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744 lines
20 KiB
C++
744 lines
20 KiB
C++
#pragma once
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#include <DB/Common/UTF8Helpers.h>
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#include <ext/range.hpp>
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#include <Poco/UTF8Encoding.h>
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#include <Poco/Unicode.h>
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#include <stdint.h>
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#include <string.h>
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#if defined(__x86_64__)
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#include <smmintrin.h>
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#endif
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namespace DB
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{
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namespace ErrorCodes
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{
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extern const int UNSUPPORTED_PARAMETER;
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}
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/** Варианты поиска подстроки в строке.
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* В большинстве случаев, менее производительные, чем Volnitsky (см. Volnitsky.h).
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*/
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struct StringSearcherBase
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{
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#if defined(__x86_64__)
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static constexpr auto n = sizeof(__m128i);
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const int page_size = getpagesize();
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bool page_safe(const void * const ptr) const
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{
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return ((page_size - 1) & reinterpret_cast<std::uintptr_t>(ptr)) <= page_size - n;
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}
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#endif
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};
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/// Performs case-sensitive and case-insensitive search of UTF-8 strings
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template <bool CaseSensitive, bool ASCII> class StringSearcher;
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/// Case-insensitive UTF-8 searcher
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template <>
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class StringSearcher<false, false> : private StringSearcherBase
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{
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private:
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using UTF8SequenceBuffer = UInt8[6];
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/// string to be searched for
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const UInt8 * const needle;
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const std::size_t needle_size;
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const UInt8 * const needle_end = needle + needle_size;
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/// lower and uppercase variants of the first octet of the first character in `needle`
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bool first_needle_symbol_is_ascii{};
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UInt8 l{};
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UInt8 u{};
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#if defined(__x86_64__)
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/// vectors filled with `l` and `u`, for determining leftmost position of the first symbol
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__m128i patl, patu;
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/// lower and uppercase vectors of first 16 characters of `needle`
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__m128i cachel = _mm_setzero_si128(), cacheu = _mm_setzero_si128();
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int cachemask{};
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std::size_t cache_valid_len{};
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std::size_t cache_actual_len{};
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#endif
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public:
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StringSearcher(const char * const needle_, const std::size_t needle_size)
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: needle{reinterpret_cast<const UInt8 *>(needle_)}, needle_size{needle_size}
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{
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if (0 == needle_size)
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return;
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static const Poco::UTF8Encoding utf8;
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UTF8SequenceBuffer l_seq, u_seq;
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if (*needle < 0x80u)
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{
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first_needle_symbol_is_ascii = true;
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l = static_cast<const UInt8>(std::tolower(*needle));
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u = static_cast<const UInt8>(std::toupper(*needle));
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}
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else
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{
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const auto first_u32 = utf8.convert(needle);
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const auto first_l_u32 = Poco::Unicode::toLower(first_u32);
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const auto first_u_u32 = Poco::Unicode::toUpper(first_u32);
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/// lower and uppercase variants of the first octet of the first character in `needle`
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utf8.convert(first_l_u32, l_seq, sizeof(l_seq));
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l = l_seq[0];
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utf8.convert(first_u_u32, u_seq, sizeof(u_seq));
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u = u_seq[0];
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}
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#if defined(__x86_64__)
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/// for detecting leftmost position of the first symbol
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patl = _mm_set1_epi8(l);
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patu = _mm_set1_epi8(u);
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/// lower and uppercase vectors of first 16 octets of `needle`
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auto needle_pos = needle;
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for (std::size_t i = 0; i < n;)
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{
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if (needle_pos == needle_end)
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{
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cachel = _mm_srli_si128(cachel, 1);
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cacheu = _mm_srli_si128(cacheu, 1);
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++i;
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continue;
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}
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const auto src_len = DB::UTF8::seqLength(*needle_pos);
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const auto c_u32 = utf8.convert(needle_pos);
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const auto c_l_u32 = Poco::Unicode::toLower(c_u32);
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const auto c_u_u32 = Poco::Unicode::toUpper(c_u32);
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const auto dst_l_len = static_cast<UInt8>(utf8.convert(c_l_u32, l_seq, sizeof(l_seq)));
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const auto dst_u_len = static_cast<UInt8>(utf8.convert(c_u_u32, u_seq, sizeof(u_seq)));
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/// @note Unicode standard states it is a rare but possible occasion
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if (!(dst_l_len == dst_u_len && dst_u_len == src_len))
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throw DB::Exception{
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"UTF8 sequences with different lowercase and uppercase lengths are not supported",
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DB::ErrorCodes::UNSUPPORTED_PARAMETER
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};
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cache_actual_len += src_len;
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if (cache_actual_len < n)
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cache_valid_len += src_len;
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for (std::size_t j = 0; j < src_len && i < n; ++j, ++i)
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{
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cachel = _mm_srli_si128(cachel, 1);
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cacheu = _mm_srli_si128(cacheu, 1);
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if (needle_pos != needle_end)
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{
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cachel = _mm_insert_epi8(cachel, l_seq[j], n - 1);
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cacheu = _mm_insert_epi8(cacheu, u_seq[j], n - 1);
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cachemask |= 1 << i;
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++needle_pos;
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}
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}
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}
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#endif
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}
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bool compare(const UInt8 * pos) const
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{
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static const Poco::UTF8Encoding utf8;
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#if defined(__x86_64__)
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if (page_safe(pos))
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{
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const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(pos));
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const auto v_against_l = _mm_cmpeq_epi8(v_haystack, cachel);
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const auto v_against_u = _mm_cmpeq_epi8(v_haystack, cacheu);
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const auto v_against_l_or_u = _mm_or_si128(v_against_l, v_against_u);
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const auto mask = _mm_movemask_epi8(v_against_l_or_u);
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if (0xffff == cachemask)
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{
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if (mask == cachemask)
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{
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pos += cache_valid_len;
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auto needle_pos = needle + cache_valid_len;
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while (needle_pos < needle_end &&
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Poco::Unicode::toLower(utf8.convert(pos)) ==
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Poco::Unicode::toLower(utf8.convert(needle_pos)))
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{
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/// @note assuming sequences for lowercase and uppercase have exact same length
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const auto len = DB::UTF8::seqLength(*pos);
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pos += len, needle_pos += len;
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}
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if (needle_pos == needle_end)
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return true;
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}
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}
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else if ((mask & cachemask) == cachemask)
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return true;
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return false;
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}
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#endif
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if (*pos == l || *pos == u)
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{
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pos += first_needle_symbol_is_ascii;
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auto needle_pos = needle + first_needle_symbol_is_ascii;
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while (needle_pos < needle_end &&
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Poco::Unicode::toLower(utf8.convert(pos)) ==
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Poco::Unicode::toLower(utf8.convert(needle_pos)))
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{
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const auto len = DB::UTF8::seqLength(*pos);
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pos += len, needle_pos += len;
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}
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if (needle_pos == needle_end)
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return true;
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}
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return false;
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}
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const UInt8 * search(const UInt8 * haystack, const UInt8 * const haystack_end) const
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{
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if (0 == needle_size)
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return haystack;
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static const Poco::UTF8Encoding utf8;
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while (haystack < haystack_end)
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{
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#if defined(__x86_64__)
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if (haystack + n <= haystack_end && page_safe(haystack))
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{
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const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(haystack));
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const auto v_against_l = _mm_cmpeq_epi8(v_haystack, patl);
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const auto v_against_u = _mm_cmpeq_epi8(v_haystack, patu);
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const auto v_against_l_or_u = _mm_or_si128(v_against_l, v_against_u);
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const auto mask = _mm_movemask_epi8(v_against_l_or_u);
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if (mask == 0)
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{
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haystack += n;
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DB::UTF8::syncForward(haystack, haystack_end);
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continue;
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}
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const auto offset = __builtin_ctz(mask);
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haystack += offset;
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if (haystack < haystack_end && haystack + n <= haystack_end && page_safe(haystack))
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{
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const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(haystack));
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const auto v_against_l = _mm_cmpeq_epi8(v_haystack, cachel);
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const auto v_against_u = _mm_cmpeq_epi8(v_haystack, cacheu);
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const auto v_against_l_or_u = _mm_or_si128(v_against_l, v_against_u);
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const auto mask = _mm_movemask_epi8(v_against_l_or_u);
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if (0xffff == cachemask)
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{
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if (mask == cachemask)
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{
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auto haystack_pos = haystack + cache_valid_len;
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auto needle_pos = needle + cache_valid_len;
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while (haystack_pos < haystack_end && needle_pos < needle_end &&
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Poco::Unicode::toLower(utf8.convert(haystack_pos)) ==
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Poco::Unicode::toLower(utf8.convert(needle_pos)))
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{
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/// @note assuming sequences for lowercase and uppercase have exact same length
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const auto len = DB::UTF8::seqLength(*haystack_pos);
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haystack_pos += len, needle_pos += len;
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}
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if (needle_pos == needle_end)
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return haystack;
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}
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}
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else if ((mask & cachemask) == cachemask)
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return haystack;
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/// first octet was ok, but not the first 16, move to start of next sequence and reapply
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haystack += DB::UTF8::seqLength(*haystack);
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continue;
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}
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}
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#endif
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if (haystack == haystack_end)
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return haystack_end;
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if (*haystack == l || *haystack == u)
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{
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auto haystack_pos = haystack + first_needle_symbol_is_ascii;
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auto needle_pos = needle + first_needle_symbol_is_ascii;
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while (haystack_pos < haystack_end && needle_pos < needle_end &&
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Poco::Unicode::toLower(utf8.convert(haystack_pos)) ==
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Poco::Unicode::toLower(utf8.convert(needle_pos)))
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{
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const auto len = DB::UTF8::seqLength(*haystack_pos);
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haystack_pos += len, needle_pos += len;
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}
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if (needle_pos == needle_end)
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return haystack;
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}
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/// advance to the start of the next sequence
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haystack += DB::UTF8::seqLength(*haystack);
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}
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return haystack_end;
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}
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const UInt8 * search(const UInt8 * haystack, const size_t haystack_size) const
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{
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return search(haystack, haystack + haystack_size);
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}
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};
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/// Case-insensitive ASCII searcher
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template <>
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class StringSearcher<false, true> : private StringSearcherBase
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{
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private:
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/// string to be searched for
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const UInt8 * const needle;
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const std::size_t needle_size;
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const UInt8 * const needle_end = needle + needle_size;
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/// lower and uppercase variants of the first character in `needle`
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UInt8 l{};
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UInt8 u{};
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#if defined(__x86_64__)
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/// vectors filled with `l` and `u`, for determining leftmost position of the first symbol
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__m128i patl, patu;
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/// lower and uppercase vectors of first 16 characters of `needle`
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__m128i cachel = _mm_setzero_si128(), cacheu = _mm_setzero_si128();
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int cachemask{};
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#endif
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public:
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StringSearcher(const char * const needle_, const std::size_t needle_size)
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: needle{reinterpret_cast<const UInt8 *>(needle_)}, needle_size{needle_size}
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{
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if (0 == needle_size)
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return;
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l = static_cast<UInt8>(std::tolower(*needle));
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u = static_cast<UInt8>(std::toupper(*needle));
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#if defined(__x86_64__)
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patl = _mm_set1_epi8(l);
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patu = _mm_set1_epi8(u);
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auto needle_pos = needle;
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for (const auto i : ext::range(0, n))
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{
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cachel = _mm_srli_si128(cachel, 1);
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cacheu = _mm_srli_si128(cacheu, 1);
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if (needle_pos != needle_end)
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{
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cachel = _mm_insert_epi8(cachel, std::tolower(*needle_pos), n - 1);
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cacheu = _mm_insert_epi8(cacheu, std::toupper(*needle_pos), n - 1);
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cachemask |= 1 << i;
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++needle_pos;
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}
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}
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#endif
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}
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bool compare(const UInt8 * pos) const
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{
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#if defined(__x86_64__)
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if (page_safe(pos))
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{
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const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(pos));
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const auto v_against_l = _mm_cmpeq_epi8(v_haystack, cachel);
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const auto v_against_u = _mm_cmpeq_epi8(v_haystack, cacheu);
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const auto v_against_l_or_u = _mm_or_si128(v_against_l, v_against_u);
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const auto mask = _mm_movemask_epi8(v_against_l_or_u);
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if (0xffff == cachemask)
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{
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if (mask == cachemask)
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{
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pos += n;
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auto needle_pos = needle + n;
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while (needle_pos < needle_end && std::tolower(*pos) == std::tolower(*needle_pos))
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++pos, ++needle_pos;
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if (needle_pos == needle_end)
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return true;
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}
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}
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else if ((mask & cachemask) == cachemask)
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return true;
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return false;
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}
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#endif
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if (*pos == l || *pos == u)
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{
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++pos;
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auto needle_pos = needle + 1;
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while (needle_pos < needle_end && std::tolower(*pos) == std::tolower(*needle_pos))
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++pos, ++needle_pos;
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if (needle_pos == needle_end)
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return true;
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}
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return false;
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}
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const UInt8 * search(const UInt8 * haystack, const UInt8 * const haystack_end) const
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{
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if (0 == needle_size)
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return haystack;
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while (haystack < haystack_end)
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{
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#if defined(__x86_64__)
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if (haystack + n <= haystack_end && page_safe(haystack))
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{
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const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(haystack));
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const auto v_against_l = _mm_cmpeq_epi8(v_haystack, patl);
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const auto v_against_u = _mm_cmpeq_epi8(v_haystack, patu);
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const auto v_against_l_or_u = _mm_or_si128(v_against_l, v_against_u);
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const auto mask = _mm_movemask_epi8(v_against_l_or_u);
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if (mask == 0)
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{
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haystack += n;
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continue;
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}
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const auto offset = __builtin_ctz(mask);
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haystack += offset;
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if (haystack < haystack_end && haystack + n <= haystack_end && page_safe(haystack))
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{
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const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(haystack));
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const auto v_against_l = _mm_cmpeq_epi8(v_haystack, cachel);
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const auto v_against_u = _mm_cmpeq_epi8(v_haystack, cacheu);
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const auto v_against_l_or_u = _mm_or_si128(v_against_l, v_against_u);
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const auto mask = _mm_movemask_epi8(v_against_l_or_u);
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if (0xffff == cachemask)
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{
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if (mask == cachemask)
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{
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auto haystack_pos = haystack + n;
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auto needle_pos = needle + n;
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while (haystack_pos < haystack_end && needle_pos < needle_end &&
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std::tolower(*haystack_pos) == std::tolower(*needle_pos))
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++haystack_pos, ++needle_pos;
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if (needle_pos == needle_end)
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return haystack;
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}
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}
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else if ((mask & cachemask) == cachemask)
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return haystack;
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++haystack;
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continue;
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}
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}
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#endif
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if (haystack == haystack_end)
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return haystack_end;
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if (*haystack == l || *haystack == u)
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{
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auto haystack_pos = haystack + 1;
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auto needle_pos = needle + 1;
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while (haystack_pos < haystack_end && needle_pos < needle_end &&
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std::tolower(*haystack_pos) == std::tolower(*needle_pos))
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++haystack_pos, ++needle_pos;
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if (needle_pos == needle_end)
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return haystack;
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}
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++haystack;
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}
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return haystack_end;
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}
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const UInt8 * search(const UInt8 * haystack, const size_t haystack_size) const
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{
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return search(haystack, haystack + haystack_size);
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}
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};
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|
||
|
||
/// Case-sensitive searcher (both ASCII and UTF-8)
|
||
template <bool ASCII>
|
||
class StringSearcher<true, ASCII> : private StringSearcherBase
|
||
{
|
||
private:
|
||
/// string to be searched for
|
||
const UInt8 * const needle;
|
||
const std::size_t needle_size;
|
||
const UInt8 * const needle_end = needle + needle_size;
|
||
/// first character in `needle`
|
||
UInt8 first{};
|
||
|
||
#if defined(__x86_64__)
|
||
/// vector filled `first` for determining leftmost position of the first symbol
|
||
__m128i pattern;
|
||
/// vector of first 16 characters of `needle`
|
||
__m128i cache = _mm_setzero_si128();
|
||
int cachemask{};
|
||
#endif
|
||
|
||
public:
|
||
StringSearcher(const char * const needle_, const std::size_t needle_size)
|
||
: needle{reinterpret_cast<const UInt8 *>(needle_)}, needle_size{needle_size}
|
||
{
|
||
if (0 == needle_size)
|
||
return;
|
||
|
||
first = *needle;
|
||
|
||
#if defined(__x86_64__)
|
||
pattern = _mm_set1_epi8(first);
|
||
|
||
auto needle_pos = needle;
|
||
|
||
for (const auto i : ext::range(0, n))
|
||
{
|
||
cache = _mm_srli_si128(cache, 1);
|
||
|
||
if (needle_pos != needle_end)
|
||
{
|
||
cache = _mm_insert_epi8(cache, *needle_pos, n - 1);
|
||
cachemask |= 1 << i;
|
||
++needle_pos;
|
||
}
|
||
}
|
||
#endif
|
||
}
|
||
|
||
bool compare(const UInt8 * pos) const
|
||
{
|
||
#if defined(__x86_64__)
|
||
if (page_safe(pos))
|
||
{
|
||
const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(pos));
|
||
const auto v_against_cache = _mm_cmpeq_epi8(v_haystack, cache);
|
||
const auto mask = _mm_movemask_epi8(v_against_cache);
|
||
|
||
if (0xffff == cachemask)
|
||
{
|
||
if (mask == cachemask)
|
||
{
|
||
pos += n;
|
||
auto needle_pos = needle + n;
|
||
|
||
while (needle_pos < needle_end && *pos == *needle_pos)
|
||
++pos, ++needle_pos;
|
||
|
||
if (needle_pos == needle_end)
|
||
return true;
|
||
}
|
||
}
|
||
else if ((mask & cachemask) == cachemask)
|
||
return true;
|
||
|
||
return false;
|
||
}
|
||
#endif
|
||
|
||
if (*pos == first)
|
||
{
|
||
++pos;
|
||
auto needle_pos = needle + 1;
|
||
|
||
while (needle_pos < needle_end && *pos == *needle_pos)
|
||
++pos, ++needle_pos;
|
||
|
||
if (needle_pos == needle_end)
|
||
return true;
|
||
}
|
||
|
||
return false;
|
||
}
|
||
|
||
const UInt8 * search(const UInt8 * haystack, const UInt8 * const haystack_end) const
|
||
{
|
||
if (0 == needle_size)
|
||
return haystack;
|
||
|
||
while (haystack < haystack_end)
|
||
{
|
||
#if defined(__x86_64__)
|
||
if (haystack + n <= haystack_end && page_safe(haystack))
|
||
{
|
||
/// find first character
|
||
const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(haystack));
|
||
const auto v_against_pattern = _mm_cmpeq_epi8(v_haystack, pattern);
|
||
|
||
const auto mask = _mm_movemask_epi8(v_against_pattern);
|
||
|
||
/// first character not present in 16 octets starting at `haystack`
|
||
if (mask == 0)
|
||
{
|
||
haystack += n;
|
||
continue;
|
||
}
|
||
|
||
const auto offset = __builtin_ctz(mask);
|
||
haystack += offset;
|
||
|
||
if (haystack < haystack_end && haystack + n <= haystack_end && page_safe(haystack))
|
||
{
|
||
/// check for first 16 octets
|
||
const auto v_haystack = _mm_loadu_si128(reinterpret_cast<const __m128i *>(haystack));
|
||
const auto v_against_cache = _mm_cmpeq_epi8(v_haystack, cache);
|
||
const auto mask = _mm_movemask_epi8(v_against_cache);
|
||
|
||
if (0xffff == cachemask)
|
||
{
|
||
if (mask == cachemask)
|
||
{
|
||
auto haystack_pos = haystack + n;
|
||
auto needle_pos = needle + n;
|
||
|
||
while (haystack_pos < haystack_end && needle_pos < needle_end &&
|
||
*haystack_pos == *needle_pos)
|
||
++haystack_pos, ++needle_pos;
|
||
|
||
if (needle_pos == needle_end)
|
||
return haystack;
|
||
}
|
||
}
|
||
else if ((mask & cachemask) == cachemask)
|
||
return haystack;
|
||
|
||
++haystack;
|
||
continue;
|
||
}
|
||
}
|
||
#endif
|
||
|
||
if (haystack == haystack_end)
|
||
return haystack_end;
|
||
|
||
if (*haystack == first)
|
||
{
|
||
auto haystack_pos = haystack + 1;
|
||
auto needle_pos = needle + 1;
|
||
|
||
while (haystack_pos < haystack_end && needle_pos < needle_end &&
|
||
*haystack_pos == *needle_pos)
|
||
++haystack_pos, ++needle_pos;
|
||
|
||
if (needle_pos == needle_end)
|
||
return haystack;
|
||
}
|
||
|
||
++haystack;
|
||
}
|
||
|
||
return haystack_end;
|
||
}
|
||
|
||
const UInt8 * search(const UInt8 * haystack, const size_t haystack_size) const
|
||
{
|
||
return search(haystack, haystack + haystack_size);
|
||
}
|
||
};
|
||
|
||
|
||
using ASCIICaseSensitiveStringSearcher = StringSearcher<true, true>;
|
||
using ASCIICaseInsensitiveStringSearcher = StringSearcher<false, true>;
|
||
using UTF8CaseSensitiveStringSearcher = StringSearcher<true, false>;
|
||
using UTF8CaseInsensitiveStringSearcher = StringSearcher<false, false>;
|
||
|
||
|
||
/** Используют функции из libc.
|
||
* Имеет смысл использовать для коротких строк, когда требуется дешёвая инициализация.
|
||
* Нет варианта для регистронезависимого поиска UTF-8 строк.
|
||
* Требуется, чтобы за концом строк был нулевой байт.
|
||
*/
|
||
|
||
struct LibCASCIICaseSensitiveStringSearcher
|
||
{
|
||
const char * const needle;
|
||
const size_t needle_size;
|
||
|
||
LibCASCIICaseSensitiveStringSearcher(const char * const needle, const size_t needle_size)
|
||
: needle(needle), needle_size(needle_size) {}
|
||
|
||
const UInt8 * search(const UInt8 * haystack, const UInt8 * const haystack_end) const
|
||
{
|
||
auto res = strstr(reinterpret_cast<const char *>(haystack), reinterpret_cast<const char *>(needle));
|
||
if (!res)
|
||
return haystack_end;
|
||
return reinterpret_cast<const UInt8 *>(res);
|
||
}
|
||
|
||
const UInt8 * search(const UInt8 * haystack, const size_t haystack_size) const
|
||
{
|
||
return search(haystack, haystack + haystack_size);
|
||
}
|
||
};
|
||
|
||
struct LibCASCIICaseInsensitiveStringSearcher
|
||
{
|
||
const char * const needle;
|
||
const size_t needle_size;
|
||
|
||
LibCASCIICaseInsensitiveStringSearcher(const char * const needle, const size_t needle_size)
|
||
: needle(needle), needle_size(needle_size) {}
|
||
|
||
const UInt8 * search(const UInt8 * haystack, const UInt8 * const haystack_end) const
|
||
{
|
||
auto res = strcasestr(reinterpret_cast<const char *>(haystack), reinterpret_cast<const char *>(needle));
|
||
if (!res)
|
||
return haystack_end;
|
||
return reinterpret_cast<const UInt8 *>(res);
|
||
}
|
||
|
||
const UInt8 * search(const UInt8 * haystack, const size_t haystack_size) const
|
||
{
|
||
return search(haystack, haystack + haystack_size);
|
||
}
|
||
};
|
||
|
||
|
||
}
|