From da435823941df5f55956a60ea6e0672c9a5093ca Mon Sep 17 00:00:00 2001 From: Dmitrii Krosh Date: Mon, 3 Aug 2026 12:26:01 +0300 Subject: [PATCH] fused decoder for hash_set --- new_version/direct_hash/about.md | 14 +++ new_version/direct_hash/hash_set.c | 158 ++++++++++++++--------------- 2 files changed, 90 insertions(+), 82 deletions(-) diff --git a/new_version/direct_hash/about.md b/new_version/direct_hash/about.md index 5b46394..1b5f21d 100644 --- a/new_version/direct_hash/about.md +++ b/new_version/direct_hash/about.md @@ -5,3 +5,17 @@ - позволить индексироваться по элементам хэша - кратно сократить время на дешифровку - кэшировать можно соответствия индекс - значение, чтобы не работать с битами (может и не стоит того) + - стоит этого + +```text +symbols=1000 required=500 bpp=32 +implementation set_chars format +set9 3994 golomb/base62 +direct 5340 D1/base64 + +operation set9 direct direct/set9 +set_fini only 150.44 us 99.28 us 0.66x +new+add+fini 1034.22 us 949.62 us 0.92x +rpmsetcmp cold 292.86 us 210.30 us 0.72x +rpmsetcmp warm 5.89 us 23.02 us 3.91x +``` diff --git a/new_version/direct_hash/hash_set.c b/new_version/direct_hash/hash_set.c index 019275b..65fc4d7 100644 --- a/new_version/direct_hash/hash_set.c +++ b/new_version/direct_hash/hash_set.c @@ -245,56 +245,45 @@ const char* set_fini(struct set* set, int bpp) { return output; } -static int base64_value(unsigned char c) { - if (c >= 'A' && c <= 'Z') return c - 'A'; - if (c >= 'a' && c <= 'z') return c - 'a' + 26; - if (c >= '0' && c <= '9') return c - '0' + 52; - if (c == '+') return 62; - if (c == '/') return 63; - return -1; -} +static const unsigned char base64_values[256] = { + ['A'] = 1, ['B'] = 2, ['C'] = 3, ['D'] = 4, ['E'] = 5, ['F'] = 6, ['G'] = 7, ['H'] = 8, + ['I'] = 9, ['J'] = 10, ['K'] = 11, ['L'] = 12, ['M'] = 13, ['N'] = 14, ['O'] = 15, ['P'] = 16, + ['Q'] = 17, ['R'] = 18, ['S'] = 19, ['T'] = 20, ['U'] = 21, ['V'] = 22, ['W'] = 23, ['X'] = 24, + ['Y'] = 25, ['Z'] = 26, ['a'] = 27, ['b'] = 28, ['c'] = 29, ['d'] = 30, ['e'] = 31, ['f'] = 32, + ['g'] = 33, ['h'] = 34, ['i'] = 35, ['j'] = 36, ['k'] = 37, ['l'] = 38, ['m'] = 39, ['n'] = 40, + ['o'] = 41, ['p'] = 42, ['q'] = 43, ['r'] = 44, ['s'] = 45, ['t'] = 46, ['u'] = 47, ['v'] = 48, + ['w'] = 49, ['x'] = 50, ['y'] = 51, ['z'] = 52, ['0'] = 53, ['1'] = 54, ['2'] = 55, ['3'] = 56, + ['4'] = 57, ['5'] = 58, ['6'] = 59, ['7'] = 60, ['8'] = 61, ['9'] = 62, ['+'] = 63, ['/'] = 64, +}; -static int base64_decode(const char* input, size_t input_len, unsigned char** bytes, - size_t* byte_count) { - if (input_len == 0 || input_len % 4 != 0) return -1; - if (input_len / 4 > SIZE_MAX / 3) return -1; +static inline int base64_value(unsigned char c) { return (int)base64_values[c] - 1; } - size_t capacity = input_len / 4 * 3; - unsigned char* output = xmalloc(capacity); - unsigned char* destination = output; +struct decode_writer { + unsigned* hashes; + size_t capacity; + size_t written; + uint64_t bits; + uint64_t mask; + unsigned filled; + unsigned bpp; +}; - for (size_t offset = 0; offset < input_len; offset += 4) { - int v0 = base64_value((unsigned char)input[offset]); - int v1 = base64_value((unsigned char)input[offset + 1]); - int last = offset + 4 == input_len; - if (v0 < 0 || v1 < 0) goto invalid; +static inline int decode_writer_put(struct decode_writer* writer, uint32_t bytes, + unsigned byte_count) { + writer->bits |= (uint64_t)bytes << writer->filled; + writer->filled += byte_count * 8; - *destination++ = (unsigned char)((v0 << 2) | (v1 >> 4)); - if (input[offset + 2] == '=') { - if (!last || input[offset + 3] != '=' || (v1 & 0x0f) != 0) goto invalid; - continue; - } + while (writer->filled >= writer->bpp) { + if (writer->written == writer->capacity) return -1; - int v2 = base64_value((unsigned char)input[offset + 2]); - if (v2 < 0) goto invalid; - *destination++ = (unsigned char)((v1 << 4) | (v2 >> 2)); - if (input[offset + 3] == '=') { - if (!last || (v2 & 0x03) != 0) goto invalid; - continue; - } - - int v3 = base64_value((unsigned char)input[offset + 3]); - if (v3 < 0) goto invalid; - *destination++ = (unsigned char)((v2 << 6) | v3); + unsigned current = (unsigned)(writer->bits & writer->mask); + writer->bits >>= writer->bpp; + writer->filled -= writer->bpp; + if (writer->written > 0 && writer->hashes[writer->written - 1] >= current) return -1; + writer->hashes[writer->written++] = current; } - *bytes = output; - *byte_count = (size_t)(destination - output); return 0; - -invalid: - _free(output); - return -1; } static int decode_set(const char* str, struct decoded_set* decoded) { @@ -307,62 +296,67 @@ static int decode_set(const char* str, struct decoded_set* decoded) { unsigned bpp = (unsigned)(str[2] - '0') * 10 + (unsigned)(str[3] - '0'); if (bpp < 10 || bpp > 32) return -1; - unsigned char* bytes; - size_t byte_count; - if (base64_decode(str + FORMAT_HEADER_LEN, str_len - FORMAT_HEADER_LEN, &bytes, &byte_count) < 0) - return -1; - if (byte_count > SIZE_MAX / 8) { - _free(bytes); - return -1; - } + const char* input = str + FORMAT_HEADER_LEN; + size_t input_len = str_len - FORMAT_HEADER_LEN; + if (input_len == 0 || input_len % 4 != 0 || input_len / 4 > SIZE_MAX / 3) return -1; + + size_t byte_count = input_len / 4 * 3; + if (input[input_len - 1] == '=') --byte_count; + if (input[input_len - 2] == '=') --byte_count; + if (byte_count > SIZE_MAX / 8) return -1; size_t count = byte_count * 8 / bpp; - if (count == 0 || count > (SIZE_MAX - 7) / bpp || (count * bpp + 7) / 8 != byte_count) { - _free(bytes); + if (count == 0 || count > (SIZE_MAX - 7) / bpp || count > SIZE_MAX / sizeof(unsigned) || + (count * bpp + 7) / 8 != byte_count) { return -1; } unsigned* hashes = xmalloc(count * sizeof(*hashes)); - const unsigned char* input = bytes; - const unsigned char* input_end = bytes + byte_count; - uint64_t bits = 0; - unsigned filled = 0; - uint64_t mask = bpp < 32 ? (UINT64_C(1) << bpp) - 1 : UINT32_MAX; + struct decode_writer writer = { + .hashes = hashes, + .capacity = count, + .mask = bpp < 32 ? (UINT64_C(1) << bpp) - 1 : UINT32_MAX, + .bpp = bpp, + }; - for (size_t i = 0; i < count; ++i) { - while (filled < bpp) { - if (input == input_end) { - _free(hashes); - _free(bytes); - return -1; - } - bits |= (uint64_t)*input++ << filled; - filled += 8; + for (size_t offset = 0; offset < input_len; offset += 4) { + int v0 = base64_value((unsigned char)input[offset]); + int v1 = base64_value((unsigned char)input[offset + 1]); + int last = offset + 4 == input_len; + if (v0 < 0 || v1 < 0) goto invalid; + + uint32_t bytes = (uint32_t)((v0 << 2) | (v1 >> 4)); + if (input[offset + 2] == '=') { + if (!last || input[offset + 3] != '=' || (v1 & 0x0f) != 0 || + decode_writer_put(&writer, bytes, 1) < 0) + goto invalid; + continue; } - hashes[i] = (unsigned)(bits & mask); - bits >>= bpp; - filled -= bpp; - if (i > 0 && hashes[i - 1] >= hashes[i]) { - _free(hashes); - _free(bytes); - return -1; + + int v2 = base64_value((unsigned char)input[offset + 2]); + if (v2 < 0) goto invalid; + bytes |= (uint32_t)(((v1 & 0x0f) << 4) | (v2 >> 2)) << 8; + if (input[offset + 3] == '=') { + if (!last || (v2 & 0x03) != 0 || decode_writer_put(&writer, bytes, 2) < 0) goto invalid; + continue; } + + int v3 = base64_value((unsigned char)input[offset + 3]); + if (v3 < 0) goto invalid; + bytes |= (uint32_t)(((v2 & 0x03) << 6) | v3) << 16; + if (decode_writer_put(&writer, bytes, 3) < 0) goto invalid; } - while (input < input_end) { - bits |= (uint64_t)*input++ << filled; - filled += 8; - } - _free(bytes); - if (bits != 0) { - _free(hashes); - return -1; - } + if (writer.written != count || writer.bits != 0) goto invalid; decoded->hashes = hashes; decoded->count = count; decoded->bpp = bpp; return 0; + +invalid: + _free(hashes); + return -1; } /* Reduce a sorted set of (bpp + 1)-bit values to a sorted set of bpp-bit values. */