yosys/passes/proc/proc_init.cc

115 lines
3.5 KiB
C++

/*
* 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/register.h"
#include "kernel/sigtools.h"
#include "kernel/log.h"
#include <stdlib.h>
#include <stdio.h>
static void proc_get_const(RTLIL::SigSpec &sig, RTLIL::CaseRule &rule)
{
assert(rule.compare.size() == 0);
while (1) {
sig.optimize();
RTLIL::SigSpec tmp = sig;
for (auto &it : rule.actions)
tmp.replace(it.first, it.second);
if (tmp == sig)
break;
sig = tmp;
}
}
static void proc_init(RTLIL::Module *mod, RTLIL::Process *proc)
{
bool found_init = false;
for (auto &sync : proc->syncs)
if (sync->type == RTLIL::SyncType::STi)
{
found_init = true;
log("Found init rule in `%s.%s'.\n", mod->name.c_str(), proc->name.c_str());
for (auto &action : sync->actions)
{
RTLIL::SigSpec lhs = action.first;
RTLIL::SigSpec rhs = action.second;
lhs.optimize();
proc_get_const(rhs, proc->root_case);
if (!rhs.is_fully_const())
log_cmd_error("Failed to get a constant init value for %s: %s\n", log_signal(lhs), log_signal(rhs));
int offset = 0;
for (size_t i = 0; i < lhs.chunks.size(); i++) {
if (lhs.chunks[i].wire == NULL)
continue;
RTLIL::Wire *wire = lhs.chunks[i].wire;
RTLIL::SigSpec value = rhs.extract(offset, lhs.chunks[i].width);
if (value.width != wire->width)
log_cmd_error("Init value is not for the entire wire: %s = %s\n", log_signal(lhs.chunks[i]), log_signal(value));
log(" Setting init value: %s = %s\n", log_signal(wire), log_signal(value));
wire->attributes["\\init"] = value.as_const();
offset += wire->width;
}
}
}
if (found_init) {
std::vector<RTLIL::SyncRule*> new_syncs;
for (auto &sync : proc->syncs)
if (sync->type == RTLIL::SyncType::STi)
delete sync;
else
new_syncs.push_back(sync);
proc->syncs.swap(new_syncs);
}
}
struct ProcInitPass : public Pass {
ProcInitPass() : Pass("proc_init", "convert initial block to init attributes") { }
virtual void help()
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" proc_init [selection]\n");
log("\n");
log("This pass extracts the 'init' actions from processes (generated from verilog\n");
log("'initial' blocks) and sets the initial value to the 'init' attribute on the\n");
log("respective wire.\n");
log("\n");
}
virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
{
log_header("Executing PROC_INIT pass (extract init attributes).\n");
extra_args(args, 1, design);
for (auto &mod_it : design->modules)
if (design->selected(mod_it.second))
for (auto &proc_it : mod_it.second->processes)
if (design->selected(mod_it.second, proc_it.second))
proc_init(mod_it.second, proc_it.second);
}
} ProcInitPass;