--- /dev/null
+/*
+ * yosys -- Yosys Open SYnthesis Suite
+ *
+ * Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
+ *
+ * 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<Node> nodes;
+ dict<pair<int, int>, double> edges;
+ dict<Cell*, int> 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<SigBit, pool<int>> bits_to_nodes;
+
+ if (config.ltr || config.alpha)
+ {
+ dict<Wire*, double> alpha_inputs, alpha_outputs;
+
+ if (config.alpha)
+ {
+ dict<string, Wire*> 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<int, int>(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<double> observation_matrix(observation_matrix_m * observation_matrix_n);
+ vector<double> 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<double> 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<pair<double, int>> sorted_pos;
+ for (int i = 0; i < GetSize(nodes); i++)
+ if (nodes[i].cell != nullptr)
+ sorted_pos.push_back(pair<double, int>(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<int, int> 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<int, int>(left_idx1, left_idx2)] += weight;
+
+ if (right_idx1 >= 0 && right_idx2 >= 0)
+ right_worker.edges[pair<int, int>(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<std::string> 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
projects / yosys.git / commitdiff