From 539c5eeb0f472ee6c92f4204552a08ea4f2ec197 Mon Sep 17 00:00:00 2001 From: Clifford Wolf Date: Sun, 20 Sep 2015 18:28:46 +0200 Subject: Added "qwp" command --- passes/cmds/qwp.cc | 585 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 585 insertions(+) create mode 100644 passes/cmds/qwp.cc (limited to 'passes/cmds/qwp.cc') diff --git a/passes/cmds/qwp.cc b/passes/cmds/qwp.cc new file mode 100644 index 000000000..86a7a5556 --- /dev/null +++ b/passes/cmds/qwp.cc @@ -0,0 +1,585 @@ +/* + * yosys -- Yosys Open SYnthesis Suite + * + * Copyright (C) 2012 Clifford Wolf + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + */ + +#include "kernel/yosys.h" +#include "kernel/sigtools.h" + +#undef LOG_MATRICES +#undef PYPLOT_EDGES + +USING_YOSYS_NAMESPACE +PRIVATE_NAMESPACE_BEGIN + +static uint32_t xorshift32_state; + +static double xorshift32() +{ + xorshift32_state ^= xorshift32_state << 13; + xorshift32_state ^= xorshift32_state >> 17; + xorshift32_state ^= xorshift32_state << 5; + return (xorshift32_state % 1000000) / 1e6; +} + +struct QwpConfig +{ + bool ltr; + bool alpha; + double grid; + + QwpConfig() { + ltr = false; + alpha = false; + grid = 1.0 / 16; + } +}; + +struct QwpWorker +{ + const QwpConfig &config; + Module *module; + char direction; + + struct Node { + Cell *cell; + bool tied, alt_tied; + + // pos = position in current direction + // alt_pos = position in the other direction + double pos, alt_pos; + + Node() { + cell = nullptr; + tied = false; + pos = xorshift32(); + alt_tied = false; + alt_pos = xorshift32(); + } + + void tie(double v) { + tied = true; + pos = v; + } + + void alt_tie(double v) { + alt_tied = true; + alt_pos = v; + } + + void swap_alt() { + std::swap(tied, alt_tied); + std::swap(pos, alt_pos); + } + + void proj_left(double midpos) { + cell = nullptr; + tie(pos > midpos ? midpos : pos); + } + + void proj_right(double midpos) { + cell = nullptr; + tie(pos < midpos ? midpos : pos); + } + }; + + vector nodes; + dict, double> edges; + dict cell_to_node; + + QwpWorker(const QwpConfig &config, Module *module, char direction = 'x') : config(config), module(module), direction(direction) + { + log_assert(direction == 'x' || direction == 'y'); + } + + void load_module() + { + log_assert(direction == 'x'); + + SigMap sigmap(module); + dict> bits_to_nodes; + + if (config.ltr || config.alpha) + { + dict alpha_inputs, alpha_outputs; + + if (config.alpha) + { + dict alpha_order; + + for (auto wire : module->wires()) { + if (wire->port_input || wire->port_output) + alpha_order[wire->name.str()] = wire; + } + + alpha_order.sort(); + + for (auto &it : alpha_order) { + if (it.second->port_input) { + int idx = GetSize(alpha_inputs); + alpha_inputs[it.second] = idx + 0.5; + } + if (it.second->port_output) { + int idx = GetSize(alpha_outputs); + alpha_outputs[it.second] = idx + 0.5; + } + } + } + + for (auto wire : module->wires()) + { + if (!wire->port_input && !wire->port_output) + continue; + + int idx = GetSize(nodes); + nodes.push_back(Node()); + + if (config.ltr) { + if (wire->port_input) + nodes[idx].tie(0.0); + else + nodes[idx].tie(1.0); + } + + if (config.alpha) { + if (wire->port_input) + nodes[idx].alt_tie(alpha_inputs.at(wire) / GetSize(alpha_inputs)); + else + nodes[idx].alt_tie(alpha_outputs.at(wire) / GetSize(alpha_outputs)); + } + + for (auto bit : sigmap(wire)) + bits_to_nodes[bit].insert(idx); + } + } + + for (auto cell : module->selected_cells()) + { + log_assert(cell_to_node.count(cell) == 0); + int idx = GetSize(nodes); + nodes.push_back(Node()); + + cell_to_node[cell] = GetSize(nodes); + nodes[idx].cell = cell; + + for (auto &conn : cell->connections()) + for (auto bit : sigmap(conn.second)) + bits_to_nodes[bit].insert(idx); + } + + for (auto &it : bits_to_nodes) + { + if (GetSize(it.second) > 100) + continue; + + for (int idx1 : it.second) + for (int idx2 : it.second) + if (idx1 < idx2) + edges[pair(idx1, idx2)] += 1.0 / GetSize(it.second); + } + } + + void solve() + { + int observation_matrix_m = GetSize(edges) + GetSize(nodes); + int observation_matrix_n = GetSize(nodes); + + // Column-major order + vector observation_matrix(observation_matrix_m * observation_matrix_n); + vector observation_rhs_vector(observation_matrix_m); + + int i = 0; + for (auto &edge : edges) { + int idx1 = edge.first.first; + int idx2 = edge.first.second; + double weight = edge.second * (1.0 + xorshift32() * 1e-3); + observation_matrix[i + observation_matrix_m*idx1] = weight; + observation_matrix[i + observation_matrix_m*idx2] = -weight; + i++; + } + + int j = 0; + for (auto &node : nodes) { + double weight = 1e-6; + if (node.tied) weight = 1e3; + weight *= (1.0 + xorshift32() * 1e-3); + observation_matrix[i + observation_matrix_m*j] = weight; + observation_rhs_vector[i] = node.pos * weight; + i++, j++; + } + +#ifdef LOG_MATRICES + log("----\n"); + for (int i = 0; i < observation_matrix_m; i++) { + for (int j = 0; j < observation_matrix_n; j++) + log(" %10.2e", observation_matrix[i + observation_matrix_m*j]); + log(" |%9.2e\n", observation_rhs_vector[i]); + } +#endif + + // A := observation_matrix + // y := observation_rhs_vector + // + // AA = A' * A + // Ay = A' * y + // + // M := [AA Ay] + + // Row major order + vector M(observation_matrix_n * (observation_matrix_n+1)); + int N = observation_matrix_n; + + for (int i = 0; i < N; i++) + for (int j = 0; j < N; j++) { + double sum = 0; + for (int k = 0; k < observation_matrix_m; k++) + sum += observation_matrix[k + observation_matrix_m*i] * observation_matrix[k + observation_matrix_m*j]; + M[(N+1)*i + j] = sum; + } + + for (int i = 0; i < N; i++) { + double sum = 0; + for (int k = 0; k < observation_matrix_m; k++) + sum += observation_matrix[k + observation_matrix_m*i] * observation_rhs_vector[k]; + M[(N+1)*i + N] = sum; + } + +#ifdef LOG_MATRICES + log("\n"); + for (int i = 0; i < N; i++) { + for (int j = 0; j < N+1; j++) + log(" %10.2e", M[(N+1)*i + j]); + log("\n"); + } +#endif + + // Solve "AA*x = Ay" + // (least squares fit for "A*x = y") + // + // Using gaussian elimination (no pivoting) to get M := [Id x] + + // eliminate to upper triangular matrix + for (int i = 0; i < N; i++) + { + // normalize row + for (int j = i+1; j < N+1; j++) + M[(N+1)*i + j] /= M[(N+1)*i + i]; + M[(N+1)*i + i] = 1.0; + + // elimination + for (int j = i+1; j < N; j++) { + double d = M[(N+1)*j + i]; + for (int k = 0; k < N+1; k++) + if (k > i) + M[(N+1)*j + k] -= d*M[(N+1)*i + k]; + else + M[(N+1)*j + k] = 0.0; + } + } + + // back substitution + for (int i = N-1; i >= 0; i--) + for (int j = i+1; j < N; j++) + { + M[(N+1)*i + N] -= M[(N+1)*i + j] * M[(N+1)*j + N]; + M[(N+1)*i + j] = 0.0; + } + +#ifdef LOG_MATRICES + log("\n"); + for (int i = 0; i < N; i++) { + for (int j = 0; j < N+1; j++) + log(" %10.2e", M[(N+1)*i + j]); + log("\n"); + } +#endif + + // update node positions + for (int i = 0; i < N; i++) + if (!nodes[i].tied) + nodes[i].pos = M[(N+1)*i + N]; + } + + void log_cell_coordinates(int indent, bool log_all_nodes = false) + { + for (auto &node : nodes) + { + if (node.cell == nullptr && !log_all_nodes) + continue; + + for (int i = 0; i < indent; i++) + log(" "); + + if (direction == 'x') + log("X=%.2f, Y=%.2f", node.pos, node.alt_pos); + else + log("X=%.2f, Y=%.2f", node.alt_pos, node.pos); + + if (node.tied) + log(" [%c-tied]", direction); + + if (node.alt_tied) + log(" [%c-tied]", direction == 'x' ? 'y' : 'x'); + + if (node.cell != nullptr) + log(" %s (%s)", log_id(node.cell), log_id(node.cell->type)); + else + log(" (none)"); + + log("\n"); + } + } + + void run_worker(int indent, double midpos, double radius, double alt_midpos, double alt_radius) + { + int count_cells = 0; + + for (auto &node : nodes) + if (node.cell != nullptr) + count_cells++; + + for (int i = 0; i < indent; i++) + log(" "); + + if (direction == 'x') + log("x-qwp on X=%.2f:%.2f, Y=%.2f:%.2f with %d cells, %d nodes, and %d edges.\n", + midpos - radius, midpos + radius, alt_midpos - alt_radius, alt_midpos + alt_radius, + count_cells, GetSize(nodes), GetSize(edges)); + else + log("y-qwp on X=%.2f:%.2f, Y=%.2f:%.2f with %d cells, %d nodes, and %d edges.\n", + alt_midpos - alt_radius, alt_midpos + alt_radius, midpos - radius, midpos + radius, + count_cells, GetSize(nodes), GetSize(edges)); + + solve(); + + for (auto &node : nodes) { + log_assert(node.pos + 0.1 >= midpos - radius); + log_assert(node.pos - 0.1 <= midpos + radius); + log_assert(node.alt_pos + 0.1 >= alt_midpos - alt_radius); + log_assert(node.alt_pos - 0.1 <= alt_midpos + alt_radius); + } + + if (2*radius <= config.grid && 2*alt_radius <= config.grid) { + log_cell_coordinates(indent + 1); + return; + } + + // detect median position + + vector> sorted_pos; + for (int i = 0; i < GetSize(nodes); i++) + if (nodes[i].cell != nullptr) + sorted_pos.push_back(pair(nodes[i].pos, i)); + + if (GetSize(sorted_pos) < 2) { + log_cell_coordinates(indent + 1); + return; + } + + std::sort(sorted_pos.begin(), sorted_pos.end()); + + // create child workers + + char child_direction = direction == 'x' ? 'y' : 'x'; + + QwpWorker left_worker(config, module, child_direction); + QwpWorker right_worker(config, module, child_direction); + + // duplicate nodes into child workers + + dict left_nodes, right_nodes; + + for (int k = 0; k < GetSize(sorted_pos); k++) + { + int i = sorted_pos[k].second; + + if (k < GetSize(sorted_pos) / 2) { + left_nodes[i] = GetSize(left_worker.nodes); + left_worker.nodes.push_back(nodes[i]); + if (left_worker.nodes.back().pos > midpos) + left_worker.nodes.back().pos = midpos; + left_worker.nodes.back().swap_alt(); + } else { + right_nodes[i] = GetSize(right_worker.nodes); + right_worker.nodes.push_back(nodes[i]); + if (right_worker.nodes.back().pos < midpos) + right_worker.nodes.back().pos = midpos; + right_worker.nodes.back().swap_alt(); + } + } + + // duplicate edges into child workers, project nodes as needed + + for (auto &edge : edges) + { + int idx1 = edge.first.first; + int idx2 = edge.first.second; + double weight = edge.second; + + if (nodes[idx1].cell == nullptr && nodes[idx2].cell == nullptr) + continue; + + int left_idx1 = left_nodes.count(idx1) ? left_nodes.at(idx1) : -1; + int left_idx2 = left_nodes.count(idx2) ? left_nodes.at(idx2) : -1; + + int right_idx1 = right_nodes.count(idx1) ? right_nodes.at(idx1) : -1; + int right_idx2 = right_nodes.count(idx2) ? right_nodes.at(idx2) : -1; + + if (nodes[idx1].cell && left_idx1 >= 0 && left_idx2 < 0) { + left_idx2 = left_nodes[idx2] = GetSize(left_worker.nodes); + left_worker.nodes.push_back(nodes[idx2]); + left_worker.nodes.back().proj_left(midpos); + left_worker.nodes.back().swap_alt(); + } else + if (nodes[idx2].cell && left_idx2 >= 0 && left_idx1 < 0) { + left_idx1 = left_nodes[idx1] = GetSize(left_worker.nodes); + left_worker.nodes.push_back(nodes[idx1]); + left_worker.nodes.back().proj_left(midpos); + left_worker.nodes.back().swap_alt(); + } + + if (nodes[idx1].cell && right_idx1 >= 0 && right_idx2 < 0) { + right_idx2 = right_nodes[idx2] = GetSize(right_worker.nodes); + right_worker.nodes.push_back(nodes[idx2]); + right_worker.nodes.back().proj_right(midpos); + right_worker.nodes.back().swap_alt(); + } else + if (nodes[idx2].cell && right_idx2 >= 0 && right_idx1 < 0) { + right_idx1 = right_nodes[idx1] = GetSize(right_worker.nodes); + right_worker.nodes.push_back(nodes[idx1]); + right_worker.nodes.back().proj_right(midpos); + right_worker.nodes.back().swap_alt(); + } + + if (left_idx1 >= 0 && left_idx2 >= 0) + left_worker.edges[pair(left_idx1, left_idx2)] += weight; + + if (right_idx1 >= 0 && right_idx2 >= 0) + right_worker.edges[pair(right_idx1, right_idx2)] += weight; + } + + // run child workers + + left_worker.run_worker(indent+1, alt_midpos, alt_radius, midpos - radius/2, radius/2); + right_worker.run_worker(indent+1, alt_midpos, alt_radius, midpos + radius/2, radius/2); + + // re-integrate results + + for (auto &it : left_nodes) + if (left_worker.nodes[it.second].cell != nullptr) { + nodes[it.first].pos = left_worker.nodes[it.second].alt_pos; + nodes[it.first].alt_pos = left_worker.nodes[it.second].pos; + } + + for (auto &it : right_nodes) + if (right_worker.nodes[it.second].cell != nullptr) { + nodes[it.first].pos = right_worker.nodes[it.second].alt_pos; + nodes[it.first].alt_pos = right_worker.nodes[it.second].pos; + } + } + + void run() + { + log("Running qwp on module %s..\n", log_id(module)); + + load_module(); + run_worker(1, 0.5, 0.5, 0.5, 0.5); + + for (auto &node : nodes) + if (node.cell != nullptr) + node.cell->attributes["\\qwp_position"] = stringf("%f %f", node.pos, node.alt_pos); + } +}; + +struct QwpPass : public Pass { + QwpPass() : Pass("qwp", "quadratic wirelength placer") { } + virtual void help() + { + // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---| + log("\n"); + log(" qwp [options] [selection]\n"); + log("\n"); + log("This command runs quadratic wirelength placement on the selected modules and\n"); + log("annotates the cells in the design with 'qwp_position' attributes.\n"); + log("\n"); + log(" -ltr\n"); + log(" Add left-to-right constraints: constrain all inputs on the left border\n"); + log(" outputs to the right border.\n"); + log("\n"); + log(" -alpha\n"); + log(" Add constraints for inputs/outputs to be placed in alphanumerical\n"); + log(" order along the y-axis (top-to-bottom).\n"); + log("\n"); + log(" -grid N\n"); + log(" Number of grid divisions in x- and y-direction. (default=16)\n"); + log("\n"); + log("Note: This implementation of a quadratic wirelength placer uses unoptimized\n"); + log("dense matrix operations. It is only a toy-placer for small circuits.\n"); + log("\n"); + } + virtual void execute(std::vector args, RTLIL::Design *design) + { + QwpConfig config; + xorshift32_state = 123456789; + + log_header("Executing QWP pass (quadratic wirelength placer).\n"); + + size_t argidx; + for (argidx = 1; argidx < args.size(); argidx++) { + if (args[argidx] == "-ltr") { + config.ltr = true; + continue; + } + if (args[argidx] == "-alpha") { + config.alpha = true; + continue; + } + if (args[argidx] == "-grid" && argidx+1 < args.size()) { + config.grid = 1.0 / atoi(args[++argidx].c_str()); + continue; + } + break; + } + extra_args(args, argidx, design); + + for (auto module : design->selected_modules()) + { + QwpWorker worker(config, module); + worker.run(); + +#ifdef PYPLOT_EDGES + log("\n"); + log("plt.figure(figsize=(10, 10));\n"); + + for (auto &edge : worker.edges) { + log("plt.plot([%.2f, %.2f], [%.2f, %.2f], \"r-\");\n", + worker.nodes[edge.first.first].pos, + worker.nodes[edge.first.second].pos, + worker.nodes[edge.first.first].alt_pos, + worker.nodes[edge.first.second].alt_pos); + } + + for (auto &node : worker.nodes) { + const char *style = node.cell != nullptr ? "ko" : "ks"; + log("plt.plot([%.2f], [%.2f], \"%s\");\n", node.pos, node.alt_pos, style); + } +#endif + } + } +} QwpPass; + +PRIVATE_NAMESPACE_END -- cgit v1.2.3