portelli/Grid
1
0
Fork 0
mirror of https://github.com/paboyle/Grid.git synced 2024-09-20 17:25:37 +01:00
Code Releases Activity
01480da0a8
Grid/lib/lattice/Lattice_rng.h

397 lines
12 KiB
C++
Raw Blame History

/*************************************************************************************
Grid physics library, www.github.com/paboyle/Grid
Source file: ./lib/lattice/Lattice_rng.h
Copyright (C) 2015
Author: Peter Boyle <paboyle@ph.ed.ac.uk>
Author: paboyle <paboyle@ph.ed.ac.uk>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
See the full license in the file "LICENSE" in the top level distribution directory
*************************************************************************************/
/* END LEGAL */
#ifndef GRID_LATTICE_RNG_H
#define GRID_LATTICE_RNG_H
#include <random>
namespace Grid {
//////////////////////////////////////////////////////////////
// Allow the RNG state to be less dense than the fine grid
//////////////////////////////////////////////////////////////
inline int RNGfillable(GridBase *coarse,GridBase *fine)
{
int rngdims = coarse->_ndimension;
// trivially extended in higher dims, with locality guaranteeing RNG state is local to node
int lowerdims = fine->_ndimension - coarse->_ndimension;
assert(lowerdims >= 0);
for(int d=0;d<lowerdims;d++){
assert(fine->_simd_layout[d]==1);
assert(fine->_processors[d]==1);
}
int multiplicity=1;
for(int d=0;d<lowerdims;d++){
multiplicity=multiplicity*fine->_rdimensions[d];
}
// local and global volumes subdivide cleanly after SIMDization
for(int d=0;d<rngdims;d++){
int fd= d+lowerdims;
assert(coarse->_processors[d] == fine->_processors[fd]);
assert(coarse->_simd_layout[d] == fine->_simd_layout[fd]);
assert(((fine->_rdimensions[fd] / coarse->_rdimensions[d])* coarse->_rdimensions[d])==fine->_rdimensions[fd]);
multiplicity = multiplicity *fine->_rdimensions[fd] / coarse->_rdimensions[d];
}
return multiplicity;
}
// Wrap seed_seq to give common interface with random_device
class fixedSeed {
public:
typedef std::seed_seq::result_type result_type;
std::seed_seq src;
fixedSeed(const std::vector<int> &seeds) : src(seeds.begin(),seeds.end()) {};
result_type operator () (void){
std::vector<result_type> list(1);
src.generate(list.begin(),list.end());
return list[0];
}
};
// real scalars are one component
template<class scalar,class distribution,class generator> void fillScalar(scalar &s,distribution &dist,generator & gen)
{
s=dist(gen);
}
template<class distribution,class generator> void fillScalar(ComplexF &s,distribution &dist, generator &gen)
{
s=ComplexF(dist(gen),dist(gen));
}
template<class distribution,class generator> void fillScalar(ComplexD &s,distribution &dist,generator &gen)
{
s=ComplexD(dist(gen),dist(gen));
}
class GridRNGbase {
public:
int _seeded;
// One generator per site.
// Uniform and Gaussian distributions from these generators.
#ifdef RNG_RANLUX
typedef uint64_t RngStateType;
typedef std::ranlux48 RngEngine;
static const int RngStateCount = 15;
#else
typedef std::mt19937 RngEngine;
typedef uint32_t RngStateType;
static const int RngStateCount = std::mt19937::state_size;
#endif
std::vector<RngEngine> _generators;
std::vector<std::uniform_real_distribution<RealD>> _uniform;
std::vector<std::normal_distribution<RealD>> _gaussian;
std::vector<std::discrete_distribution<int32_t>> _bernoulli;
void GetState(std::vector<RngStateType> & saved,int gen) {
saved.resize(RngStateCount);
std::stringstream ss;
ss<<_generators[gen];
ss.seekg(0,ss.beg);
for(int i=0;i<RngStateCount;i++){
ss>>saved[i];
}
}
void SetState(std::vector<RngStateType> & saved,int gen){
assert(saved.size()==RngStateCount);
std::stringstream ss;
for(int i=0;i<RngStateCount;i++){
ss<< saved[i]<<" ";
}
ss.seekg(0,ss.beg);
ss>>_generators[gen];
}
};
class GridSerialRNG : public GridRNGbase {
public:
// FIXME ... do we require lockstep draws of randoms
// from all nodes keeping seeds consistent.
// place a barrier/broadcast in the fill routine
template<class source> void Seed(source &src)
{
typename source::result_type init = src();
CartesianCommunicator::BroadcastWorld(0,(void *)&init,sizeof(init));
_generators[0] = RngEngine(init);
_seeded=1;
}
GridSerialRNG() : GridRNGbase() {
_generators.resize(1);
_uniform.resize(1,std::uniform_real_distribution<RealD>{0,1});
_gaussian.resize(1,std::normal_distribution<RealD>(0.0,1.0) );
_bernoulli.resize(1,std::discrete_distribution<int32_t>{1,1});
_seeded=0;
}
template <class sobj,class distribution> inline void fill(sobj &l,std::vector<distribution> &dist){
typedef typename sobj::scalar_type scalar_type;
int words = sizeof(sobj)/sizeof(scalar_type);
scalar_type *buf = (scalar_type *) & l;
dist[0].reset();
for(int idx=0;idx<words;idx++){
fillScalar(buf[idx],dist[0],_generators[0]);
}
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
};
template <class distribution> inline void fill(ComplexF &l,std::vector<distribution> &dist){
dist[0].reset();
fillScalar(l,dist[0],_generators[0]);
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
template <class distribution> inline void fill(ComplexD &l,std::vector<distribution> &dist){
dist[0].reset();
fillScalar(l,dist[0],_generators[0]);
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
template <class distribution> inline void fill(RealF &l,std::vector<distribution> &dist){
dist[0].reset();
fillScalar(l,dist[0],_generators[0]);
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
template <class distribution> inline void fill(RealD &l,std::vector<distribution> &dist){
dist[0].reset();
fillScalar(l,dist[0],_generators[0]);
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
// vector fill
template <class distribution> inline void fill(vComplexF &l,std::vector<distribution> &dist){
RealF *pointer=(RealF *)&l;
dist[0].reset();
for(int i=0;i<2*vComplexF::Nsimd();i++){
fillScalar(pointer[i],dist[0],_generators[0]);
}
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
template <class distribution> inline void fill(vComplexD &l,std::vector<distribution> &dist){
RealD *pointer=(RealD *)&l;
dist[0].reset();
for(int i=0;i<2*vComplexD::Nsimd();i++){
fillScalar(pointer[i],dist[0],_generators[0]);
}
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
template <class distribution> inline void fill(vRealF &l,std::vector<distribution> &dist){
RealF *pointer=(RealF *)&l;
dist[0].reset();
for(int i=0;i<vRealF::Nsimd();i++){
fillScalar(pointer[i],dist[0],_generators[0]);
}
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
template <class distribution> inline void fill(vRealD &l,std::vector<distribution> &dist){
RealD *pointer=(RealD *)&l;
dist[0].reset();
for(int i=0;i<vRealD::Nsimd();i++){
fillScalar(pointer[i],dist[0],_generators[0]);
}
CartesianCommunicator::BroadcastWorld(0,(void *)&l,sizeof(l));
}
void SeedRandomDevice(void){
std::random_device rd;
Seed(rd);
}
void SeedFixedIntegers(const std::vector<int> &seeds){
fixedSeed src(seeds);
Seed(src);
}
};
class GridParallelRNG : public GridRNGbase {
public:
GridBase *_grid;
int _vol;
int generator_idx(int os,int is){
return is*_grid->oSites()+os;
}
GridParallelRNG(GridBase *grid) : GridRNGbase() {
_grid=grid;
_vol =_grid->iSites()*_grid->oSites();
_generators.resize(_vol);
_uniform.resize(_vol,std::uniform_real_distribution<RealD>{0,1});
_gaussian.resize(_vol,std::normal_distribution<RealD>(0.0,1.0) );
_bernoulli.resize(_vol,std::discrete_distribution<int32_t>{1,1});
_seeded=0;
}
// This loop could be made faster to avoid the Ahmdahl by
// i) seed generators on each timeslice, for x=y=z=0;
// ii) seed generators on each z for x=y=0
// iii)seed generators on each y,z for x=0
// iv) seed generators on each y,z,x
// made possible by physical indexing.
template<class source> void Seed(source &src)
{
std::vector<int> gcoor;
int gsites = _grid->_gsites;
typename source::result_type init = src();
RngEngine pseeder(init);
std::uniform_int_distribution<uint64_t> ui;
for(int gidx=0;gidx<gsites;gidx++){
int rank,o_idx,i_idx;
_grid->GlobalIndexToGlobalCoor(gidx,gcoor);
_grid->GlobalCoorToRankIndex(rank,o_idx,i_idx,gcoor);
int l_idx=generator_idx(o_idx,i_idx);
const int num_rand_seed=16;
std::vector<int> site_seeds(num_rand_seed);
for(int i=0;i<site_seeds.size();i++){
site_seeds[i]= ui(pseeder);
}
_grid->Broadcast(0,(void *)&site_seeds[0],sizeof(int)*site_seeds.size());
if( rank == _grid->ThisRank() ){
fixedSeed ssrc(site_seeds);
typename source::result_type sinit = ssrc();
_generators[l_idx] = RngEngine(sinit);
}
}
_seeded=1;
}
//FIXME implement generic IO and create state save/restore
//void SaveState(const std::string<char> &file);
//void LoadState(const std::string<char> &file);
template <class vobj, class distribution>
inline void fill(Lattice<vobj> &l, std::vector<distribution> &dist) {
typedef typename vobj::scalar_object scalar_object;
typedef typename vobj::scalar_type scalar_type;
typedef typename vobj::vector_type vector_type;
int multiplicity = RNGfillable(_grid, l._grid);
int Nsimd = _grid->Nsimd();
int osites = _grid->oSites();
int words = sizeof(scalar_object) / sizeof(scalar_type);
PARALLEL_FOR_LOOP
for (int ss = 0; ss < osites; ss++) {
std::vector<scalar_object> buf(Nsimd);
for (int m = 0; m < multiplicity;
m++) { // Draw from same generator multiplicity times
int sm = multiplicity * ss +
m; // Maps the generator site to the fine site
for (int si = 0; si < Nsimd; si++) {
int gdx = generator_idx(ss, si); // index of generator state
scalar_type *pointer = (scalar_type *)&buf[si];
dist[gdx].reset();
for (int idx = 0; idx < words; idx++) {
fillScalar(pointer[idx], dist[gdx], _generators[gdx]);
}
}
// merge into SIMD lanes
merge(l._odata[sm], buf);
}
}
};
void SeedRandomDevice(void) {
std::random_device rd;
Seed(rd);
}
void SeedFixedIntegers(const std::vector<int> &seeds) {
fixedSeed src(seeds);
Seed(src);
}
};
template <class vobj> inline void random(GridParallelRNG &rng,Lattice<vobj> &l){
rng.fill(l,rng._uniform);
}
template <class vobj> inline void gaussian(GridParallelRNG &rng,Lattice<vobj> &l){
rng.fill(l,rng._gaussian);
}
template <class vobj> inline void bernoulli(GridParallelRNG &rng,Lattice<vobj> &l){
rng.fill(l,rng._bernoulli);
}
template <class sobj> inline void random(GridSerialRNG &rng,sobj &l){
rng.fill(l,rng._uniform);
}
template <class sobj> inline void gaussian(GridSerialRNG &rng,sobj &l){
rng.fill(l,rng._gaussian);
}
template <class sobj> inline void bernoulli(GridSerialRNG &rng,sobj &l){
rng.fill(l,rng._bernoulli);
}
}
#endif
View Git Blame Copy Permalink