mirror of
https://github.com/YosysHQ/yosys
synced 2025-04-28 03:15:50 +00:00
85 lines
2.6 KiB
C++
85 lines
2.6 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/celltypes.h"
|
|
#include "kernel/sigtools.h"
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
|
|
USING_YOSYS_NAMESPACE
|
|
PRIVATE_NAMESPACE_BEGIN
|
|
|
|
struct SelectConstPass : public Pass {
|
|
SelectConstPass() : Pass("selectconst", "select objects with (mostly) constant input bits") { }
|
|
void help() override
|
|
{
|
|
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
|
|
log("\n");
|
|
log(" selectconst [ -frac <frac> ] {<selection>}\n");
|
|
log("\n");
|
|
log("Select cells with (mostly) constant input bits.\n");
|
|
log("\n");
|
|
log(" -frac\n");
|
|
log(" the fraction of constant input bits (default: 1.0).\n");
|
|
log("\n");
|
|
}
|
|
void execute(std::vector<std::string> args, RTLIL::Design *design) override
|
|
{
|
|
float frac = 1;
|
|
|
|
size_t argidx;
|
|
for (argidx = 1; argidx < args.size(); argidx++)
|
|
{
|
|
std::string arg = args[argidx];
|
|
if (arg == "-frac") {
|
|
frac = std::stof(args[++argidx]);
|
|
continue;
|
|
}
|
|
break;
|
|
}
|
|
extra_args(args, argidx, design);
|
|
|
|
for (auto module : design->selected_modules())
|
|
{
|
|
SigMap sigmap(module);
|
|
|
|
for (auto cell : module->selected_cells())
|
|
{
|
|
for (auto conn : cell->connections()) {
|
|
if (!cell->input(conn.first) || GetSize(conn.second) == 0)
|
|
continue;
|
|
|
|
SigPool sigpool;
|
|
for (int i = 0; i < GetSize(conn.second); i++) {
|
|
if (conn.second[i].wire == nullptr)
|
|
continue;
|
|
sigpool.add(sigmap(conn.second[i]));
|
|
}
|
|
if ((float) GetSize(sigpool) / GetSize(conn.second) >= frac) {
|
|
cell->set_bool_attribute("\\mostlyconst");
|
|
log("Marking %s as mostly constant (%d/%d bits constant).\n", log_id(cell), GetSize(sigpool), GetSize(conn.second));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
} SelectConstPass;
|
|
|
|
PRIVATE_NAMESPACE_END
|