - orig_left);
|
|
}
|
|
}
|
|
}
|
|
};
|
|
spread_binlerp(0, pivot + 1, trimmed_l, best_tgt_cut);
|
|
spread_binlerp(pivot + 1, int(cut_cells.size()), best_tgt_cut + 1, trimmed_r);
|
|
// Update various data structures
|
|
for (int x = r.x0; x <= r.x1; x++)
|
|
for (int y = r.y0; y <= r.y1; y++) {
|
|
cells_at_location.at(x).at(y).clear();
|
|
}
|
|
for (auto cell : cut_cells) {
|
|
auto &cl = p->cell_locs.at(cell->name);
|
|
cl.x = std::min(r.x1, std::max(r.x0, int(cl.rawx)));
|
|
cl.y = std::min(r.y1, std::max(r.y0, int(cl.rawy)));
|
|
cells_at_location.at(cl.x).at(cl.y).push_back(cell);
|
|
}
|
|
SpreaderRegion rl, rr;
|
|
rl.id = int(regions.size());
|
|
rl.x0 = r.x0;
|
|
rl.y0 = r.y0;
|
|
rl.x1 = dir ? r.x1 : best_tgt_cut;
|
|
rl.y1 = dir ? best_tgt_cut : r.y1;
|
|
rl.cells = left_cells_v;
|
|
rl.bels = left_bels_v;
|
|
rr.id = int(regions.size()) + 1;
|
|
rr.x0 = dir ? r.x0 : (best_tgt_cut + 1);
|
|
rr.y0 = dir ? (best_tgt_cut + 1) : r.y0;
|
|
rr.x1 = r.x1;
|
|
rr.y1 = r.y1;
|
|
rr.cells = right_cells_v;
|
|
rr.bels = right_bels_v;
|
|
regions.push_back(rl);
|
|
regions.push_back(rr);
|
|
for (int x = rl.x0; x <= rl.x1; x++)
|
|
for (int y = rl.y0; y <= rl.y1; y++)
|
|
groups.at(x).at(y) = rl.id;
|
|
for (int x = rr.x0; x <= rr.x1; x++)
|
|
for (int y = rr.y0; y <= rr.y1; y++)
|
|
groups.at(x).at(y) = rr.id;
|
|
return std::make_pair(rl.id, rr.id);
|
|
};
|
|
};
|
|
typedef decltype(CellInfo::udata) cell_udata_t;
|
|
cell_udata_t dont_solve = std::numeric_limits<cell_udata_t>::max();
|
|
};
|
|
int HeAPPlacer::CutSpreader::seq = 0;
|
|
|
|
bool placer_heap(Context *ctx, PlacerHeapCfg cfg) { return HeAPPlacer(ctx, cfg).place(); }
|
|
|
|
PlacerHeapCfg::PlacerHeapCfg(Context *ctx)
|
|
{
|
|
alpha = ctx->setting<float>("placerHeap/alpha");
|
|
beta = ctx->setting<float>("placerHeap/beta");
|
|
criticalityExponent = ctx->setting<int>("placerHeap/criticalityExponent");
|
|
timingWeight = ctx->setting<int>("placerHeap/timingWeight");
|
|
timing_driven = ctx->setting<bool>("timing_driven");
|
|
solverTolerance = 1e-5;
|
|
placeAllAtOnce = false;
|
|
|
|
hpwl_scale_x = 1;
|
|
hpwl_scale_y = 1;
|
|
spread_scale_x = 1;
|
|
spread_scale_y = 1;
|
|
}
|
|
|
|
NEXTPNR_NAMESPACE_END
|
|
|
|
#else
|
|
|
|
#include "log.h"
|
|
#include "nextpnr.h"
|
|
#include "placer_heap.h"
|
|
|
|
NEXTPNR_NAMESPACE_BEGIN
|
|
bool placer_heap(Context *ctx, PlacerHeapCfg cfg)
|
|
{
|
|
log_error("nextpnr was built without the HeAP placer\n");
|
|
return false;
|
|
}
|
|
|
|
PlacerHeapCfg::PlacerHeapCfg(Context *ctx) {}
|
|
|
|
NEXTPNR_NAMESPACE_END
|
|
|
|
#endif
|