chundoong-lab-ta/SamsungDS22/submissions/HW2/yd99.park/mat_mul.cpp

68 lines
1.8 KiB
C++

#include "mat_mul.h"
#include <cstdlib>
#include <cstdio>
#include <pthread.h>
static float *A, *B, *C;
static int M, N, K;
static int num_threads;
#define min(a,b) ((a)>(b) ? (b) : (a))
static void* mat_mul_thread(void *data) {
// TODO: parallelize & optimize matrix multiplication
int pid = * (int *) data;
int slice = M / num_threads;
int start = pid * slice;
int end = pid == num_threads - 1 ? M : (pid + 1) * slice;
int i,j,k;
int kk;
float Aik;
int bs = 64;
for (kk = 0; kk < K; kk += bs) {
for (i = start; i < end; ++i) {
for (k = kk; k < min(kk + bs, K); ++k) {
Aik = A[i * K + k];
for (j = 0; j < ((N/8)*8); j+=8) {
C[i * N + j] += Aik * B[k * N + j];
C[i * N + j + 1] += Aik * B[k * N + j + 1];
C[i * N + j + 2] += Aik * B[k * N + j + 2];
C[i * N + j + 3] += Aik * B[k * N + j + 3];
C[i * N + j + 4] += Aik * B[k * N + j + 4];
C[i * N + j + 5] += Aik * B[k * N + j + 5];
C[i * N + j + 6] += Aik * B[k * N + j + 6];
C[i * N + j + 7] += Aik * B[k * N + j + 7];
}
for ( ; j < N; ++j)
C[i * N + j] += Aik * B[k * N + j];
}
}
}
return NULL;
}
void mat_mul(float *_A, float *_B, float *_C, int _M, int _N, int _K, int _num_threads) {
A = _A, B = _B, C = _C;
M = _M, N = _N, K = _K;
num_threads = _num_threads;
// TODO: create '_num_threads' pthreads
pthread_t * threads;
threads = (pthread_t *) malloc(sizeof(pthread_t) * num_threads);
for (int i = 0; i < num_threads; i++) {
int * pid = (int *) malloc(sizeof(int));
*pid = i;
pthread_create(&threads[i], NULL, mat_mul_thread, pid);
}
for (int i = 0; i < num_threads; i++) {
pthread_join(threads[i], NULL);
}
}