mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-14 02:12:21 +00:00
84 lines
2.2 KiB
C++
84 lines
2.2 KiB
C++
#pragma once
|
|
|
|
#include <Core/Types.h>
|
|
#include <Common/BitHelpers.h>
|
|
|
|
#ifdef __SSE2__
|
|
#include <emmintrin.h>
|
|
#endif
|
|
|
|
|
|
namespace DB
|
|
{
|
|
|
|
|
|
namespace UTF8
|
|
{
|
|
|
|
static const UInt8 CONTINUATION_OCTET_MASK = 0b11000000u;
|
|
static const UInt8 CONTINUATION_OCTET = 0b10000000u;
|
|
|
|
/// return true if `octet` binary repr starts with 10 (octet is a UTF-8 sequence continuation)
|
|
inline bool isContinuationOctet(const UInt8 octet)
|
|
{
|
|
return (octet & CONTINUATION_OCTET_MASK) == CONTINUATION_OCTET;
|
|
}
|
|
|
|
/// moves `s` backward until either first non-continuation octet or begin
|
|
inline void syncBackward(const UInt8 * & s, const UInt8 * const begin)
|
|
{
|
|
while (isContinuationOctet(*s) && s > begin)
|
|
--s;
|
|
}
|
|
|
|
/// moves `s` forward until either first non-continuation octet or string end is met
|
|
inline void syncForward(const UInt8 * & s, const UInt8 * const end)
|
|
{
|
|
while (s < end && isContinuationOctet(*s))
|
|
++s;
|
|
}
|
|
|
|
/// returns UTF-8 code point sequence length judging by it's first octet
|
|
inline size_t seqLength(const UInt8 first_octet)
|
|
{
|
|
if (first_octet < 0x80u)
|
|
return 1;
|
|
|
|
const size_t bits = 8;
|
|
const auto first_zero = bitScanReverse(static_cast<UInt8>(~first_octet));
|
|
|
|
return bits - 1 - first_zero;
|
|
}
|
|
|
|
inline size_t countCodePoints(const UInt8 * data, size_t size)
|
|
{
|
|
size_t res = 0;
|
|
const auto end = data + size;
|
|
|
|
#ifdef __SSE2__
|
|
constexpr auto bytes_sse = sizeof(__m128i);
|
|
const auto src_end_sse = data + size / bytes_sse * bytes_sse;
|
|
|
|
const auto threshold = _mm_set1_epi8(0xBF);
|
|
|
|
for (; data < src_end_sse; data += bytes_sse)
|
|
res += __builtin_popcount(_mm_movemask_epi8(
|
|
_mm_cmpgt_epi8(_mm_loadu_si128(reinterpret_cast<const __m128i *>(data)), threshold)));
|
|
#endif
|
|
|
|
for (; data < end; ++data) /// Skip UTF-8 continuation bytes.
|
|
res += static_cast<Int8>(*data) > static_cast<Int8>(0xBF);
|
|
|
|
return res;
|
|
}
|
|
|
|
/// returns UTF-8 wcswidth. Invalid sequence is treated as zero width character.
|
|
/// `prefix` is used to compute the `\t` width which extends the string before
|
|
/// and include `\t` to the nearest longer length with multiple of eight.
|
|
size_t computeWidth(const UInt8 * data, size_t size, size_t prefix = 0) noexcept;
|
|
|
|
}
|
|
|
|
|
|
}
|