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#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <array>
#include <bitset>
#include <functional>
#include <iostream>
#include <list>
#include <map>
#include <set>
#include <thread>
#include <sys/mman.h>
#include "packed_array.hpp"
using namespace std;
#ifndef BIT_WIDTH
#define BIT_WIDTH 31
#endif
typedef uint64_t State;
const State logState = BIT_WIDTH;
const State maxState = (State) 1 << logState;
// # of bits of largest memory fetch issued; machine-specific; used to
// garantue that sub-byte sized access of different threads never
// address the same word
const uint maxWordSize = 128;
bitset<8> rule(110);
State update(State s) {
State r(0);
bitset<logState> b(s);
for (unsigned i=0; i<logState; i++)
r |= rule[1 * b[(i + logState - 1) % logState]
+ 2 * b[i]
+ 4 * b[(i + 1) % logState]] << i;
return r;
}
typedef packed_array<State, maxState, BIT_WIDTH> Trans;
void iterState(function<void(int)> f, bool parallel = false) {
int numThreads=1;
if (parallel) {
numThreads = min((State) thread::hardware_concurrency(),
maxState / maxWordSize);
}
list<thread*> tasks;
for (int t=0; t<numThreads; t++) {
tasks.push_front(new thread([=]{
for (State s = maxState / numThreads * t;
s < ((t == numThreads - 1) ? maxState : (maxState / numThreads * (t+1)));
s++)
f(s);
}));
}
for (; !tasks.empty(); tasks.front()->join(), delete tasks.front(), tasks.pop_front());
}
void iterTrans(int times, function<void(int)> f, char *msg = nullptr, bool parallel = false) {
if (msg) cerr << msg << times << " left \r";
while (times--) {
iterState(f, parallel);
if (msg) cerr << msg << times << " left \r";
}
if (msg) cerr << " \r";
}
void init(Trans &t) {
iterState([&](int s) {
t[s] = update(s); }, true);
}
void findCycle(Trans &t, Trans &c, bitset<maxState> &reachable) {
// compute reachability
iterState([&](int s) {
reachable[t[s]] = 1;
}, true);
// forward to t=maxState; now every state is in a cycle
iterTrans(logState, [&](int s) {
t[s] = t[t[s]]; }, (char*) "fwd time: ");
// compute loop id (lowest occuring state no): go through the loop again and
// record the lowest occuring state number
iterState([&](int s) {
c[s] = t[s]; }, true);
iterTrans(logState, [&](int s) {
c[s] = min<State>(c[s], c[t[s]]);
t[s] = t[t[s]]; }, (char*) "cycles: ");
}
void cycleStat(Trans &c, bitset<maxState> &reachable) {
struct Stat {
State basin, len, eden, minState;
Stat() : basin(0), len(0), eden(0), minState(maxState) {}
};
map<State, Stat> cyc;
// How big is the basin of attraction?
// How many garden of eden states does it contain?
iterState([&](int s) {
cyc[c[s]].basin++;
if (!reachable[s])
cyc[c[s]].eden++;
});
// how long is the cycle, what is the actual minimal state
for (auto i : cyc) {
Stat &s = cyc[i.first];
State cur, start;
cur = start = c[i.first];
do {
s.len++;
s.minState = min(s.minState, cur);
cur=update(cur);
} while (cur != start);
}
// find duplicates cycles (only bitshifted)
auto canonize = [](State s) {
State cs = s;
for (State i=0; i<logState; i++)
cs = min(cs, (((s<<i) | (s>>(logState-i))) & (maxState - 1)));
return cs;
};
map<State, set<State>> ccyc;
for (auto i : cyc) {
ccyc[canonize(i.second.minState)].insert(i.first);
}
// print it
for (auto i : ccyc) {
Stat &s = cyc[*(i.second.begin())];
cout << bitset<logState>(i.first) << "\t"
<< i.second.size() << "\t"
<< s.len << "\t"
<< s.basin << "\t"
<< s.eden << "\t"
<< i.first << endl;
}
}
void print(Trans &t) {
for (auto s : t)
cout << bitset<logState>(s) << endl;
}
void printTraj(State s, int count) {
while (count--) {
cout << bitset<logState>(s) << endl;
s = update(s);
}
}
template<typename T>
T* mmalloc() {
void *p = MAP_FAILED;
for (auto flag : {MAP_POPULATE | MAP_HUGETLB, MAP_POPULATE, 0})
if (p == MAP_FAILED)
p = mmap(NULL, sizeof(Trans), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | flag, -1, 0);
assert(p != MAP_FAILED);
return (T*) p;
}
int main(int argc, char **argv) {
assert(argc >= 2);
rule = atoi(argv[1]);
if (!strcmp(argv[2], "traj")) {
assert(argc == 5);
printTraj(atoi(argv[3]), atoi(argv[4]));
}
if (!strcmp(argv[2], "cycle")) {
Trans *t = mmalloc<Trans>(),
*c = mmalloc<Trans>();
bitset<maxState> *r = new bitset<maxState>(0);
init(*t);
findCycle(*t, *c, *r);
cycleStat(*c, *r);
}
return 0;
}
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