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+/*
+ * 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"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct AssertpmuxWorker
+{
+ Module *module;
+ SigMap sigmap;
+
+ bool flag_noinit;
+ bool flag_always;
+
+ // get<0> ... mux cell
+ // get<1> ... mux port index
+ // get<2> ... mux bit index
+ dict<SigBit, pool<tuple<Cell*, int, int>>> sigbit_muxusers;
+
+ dict<SigBit, SigBit> sigbit_actsignals;
+ dict<SigSpec, SigBit> sigspec_actsignals;
+ dict<tuple<Cell*, int>, SigBit> muxport_actsignal;
+
+ AssertpmuxWorker(Module *module, bool flag_noinit, bool flag_always) :
+ module(module), sigmap(module), flag_noinit(flag_noinit), flag_always(flag_always)
+ {
+ for (auto wire : module->wires())
+ {
+ if (wire->port_output)
+ for (auto bit : sigmap(wire))
+ sigbit_actsignals[bit] = State::S1;
+ }
+
+ for (auto cell : module->cells())
+ {
+ if (cell->type.in("$mux", "$pmux"))
+ {
+ int width = cell->getParam("\\WIDTH").as_int();
+ int numports = cell->type == "$mux" ? 2 : cell->getParam("\\S_WIDTH").as_int() + 1;
+
+ SigSpec sig_a = sigmap(cell->getPort("\\A"));
+ SigSpec sig_b = sigmap(cell->getPort("\\B"));
+ SigSpec sig_s = sigmap(cell->getPort("\\S"));
+
+ for (int i = 0; i < numports; i++) {
+ SigSpec bits = i == 0 ? sig_a : sig_b.extract(width*(i-1), width);
+ for (int k = 0; k < width; k++) {
+ tuple<Cell*, int, int> muxuser(cell, i, k);
+ sigbit_muxusers[bits[k]].insert(muxuser);
+ }
+ }
+ }
+ else
+ {
+ for (auto &conn : cell->connections()) {
+ if (!cell->known() || cell->input(conn.first))
+ for (auto bit : sigmap(conn.second))
+ sigbit_actsignals[bit] = State::S1;
+ }
+ }
+ }
+ }
+
+ SigBit get_bit_activation(SigBit bit)
+ {
+ sigmap.apply(bit);
+
+ if (sigbit_actsignals.count(bit) == 0)
+ {
+ SigSpec output;
+
+ for (auto muxuser : sigbit_muxusers.at(bit))
+ {
+ Cell *cell = std::get<0>(muxuser);
+ int portidx = std::get<1>(muxuser);
+ int bitidx = std::get<2>(muxuser);
+
+ tuple<Cell*, int> muxport(cell, portidx);
+
+ if (muxport_actsignal.count(muxport) == 0) {
+ if (portidx == 0)
+ muxport_actsignal[muxport] = module->LogicNot(NEW_ID, cell->getPort("\\S"));
+ else
+ muxport_actsignal[muxport] = cell->getPort("\\S")[portidx-1];
+ }
+
+ output.append(module->LogicAnd(NEW_ID, muxport_actsignal.at(muxport), get_bit_activation(cell->getPort("\\Y")[bitidx])));
+ }
+
+ output.sort_and_unify();
+
+ if (GetSize(output) == 0)
+ output = State::S0;
+ else if (GetSize(output) > 1)
+ output = module->ReduceOr(NEW_ID, output);
+
+ sigbit_actsignals[bit] = output.as_bit();
+ }
+
+ return sigbit_actsignals.at(bit);
+ }
+
+ SigBit get_activation(SigSpec sig)
+ {
+ sigmap.apply(sig);
+ sig.sort_and_unify();
+
+ if (sigspec_actsignals.count(sig) == 0)
+ {
+ SigSpec output;
+
+ for (auto bit : sig)
+ output.append(get_bit_activation(bit));
+
+ output.sort_and_unify();
+
+ if (GetSize(output) == 0)
+ output = State::S0;
+ else if (GetSize(output) > 1)
+ output = module->ReduceOr(NEW_ID, output);
+
+ sigspec_actsignals[sig] = output.as_bit();
+ }
+
+ return sigspec_actsignals.at(sig);
+ }
+
+ void run(Cell *pmux)
+ {
+ log("Adding assert for $pmux cell %s.%s.\n", log_id(module), log_id(pmux));
+
+ int swidth = pmux->getParam("\\S_WIDTH").as_int();
+ int cntbits = ceil_log2(swidth+1);
+
+ SigSpec sel = pmux->getPort("\\S");
+ SigSpec cnt(State::S0, cntbits);
+
+ for (int i = 0; i < swidth; i++)
+ cnt = module->Add(NEW_ID, cnt, sel[i]);
+
+ SigSpec assert_a = module->Le(NEW_ID, cnt, SigSpec(1, cntbits));
+ SigSpec assert_en;
+
+ if (flag_noinit)
+ assert_en.append(module->LogicNot(NEW_ID, module->Initstate(NEW_ID)));
+
+ if (!flag_always)
+ assert_en.append(get_activation(pmux->getPort("\\Y")));
+
+ if (GetSize(assert_en) == 0)
+ assert_en = State::S1;
+
+ if (GetSize(assert_en) == 2)
+ assert_en = module->LogicAnd(NEW_ID, assert_en[0], assert_en[1]);
+
+ Cell *assert_cell = module->addAssert(NEW_ID, assert_a, assert_en);
+
+ if (pmux->attributes.count("\\src") != 0)
+ assert_cell->attributes["\\src"] = pmux->attributes.at("\\src");
+ }
+};
+
+struct AssertpmuxPass : public Pass {
+ AssertpmuxPass() : Pass("assertpmux", "convert internal signals to module ports") { }
+ virtual void help()
+ {
+ // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+ log("\n");
+ log(" assertpmux [options] [selection]\n");
+ log("\n");
+ log("This command adds asserts to the design that assert that all parallel muxes\n");
+ log("($pmux cells) have a maximum of one of their inputs enable at any time.\n");
+ log("\n");
+ log(" -noinit\n");
+ log(" do not enforce the pmux condition during the init state\n");
+ log("\n");
+ log(" -always\n");
+ log(" usually the $pmux condition is only checked when the $pmux output\n");
+ log(" is used be the mux tree it drives. this option will deactivate this\n");
+ log(" additional constrained and check the $pmux condition always.\n");
+ log("\n");
+ }
+ virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+ {
+ bool flag_noinit = false;
+ bool flag_always = false;
+
+ log_header(design, "Executing ASSERTPMUX pass (add asserts for $pmux cells).\n");
+
+ size_t argidx;
+ for (argidx = 1; argidx < args.size(); argidx++)
+ {
+ if (args[argidx] == "-noinit") {
+ flag_noinit = true;
+ continue;
+ }
+ if (args[argidx] == "-always") {
+ flag_always = true;
+ continue;
+ }
+ break;
+ }
+ extra_args(args, argidx, design);
+
+ for (auto module : design->selected_modules())
+ {
+ AssertpmuxWorker worker(module, flag_noinit, flag_always);
+ vector<Cell*> pmux_cells;
+
+ for (auto cell : module->selected_cells())
+ if (cell->type == "$pmux")
+ pmux_cells.push_back(cell);
+
+ for (auto cell : pmux_cells)
+ worker.run(cell);
+ }
+
+ }
+} AssertpmuxPass;
+
+PRIVATE_NAMESPACE_END