diff --git a/common/kernel/command.cc b/common/kernel/command.cc index c548509f..65aa0299 100644 --- a/common/kernel/command.cc +++ b/common/kernel/command.cc @@ -189,6 +189,8 @@ po::options_description CommandHandler::getGeneralOptions() general.add_options()("placer-heap-critexp", po::value(), "placer heap criticality exponent (int, default: 2)"); general.add_options()("placer-heap-timingweight", po::value(), "placer heap timing weight (int, default: 10)"); + general.add_options()("placer-heap-cell-placement-timeout", po::value(), + "allow placer to attempt up to max(10000, total cells^2 / N) iterations to place a cell (int N, default: 8, 0 for no timeout)"); #if !defined(__wasm) general.add_options()("parallel-refine", "use new experimental parallelised engine for placement refinement"); @@ -328,6 +330,10 @@ void CommandHandler::setupContext(Context *ctx) if (vm.count("placer-heap-timingweight")) ctx->settings[ctx->id("placerHeap/timingWeight")] = std::to_string(vm["placer-heap-timingweight"].as()); + if (vm.count("placer-heap-cell-placement-timeout")) + ctx->settings[ctx->id("placerHeap/cellPlacementTimeout")] = + std::to_string(std::max(0, vm["placer-heap-cell-placement-timeout"].as())); + if (vm.count("parallel-refine")) ctx->settings[ctx->id("placerHeap/parallelRefine")] = true; diff --git a/common/place/placer_heap.cc b/common/place/placer_heap.cc index 339b88e7..7fa27206 100644 --- a/common/place/placer_heap.cc +++ b/common/place/placer_heap.cc @@ -218,7 +218,10 @@ class HeAPPlacer heap_runs.push_back(all_buckets); // The main HeAP placer loop - log_info("Running main analytical placer.\n"); + if (cfg.cell_placement_timeout > 0) + log_info("Running main analytical placer, max placement attempts per cell = %d.\n", cfg.cell_placement_timeout); + else + log_info("Running main analytical placer.\n"); while (stalled < 5 && (solved_hpwl <= legal_hpwl * 0.8)) { // Alternate between particular bel types and all bels for (auto &run : heap_runs) { @@ -862,6 +865,7 @@ class HeAPPlacer int radius = 0; int iter = 0; int iter_at_radius = 0; + int total_iters_for_cell = 0; bool placed = false; BelId bestBel; int best_inp_len = std::numeric_limits::max(); @@ -878,11 +882,9 @@ class HeAPPlacer } 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)); + if (cfg.cell_placement_timeout > 0 && total_iters_for_cell > cfg.cell_placement_timeout) + log_error("Unable to find legal placement for cell '%s' after %d attempts, check constraints and utilisation. Use `--placer-heap-cell-placement-timeout` to change the number of attempts.\n", + ctx->nameOf(ci), total_iters_for_cell); // Determine a search radius around the solver location (which increases over time) that is clamped to // the region constraint for the cell (if applicable) @@ -1084,6 +1086,8 @@ class HeAPPlacer break; } } + + total_iters_for_cell++; } } auto endt = std::chrono::high_resolution_clock::now(); @@ -1814,6 +1818,15 @@ PlacerHeapCfg::PlacerHeapCfg(Context *ctx) solverTolerance = 1e-5; placeAllAtOnce = false; + int timeout_divisor = ctx->setting("placerHeap/cellPlacementTimeout", 8); + if (timeout_divisor > 0) { + // Set a conservative default. This is a rather large number and could probably + // be shaved down, but for now it will keep the process from running indefinite. + cell_placement_timeout = std::max(10000, (int(ctx->cells.size()) * int(ctx->cells.size()) / timeout_divisor)); + } else { + cell_placement_timeout = 0; + } + hpwl_scale_x = 1; hpwl_scale_y = 1; spread_scale_x = 1; diff --git a/common/place/placer_heap.h b/common/place/placer_heap.h index 9c62869e..e554a8e0 100644 --- a/common/place/placer_heap.h +++ b/common/place/placer_heap.h @@ -42,6 +42,7 @@ struct PlacerHeapCfg float solverTolerance; bool placeAllAtOnce; bool parallelRefine; + int cell_placement_timeout; int hpwl_scale_x, hpwl_scale_y; int spread_scale_x, spread_scale_y;