abc/src/opt/rrr/rrrPartitioner.h

345 lines
10 KiB
C++

#pragma once
#include <utility>
#include <map>
#include <tuple>
#include <random>
#include "rrrParameter.h"
#include "rrrUtils.h"
ABC_NAMESPACE_CXX_HEADER_START
namespace rrr {
template <typename Ntk>
class Partitioner {
private:
// pointer to network
Ntk *pNtk;
// parameters
int nVerbose;
int nPartitionSize;
int nPartitionSizeMin;
std::string strVerbosePrefix;
// data
std::map<Ntk *, std::tuple<std::set<int>, std::vector<int>, std::vector<bool>, std::vector<int>>> mSubNtk2Io;
std::set<int> sBlocked;
std::vector<bool> vFailed;
// print
template<typename... Args>
void Print(int nVerboseLevel, Args... args);
// subroutines
void GetIo(std::set<int> const &sNodes, std::set<int> &sInputs, std::set<int> &sOutputs);
std::set<int> GetFanouts(std::set<int> const &sNodes, std::set<int> const &sOutputs);
std::set<int> GetUnblockedNeighborsAndInners(int id, int nRadius);
Ntk *ExtractDisjoint(int id);
public:
// constructors
Partitioner(Parameter const *pPar);
void AssignNetwork(Ntk *pNtk);
// APIs
Ntk *Extract(int iSeed);
void Insert(Ntk *pSubNtk);
};
/* {{{ Print */
template <typename Ntk>
template <typename... Args>
inline void Partitioner<Ntk>::Print(int nVerboseLevel, Args... args) {
if(nVerbose > nVerboseLevel) {
std::cout << strVerbosePrefix;
for(int i = 0; i < nVerboseLevel; i++) {
std::cout << "\t";
}
PrintNext(std::cout, args...);
std::cout << std::endl;
}
}
/* }}} */
/* {{{ Subroutines */
template <typename Ntk>
void Partitioner<Ntk>::GetIo(std::set<int> const &sNodes, std::set<int> &sInputs, std::set<int> &sOutputs) {
sInputs.clear();
sOutputs.clear();
for(int id: sNodes) {
pNtk->ForEachFanin(id, [&](int fi) {
if(!sNodes.count(fi)) {
sInputs.insert(fi);
}
});
bool fOutput = false;
pNtk->ForEachFanout(id, true, [&](int fo) {
if(!sNodes.count(fo)) {
fOutput = true;
}
});
if(fOutput) {
sOutputs.insert(id);
}
}
}
template <typename Ntk>
std::set<int> Partitioner<Ntk>::GetFanouts(std::set<int> const &sNodes, std::set<int> const &sOutputs) {
std::set<int> sFanouts;
for(int id: sOutputs) {
pNtk->ForEachFanout(id, false, [&](int fo) {
if(!sNodes.count(fo)) {
sFanouts.insert(fo);
}
});
}
return sFanouts;
}
template <typename Ntk>
std::set<int> Partitioner<Ntk>::GetUnblockedNeighborsAndInners(int id, int nRadius) {
// return empty set on failure
// get neighbors
std::vector<int> vNodes = pNtk->GetNeighbors(id, false, nRadius);
vNodes.push_back(id);
std::set<int> sNodes(vNodes.begin(), vNodes.end());
Print(2, "radius", NS(), nRadius, ":", "size =", int_size(sNodes));
// remove nodes that are already blocked
for(std::set<int>::iterator it = sNodes.begin(); it != sNodes.end();) {
if(sBlocked.count(*it)) {
it = sNodes.erase(it);
} else {
it++;
}
}
Print(2, "unblocked:", "size =", int_size(sNodes));
if(int_size(sNodes) > nPartitionSize) {
// too large
return std::set<int>();
}
// get tentative partition IO
std::set<int> sInputs, sOutputs;
GetIo(sNodes, sInputs, sOutputs);
Print(3, "nodes:", sNodes);
Print(3, "inputs:", sInputs);
Print(3, "outputs:", sOutputs);
// include inner nodes
std::set<int> sFanouts = GetFanouts(sNodes, sOutputs);
std::vector<int> vInners = pNtk->GetInners(sFanouts, sInputs);
while(!vInners.empty()) {
Print(2, "inner size =", int_size(vInners));
// check overlap
for(int id: vInners) {
if(sBlocked.count(id)) {
// overlapped
return std::set<int>();
}
}
// expand
sNodes.insert(vInners.begin(), vInners.end());
Print(2, "expanded:", "size =", int_size(sNodes));
if(int_size(sNodes) > nPartitionSize) {
// too large
return std::set<int>();
}
GetIo(sNodes, sInputs, sOutputs);
Print(3, "nodes:", sNodes);
Print(3, "inputs:", sInputs);
Print(3, "outputs:", sOutputs);
// recompute fanouts
sFanouts = GetFanouts(sNodes, sOutputs);
vInners = pNtk->GetInners(sFanouts, sInputs);
}
return sNodes;
}
template <typename Ntk>
Ntk *Partitioner<Ntk>::ExtractDisjoint(int id) {
// collect neighbor
assert(!sBlocked.count(id));
int nRadius = 1;
std::set<int> sNodes = GetUnblockedNeighborsAndInners(id, nRadius);
Print(1, "radius", NS(), nRadius, ":", "size =", int_size(sNodes));
if(sNodes.empty()) {
return NULL;
}
std::set<int> sNodesNew = GetUnblockedNeighborsAndInners(id, nRadius + 1);
Print(1, "radius", NS(), nRadius + 1, ":", "size =", int_size(sNodesNew));
// gradually increase radius until it hits partition size limit
while(!sNodesNew.empty()) {
if(int_size(sNodes) == int_size(sNodesNew)) { // likely already maximum
break;
}
sNodes = sNodesNew;
nRadius++;
sNodesNew = GetUnblockedNeighborsAndInners(id, nRadius + 1);
Print(1, "radius", NS(), nRadius + 1, ":", "size =", int_size(sNodesNew));
}
if(int_size(sNodes) < nPartitionSizeMin) {
// too small
return NULL;
}
std::set<int> sInputs, sOutputs;
GetIo(sNodes, sInputs, sOutputs);
/* fall back method by removing TFI of outputs reachable to inputs
if(!vInners.empty()) {
for(int id: sOutputs) {
if(!sNodes.count(id)) { // already removed
continue;
}
std::set<int> sFanouts = GetFanouts(sNodes, sOutputs);
if(pNtk->IsReachable(sFanouts, sInputs)) {
Print(2, "node", id, "is reachable");
sNodes.erase(id);
pNtk->ForEachTfiEnd(id, sInputs, [&](int fi) {
int r = sNodes.erase(fi);
assert(r);
});
Print(1, "shrinking:", "size =", int_size(sNodes));
if(int_size(sNodes) < nPartitionSizeMin) {
// too small
return NULL;
}
// recompute inputs
sInputs.clear();
for(int id: sNodes) {
pNtk->ForEachFanin(id, [&](int fi) {
if(!sNodes.count(fi)) {
sInputs.insert(fi);
}
});
}
Print(3, "nodes:", sNodes);
Print(3, "inputs:", sInputs);
}
}
// recompute outputs
for(std::set<int>::iterator it = sOutputs.begin(); it != sOutputs.end();) {
if(!sNodes.count(*it)) {
it = sOutputs.erase(it);
} else {
it++;
}
}
Print(3, "new outputs:", sOutputs);
}
*/
// ensure outputs of both partitions do not reach each other's inputs at the same time
for(auto const &entry: mSubNtk2Io) {
if(!pNtk->IsReachable(sOutputs, std::get<1>(entry.second))) {
continue;
}
if(!pNtk->IsReachable(std::get<3>(entry.second), sInputs)) {
continue;
}
// if(nVerbose) {
// std::cout << "POTENTIAL LOOPS" << std::endl;
// }
return NULL;
}
assert(int_size(sNodes) <= nPartitionSize);
assert(int_size(sNodes) >= nPartitionSizeMin);
// extract by inputs, internals, and outputs (no checks needed in ntk side)
std::vector<int> vInputs(sInputs.begin(), sInputs.end());
std::vector<int> vOutputs(sOutputs.begin(), sOutputs.end());
Ntk *pSubNtk = pNtk->Extract(sNodes, vInputs, vOutputs);
// return subntk to be modified, while remember IOs
for(int id: sNodes) {
sBlocked.insert(id);
}
mSubNtk2Io.emplace(pSubNtk, std::make_tuple(std::move(sNodes), std::move(vInputs), std::vector<bool>(vInputs.size()), std::move(vOutputs)));
return pSubNtk;
}
/* }}} */
/* {{{ Constructors */
template <typename Ntk>
Partitioner<Ntk>::Partitioner(Parameter const *pPar) :
nVerbose(pPar->nPartitionerVerbose),
nPartitionSize(pPar->nPartitionSize),
nPartitionSizeMin(pPar->nPartitionSizeMin) {
}
template <typename Ntk>
void Partitioner<Ntk>::AssignNetwork(Ntk *pNtk_) {
pNtk = pNtk_;
assert(mSubNtk2Io.empty());
assert(sBlocked.empty());
vFailed.clear();
}
/* }}} */
/* {{{ APIs */
template <typename Ntk>
Ntk *Partitioner<Ntk>::Extract(int iSeed) {
// pick a center node from candidates that do not belong to any other ongoing partitions
vFailed.resize(pNtk->GetNumNodes());
std::mt19937 rng(iSeed);
std::vector<int> vInts = pNtk->GetInts();
std::shuffle(vInts.begin(), vInts.end(), rng);
for(int i = 0; i < int_size(vInts); i++) {
int id = vInts[i];
if(vFailed[id]) {
continue;
}
if(!sBlocked.count(id)) {
Print(0, "try partitioning with node", id, "(", i, "/", int_size(vInts), ")");
Ntk *pSubNtk = ExtractDisjoint(id);
if(pSubNtk) {
return pSubNtk;
}
}
vFailed[id] = true;
}
return NULL;
}
template <typename Ntk>
void Partitioner<Ntk>::Insert(Ntk *pSubNtk) {
for(int i: std::get<0>(mSubNtk2Io[pSubNtk])) {
sBlocked.erase(i);
}
std::pair<std::vector<int>, std::vector<bool>> vNewSignals = pNtk->Insert(pSubNtk, std::get<1>(mSubNtk2Io[pSubNtk]), std::get<2>(mSubNtk2Io[pSubNtk]), std::get<3>(mSubNtk2Io[pSubNtk]));
std::vector<int> &vOldOutputs = std::get<3>(mSubNtk2Io[pSubNtk]);
std::vector<int> &vNewOutputs = vNewSignals.first;
std::vector<bool> &vNewCompls = vNewSignals.second;
// need to remap updated outputs that are used as inputs in other partitions
std::map<int, int> mOutput2Idx;
for(int idx = 0; idx < int_size(vOldOutputs); idx++) {
mOutput2Idx[vOldOutputs[idx]] = idx;
}
for(auto &entry: mSubNtk2Io) {
if(entry.first != pSubNtk) {
std::vector<int> &vInputs = std::get<1>(entry.second);
std::vector<bool> &vCompls = std::get<2>(entry.second);
for(int i = 0; i < int_size(vInputs); i++) {
if(mOutput2Idx.count(vInputs[i])) {
int idx = mOutput2Idx[vInputs[i]];
vInputs[i] = vNewOutputs[idx];
vCompls[i] = vCompls[i] ^ vNewCompls[idx];
}
}
}
}
delete pSubNtk;
mSubNtk2Io.erase(pSubNtk);
vFailed.clear(); // clear, there isn't really a way to track
}
/* }}} */
}
ABC_NAMESPACE_CXX_HEADER_END