diff options
| -rw-r--r-- | common/place_sa.cc | 38 | ||||
| -rw-r--r-- | ice40/cells.cc | 7 |
2 files changed, 31 insertions, 14 deletions
diff --git a/common/place_sa.cc b/common/place_sa.cc index 2a56b177..daa26147 100644 --- a/common/place_sa.cc +++ b/common/place_sa.cc @@ -50,7 +50,7 @@ static void place_initial(Context *ctx, CellInfo *cell) while (!all_placed) { BelId best_bel = BelId(); uint64_t best_score = std::numeric_limits<uint64_t>::max(), - best_ripup_score = std::numeric_limits<uint64_t>::max(); + best_ripup_score = std::numeric_limits<uint64_t>::max(); CellInfo *ripup_target = nullptr; BelId ripup_bel = BelId(); if (cell->bel != BelId()) { @@ -146,7 +146,8 @@ static float get_wirelength(Context *ctx, NetInfo *net) } // Attempt a SA position swap, return true on success or false on failure -static bool try_swap_position(Context *ctx, CellInfo *cell, BelId newBel, SAState &state) +static bool try_swap_position(Context *ctx, CellInfo *cell, BelId newBel, + SAState &state) { static std::unordered_set<NetInfo *> update; static std::vector<std::pair<NetInfo *, float>> new_lengths; @@ -204,7 +205,7 @@ static bool try_swap_position(Context *ctx, CellInfo *cell, BelId newBel, SAStat // SA acceptance criterea if (delta < 0 || (state.temp > 1e-6 && - (ctx->rng() / float(0x3fffffff)) <= std::exp(-delta / state.temp))) { + (ctx->rng() / float(0x3fffffff)) <= std::exp(-delta / state.temp))) { state.n_accept++; if (delta < 0) state.improved = true; @@ -237,8 +238,10 @@ BelId random_bel_for_cell(Context *ctx, CellInfo *cell, SAState &state) int x = 0, y = 0; ctx->estimatePosition(cell->bel, x, y); while (true) { - int nx = ctx->rng(2 * state.diameter + 1) + std::max(x - state.diameter, 0); - int ny = ctx->rng(2 * state.diameter + 1) + std::max(y - state.diameter, 0); + int nx = ctx->rng(2 * state.diameter + 1) + + std::max(x - state.diameter, 0); + int ny = ctx->rng(2 * state.diameter + 1) + + std::max(y - state.diameter, 0); int beltype_idx = state.bel_types.at(targetType); if (nx >= int(state.fast_bels.at(beltype_idx).size())) continue; @@ -289,9 +292,10 @@ bool place_design_sa(Context *ctx) visit_cells.push(cell); } } - log_info("place_constraints placed %d\n", int(placed_cells)); - std::vector<CellInfo *> autoplaced; + log_info("Placed %d cells based on constraints.\n", int(placed_cells)); + // Sort to-place cells for deterministic initial placement + std::vector<CellInfo *> autoplaced; for (auto cell : ctx->cells) { CellInfo *ci = cell.second; if (ci->bel == BelId()) { @@ -300,11 +304,18 @@ bool place_design_sa(Context *ctx) } std::sort(autoplaced.begin(), autoplaced.end(), [](CellInfo *a, CellInfo *b) { return a->name < b->name; }); + ctx->shuffle(autoplaced); + // Place cells randomly initially + log_info("Creating initial placement for remaining %d cells.\n", + int(autoplaced.size())); for (auto cell : autoplaced) { place_initial(ctx, cell); placed_cells++; } + + log_info("Running simulated annealing placer.\n"); + // Build up a fast position/type to Bel lookup table int max_x = 0, max_y = 0; int bel_types = 0; @@ -330,6 +341,7 @@ bool place_design_sa(Context *ctx) state.fast_bels.at(type_idx).at(x).at(y).push_back(bel); } state.diameter = std::max(max_x, max_y) + 1; + // Calculate wirelength after initial placement state.curr_wirelength = 0; for (auto net : ctx->nets) { @@ -347,9 +359,9 @@ bool place_design_sa(Context *ctx) state.n_move = state.n_accept = 0; state.improved = false; - if (iter % 5 == 0) - log(" at iteration #%d: temp = %f, wire length = %f\n", iter, - state.temp, state.curr_wirelength); + if (iter % 5 == 0 || iter == 1) + log_info(" at iteration #%d: temp = %f, wire length = %f\n", iter, + state.temp, state.curr_wirelength); for (int m = 0; m < 15; ++m) { // Loop through all automatically placed cells @@ -369,8 +381,12 @@ bool place_design_sa(Context *ctx) } else ++n_no_progress; - if (state.temp <= 1e-3 && n_no_progress >= 5) + if (state.temp <= 1e-3 && n_no_progress >= 5) { + if (iter % 5 != 0) + log_info(" at iteration #%d: temp = %f, wire length = %f\n", + iter, state.temp, state.curr_wirelength); break; + } double Raccept = (double)state.n_accept / (double)state.n_move; diff --git a/ice40/cells.cc b/ice40/cells.cc index 582e5c14..c2bc4609 100644 --- a/ice40/cells.cc +++ b/ice40/cells.cc @@ -211,9 +211,10 @@ void nxio_to_sb(Context *ctx, CellInfo *nxio, CellInfo *sbio) replace_port(tbuf, "E", sbio, "OUTPUT_ENABLE"); ctx->nets.erase(donet->name); if (!donet->users.empty()) - log_error("unsupported tristate IO pattern for IO buffer '%s', " - "instantiate SB_IO manually to ensure correct behaviour\n", - nxio->name.c_str(ctx)); + log_error( + "unsupported tristate IO pattern for IO buffer '%s', " + "instantiate SB_IO manually to ensure correct behaviour\n", + nxio->name.c_str(ctx)); ctx->cells.erase(tbuf->name); } } |