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#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdint.h>
#include <omp.h>
#include "../../support/common.h"
#include "../../support/graph.h"
#include "../../support/params.h"
#include "../../support/timer.h"
#include "../../support/utils.h"
int main(int argc, char** argv) {
// Process parameters
struct Params p = input_params(argc, argv);
// Initialize BFS data structures
PRINT_INFO(p.verbosity >= 1, "Reading graph %s", p.fileName);
struct COOGraph cooGraph = readCOOGraph(p.fileName);
PRINT_INFO(p.verbosity >= 1, " Graph has %d nodes and %d edges", cooGraph.numNodes, cooGraph.numEdges);
Timer timer;
for(int rep = 0; rep < 100; rep++) {
struct CSRGraph csrGraph = coo2csr(cooGraph);
uint32_t* nodeLevel = (uint32_t*) malloc(csrGraph.numNodes*sizeof(uint32_t));
uint32_t* nodeLevelRef = (uint32_t*) malloc(csrGraph.numNodes*sizeof(uint32_t));
for(uint32_t i = 0; i < csrGraph.numNodes; ++i) {
nodeLevel[i] = UINT32_MAX; // Unreachable
nodeLevelRef[i] = UINT32_MAX; // Unreachable
}
uint32_t srcNode = 0;
// Initialize frontier double buffers
uint32_t* buffer1 = (uint32_t*) malloc(csrGraph.numNodes*sizeof(uint32_t));
uint32_t* buffer2 = (uint32_t*) malloc(csrGraph.numNodes*sizeof(uint32_t));
uint32_t* prevFrontier = buffer1;
uint32_t* currFrontier = buffer2;
// Calculating result on CPU
startTimer(&timer, 0, 0);
nodeLevel[srcNode] = 0;
prevFrontier[0] = srcNode;
uint32_t numPrevFrontier = 1;
for(uint32_t level = 1; numPrevFrontier > 0; ++level) {
uint32_t numCurrFrontier = 0;
// Visit nodes in the previous frontier
#pragma omp parallel for
for(uint32_t i = 0; i < numPrevFrontier; ++i) {
uint32_t node = prevFrontier[i];
for(uint32_t edge = csrGraph.nodePtrs[node]; edge < csrGraph.nodePtrs[node + 1]; ++edge) {
uint32_t neighbor = csrGraph.neighborIdxs[edge];
uint32_t justVisited = 0;
#pragma omp critical
{
if(nodeLevel[neighbor] == UINT32_MAX) { // Node not previously visited
nodeLevel[neighbor] = level;
justVisited = 1;
}
}
if(justVisited) {
uint32_t currFrontierIdx;
#pragma omp critical
{
currFrontierIdx = numCurrFrontier++;
}
currFrontier[currFrontierIdx] = neighbor;
}
}
}
// Swap buffers
uint32_t* tmp = prevFrontier;
prevFrontier = currFrontier;
currFrontier = tmp;
numPrevFrontier = numCurrFrontier;
}
stopTimer(&timer, 0);
freeCSRGraph(csrGraph);
free(buffer1);
free(buffer2);
csrGraph = coo2csr(cooGraph);
srcNode = 0;
// Initialize frontier double buffers
buffer1 = (uint32_t*) malloc(csrGraph.numNodes*sizeof(uint32_t));
buffer2 = (uint32_t*) malloc(csrGraph.numNodes*sizeof(uint32_t));
prevFrontier = buffer1;
currFrontier = buffer2;
// Calculating result on CPU sequentially
startTimer(&timer, 1, 0);
nodeLevelRef[srcNode] = 0;
prevFrontier[0] = srcNode;
numPrevFrontier = 1;
for(uint32_t level = 1; numPrevFrontier > 0; ++level) {
uint32_t numCurrFrontier = 0;
// Visit nodes in the previous frontier
for(uint32_t i = 0; i < numPrevFrontier; ++i) {
uint32_t node = prevFrontier[i];
for(uint32_t edge = csrGraph.nodePtrs[node]; edge < csrGraph.nodePtrs[node + 1]; ++edge) {
uint32_t neighbor = csrGraph.neighborIdxs[edge];
uint32_t justVisited = 0;
if(nodeLevelRef[neighbor] == UINT32_MAX) { // Node not previously visited
nodeLevelRef[neighbor] = level;
justVisited = 1;
}
if(justVisited) {
uint32_t currFrontierIdx;
currFrontierIdx = numCurrFrontier++;
currFrontier[currFrontierIdx] = neighbor;
}
}
}
// Swap buffers
uint32_t* tmp = prevFrontier;
prevFrontier = currFrontier;
currFrontier = tmp;
numPrevFrontier = numCurrFrontier;
}
stopTimer(&timer, 1);
unsigned int nr_threads = 0;
#pragma omp parallel
#pragma omp atomic
nr_threads++;
// Verifying result
int isOK = 1;
for(uint32_t nodeIdx = 0; nodeIdx < csrGraph.numNodes; ++nodeIdx) {
if(nodeLevel[nodeIdx] != nodeLevelRef[nodeIdx]) {
PRINT_ERROR("Mismatch at node %u (CPU sequential result = level %u, CPU parallel result = level %u)", nodeIdx, nodeLevelRef[nodeIdx], nodeLevel[nodeIdx]);
isOK = 0;
}
}
if (isOK) {
printf("[::] n_threads=%d e_type=%s n_elements=%d "
"| throughput_cpu_ref_MBps=%f throughput_cpu_omp_MBps=%f\n",
nr_threads, "uint32_t", csrGraph.numNodes,
csrGraph.numNodes * sizeof(uint32_t) / timer.time[1],
csrGraph.numNodes * sizeof(uint32_t) / timer.time[0]);
printf("[::] n_threads=%d e_type=%s n_elements=%d "
"| throughput_cpu_ref_MOpps=%f throughput_cpu_omp_MOpps=%f\n",
nr_threads, "uint32_t", csrGraph.numNodes,
csrGraph.numNodes / timer.time[1],
csrGraph.numNodes / timer.time[0]);
printf("[::] n_threads=%d e_type=%s n_elements=%d |",
nr_threads, "uint32_t", csrGraph.numNodes);
printAll(&timer, 1);
}
freeCSRGraph(csrGraph);
free(nodeLevel);
free(nodeLevelRef);
free(buffer1);
free(buffer2);
}
// Deallocate data structures
freeCOOGraph(cooGraph);
return 0;
}
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