...

#define INLINE __inline__
#define RESTRICT __restrict__
#define FORCEINLINE __attribute__((always_inline))
#define ALIGN(x) __attribute__((aligned(x)))

typedef struct {
  float x,y,z,w;
} ALIGN(16) vector4_t;

...

#define RIGIDBODY_SIZE 64

typedef struct {
  size_t size;
  vector4_t position[RIGIDBODY_SIZE];
  vector4_t velocity[RIGIDBODY_SIZE];
} rigidbody_t;

...

void physics_integrate(rigidbody_t *RESTRICT rigidbody) {

  // Load
  size_t index = rigidbody->size;
  vector4_t *RESTRICT positions = rigidbody->position;
  vector4_t *RESTRICT velocities = rigidbody->velocity;

  // Transform
  while(index--) {

    // Load
    vector4_t position = positions[index];
    vector4_t velocity = velocities[index];

    // Transform
    vector4_t result = vector4_add(position, velocity);

    // Store
    positions[index] = result;

  }

  // Store

}

...