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#include <array>
#include <map>
#include <string>
#include <gecode/driver.hh>
#include <gecode/int.hh>
#include <gecode/gist.hh>
#include <gecode/minimodel.hh>
using namespace std;
using namespace Gecode;
string S() {
return "";
}
template<typename T, typename... Ts>
string S(T v, Ts... vs) {
stringstream ss;
ss << v << S(vs...);
return ss.str();
}
struct Op {
string inst;
IntVar *v;
int delay;
};
struct Demultiplexer : public Space {
IntVarArray op_times;
array<Op, 17> ops;
uint opCount;
Demultiplexer(vector<bool> bits)
: op_times(*this, 17, 0, 16)
{
/// post the problem (the instructions and their temporal
/// dependencies)
// only one op per time slice
distinct(*this, op_times);
// the final jump
auto &jump = op(2, " ijmp");
at(jump, 15);
// rising flanks
for (uint i=0; i<bits.size(); i++) {
auto &rise = op(1, S(" out %", i, ", 1"));
auto &fall = op(1, S(" out %", i, ", 0"));
if (bits[i]) { after(rise, fall, 4, 6 ); }
else { after(rise, fall, 8, 13); }
after(fall, jump);
at(rise, i);
}
// load next jump location
after(op(2, " ld %ZH, %[data_ptr]+"), jump);
// add nops until we have enough instructions to fill the time
// slice
while (opCount < ops.size())
op(1, " nop");
/// branching
branch(*this, op_times, INT_VAR_SIZE_MIN, INT_VAL_MIN);
}
Op& op(int delay, string inst) {
Op &o = ops[opCount];
o.inst = inst;
o.v = &(op_times[opCount]);
o.delay = delay;
opCount++;
// add pseudo-op to encode instructions that take more than one
// cycle
if (delay > 1) {
auto nextOp = op(delay - 1, "; 1 clock cycle delay");
rel(*this, *(o.v) + 1 == *(nextOp.v));
}
return o;
}
/// helper for constraint formulation
void after(Op& pre, Op& post, int delay_min=0, int delay_max=-1) {
rel(*this, *(pre.v) + pre.delay + delay_min <= *(post.v));
if (delay_max >= 0)
rel(*this, *(pre.v) + pre.delay + delay_max >= *(post.v));
}
void at(Op& op, int time_min, int time_max=-1) {
if (time_max == -1)
time_max = time_min;
rel(*this, *(op.v) >= time_min);
rel(*this, *(op.v) <= time_max);
}
/// return resulting instruction stream
string print() {
stringstream ss;
print(ss, false);
return ss.str();
}
/// gecode boilerplate
Demultiplexer(bool share, Demultiplexer &o)
: Space(share, o),
ops(o.ops),
opCount(o.opCount)
{
op_times.update(*this, share, o.op_times);
}
virtual Space* copy(bool share) {
return new Demultiplexer(share, *this);
}
void print(ostream &o, bool printTimes=true) const {
multimap<int, int> timedOps;
for (uint i=0; i<ops.size(); i++)
timedOps.insert(make_pair(op_times[i].min(), i));
for (auto i : timedOps) {
auto &op = ops[i.second];
o << op.inst;
if (printTimes)
o << "\t; " << *(op.v);
o << endl;
}
}
};
int main(int argc, char **argv) {
Demultiplexer *d = new Demultiplexer({0,1,0,1,0});
// Gist::Print<Demultiplexer> gp("print solution");
// Gist::Options go;
// go.inspect.click(&gp);
// Gist::dfs(d, go);
DFS<Demultiplexer> e(d);
delete d;
d = e.next();
if (d) {
cout << d->print();
delete d;
}else{
cerr << "no instruction sequence found";
}
}
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