yosys/passes/techmap/zinit.cc

89 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/sigtools.h"
#include "kernel/ffinit.h"
#include "kernel/ff.h"
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
struct ZinitPass : public Pass {
ZinitPass() : Pass("zinit", "add inverters so all FF are zero-initialized") { }
void help() override
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" zinit [options] [selection]\n");
log("\n");
log("Add inverters as needed to make all FFs zero-initialized.\n");
log("\n");
log(" -all\n");
log(" also add zero initialization to uninitialized FFs\n");
log("\n");
}
void execute(std::vector<std::string> args, RTLIL::Design *design) override
{
bool all_mode = false;
log_header(design, "Executing ZINIT pass (make all FFs zero-initialized).\n");
size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++)
{
if (args[argidx] == "-all") {
all_mode = true;
continue;
}
break;
}
extra_args(args, argidx, design);
for (auto module : design->selected_modules())
{
SigMap sigmap(module);
FfInitVals initvals(&sigmap, module);
for (auto cell : module->selected_cells())
{
if (!RTLIL::builtin_ff_cell_types().count(cell->type))
continue;
FfData ff(&initvals, cell);
log("FF init value for cell %s (%s): %s = %s\n", log_id(cell), log_id(cell->type),
log_signal(ff.sig_q), log_signal(ff.val_init));
pool<int> bits;
for (int i = 0; i < ff.width; i++) {
if (ff.val_init.bits[i] == State::S1)
bits.insert(i);
else if (ff.val_init.bits[i] != State::S0 && all_mode)
ff.val_init.bits[i] = State::S0;
}
ff.flip_bits(bits);
ff.emit();
}
}
}
} ZinitPass;
PRIVATE_NAMESPACE_END