Reland "Integrate SIMD optimisations for zlib"

third_party/zlib/crc_folding.c

+/*
+ * Compute the CRC32 using a parallelized folding approach with the PCLMULQDQ
+ * instruction.
+ *
+ * A white paper describing this algorithm can be found at:
+ * http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf
+ *
+ * Copyright (C) 2013 Intel Corporation. All rights reserved.
+ * Authors:
+ *      Wajdi Feghali   <wajdi.k.feghali@intel.com>
+ *      Jim Guilford    <james.guilford@intel.com>
+ *      Vinodh Gopal    <vinodh.gopal@intel.com>
+ *      Erdinc Ozturk   <erdinc.ozturk@intel.com>
+ *      Jim Kukunas     <james.t.kukunas@linux.intel.com>
+ *
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include "deflate.h"
+
+#include <inttypes.h>
+#include <emmintrin.h>
+#include <immintrin.h>
+#include <wmmintrin.h>
+
+#define CRC_LOAD(s) \
+    do { \
+        __m128i xmm_crc0 = _mm_loadu_si128((__m128i *)s->crc0 + 0);\
+        __m128i xmm_crc1 = _mm_loadu_si128((__m128i *)s->crc0 + 1);\
+        __m128i xmm_crc2 = _mm_loadu_si128((__m128i *)s->crc0 + 2);\
+        __m128i xmm_crc3 = _mm_loadu_si128((__m128i *)s->crc0 + 3);\
+        __m128i xmm_crc_part = _mm_loadu_si128((__m128i *)s->crc0 + 4);
+
+#define CRC_SAVE(s) \
+        _mm_storeu_si128((__m128i *)s->crc0 + 0, xmm_crc0);\
+        _mm_storeu_si128((__m128i *)s->crc0 + 1, xmm_crc1);\
+        _mm_storeu_si128((__m128i *)s->crc0 + 2, xmm_crc2);\
+        _mm_storeu_si128((__m128i *)s->crc0 + 3, xmm_crc3);\
+        _mm_storeu_si128((__m128i *)s->crc0 + 4, xmm_crc_part);\
+    } while (0);
+
+ZLIB_INTERNAL void crc_fold_init(deflate_state *const s)
+{
+    CRC_LOAD(s)
+
+    xmm_crc0 = _mm_cvtsi32_si128(0x9db42487);
+    xmm_crc1 = _mm_setzero_si128();
+    xmm_crc2 = _mm_setzero_si128();
+    xmm_crc3 = _mm_setzero_si128();
+
+    CRC_SAVE(s)
+
+    s->strm->adler = 0;
+}
+
+local void fold_1(deflate_state *const s,
+        __m128i *xmm_crc0, __m128i *xmm_crc1,
+        __m128i *xmm_crc2, __m128i *xmm_crc3)
+{
+    const __m128i xmm_fold4 = _mm_set_epi32(
+            0x00000001, 0x54442bd4,
+            0x00000001, 0xc6e41596);
+
+    __m128i x_tmp3;
+    __m128 ps_crc0, ps_crc3, ps_res;
+
+    x_tmp3 = *xmm_crc3;
+
+    *xmm_crc3 = *xmm_crc0;
+    *xmm_crc0 = _mm_clmulepi64_si128(*xmm_crc0, xmm_fold4, 0x01);
+    *xmm_crc3 = _mm_clmulepi64_si128(*xmm_crc3, xmm_fold4, 0x10);
+    ps_crc0 = _mm_castsi128_ps(*xmm_crc0);
+    ps_crc3 = _mm_castsi128_ps(*xmm_crc3);
+    ps_res = _mm_xor_ps(ps_crc0, ps_crc3);
+
+    *xmm_crc0 = *xmm_crc1;
+    *xmm_crc1 = *xmm_crc2;
+    *xmm_crc2 = x_tmp3;
+    *xmm_crc3 = _mm_castps_si128(ps_res);
+}
+
+local void fold_2(deflate_state *const s,
+        __m128i *xmm_crc0, __m128i *xmm_crc1,
+        __m128i *xmm_crc2, __m128i *xmm_crc3)
+{
+    const __m128i xmm_fold4 = _mm_set_epi32(
+            0x00000001, 0x54442bd4,
+            0x00000001, 0xc6e41596);
+
+    __m128i x_tmp3, x_tmp2;
+    __m128 ps_crc0, ps_crc1, ps_crc2, ps_crc3, ps_res31, ps_res20;
+
+    x_tmp3 = *xmm_crc3;
+    x_tmp2 = *xmm_crc2;
+
+    *xmm_crc3 = *xmm_crc1;
+    *xmm_crc1 = _mm_clmulepi64_si128(*xmm_crc1, xmm_fold4, 0x01);
+    *xmm_crc3 = _mm_clmulepi64_si128(*xmm_crc3, xmm_fold4, 0x10);
+    ps_crc3 = _mm_castsi128_ps(*xmm_crc3);
+    ps_crc1 = _mm_castsi128_ps(*xmm_crc1);
+    ps_res31= _mm_xor_ps(ps_crc3, ps_crc1);
+
+    *xmm_crc2 = *xmm_crc0;
+    *xmm_crc0 = _mm_clmulepi64_si128(*xmm_crc0, xmm_fold4, 0x01);
+    *xmm_crc2 = _mm_clmulepi64_si128(*xmm_crc2, xmm_fold4, 0x10);
+    ps_crc0 = _mm_castsi128_ps(*xmm_crc0);
+    ps_crc2 = _mm_castsi128_ps(*xmm_crc2);
+    ps_res20= _mm_xor_ps(ps_crc0, ps_crc2);
+
+    *xmm_crc0 = x_tmp2;
+    *xmm_crc1 = x_tmp3;
+    *xmm_crc2 = _mm_castps_si128(ps_res20);
+    *xmm_crc3 = _mm_castps_si128(ps_res31);
+}
+
+local void fold_3(deflate_state *const s,
+        __m128i *xmm_crc0, __m128i *xmm_crc1,
+        __m128i *xmm_crc2, __m128i *xmm_crc3)
+{
+    const __m128i xmm_fold4 = _mm_set_epi32(
+            0x00000001, 0x54442bd4,
+            0x00000001, 0xc6e41596);
+
+    __m128i x_tmp3;
+    __m128 ps_crc0, ps_crc1, ps_crc2, ps_crc3, ps_res32, ps_res21, ps_res10;
+
+    x_tmp3 = *xmm_crc3;
+
+    *xmm_crc3 = *xmm_crc2;
+    *xmm_crc2 = _mm_clmulepi64_si128(*xmm_crc2, xmm_fold4, 0x01);
+    *xmm_crc3 = _mm_clmulepi64_si128(*xmm_crc3, xmm_fold4, 0x10);
+    ps_crc2 = _mm_castsi128_ps(*xmm_crc2);
+    ps_crc3 = _mm_castsi128_ps(*xmm_crc3);
+    ps_res32 = _mm_xor_ps(ps_crc2, ps_crc3);
+
+    *xmm_crc2 = *xmm_crc1;
+    *xmm_crc1 = _mm_clmulepi64_si128(*xmm_crc1, xmm_fold4, 0x01);
+    *xmm_crc2 = _mm_clmulepi64_si128(*xmm_crc2, xmm_fold4, 0x10);
+    ps_crc1 = _mm_castsi128_ps(*xmm_crc1);
+    ps_crc2 = _mm_castsi128_ps(*xmm_crc2);
+    ps_res21= _mm_xor_ps(ps_crc1, ps_crc2);
+
+    *xmm_crc1 = *xmm_crc0;
+    *xmm_crc0 = _mm_clmulepi64_si128(*xmm_crc0, xmm_fold4, 0x01);
+    *xmm_crc1 = _mm_clmulepi64_si128(*xmm_crc1, xmm_fold4, 0x10);
+    ps_crc0 = _mm_castsi128_ps(*xmm_crc0);
+    ps_crc1 = _mm_castsi128_ps(*xmm_crc1);
+    ps_res10= _mm_xor_ps(ps_crc0, ps_crc1);
+
+    *xmm_crc0 = x_tmp3;
+    *xmm_crc1 = _mm_castps_si128(ps_res10);
+    *xmm_crc2 = _mm_castps_si128(ps_res21);
+    *xmm_crc3 = _mm_castps_si128(ps_res32);
+}
+
+local void fold_4(deflate_state *const s,
+        __m128i *xmm_crc0, __m128i *xmm_crc1,
+        __m128i *xmm_crc2, __m128i *xmm_crc3)
+{
+    const __m128i xmm_fold4 = _mm_set_epi32(
+            0x00000001, 0x54442bd4,
+            0x00000001, 0xc6e41596);
+
+    __m128i x_tmp0, x_tmp1, x_tmp2, x_tmp3;
+    __m128 ps_crc0, ps_crc1, ps_crc2, ps_crc3;
+    __m128 ps_t0, ps_t1, ps_t2, ps_t3;
+    __m128 ps_res0, ps_res1, ps_res2, ps_res3;
+
+    x_tmp0 = *xmm_crc0;
+    x_tmp1 = *xmm_crc1;
+    x_tmp2 = *xmm_crc2;
+    x_tmp3 = *xmm_crc3;
+
+    *xmm_crc0 = _mm_clmulepi64_si128(*xmm_crc0, xmm_fold4, 0x01);
+    x_tmp0 = _mm_clmulepi64_si128(x_tmp0, xmm_fold4, 0x10);
+    ps_crc0 = _mm_castsi128_ps(*xmm_crc0);
+    ps_t0 = _mm_castsi128_ps(x_tmp0);
+    ps_res0 = _mm_xor_ps(ps_crc0, ps_t0);
+
+    *xmm_crc1 = _mm_clmulepi64_si128(*xmm_crc1, xmm_fold4, 0x01);
+    x_tmp1 = _mm_clmulepi64_si128(x_tmp1, xmm_fold4, 0x10);
+    ps_crc1 = _mm_castsi128_ps(*xmm_crc1);
+    ps_t1 = _mm_castsi128_ps(x_tmp1);
+    ps_res1 = _mm_xor_ps(ps_crc1, ps_t1);
+
+    *xmm_crc2 = _mm_clmulepi64_si128(*xmm_crc2, xmm_fold4, 0x01);
+    x_tmp2 = _mm_clmulepi64_si128(x_tmp2, xmm_fold4, 0x10);
+    ps_crc2 = _mm_castsi128_ps(*xmm_crc2);
+    ps_t2 = _mm_castsi128_ps(x_tmp2);
+    ps_res2 = _mm_xor_ps(ps_crc2, ps_t2);
+
+    *xmm_crc3 = _mm_clmulepi64_si128(*xmm_crc3, xmm_fold4, 0x01);
+    x_tmp3 = _mm_clmulepi64_si128(x_tmp3, xmm_fold4, 0x10);
+    ps_crc3 = _mm_castsi128_ps(*xmm_crc3);
+    ps_t3 = _mm_castsi128_ps(x_tmp3);
+    ps_res3 = _mm_xor_ps(ps_crc3, ps_t3);
+
+    *xmm_crc0 = _mm_castps_si128(ps_res0);
+    *xmm_crc1 = _mm_castps_si128(ps_res1);
+    *xmm_crc2 = _mm_castps_si128(ps_res2);
+    *xmm_crc3 = _mm_castps_si128(ps_res3);
+}
+
+local const unsigned zalign(32) pshufb_shf_table[60] = {
+        0x84838281,0x88878685,0x8c8b8a89,0x008f8e8d, /* shl 15 (16 - 1)/shr1 */
+        0x85848382,0x89888786,0x8d8c8b8a,0x01008f8e, /* shl 14 (16 - 3)/shr2 */
+        0x86858483,0x8a898887,0x8e8d8c8b,0x0201008f, /* shl 13 (16 - 4)/shr3 */
+        0x87868584,0x8b8a8988,0x8f8e8d8c,0x03020100, /* shl 12 (16 - 4)/shr4 */
+        0x88878685,0x8c8b8a89,0x008f8e8d,0x04030201, /* shl 11 (16 - 5)/shr5 */
+        0x89888786,0x8d8c8b8a,0x01008f8e,0x05040302, /* shl 10 (16 - 6)/shr6 */
+        0x8a898887,0x8e8d8c8b,0x0201008f,0x06050403, /* shl  9 (16 - 7)/shr7 */
+        0x8b8a8988,0x8f8e8d8c,0x03020100,0x07060504, /* shl  8 (16 - 8)/shr8 */
+        0x8c8b8a89,0x008f8e8d,0x04030201,0x08070605, /* shl  7 (16 - 9)/shr9 */
+        0x8d8c8b8a,0x01008f8e,0x05040302,0x09080706, /* shl  6 (16 -10)/shr10*/
+        0x8e8d8c8b,0x0201008f,0x06050403,0x0a090807, /* shl  5 (16 -11)/shr11*/
+        0x8f8e8d8c,0x03020100,0x07060504,0x0b0a0908, /* shl  4 (16 -12)/shr12*/
+        0x008f8e8d,0x04030201,0x08070605,0x0c0b0a09, /* shl  3 (16 -13)/shr13*/
+        0x01008f8e,0x05040302,0x09080706,0x0d0c0b0a, /* shl  2 (16 -14)/shr14*/
+        0x0201008f,0x06050403,0x0a090807,0x0e0d0c0b  /* shl  1 (16 -15)/shr15*/
+};
+
+local void partial_fold(deflate_state *const s, const size_t len,
+        __m128i *xmm_crc0, __m128i *xmm_crc1,
+        __m128i *xmm_crc2, __m128i *xmm_crc3,
+        __m128i *xmm_crc_part)
+{
+
+    const __m128i xmm_fold4 = _mm_set_epi32(
+            0x00000001, 0x54442bd4,
+            0x00000001, 0xc6e41596);
+    const __m128i xmm_mask3 = _mm_set1_epi32(0x80808080);
+
+    __m128i xmm_shl, xmm_shr, xmm_tmp1, xmm_tmp2, xmm_tmp3;
+    __m128i xmm_a0_0, xmm_a0_1;
+    __m128 ps_crc3, psa0_0, psa0_1, ps_res;
+
+    xmm_shl = _mm_load_si128((__m128i *)pshufb_shf_table + (len - 1));
+    xmm_shr = xmm_shl;
+    xmm_shr = _mm_xor_si128(xmm_shr, xmm_mask3);
+
+    xmm_a0_0 = _mm_shuffle_epi8(*xmm_crc0, xmm_shl);
+
+    *xmm_crc0 = _mm_shuffle_epi8(*xmm_crc0, xmm_shr);
+    xmm_tmp1 = _mm_shuffle_epi8(*xmm_crc1, xmm_shl);
+    *xmm_crc0 = _mm_or_si128(*xmm_crc0, xmm_tmp1);
+
+    *xmm_crc1 = _mm_shuffle_epi8(*xmm_crc1, xmm_shr);
+    xmm_tmp2 = _mm_shuffle_epi8(*xmm_crc2, xmm_shl);
+    *xmm_crc1 = _mm_or_si128(*xmm_crc1, xmm_tmp2);
+
+    *xmm_crc2 = _mm_shuffle_epi8(*xmm_crc2, xmm_shr);
+    xmm_tmp3 = _mm_shuffle_epi8(*xmm_crc3, xmm_shl);
+    *xmm_crc2 = _mm_or_si128(*xmm_crc2, xmm_tmp3);
+
+    *xmm_crc3 = _mm_shuffle_epi8(*xmm_crc3, xmm_shr);
+    *xmm_crc_part = _mm_shuffle_epi8(*xmm_crc_part, xmm_shl);
+    *xmm_crc3 = _mm_or_si128(*xmm_crc3, *xmm_crc_part);
+
+    xmm_a0_1 = _mm_clmulepi64_si128(xmm_a0_0, xmm_fold4, 0x10);
+    xmm_a0_0 = _mm_clmulepi64_si128(xmm_a0_0, xmm_fold4, 0x01);
+
+    ps_crc3 = _mm_castsi128_ps(*xmm_crc3);
+    psa0_0 = _mm_castsi128_ps(xmm_a0_0);
+    psa0_1 = _mm_castsi128_ps(xmm_a0_1);
+
+    ps_res = _mm_xor_ps(ps_crc3, psa0_0);
+    ps_res = _mm_xor_ps(ps_res, psa0_1);
+
+    *xmm_crc3 = _mm_castps_si128(ps_res);
+}
+
+ZLIB_INTERNAL void crc_fold_copy(deflate_state *const s,
+        unsigned char *dst, const unsigned char *src, long len)
+{
+    unsigned long algn_diff;
+    __m128i xmm_t0, xmm_t1, xmm_t2, xmm_t3;
+
+    CRC_LOAD(s)
+
+    if (len < 16) {
+        if (len == 0)
+            return;
+        goto partial;
+    }
+
+    algn_diff = 0 - (unsigned long)src & 0xF;
+    if (algn_diff) {
+        xmm_crc_part = _mm_loadu_si128((__m128i *)src);
+        _mm_storeu_si128((__m128i *)dst, xmm_crc_part);
+
+        dst += algn_diff;
+        src += algn_diff;
+        len -= algn_diff;
+
+        partial_fold(s, algn_diff, &xmm_crc0, &xmm_crc1, &xmm_crc2, &xmm_crc3,
+            &xmm_crc_part);
+    }
+
+    while ((len -= 64) >= 0) {
+        xmm_t0 = _mm_load_si128((__m128i *)src);
+        xmm_t1 = _mm_load_si128((__m128i *)src + 1);
+        xmm_t2 = _mm_load_si128((__m128i *)src + 2);
+        xmm_t3 = _mm_load_si128((__m128i *)src + 3);
+
+        fold_4(s, &xmm_crc0, &xmm_crc1, &xmm_crc2, &xmm_crc3);
+
+        _mm_storeu_si128((__m128i *)dst, xmm_t0);
+        _mm_storeu_si128((__m128i *)dst + 1, xmm_t1);
+        _mm_storeu_si128((__m128i *)dst + 2, xmm_t2);
+        _mm_storeu_si128((__m128i *)dst + 3, xmm_t3);
+
+        xmm_crc0 = _mm_xor_si128(xmm_crc0, xmm_t0);
+        xmm_crc1 = _mm_xor_si128(xmm_crc1, xmm_t1);
+        xmm_crc2 = _mm_xor_si128(xmm_crc2, xmm_t2);
+        xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_t3);
+
+        src += 64;
+        dst += 64;
+    }
+
+    /*
+     * len = num bytes left - 64
+     */
+    if (len + 16 >= 0) {
+        len += 16;
+
+        xmm_t0 = _mm_load_si128((__m128i *)src);
+        xmm_t1 = _mm_load_si128((__m128i *)src + 1);
+        xmm_t2 = _mm_load_si128((__m128i *)src + 2);
+
+        fold_3(s, &xmm_crc0, &xmm_crc1, &xmm_crc2, &xmm_crc3);
+
+        _mm_storeu_si128((__m128i *)dst, xmm_t0);
+        _mm_storeu_si128((__m128i *)dst + 1, xmm_t1);
+        _mm_storeu_si128((__m128i *)dst + 2, xmm_t2);
+
+        xmm_crc1 = _mm_xor_si128(xmm_crc1, xmm_t0);
+        xmm_crc2 = _mm_xor_si128(xmm_crc2, xmm_t1);
+        xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_t2);
+
+        if (len == 0)
+            goto done;
+
+        dst += 48;
+        src += 48;
+    } else if (len + 32 >= 0) {
+        len += 32;
+
+        xmm_t0 = _mm_load_si128((__m128i *)src);
+        xmm_t1 = _mm_load_si128((__m128i *)src + 1);
+
+        fold_2(s, &xmm_crc0, &xmm_crc1, &xmm_crc2, &xmm_crc3);
+
+        _mm_storeu_si128((__m128i *)dst, xmm_t0);
+        _mm_storeu_si128((__m128i *)dst + 1, xmm_t1);
+
+        xmm_crc2 = _mm_xor_si128(xmm_crc2, xmm_t0);
+        xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_t1);
+
+        if (len == 0)
+            goto done;
+
+        dst += 32;
+        src += 32;
+    } else if (len + 48 >= 0) {
+        len += 48;
+
+        xmm_t0 = _mm_load_si128((__m128i *)src);
+
+        fold_1(s, &xmm_crc0, &xmm_crc1, &xmm_crc2, &xmm_crc3);
+
+        _mm_storeu_si128((__m128i *)dst, xmm_t0);
+
+        xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_t0);
+
+        if (len == 0)
+            goto done;
+
+        dst += 16;
+        src += 16;
+    } else {
+        len += 64;
+        if (len == 0)
+            goto done;
+    }
+
+partial:
+
+#if defined(_MSC_VER)
+    /* VS does not permit the use of _mm_set_epi64x in 32-bit builds */
+    {
+        int32_t parts[4] = {0, 0, 0, 0};
+        memcpy(&parts, src, len);
+        xmm_crc_part = _mm_set_epi32(parts[3], parts[2], parts[1], parts[0]);
+    }
+#else
+    {
+        int64_t parts[2] = {0, 0};
+        memcpy(&parts, src, len);
+        xmm_crc_part = _mm_set_epi64x(parts[1], parts[0]);
+    }
+#endif
+
+    _mm_storeu_si128((__m128i *)dst, xmm_crc_part);
+    partial_fold(s, len, &xmm_crc0, &xmm_crc1, &xmm_crc2, &xmm_crc3,
+        &xmm_crc_part);
+done:
+    CRC_SAVE(s)
+}
+
+local const unsigned zalign(16) crc_k[] = {
+    0xccaa009e, 0x00000000, /* rk1 */
+    0x751997d0, 0x00000001, /* rk2 */
+    0xccaa009e, 0x00000000, /* rk5 */
+    0x63cd6124, 0x00000001, /* rk6 */
+    0xf7011640, 0x00000001, /* rk7 */
+    0xdb710640, 0x00000001  /* rk8 */
+};
+
+local const unsigned zalign(16) crc_mask[4] = {
+    0xFFFFFFFF, 0xFFFFFFFF, 0x00000000, 0x00000000
+};
+
+local const unsigned zalign(16) crc_mask2[4] = {
+    0x00000000, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF
+};
+
+unsigned ZLIB_INTERNAL crc_fold_512to32(deflate_state *const s)
+{
+    const __m128i xmm_mask  = _mm_load_si128((__m128i *)crc_mask);
+    const __m128i xmm_mask2 = _mm_load_si128((__m128i *)crc_mask2);
+
+    unsigned crc;
+    __m128i x_tmp0, x_tmp1, x_tmp2, crc_fold;
+
+    CRC_LOAD(s)
+
+    /*
+     * k1
+     */
+    crc_fold = _mm_load_si128((__m128i *)crc_k);
+
+    x_tmp0 = _mm_clmulepi64_si128(xmm_crc0, crc_fold, 0x10);
+    xmm_crc0 = _mm_clmulepi64_si128(xmm_crc0, crc_fold, 0x01);
+    xmm_crc1 = _mm_xor_si128(xmm_crc1, x_tmp0);
+    xmm_crc1 = _mm_xor_si128(xmm_crc1, xmm_crc0);
+
+    x_tmp1 = _mm_clmulepi64_si128(xmm_crc1, crc_fold, 0x10);
+    xmm_crc1 = _mm_clmulepi64_si128(xmm_crc1, crc_fold, 0x01);
+    xmm_crc2 = _mm_xor_si128(xmm_crc2, x_tmp1);
+    xmm_crc2 = _mm_xor_si128(xmm_crc2, xmm_crc1);
+
+    x_tmp2 = _mm_clmulepi64_si128(xmm_crc2, crc_fold, 0x10);
+    xmm_crc2 = _mm_clmulepi64_si128(xmm_crc2, crc_fold, 0x01);
+    xmm_crc3 = _mm_xor_si128(xmm_crc3, x_tmp2);
+    xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_crc2);
+
+    /*
+     * k5
+     */
+    crc_fold = _mm_load_si128((__m128i *)crc_k + 1);
+
+    xmm_crc0 = xmm_crc3;
+    xmm_crc3 = _mm_clmulepi64_si128(xmm_crc3, crc_fold, 0);
+    xmm_crc0 = _mm_srli_si128(xmm_crc0, 8);
+    xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_crc0);
+
+    xmm_crc0 = xmm_crc3;
+    xmm_crc3 = _mm_slli_si128(xmm_crc3, 4);
+    xmm_crc3 = _mm_clmulepi64_si128(xmm_crc3, crc_fold, 0x10);
+    xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_crc0);
+    xmm_crc3 = _mm_and_si128(xmm_crc3, xmm_mask2);
+
+    /*
+     * k7
+     */
+    xmm_crc1 = xmm_crc3;
+    xmm_crc2 = xmm_crc3;
+    crc_fold = _mm_load_si128((__m128i *)crc_k + 2);
+
+    xmm_crc3 = _mm_clmulepi64_si128(xmm_crc3, crc_fold, 0);
+    xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_crc2);
+    xmm_crc3 = _mm_and_si128(xmm_crc3, xmm_mask);
+
+    xmm_crc2 = xmm_crc3;
+    xmm_crc3 = _mm_clmulepi64_si128(xmm_crc3, crc_fold, 0x10);
+    xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_crc2);
+    xmm_crc3 = _mm_xor_si128(xmm_crc3, xmm_crc1);
+
+    crc = _mm_extract_epi32(xmm_crc3, 2);
+    return ~crc;
+    CRC_SAVE(s)
+}