C code :
static void FUNC(put_hevc_qpel_pixels)(int16_t *dst, ptrdiff_t dststride,
                                       uint8_t *_src, ptrdiff_t _srcstride,
                                       int width, int height, int16_t* mcbuffer)
{
    int x, y;
    pixel *src          = (pixel *)_src;
    ptrdiff_t srcstride = _srcstride / sizeof(pixel);

    for (y = 0; y < height; y++) {
        for (x = 0; x < width; x++)
            dst[x] = src[x] << (14 - BIT_DEPTH);
        src += srcstride;
        dst += dststride;
    }
}

intrinsics :

void ff_hevc_put_hevc_qpel_pixels_8_sse(int16_t *dst, ptrdiff_t dststride,
        uint8_t *_src, ptrdiff_t _srcstride, int width, int height,
        int16_t* mcbuffer) {
    int x, y;
    __m128i x1, x2, x3, x0, x4;
    uint8_t *src = (uint8_t*) _src;
    ptrdiff_t srcstride = _srcstride;
    x0= _mm_setzero_si128();
    if(!(width & 15)){
        for (y = 0; y < height; y++) {
            for (x = 0; x < width; x += 16) {

                x1 = _mm_loadu_si128((__m128i *) &src[x]);
                x2 = _mm_unpacklo_epi8(x1, x0);

                x3 = _mm_unpackhi_epi8(x1, x0);

                x2 = _mm_slli_epi16(x2, 6);
                x3 = _mm_slli_epi16(x3, 6);
                _mm_storeu_si128((__m128i *) &dst[x], x2);
                _mm_storeu_si128((__m128i *) &dst[x + 8], x3);

            }
            src += srcstride;
            dst += dststride;
        }
    }else if(!(width & 7)){
        for (y = 0; y < height; y++) {
            for (x = 0; x < width; x += 8) {

                x1 = _mm_loadl_epi64((__m128i *) &src[x]);
                x2 = _mm_unpacklo_epi8(x1, x0);
                x2 = _mm_slli_epi16(x2, 6);
                _mm_storeu_si128((__m128i *) &dst[x], x2);

            }
            src += srcstride;
            dst += dststride;
        }
    }else if(!(width & 3)){
        for (y = 0; y < height; y++) {
            for(x=0;x<width;x+=4){
                x1 = _mm_loadu_si128((__m128i *) &src[x]);
                x2 = _mm_unpacklo_epi8(x1, x0);
                x2 = _mm_slli_epi16(x2, 6);
                _mm_storel_epi64((__m128i *) &dst[x], x2);
            }
            src += srcstride;
            dst += dststride;
        }
    }else{
        x4= _mm_set_epi32(0,0,0,-1); //mask to store
        for (y = 0; y < height; y++) {
            for(x=0;x<width;x+=2){
                x1 = _mm_loadl_epi64((__m128i *) &src[x]);
                x2 = _mm_unpacklo_epi8(x1, x0);
                x2 = _mm_slli_epi16(x2, 6);
                _mm_maskmoveu_si128(x2,x4,(char *) (dst+x));
            }
            src += srcstride;
            dst += dststride;
        }
    }


}