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Merge pull request Silimate#12 from alaindargelas/splitnetlist
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Split netlist pass
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akashlevy authored Oct 22, 2024
2 parents 9ba609a + 6d39513 commit 85beec7
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1 change: 1 addition & 0 deletions Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -744,6 +744,7 @@ OBJS += passes/cmds/splitfanout.o
OBJS += passes/cmds/splitnets.o
OBJS += passes/cmds/tee.o
OBJS += passes/cmds/activity.o
OBJS += passes/cmds/splitnetlist.o
OBJS += passes/sat/sim.o

include $(YOSYS_SRC)/passes/hierarchy/Makefile.inc
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243 changes: 243 additions & 0 deletions passes/cmds/splitnetlist.cc
Original file line number Diff line number Diff line change
@@ -0,0 +1,243 @@
#include "kernel/sigtools.h"
#include "kernel/yosys.h"
#include <set>

USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN

// Recursively traverses backward from a sig, record if a cell was traversed, and push onto the cell's inputs.
// Similarly with assign statements traverses lhs -> rhs
void recordTransFanin(RTLIL::SigSpec &sig, dict<RTLIL::SigSpec, std::set<Cell *> *> &sig2CellsInFanin,
dict<RTLIL::SigSpec, RTLIL::SigSpec> &lhsSig2RhsSig, std::set<Cell *> &visitedCells, std::set<RTLIL::SigSpec> &visitedSigSpec)
{
if (sig.is_fully_const()) {
return;
}
if (visitedSigSpec.count(sig)) {
return;
}
visitedSigSpec.insert(sig);
if (sig2CellsInFanin.count(sig)) {
std::set<Cell *> *sigFanin = sig2CellsInFanin[sig];
for (std::set<Cell *>::iterator it = sigFanin->begin(); it != sigFanin->end(); it++) {
Cell *cell = *it;
if (visitedCells.count(cell)) {
continue;
}
visitedCells.insert(cell);
for (auto &conn : cell->connections()) {
IdString portName = conn.first;
RTLIL::SigSpec actual = conn.second;

if (cell->input(portName)) {
if (!actual.is_chunk()) {
for (auto it = actual.chunks().rbegin(); it != actual.chunks().rend(); ++it) {
RTLIL::SigSpec sub_actual = *it;
recordTransFanin(sub_actual, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
}
} else {
recordTransFanin(actual, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
}
}
}
}
}
if (lhsSig2RhsSig.count(sig)) {
RTLIL::SigSpec rhs = lhsSig2RhsSig[sig];
recordTransFanin(rhs, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
}
}

// Signal cell driver(s), precompute a cell output signal to a cell map
void sigCellDrivers(RTLIL::Design *design, dict<RTLIL::SigSpec, std::set<Cell *> *> &sig2CellsInFanin)
{
for (auto cell : design->top_module()->cells()) {
for (auto &conn : cell->connections()) {
IdString portName = conn.first;
RTLIL::SigSpec actual = conn.second;
std::set<Cell *> *newSet;
if (cell->output(portName)) {
if (!actual.is_chunk()) {
for (auto it = actual.chunks().rbegin(); it != actual.chunks().rend(); ++it) {
RTLIL::SigSpec sub_actual = *it;
if (sig2CellsInFanin.count(sub_actual)) {
newSet = sig2CellsInFanin[sub_actual];
} else {
newSet = new std::set<Cell *>;
sig2CellsInFanin[sub_actual] = newSet;
}
newSet->insert(cell);
}
} else {
if (sig2CellsInFanin.count(actual)) {
newSet = sig2CellsInFanin[actual];
} else {
newSet = new std::set<Cell *>;
sig2CellsInFanin[actual] = newSet;
}
newSet->insert(cell);
}
}
}
}
}

// Assign statements fanin, traces the lhs to rhs sigspecs and precompute a map
void lhs2rhs(RTLIL::Design *design, dict<RTLIL::SigSpec, RTLIL::SigSpec> &lhsSig2rhsSig)
{
for (auto it = design->top_module()->connections().begin(); it != design->top_module()->connections().end(); ++it) {
RTLIL::SigSpec lhs = it->first;
RTLIL::SigSpec rhs = it->second;
if (rhs.is_fully_const()) {
continue;
}
if (!lhs.is_chunk()) {
if (lhs.chunks().size() != rhs.chunks().size()) {
auto rit = rhs.chunks().rbegin();
long unsigned rhsSize = 0;
while (rit != rhs.chunks().rend()) {
RTLIL::SigSpec sub_rhs = *rit;
if (sub_rhs.is_fully_const()) {
rhsSize += (sub_rhs.as_chunk()).width;
} else {
rhsSize++;
}
rit++;
}
if (lhs.chunks().size() != rhsSize) {
continue;
}
}
auto lit = lhs.chunks().rbegin();
auto rit = rhs.chunks().rbegin();
while (rit != rhs.chunks().rend()) {
RTLIL::SigSpec sub_lhs = *lit;
RTLIL::SigSpec sub_rhs = *rit;
if (sub_rhs.is_fully_const()) {
int constSize = (sub_rhs.as_chunk()).width;
while (constSize--) {
lit++;
}
rit++;
continue;
}
lhsSig2rhsSig[sub_lhs] = sub_rhs;
lit++;
rit++;
}
} else {
lhsSig2rhsSig[lhs] = rhs;
}
}
}

std::string_view rtrim_until(std::string_view str, char c)
{
auto pos = str.rfind(c);
if (pos != std::string_view::npos)
str = str.substr(0, pos);
return str;
}

std::string id2String(RTLIL::IdString internal_id)
{
const char *str = internal_id.c_str();
std::string result = str;
return result;
}

std::string replaceAll(std::string_view str, std::string_view from, std::string_view to)
{
size_t start_pos = 0;
std::string result(str);
while ((start_pos = result.find(from, start_pos)) != std::string::npos) {
result.replace(start_pos, from.length(), to);
start_pos += to.length(); // Handles case where 'to' is a substr of 'from'
}
return result;
}

struct SplitNetlist : public ScriptPass {
SplitNetlist()
: ScriptPass("splitnetlist", "Splits a netlist into multiple modules using transitive fanin grouping. \
The output names that belong in the same logical cluster have to have the same prefix: <prefix>_<name>")
{
}
void script() {}

void execute(std::vector<std::string>, RTLIL::Design *design) override
{
if (design == nullptr) {
log_error("No design object");
return;
}
// Precompute cell output sigspec to cell map
dict<RTLIL::SigSpec, std::set<Cell *> *> sig2CellsInFanin;
sigCellDrivers(design, sig2CellsInFanin);
// Precompute lhs to rhs sigspec map
dict<RTLIL::SigSpec, RTLIL::SigSpec> lhsSig2RhsSig;
lhs2rhs(design, lhsSig2RhsSig);
// Struct representing a cluster
typedef struct CellsAndSigs {
std::set<Cell *> visitedCells;
std::set<RTLIL::SigSpec> visitedSigSpec;
} CellsAndSigs;
// Cluster mapped by prefix
typedef std::map<std::string, CellsAndSigs> CellName_ObjectMap;
CellName_ObjectMap cellName_ObjectMap;
// Record logic cone by output sharing the same prefix
for (auto wire : design->top_module()->wires()) {
if (!wire->port_output)
continue;
std::string output_port_name = wire->name.c_str();
std::string_view po_prefix = rtrim_until(std::string_view(output_port_name), '_');
std::set<Cell *> visitedCells;
std::set<RTLIL::SigSpec> visitedSigSpec;
RTLIL::SigSpec actual = wire;
// Visit the output sigspec
recordTransFanin(actual, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
// Visit the output sigspec bits
for (int i = 0; i < actual.size(); i++) {
SigSpec bit_sig = actual.extract(i, 1);
recordTransFanin(bit_sig, sig2CellsInFanin, lhsSig2RhsSig, visitedCells, visitedSigSpec);
}
// Record the visited objects in the corresponding cluster
CellName_ObjectMap::iterator itr = cellName_ObjectMap.find(std::string(po_prefix));
if (itr == cellName_ObjectMap.end()) {
CellsAndSigs components;
for (auto cell : visitedCells) {
components.visitedCells.insert(cell);
}
for (auto sig : visitedSigSpec) {
components.visitedSigSpec.insert(sig);
}
cellName_ObjectMap.emplace(std::string(po_prefix), components);
} else {
CellsAndSigs &components = itr->second;
for (auto cell : visitedCells) {
components.visitedCells.insert(cell);
}
for (auto sig : visitedSigSpec) {
components.visitedSigSpec.insert(sig);
}
}
}
// Create submod attributes for the submod command
for (CellName_ObjectMap::iterator itr = cellName_ObjectMap.begin(); itr != cellName_ObjectMap.end(); itr++) {
// std::cout << "Cluster name: " << itr->first << std::endl;
CellsAndSigs &components = itr->second;
for (auto cell : components.visitedCells) {
cell->set_string_attribute(RTLIL::escape_id("submod"), itr->first);
// std::cout << " CELL: " << cell->name.c_str() << std::endl;
}
// for (auto sigspec : components.visitedSigSpec) {
// std::cout << " SIG: " << SigName(sigspec) << std::endl;
// }
// std::cout << std::endl;
}
// Execute the submod command
Pass::call(design, "submod -copy");
}
} SplitNetlist;

PRIVATE_NAMESPACE_END
5 changes: 3 additions & 2 deletions passes/sat/sim.cc
Original file line number Diff line number Diff line change
Expand Up @@ -2355,8 +2355,7 @@ struct VCDWriter : public OutputWriter
}

if (!worker->timescale.empty())
vcdfile << stringf("$timescale %s $end\n", worker->timescale.c_str());

vcdfile << stringf("$timescale 1%s $end\n", worker->timescale.c_str());
worker->top->write_output_header(
[this](IdString name) { vcdfile << stringf("$scope module %s $end\n", log_id(name)); },
[this]() { vcdfile << stringf("$upscope $end\n");},
Expand Down Expand Up @@ -2500,6 +2499,8 @@ struct AnnotateActivity : public OutputWriter {
SignalActivityDataMap::iterator itr = dataMap.find(clk);
std::vector<uint32_t> &clktoggleCounts = itr->second.toggleCounts;
double clk_period = real_timescale * (double)max_time / (clktoggleCounts[0] / 2);
double frequency = 1 / clk_period;
worker->top->module->set_string_attribute("$FREQUENCY", std::to_string(frequency));
if (debug) {
std::cout << "Clock toggle count: " << clktoggleCounts[0] << "\n";
std::cout << "Max time: " << max_time << "\n";
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