+++ /dev/null
-/*
- * yosys -- Yosys Open SYnthesis Suite
- *
- * Copyright (C) 2012 Clifford Wolf <clifford@clifford.at>
- * 2019 Eddie Hung <eddie@fpgeh.com>
- *
- * 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"
-
-USING_YOSYS_NAMESPACE
-PRIVATE_NAMESPACE_BEGIN
-
-struct MuxpackWorker
-{
- Module *module;
- SigMap sigmap;
-
- int mux_count, pmux_count;
-
- pool<Cell*> remove_cells;
-
- dict<SigSpec, Cell*> sig_chain_next;
- dict<SigSpec, Cell*> sig_chain_prev;
- pool<SigBit> sigbit_with_non_chain_users;
- pool<Cell*> chain_start_cells;
- pool<Cell*> candidate_cells;
-
- void make_sig_chain_next_prev()
- {
- for (auto wire : module->wires())
- {
- if (wire->port_output || wire->get_bool_attribute("\\keep")) {
- for (auto bit : sigmap(wire))
- sigbit_with_non_chain_users.insert(bit);
- }
- }
-
- for (auto cell : module->cells())
- {
- if (cell->type.in("$mux", "$pmux") && !cell->get_bool_attribute("\\keep"))
- {
- SigSpec a_sig = sigmap(cell->getPort("\\A"));
- SigSpec b_sig;
- if (cell->type == "$mux")
- b_sig = sigmap(cell->getPort("\\B"));
- SigSpec y_sig = sigmap(cell->getPort("\\Y"));
-
- if (sig_chain_next.count(a_sig))
- for (auto a_bit : a_sig.bits())
- sigbit_with_non_chain_users.insert(a_bit);
- else {
- sig_chain_next[a_sig] = cell;
- candidate_cells.insert(cell);
- }
-
- if (!b_sig.empty()) {
- if (sig_chain_next.count(b_sig))
- for (auto b_bit : b_sig.bits())
- sigbit_with_non_chain_users.insert(b_bit);
- else {
- sig_chain_next[b_sig] = cell;
- candidate_cells.insert(cell);
- }
- }
-
- sig_chain_prev[y_sig] = cell;
- continue;
- }
-
- for (auto conn : cell->connections())
- if (cell->input(conn.first))
- for (auto bit : sigmap(conn.second))
- sigbit_with_non_chain_users.insert(bit);
- }
- }
-
- void find_chain_start_cells()
- {
- for (auto cell : candidate_cells)
- {
- log_debug("Considering %s (%s)\n", log_id(cell), log_id(cell->type));
-
- SigSpec next_sig = cell->getPort("\\A");
- if (sig_chain_prev.count(next_sig) == 0) {
- if (cell->type == "$mux") {
- next_sig = cell->getPort("\\B");
- if (sig_chain_prev.count(next_sig) == 0)
- goto start_cell;
- }
- else
- goto start_cell;
- }
-
- {
- for (auto bit : next_sig.bits())
- if (sigbit_with_non_chain_users.count(bit))
- goto start_cell;
-
- Cell *c1 = sig_chain_prev.at(next_sig);
- Cell *c2 = cell;
-
- if (c1->getParam("\\WIDTH") != c2->getParam("\\WIDTH"))
- goto start_cell;
- }
-
- continue;
-
- start_cell:
- chain_start_cells.insert(cell);
- }
- }
-
- vector<Cell*> create_chain(Cell *start_cell)
- {
- vector<Cell*> chain;
-
- Cell *c = start_cell;
- while (c != nullptr)
- {
- chain.push_back(c);
-
- SigSpec y_sig = sigmap(c->getPort("\\Y"));
-
- if (sig_chain_next.count(y_sig) == 0)
- break;
-
- c = sig_chain_next.at(y_sig);
- if (chain_start_cells.count(c) != 0)
- break;
- }
-
- return chain;
- }
-
- void process_chain(vector<Cell*> &chain)
- {
- if (GetSize(chain) < 2)
- return;
-
- int cursor = 0;
- while (cursor < GetSize(chain))
- {
- int cases = GetSize(chain) - cursor;
-
- Cell *first_cell = chain[cursor];
- dict<int, SigBit> taps_dict;
-
- if (cases < 2) {
- cursor++;
- continue;
- }
-
- Cell *last_cell = chain[cursor+cases-1];
-
- log("Converting %s.%s ... %s.%s to a pmux with %d cases.\n",
- log_id(module), log_id(first_cell), log_id(module), log_id(last_cell), cases);
-
- mux_count += cases;
- pmux_count += 1;
-
- first_cell->type = "$pmux";
- SigSpec b_sig = first_cell->getPort("\\B");
- SigSpec s_sig = first_cell->getPort("\\S");
-
- for (int i = 1; i < cases; i++) {
- Cell* prev_cell = chain[cursor+i-1];
- Cell* cursor_cell = chain[cursor+i];
- if (sigmap(prev_cell->getPort("\\Y")) == sigmap(cursor_cell->getPort("\\A"))) {
- b_sig.append(cursor_cell->getPort("\\B"));
- s_sig.append(cursor_cell->getPort("\\S"));
- }
- else {
- b_sig.append(cursor_cell->getPort("\\A"));
- s_sig.append(module->LogicNot(NEW_ID, cursor_cell->getPort("\\S")));
- }
- remove_cells.insert(cursor_cell);
- }
-
- first_cell->setPort("\\B", b_sig);
- first_cell->setPort("\\S", s_sig);
- first_cell->setParam("\\S_WIDTH", GetSize(s_sig));
- first_cell->setPort("\\Y", last_cell->getPort("\\Y"));
-
- cursor += cases;
- }
- }
-
- void cleanup()
- {
- for (auto cell : remove_cells)
- module->remove(cell);
-
- remove_cells.clear();
- sig_chain_next.clear();
- sig_chain_prev.clear();
- chain_start_cells.clear();
- candidate_cells.clear();
- }
-
- MuxpackWorker(Module *module) :
- module(module), sigmap(module), mux_count(0), pmux_count(0)
- {
- make_sig_chain_next_prev();
- find_chain_start_cells();
-
- for (auto c : chain_start_cells) {
- vector<Cell*> chain = create_chain(c);
- process_chain(chain);
- }
-
- cleanup();
- }
-};
-
-struct MuxpackPass : public Pass {
- MuxpackPass() : Pass("muxpack", "$mux/$pmux cascades to $pmux") { }
- void help() YS_OVERRIDE
- {
- // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
- log("\n");
- log(" muxpack [selection]\n");
- log("\n");
- log("This pass converts cascaded chains of $pmux cells (e.g. those create from case\n");
- log("constructs) and $mux cells (e.g. those created by if-else constructs) into \n");
- log("into $pmux cells.\n");
- log("\n");
- }
- void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
- {
- log_header(design, "Executing MUXPACK pass ($mux cell cascades to $pmux).\n");
-
- size_t argidx;
- for (argidx = 1; argidx < args.size(); argidx++)
- {
- break;
- }
- extra_args(args, argidx, design);
-
- int mux_count = 0;
- int pmux_count = 0;
-
- for (auto module : design->selected_modules()) {
- MuxpackWorker worker(module);
- mux_count += worker.mux_count;
- pmux_count += worker.pmux_count;
- }
-
- log("Converted %d (p)mux cells into %d pmux cells.\n", mux_count, pmux_count);
- }
-} MuxpackPass;
-
-PRIVATE_NAMESPACE_END
projects / yosys.git / commitdiff