yosys/frontends/blif/blifparse.cc

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/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2012 Claire Xenia Wolf <claire@yosyshq.com>
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*
* 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.
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*
* 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 "blifparse.h"
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YOSYS_NAMESPACE_BEGIN
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static bool read_next_line(char *&buffer, size_t &buffer_size, int &line_count, std::istream &f)
{
string strbuf;
int buffer_len = 0;
buffer[0] = 0;
while (1)
{
buffer_len += strlen(buffer + buffer_len);
while (buffer_len > 0 && (buffer[buffer_len-1] == ' ' || buffer[buffer_len-1] == '\t' ||
buffer[buffer_len-1] == '\r' || buffer[buffer_len-1] == '\n'))
buffer[--buffer_len] = 0;
if (buffer_size-buffer_len < 4096) {
buffer_size *= 2;
buffer = (char*)realloc(buffer, buffer_size);
}
if (buffer_len == 0 || buffer[buffer_len-1] == '\\') {
if (buffer_len > 0 && buffer[buffer_len-1] == '\\')
buffer[--buffer_len] = 0;
line_count++;
if (!std::getline(f, strbuf))
return false;
while (buffer_size-buffer_len < strbuf.size()+1) {
buffer_size *= 2;
buffer = (char*)realloc(buffer, buffer_size);
}
strcpy(buffer+buffer_len, strbuf.c_str());
} else
return true;
}
}
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static std::pair<RTLIL::IdString, int> wideports_split(std::string name)
{
int pos = -1;
if (name.empty() || name.back() != ']')
goto failed;
for (int i = 0; i+1 < GetSize(name); i++) {
if (name[i] == '[')
pos = i;
else if (name[i] != '-' && (name[i] < '0' || name[i] > '9'))
pos = -1;
else if (name[i] == '-' && ((i != pos+1) || name[i+1] == ']'))
pos = -1;
else if (i == pos+2 && name[i] == '0' && name[i-1] == '-')
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pos = -1;
else if (i == pos+1 && name[i] == '0' && name[i+1] != ']')
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pos = -1;
}
if (pos >= 0)
return std::pair<RTLIL::IdString, int>("\\" + name.substr(0, pos), atoi(name.c_str() + pos+1));
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failed:
return std::pair<RTLIL::IdString, int>(RTLIL::IdString(), 0);
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}
void parse_blif(RTLIL::Design *design, std::istream &f, IdString dff_name, bool run_clean, bool sop_mode, bool wideports)
{
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RTLIL::Module *module = nullptr;
RTLIL::Const *lutptr = NULL;
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RTLIL::Cell *sopcell = NULL;
RTLIL::Cell *lastcell = nullptr;
RTLIL::State lut_default_state = RTLIL::State::Sx;
std::string err_reason;
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int blif_maxnum = 0, sopmode = -1;
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auto blif_wire = [&](const std::string &wire_name) -> Wire*
{
if (wire_name[0] == '$')
{
for (int i = 0; i+1 < GetSize(wire_name); i++)
{
if (wire_name[i] != '$')
continue;
int len = 0;
while (i+len+1 < GetSize(wire_name) && '0' <= wire_name[i+len+1] && wire_name[i+len+1] <= '9')
len++;
if (len > 0) {
string num_str = wire_name.substr(i+1, len);
int num = atoi(num_str.c_str()) & 0x0fffffff;
blif_maxnum = std::max(blif_maxnum, num);
}
}
}
IdString wire_id = RTLIL::escape_id(wire_name);
Wire *wire = module->wire(wire_id);
if (wire == nullptr)
wire = module->addWire(wire_id);
return wire;
};
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dict<RTLIL::IdString, RTLIL::Const> *obj_attributes = nullptr;
dict<RTLIL::IdString, RTLIL::Const> *obj_parameters = nullptr;
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dict<RTLIL::IdString, std::pair<int, bool>> wideports_cache;
size_t buffer_size = 4096;
char *buffer = (char*)malloc(buffer_size);
int line_count = 0;
while (1)
{
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if (!read_next_line(buffer, buffer_size, line_count, f)) {
if (module != nullptr)
goto error;
free(buffer);
return;
}
continue_without_read:
if (buffer[0] == '#')
continue;
if (buffer[0] == '.')
{
if (lutptr) {
for (auto &bit : lutptr->bits)
if (bit == RTLIL::State::Sx)
bit = lut_default_state;
lutptr = NULL;
lut_default_state = RTLIL::State::Sx;
}
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if (sopcell) {
sopcell = NULL;
sopmode = -1;
}
char *cmd = strtok(buffer, " \t\r\n");
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if (!strcmp(cmd, ".model")) {
if (module != nullptr)
goto error;
module = new RTLIL::Module;
lastcell = nullptr;
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char *name = strtok(NULL, " \t\r\n");
if (name == nullptr)
goto error;
module->name = RTLIL::escape_id(name);
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obj_attributes = &module->attributes;
obj_parameters = nullptr;
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if (design->module(module->name))
log_error("Duplicate definition of module %s in line %d!\n", log_id(module->name), line_count);
design->add(module);
continue;
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}
if (module == nullptr)
goto error;
if (!strcmp(cmd, ".blackbox"))
{
module->attributes[ID::blackbox] = RTLIL::Const(1);
continue;
}
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if (!strcmp(cmd, ".end"))
{
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for (auto &wp : wideports_cache)
{
auto name = wp.first;
int width = wp.second.first;
bool isinput = wp.second.second;
RTLIL::Wire *wire = module->addWire(name, width);
wire->port_input = isinput;
wire->port_output = !isinput;
for (int i = 0; i < width; i++) {
RTLIL::IdString other_name = name.str() + stringf("[%d]", i);
RTLIL::Wire *other_wire = module->wire(other_name);
if (other_wire) {
other_wire->port_input = false;
other_wire->port_output = false;
if (isinput)
module->connect(other_wire, SigSpec(wire, i));
else
module->connect(SigSpec(wire, i), other_wire);
}
}
}
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module->fixup_ports();
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wideports_cache.clear();
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if (run_clean)
{
Const buffer_lut(vector<RTLIL::State>({State::S0, State::S1}));
vector<Cell*> remove_cells;
for (auto cell : module->cells())
if (cell->type == ID($lut) && cell->getParam(ID::LUT) == buffer_lut) {
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module->connect(cell->getPort(ID::Y), cell->getPort(ID::A));
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remove_cells.push_back(cell);
}
for (auto cell : remove_cells)
module->remove(cell);
Wire *true_wire = module->wire(ID($true));
Wire *false_wire = module->wire(ID($false));
Wire *undef_wire = module->wire(ID($undef));
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if (true_wire != nullptr)
module->rename(true_wire, stringf("$true$%d", ++blif_maxnum));
if (false_wire != nullptr)
module->rename(false_wire, stringf("$false$%d", ++blif_maxnum));
if (undef_wire != nullptr)
module->rename(undef_wire, stringf("$undef$%d", ++blif_maxnum));
autoidx = std::max(autoidx, blif_maxnum+1);
blif_maxnum = 0;
}
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module = nullptr;
lastcell = nullptr;
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obj_attributes = nullptr;
obj_parameters = nullptr;
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continue;
}
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if (!strcmp(cmd, ".inputs") || !strcmp(cmd, ".outputs"))
{
char *p;
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while ((p = strtok(NULL, " \t\r\n")) != NULL)
{
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RTLIL::IdString wire_name(stringf("\\%s", p));
RTLIL::Wire *wire = module->wire(wire_name);
if (wire == nullptr)
wire = module->addWire(wire_name);
if (!strcmp(cmd, ".inputs"))
wire->port_input = true;
else
wire->port_output = true;
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if (wideports) {
std::pair<RTLIL::IdString, int> wp = wideports_split(p);
if (!wp.first.empty() && wp.second >= 0) {
wideports_cache[wp.first].first = std::max(wideports_cache[wp.first].first, wp.second + 1);
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wideports_cache[wp.first].second = !strcmp(cmd, ".inputs");
}
}
}
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obj_attributes = nullptr;
obj_parameters = nullptr;
continue;
}
if (!strcmp(cmd, ".cname"))
{
char *p = strtok(NULL, " \t\r\n");
if (p == NULL)
goto error;
if(lastcell == nullptr || module == nullptr)
{
err_reason = stringf("No primitive object to attach .cname %s.", p);
goto error_with_reason;
}
module->rename(lastcell, RTLIL::escape_id(p));
continue;
}
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if (!strcmp(cmd, ".attr") || !strcmp(cmd, ".param")) {
char *n = strtok(NULL, " \t\r\n");
char *v = strtok(NULL, "\r\n");
IdString id_n = RTLIL::escape_id(n);
Const const_v;
if (v[0] == '"') {
std::string str(v+1);
if (str.back() == '"')
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str.resize(str.size()-1);
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const_v = Const(str);
} else {
int n = strlen(v);
const_v.bits.resize(n);
for (int i = 0; i < n; i++)
const_v.bits[i] = v[n-i-1] != '0' ? State::S1 : State::S0;
}
if (!strcmp(cmd, ".attr")) {
if (obj_attributes == nullptr) {
err_reason = stringf("No object to attach .attr too.");
goto error_with_reason;
}
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(*obj_attributes)[id_n] = const_v;
} else {
if (obj_parameters == nullptr) {
err_reason = stringf("No object to attach .param too.");
goto error_with_reason;
}
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(*obj_parameters)[id_n] = const_v;
}
continue;
}
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if (!strcmp(cmd, ".latch"))
{
char *d = strtok(NULL, " \t\r\n");
char *q = strtok(NULL, " \t\r\n");
char *edge = strtok(NULL, " \t\r\n");
char *clock = strtok(NULL, " \t\r\n");
char *init = strtok(NULL, " \t\r\n");
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RTLIL::Cell *cell = nullptr;
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if (clock == nullptr && edge != nullptr) {
init = edge;
edge = nullptr;
}
if (init != nullptr && (init[0] == '0' || init[0] == '1'))
blif_wire(q)->attributes[ID::init] = Const(init[0] == '1' ? 1 : 0, 1);
if (clock == nullptr)
goto no_latch_clock;
if (!strcmp(edge, "re"))
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cell = module->addDff(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q));
else if (!strcmp(edge, "fe"))
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cell = module->addDff(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q), false);
else if (!strcmp(edge, "ah"))
cell = module->addDlatch(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q));
else if (!strcmp(edge, "al"))
cell = module->addDlatch(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q), false);
else {
no_latch_clock:
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if (dff_name.empty()) {
cell = module->addFf(NEW_ID, blif_wire(d), blif_wire(q));
} else {
cell = module->addCell(NEW_ID, dff_name);
cell->setPort(ID::D, blif_wire(d));
cell->setPort(ID::Q, blif_wire(q));
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}
}
lastcell = cell;
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obj_attributes = &cell->attributes;
obj_parameters = &cell->parameters;
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continue;
}
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if (!strcmp(cmd, ".gate") || !strcmp(cmd, ".subckt"))
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{
char *p = strtok(NULL, " \t\r\n");
if (p == NULL)
goto error;
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IdString celltype = RTLIL::escape_id(p);
RTLIL::Cell *cell = module->addCell(NEW_ID, celltype);
RTLIL::Module *cell_mod = design->module(celltype);
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dict<RTLIL::IdString, dict<int, SigBit>> cell_wideports_cache;
while ((p = strtok(NULL, " \t\r\n")) != NULL)
{
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char *q = strchr(p, '=');
if (q == NULL || !q[0])
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goto error;
*(q++) = 0;
if (wideports) {
std::pair<RTLIL::IdString, int> wp = wideports_split(p);
if (wp.first.empty())
cell->setPort(RTLIL::escape_id(p), *q ? blif_wire(q) : SigSpec());
else
cell_wideports_cache[wp.first][wp.second] = blif_wire(q);
} else {
cell->setPort(RTLIL::escape_id(p), *q ? blif_wire(q) : SigSpec());
}
}
for (auto &it : cell_wideports_cache)
{
int width = 0;
int offset = 0;
bool upto = false;
for (auto &b : it.second)
width = std::max(width, b.first + 1);
if (cell_mod) {
Wire *cell_port = cell_mod->wire(it.first);
if (cell_port && (cell_port->port_input || cell_port->port_output)) {
offset = cell_port->start_offset;
upto = cell_port->upto;
width = cell_port->width;
}
}
SigSpec sig;
for (int i = 0; i < width; i++) {
int idx = offset + (upto ? width - 1 - i: i);
if (it.second.count(idx))
sig.append(it.second.at(idx));
else
sig.append(module->addWire(NEW_ID));
}
cell->setPort(it.first, sig);
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}
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lastcell = cell;
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obj_attributes = &cell->attributes;
obj_parameters = &cell->parameters;
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continue;
}
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obj_attributes = nullptr;
obj_parameters = nullptr;
if (!strcmp(cmd, ".barbuf") || !strcmp(cmd, ".conn"))
{
char *p = strtok(NULL, " \t\r\n");
if (p == NULL)
goto error;
char *q = strtok(NULL, " \t\r\n");
if (q == NULL)
goto error;
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module->connect(blif_wire(q), blif_wire(p));
continue;
}
if (!strcmp(cmd, ".names"))
{
char *p;
RTLIL::SigSpec input_sig, output_sig;
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while ((p = strtok(NULL, " \t\r\n")) != NULL)
input_sig.append(blif_wire(p));
output_sig = input_sig.extract(input_sig.size()-1, 1);
input_sig = input_sig.extract(0, input_sig.size()-1);
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if (input_sig.size() == 0)
{
RTLIL::State state = RTLIL::State::Sa;
while (1) {
if (!read_next_line(buffer, buffer_size, line_count, f))
goto error;
for (int i = 0; buffer[i]; i++) {
if (buffer[i] == ' ' || buffer[i] == '\t')
continue;
if (i == 0 && buffer[i] == '.')
goto finished_parsing_constval;
if (buffer[i] == '0') {
if (state == RTLIL::State::S1)
goto error;
state = RTLIL::State::S0;
continue;
}
if (buffer[i] == '1') {
if (state == RTLIL::State::S0)
goto error;
state = RTLIL::State::S1;
continue;
}
goto error;
}
}
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finished_parsing_constval:
if (state == RTLIL::State::Sa)
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state = RTLIL::State::S0;
if (output_sig.as_wire()->name == ID($undef))
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state = RTLIL::State::Sx;
module->connect(RTLIL::SigSig(output_sig, state));
goto continue_without_read;
}
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if (sop_mode)
{
sopcell = module->addCell(NEW_ID, ID($sop));
sopcell->parameters[ID::WIDTH] = RTLIL::Const(input_sig.size());
sopcell->parameters[ID::DEPTH] = 0;
sopcell->parameters[ID::TABLE] = RTLIL::Const();
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sopcell->setPort(ID::A, input_sig);
sopcell->setPort(ID::Y, output_sig);
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sopmode = -1;
lastcell = sopcell;
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}
else
{
RTLIL::Cell *cell = module->addCell(NEW_ID, ID($lut));
cell->parameters[ID::WIDTH] = RTLIL::Const(input_sig.size());
cell->parameters[ID::LUT] = RTLIL::Const(RTLIL::State::Sx, 1 << input_sig.size());
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cell->setPort(ID::A, input_sig);
cell->setPort(ID::Y, output_sig);
lutptr = &cell->parameters.at(ID::LUT);
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lut_default_state = RTLIL::State::Sx;
lastcell = cell;
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}
continue;
}
goto error;
}
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if (lutptr == NULL && sopcell == NULL)
goto error;
char *input = strtok(buffer, " \t\r\n");
char *output = strtok(NULL, " \t\r\n");
if (input == NULL || output == NULL || (strcmp(output, "0") && strcmp(output, "1")))
goto error;
int input_len = strlen(input);
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if (sopcell)
{
log_assert(sopcell->parameters[ID::WIDTH].as_int() == input_len);
sopcell->parameters[ID::DEPTH] = sopcell->parameters[ID::DEPTH].as_int() + 1;
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for (int i = 0; i < input_len; i++)
switch (input[i]) {
case '0':
sopcell->parameters[ID::TABLE].bits.push_back(State::S1);
sopcell->parameters[ID::TABLE].bits.push_back(State::S0);
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break;
case '1':
sopcell->parameters[ID::TABLE].bits.push_back(State::S0);
sopcell->parameters[ID::TABLE].bits.push_back(State::S1);
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break;
default:
sopcell->parameters[ID::TABLE].bits.push_back(State::S0);
sopcell->parameters[ID::TABLE].bits.push_back(State::S0);
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break;
}
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if (sopmode == -1) {
sopmode = (*output == '1');
if (!sopmode) {
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SigSpec outnet = sopcell->getPort(ID::Y);
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SigSpec tempnet = module->addWire(NEW_ID);
module->addNotGate(NEW_ID, tempnet, outnet);
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sopcell->setPort(ID::Y, tempnet);
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}
} else
log_assert(sopmode == (*output == '1'));
}
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if (lutptr)
{
if (input_len > 12)
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goto error;
for (int i = 0; i < (1 << input_len); i++) {
for (int j = 0; j < input_len; j++) {
char c1 = input[j];
if (c1 != '-') {
char c2 = (i & (1 << j)) != 0 ? '1' : '0';
if (c1 != c2)
goto try_next_value;
}
}
lutptr->bits.at(i) = !strcmp(output, "0") ? RTLIL::State::S0 : RTLIL::State::S1;
try_next_value:;
}
lut_default_state = !strcmp(output, "0") ? RTLIL::State::S1 : RTLIL::State::S0;
}
}
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return;
error:
log_error("Syntax error in line %d!\n", line_count);
error_with_reason:
log_error("Syntax error in line %d: %s\n", line_count, err_reason.c_str());
}
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struct BlifFrontend : public Frontend {
BlifFrontend() : Frontend("blif", "read BLIF file") { }
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void help() override
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{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
log(" read_blif [options] [filename]\n");
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log("\n");
log("Load modules from a BLIF file into the current design.\n");
log("\n");
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log(" -sop\n");
log(" Create $sop cells instead of $lut cells\n");
log("\n");
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log(" -wideports\n");
log(" Merge ports that match the pattern 'name[int]' into a single\n");
log(" multi-bit port 'name'.\n");
log("\n");
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}
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void execute(std::istream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design) override
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{
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bool sop_mode = false;
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bool wideports = false;
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log_header(design, "Executing BLIF frontend.\n");
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size_t argidx;
for (argidx = 1; argidx < args.size(); argidx++) {
std::string arg = args[argidx];
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if (arg == "-sop") {
sop_mode = true;
continue;
}
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if (arg == "-wideports") {
wideports = true;
continue;
}
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break;
}
extra_args(f, filename, args, argidx);
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parse_blif(design, *f, "", true, sop_mode, wideports);
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}
} BlifFrontend;
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YOSYS_NAMESPACE_END