yosys/passes/techmap/deminout.cc

141 lines
3.9 KiB
C++

/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Claire Xenia Wolf <claire@yosyshq.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 DeminoutPass : public Pass {
DeminoutPass() : Pass("deminout", "demote inout ports to input or output") { }
void help() override
{
log("\n");
log(" deminout [options] [selection]\n");
log("\n");
log("\"Demote\" inout ports to input or output ports, if possible.\n");
log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
log_header(design, "Executing DEMINOUT pass (demote inout ports to input or output).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
// if (args[argidx] == "-bits") {
// flag_bits = true;
// continue;
// }
break;
}
extra_args(args, argidx, design);
bool keep_running = true;
while (keep_running)
{
keep_running = false;
for (auto module : design->selected_modules())
{
SigMap sigmap(module);
pool<SigBit> bits_written, bits_used, bits_inout, bits_tribuf;
dict<SigBit, int> bits_numports;
for (auto wire : module->wires())
if (wire->port_id)
for (auto bit : sigmap(wire))
bits_numports[bit]++;
for (auto cell : module->cells())
for (auto &conn : cell->connections())
{
bool cellport_out = cell->output(conn.first) || !cell->known();
bool cellport_in = cell->input(conn.first) || !cell->known();
if (cellport_out && cellport_in)
for (auto bit : sigmap(conn.second))
bits_inout.insert(bit);
if (cellport_out)
for (auto bit : sigmap(conn.second))
bits_written.insert(bit);
if (cellport_in)
for (auto bit : sigmap(conn.second))
bits_used.insert(bit);
if (conn.first == ID::Y && cell->type.in(ID($mux), ID($pmux), ID($_MUX_), ID($_TBUF_), ID($tribuf)))
{
bool tribuf = cell->type.in(ID($_TBUF_), ID($tribuf));
if (!tribuf) {
for (auto &c : cell->connections()) {
if (!c.first.in(ID::A, ID::B))
continue;
for (auto b : sigmap(c.second))
if (b == State::Sz)
tribuf = true;
}
}
if (tribuf)
for (auto bit : sigmap(conn.second))
bits_tribuf.insert(bit);
}
}
for (auto wire : module->selected_wires())
if (wire->port_input && wire->port_output)
{
bool new_input = false;
bool new_output = false;
for (auto bit : sigmap(wire))
{
if (bits_numports[bit] > 1 || bits_inout.count(bit))
new_input = true, new_output = true;
if (!bit.wire)
new_output = true;
if (bits_written.count(bit)) {
new_output = true;
if (bits_tribuf.count(bit))
goto tribuf_bit;
} else {
tribuf_bit:
new_input = true;
}
}
if (new_input != new_output) {
log("Demoting inout port %s.%s to %s.\n", log_id(module), log_id(wire), new_input ? "input" : "output");
wire->port_input = new_input;
wire->port_output = new_output;
keep_running = true;
}
}
}
}
}
} DeminoutPass;
PRIVATE_NAMESPACE_END