yosys/passes/cmds/future.cc

141 lines
4.0 KiB
C++

/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2023 Jannis Harder <jix@yosyshq.com> <me@jix.one>
*
* 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/celltypes.h"
#include "kernel/ff.h"
#include "kernel/ffinit.h"
#include "kernel/modtools.h"
#include "kernel/sigtools.h"
#include "kernel/utils.h"
#include "kernel/yosys.h"
#include <deque>
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
struct FutureOptions {
};
struct FutureWorker {
Module *module;
FutureOptions options;
ModWalker modwalker;
SigMap &sigmap;
FfInitVals initvals;
dict<SigBit, SigBit> future_ff_signals;
FutureWorker(Module *module, FutureOptions options) :
module(module), options(options), modwalker(module->design), sigmap(modwalker.sigmap)
{
modwalker.setup(module);
initvals.set(&modwalker.sigmap, module);
std::vector<Cell *> replaced_cells;
for (auto cell : module->selected_cells()) {
if (cell->type != ID($future_ff))
continue;
module->connect(cell->getPort(ID::Y), future_ff(cell->getPort(ID::A)));
replaced_cells.push_back(cell);
}
for (auto cell : replaced_cells) {
module->remove(cell);
}
}
SigSpec future_ff(SigSpec sig)
{
for (auto &bit : sig) {
bit = future_ff(bit);
}
return sig;
}
SigBit future_ff(SigBit bit)
{
if (!bit.is_wire())
return bit;
auto found = future_ff_signals.find(bit);
if (found != future_ff_signals.end())
return found->second;
auto found_driver = modwalker.signal_drivers.find(bit);
if (found_driver == modwalker.signal_drivers.end() || found_driver->second.size() < 1)
log_error("No driver for future_ff target signal %s found\n", log_signal(bit));
if (found_driver->second.size() > 1)
log_error("Found multiple drivers for future_ff target signal %s\n", log_signal(bit));
auto driver = *found_driver->second.begin();
if (!RTLIL::builtin_ff_cell_types().count(driver.cell->type) && driver.cell->type != ID($anyinit))
log_error("Driver for future_ff target signal %s has non-FF cell type %s\n", log_signal(bit), log_id(driver.cell->type));
FfData ff(&initvals, driver.cell);
if (!ff.has_clk && !ff.has_gclk)
log_error("Driver for future_ff target signal %s has cell type %s, which is not clocked\n", log_signal(bit),
log_id(driver.cell->type));
ff.unmap_ce_srst();
// We insert all bits into the mapping, because unmap_ce_srst might
// have removed the cell which is still present in the modwalker data.
// By inserting all bits driven by th FF we ensure that we'll never use
// that stale modwalker data again.
for (int i = 0; i < ff.width; ++i) {
future_ff_signals.emplace(ff.sig_q[i], ff.sig_d[i]);
}
return future_ff_signals.at(bit);
}
};
struct FuturePass : public Pass {
FuturePass() : Pass("future", "resolve future sampled value functions") {}
void help() override
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" future [options] [selection]\n");
log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
FutureOptions options;
log_header(design, "Executing FUTURE pass.\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) {
break;
}
extra_args(args, argidx, design);
for (auto module : design->selected_modules()) {
FutureWorker worker(module, options);
}
}
} FuturePass;
PRIVATE_NAMESPACE_END