zstd/compress/zstd_lazy.c

766 typedef U64 ZSTD_VecMask;   /* Clarifies when we are interacting with a U64 representing a mask of matches */
933  * Skips sections of long matches as is necessary.
982     int matches[4] = {0};
988         matches[i] = _mm_movemask_epi8(equalMask);
990     if (nbChunks == 1) return ZSTD_rotateRight_U16((U16)matches[0], head);
991     if (nbChunks == 2) return ZSTD_rotateRight_U32((U32)matches[1] << 16 | (U32)matches[0], head);
993     return ZSTD_rotateRight_U64((U64)matches[3] << 48 | (U64)matches[2] << 32 | (U64)matches[1] << 16 | (U64)matches[0], head);
997 /* Returns a ZSTD_VecMask (U32) that has the nth bit set to 1 if the newly-computed "tag" matches
999  * Each row is a circular buffer beginning at the value of "head". So we must rotate the "matches" bitfield
1040             const U32 matches = vget_lane_u32(vreinterpret_u32_u8(t4), 0);
1041             return ZSTD_rotateRight_U32(matches, head);
1055             const U64 matches = vget_lane_u64(vreinterpret_u64_u8(t4), 0);
1056             return ZSTD_rotateRight_U64(matches, head);
1067         ZSTD_VecMask matches = 0;
1076                 matches <<= chunkSize;
1077                 matches |= (chunk * extractMagic) >> shiftAmount;
1087                 matches <<= chunkSize;
1088                 matches |= ((chunk >> 7) * extractMagic) >> shiftAmount;
1092         matches = ~matches;
1094             return ZSTD_rotateRight_U16((U16)matches, head);
1096             return ZSTD_rotateRight_U32((U32)matches, head);
1098             return ZSTD_rotateRight_U64((U64)matches, head);
1192         ZSTD_VecMask matches = ZSTD_row_getMatchMask(tagRow, (BYTE)tag, head, rowEntries);
1194         /* Cycle through the matches and prefetch */
1195         for (; (matches > 0) && (nbAttempts > 0); --nbAttempts, matches &= (matches - 1)) {
1196             U32 const matchPos = (head + ZSTD_VecMask_next(matches)) & rowMask;
1261             ZSTD_VecMask matches = ZSTD_row_getMatchMask(dmsTagRow, (BYTE)dmsTag, head, rowEntries);
1263             for (; (matches > 0) && (nbAttempts > 0); --nbAttempts, matches &= (matches - 1)) {
1264                 U32 const matchPos = (head + ZSTD_VecMask_next(matches)) & rowMask;