check_cxx_source_compiles("
#include <tmmintrin.h>

int main() {
  const __m128i *src = 0;
  __m128i dest;
  const __m128i shuffle_mask = _mm_load_si128(src);
  const __m128i pattern = _mm_shuffle_epi8(_mm_loadl_epi64(src), shuffle_mask);
  _mm_storeu_si128(&dest, pattern);
  return 0;
}" SNAPPY_HAVE_SSSE3)