How do you load/store from/to an array of doubles with GNU C Vector Extensions?

Question

I\'m using GNU C Vector Extensions, not Intel\'s _mm_* intrinsics.

I want to do the same thing as Intel\'s _m256_loadu_pd intrinsic. Assign

Answer 1

If you don't need to get a copy of a, use a pointer instead (see v_ptr in example). If you need a copy, use memmove (see v_copy)

#include 
#include 

typedef double vector __attribute__((vector_size(4 * sizeof(double))));

int main(int argc, char **argv) {
  double a[4] = {1.0, 2.0, 3.0, 4.0};
  vector *v_ptr;
  vector v_copy;

  v_ptr = (vector*)&a;
  memmove(&v_copy, a, sizeof(a));

  printf("a[0] = %f // v[0] = %f // v_copy[0] = %f\n", a[0], (*v_ptr)[0], v_copy[0]);
  printf("a[2] = %f // v[2] = %f // v_copy[0] = %f\n", a[2], (*v_ptr)[2], v_copy[2]);
  return 0;
}

output:

a[0] = 1.000000 // v[0] = 1.000000 // v_copy[0] = 1.000000
a[2] = 3.000000 // v[2] = 3.000000 // v_copy[0] = 3.000000