Function test_advanced_integer

tests/fuzz.cpp:1446–1486

Strategy 23: Advanced Integer Operations * * Tests SSSE3/SSE4.1 advanced integer intrinsics: * - _mm_minpos_epu16: horizontal minimum with position * - _mm_mulhrs_epi16: high-rounding multiply * - _mm_packus_epi32: 32-to-16 unsigned packing * - 64-bit insert/extract */

 * - 64-bit insert/extract
 */
static void test_advanced_integer(const uint8_t *data, size_t size)
{
    if (size < 32)
        return;

    __m128i a = _mm_loadu_si128((const __m128i *) data);
    __m128i b = _mm_loadu_si128((const __m128i *) (data + 16));

    /* Horizontal minimum with position (SSE4.1) */
    SINK_I128(_mm_minpos_epu16(a));

    /* High-rounding multiply (SSSE3) */
    SINK_I128(_mm_mulhrs_epi16(a, b));

    /* 32-to-16 unsigned pack (SSE4.1) */
    SINK_I128(_mm_packus_epi32(a, b));

    /* 64-bit extract/insert (SSE4.1, 64-bit only) */
#if defined(__x86_64__) || defined(__aarch64__) || defined(_M_ARM64)
    SINK_I64(_mm_extract_epi64(a, 0));
    SINK_I64(_mm_extract_epi64(a, 1));

    int64_t insert_val =
        get_u32(data, size, 0) | ((int64_t) get_u32(data, size, 4) << 32);
    SINK_I128(_mm_insert_epi64(a, insert_val, 0));
    SINK_I128(_mm_insert_epi64(a, insert_val, 1));
#endif

    /* Edge cases for minpos */
    __m128i all_max = _mm_set1_epi16((short) 0xFFFF);
    __m128i all_zero = _mm_setzero_si128();
    SINK_I128(_mm_minpos_epu16(all_max));
    SINK_I128(_mm_minpos_epu16(all_zero));

    /* mulhrs edge cases */
    __m128i max16 = _mm_set1_epi16((short) 0x7FFF);
    __m128i min16 = _mm_set1_epi16((short) 0x8000);
    SINK_I128(_mm_mulhrs_epi16(max16, max16));
    SINK_I128(_mm_mulhrs_epi16(min16, min16));
    SINK_I128(_mm_mulhrs_epi16(max16, min16));
}

/* Strategy 24: Scalar Upper Lane Preservation
 *