mirror of
https://github.com/simdjson/simdjson
synced 2026-06-08 17:27:07 +00:00
John Keiser
199 lines
7.7 KiB
C++
199 lines
7.7 KiB
C++
#ifndef SIMDJSON_SIMDUTF8CHECK_HASWELL_H
|
|
#define SIMDJSON_SIMDUTF8CHECK_HASWELL_H
|
|
|
|
#include "simdjson/portability.h"
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
|
|
#ifdef IS_X86_64
|
|
/*
|
|
* legal utf-8 byte sequence
|
|
* http://www.unicode.org/versions/Unicode6.0.0/ch03.pdf - page 94
|
|
*
|
|
* Code Points 1st 2s 3s 4s
|
|
* U+0000..U+007F 00..7F
|
|
* U+0080..U+07FF C2..DF 80..BF
|
|
* U+0800..U+0FFF E0 A0..BF 80..BF
|
|
* U+1000..U+CFFF E1..EC 80..BF 80..BF
|
|
* U+D000..U+D7FF ED 80..9F 80..BF
|
|
* U+E000..U+FFFF EE..EF 80..BF 80..BF
|
|
* U+10000..U+3FFFF F0 90..BF 80..BF 80..BF
|
|
* U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF
|
|
* U+100000..U+10FFFF F4 80..8F 80..BF 80..BF
|
|
*
|
|
*/
|
|
|
|
// all byte values must be no larger than 0xF4
|
|
|
|
TARGET_HASWELL
|
|
namespace simdjson {
|
|
static inline __m256i push_last_byte_of_a_to_b(__m256i a, __m256i b) {
|
|
return _mm256_alignr_epi8(b, _mm256_permute2x128_si256(a, b, 0x21), 15);
|
|
}
|
|
|
|
static inline __m256i push_last_2bytes_of_a_to_b(__m256i a, __m256i b) {
|
|
return _mm256_alignr_epi8(b, _mm256_permute2x128_si256(a, b, 0x21), 14);
|
|
}
|
|
|
|
// all byte values must be no larger than 0xF4
|
|
static inline void avx_check_smaller_than_0xF4(__m256i current_bytes,
|
|
__m256i *has_error) {
|
|
// unsigned, saturates to 0 below max
|
|
*has_error = _mm256_or_si256(
|
|
*has_error, _mm256_subs_epu8(current_bytes, _mm256_set1_epi8(0xF4u)));
|
|
}
|
|
|
|
static inline __m256i avx_continuation_lengths(__m256i high_nibbles) {
|
|
return _mm256_shuffle_epi8(
|
|
_mm256_setr_epi8(1, 1, 1, 1, 1, 1, 1, 1, // 0xxx (ASCII)
|
|
0, 0, 0, 0, // 10xx (continuation)
|
|
2, 2, // 110x
|
|
3, // 1110
|
|
4, // 1111, next should be 0 (not checked here)
|
|
1, 1, 1, 1, 1, 1, 1, 1, // 0xxx (ASCII)
|
|
0, 0, 0, 0, // 10xx (continuation)
|
|
2, 2, // 110x
|
|
3, // 1110
|
|
4 // 1111, next should be 0 (not checked here)
|
|
),
|
|
high_nibbles);
|
|
}
|
|
|
|
static inline __m256i avx_carry_continuations(__m256i initial_lengths,
|
|
__m256i previous_carries) {
|
|
|
|
__m256i right1 = _mm256_subs_epu8(
|
|
push_last_byte_of_a_to_b(previous_carries, initial_lengths),
|
|
_mm256_set1_epi8(1));
|
|
__m256i sum = _mm256_add_epi8(initial_lengths, right1);
|
|
|
|
__m256i right2 = _mm256_subs_epu8(
|
|
push_last_2bytes_of_a_to_b(previous_carries, sum), _mm256_set1_epi8(2));
|
|
return _mm256_add_epi8(sum, right2);
|
|
}
|
|
|
|
static inline void avx_check_continuations(__m256i initial_lengths,
|
|
__m256i carries,
|
|
__m256i *has_error) {
|
|
|
|
// overlap || underlap
|
|
// carry > length && length > 0 || !(carry > length) && !(length > 0)
|
|
// (carries > length) == (lengths > 0)
|
|
__m256i overunder = _mm256_cmpeq_epi8(
|
|
_mm256_cmpgt_epi8(carries, initial_lengths),
|
|
_mm256_cmpgt_epi8(initial_lengths, _mm256_setzero_si256()));
|
|
|
|
*has_error = _mm256_or_si256(*has_error, overunder);
|
|
}
|
|
|
|
// when 0xED is found, next byte must be no larger than 0x9F
|
|
// when 0xF4 is found, next byte must be no larger than 0x8F
|
|
// next byte must be continuation, ie sign bit is set, so signed < is ok
|
|
static inline void avx_check_first_continuation_max(__m256i current_bytes,
|
|
__m256i off1_current_bytes,
|
|
__m256i *has_error) {
|
|
__m256i maskED =
|
|
_mm256_cmpeq_epi8(off1_current_bytes, _mm256_set1_epi8(0xEDu));
|
|
__m256i maskF4 =
|
|
_mm256_cmpeq_epi8(off1_current_bytes, _mm256_set1_epi8(0xF4u));
|
|
|
|
__m256i badfollowED = _mm256_and_si256(
|
|
_mm256_cmpgt_epi8(current_bytes, _mm256_set1_epi8(0x9Fu)), maskED);
|
|
__m256i badfollowF4 = _mm256_and_si256(
|
|
_mm256_cmpgt_epi8(current_bytes, _mm256_set1_epi8(0x8Fu)), maskF4);
|
|
|
|
*has_error =
|
|
_mm256_or_si256(*has_error, _mm256_or_si256(badfollowED, badfollowF4));
|
|
}
|
|
|
|
// map off1_hibits => error condition
|
|
// hibits off1 cur
|
|
// C => < C2 && true
|
|
// E => < E1 && < A0
|
|
// F => < F1 && < 90
|
|
// else false && false
|
|
static inline void avx_check_overlong(__m256i current_bytes,
|
|
__m256i off1_current_bytes,
|
|
__m256i hibits, __m256i previous_hibits,
|
|
__m256i *has_error) {
|
|
__m256i off1_hibits = push_last_byte_of_a_to_b(previous_hibits, hibits);
|
|
__m256i initial_mins = _mm256_shuffle_epi8(
|
|
_mm256_setr_epi8(-128, -128, -128, -128, -128, -128, -128, -128, -128,
|
|
-128, -128, -128, // 10xx => false
|
|
0xC2u, -128, // 110x
|
|
0xE1u, // 1110
|
|
0xF1u, // 1111
|
|
-128, -128, -128, -128, -128, -128, -128, -128, -128,
|
|
-128, -128, -128, // 10xx => false
|
|
0xC2u, -128, // 110x
|
|
0xE1u, // 1110
|
|
0xF1u), // 1111
|
|
off1_hibits);
|
|
|
|
__m256i initial_under = _mm256_cmpgt_epi8(initial_mins, off1_current_bytes);
|
|
|
|
__m256i second_mins = _mm256_shuffle_epi8(
|
|
_mm256_setr_epi8(-128, -128, -128, -128, -128, -128, -128, -128, -128,
|
|
-128, -128, -128, // 10xx => false
|
|
127, 127, // 110x => true
|
|
0xA0u, // 1110
|
|
0x90u, // 1111
|
|
-128, -128, -128, -128, -128, -128, -128, -128, -128,
|
|
-128, -128, -128, // 10xx => false
|
|
127, 127, // 110x => true
|
|
0xA0u, // 1110
|
|
0x90u), // 1111
|
|
off1_hibits);
|
|
__m256i second_under = _mm256_cmpgt_epi8(second_mins, current_bytes);
|
|
*has_error = _mm256_or_si256(*has_error,
|
|
_mm256_and_si256(initial_under, second_under));
|
|
}
|
|
|
|
struct avx_processed_utf_bytes {
|
|
__m256i raw_bytes;
|
|
__m256i high_nibbles;
|
|
__m256i carried_continuations;
|
|
};
|
|
|
|
static inline void avx_count_nibbles(__m256i bytes,
|
|
struct avx_processed_utf_bytes *answer) {
|
|
answer->raw_bytes = bytes;
|
|
answer->high_nibbles =
|
|
_mm256_and_si256(_mm256_srli_epi16(bytes, 4), _mm256_set1_epi8(0x0F));
|
|
}
|
|
|
|
// check whether the current bytes are valid UTF-8
|
|
// at the end of the function, previous gets updated
|
|
static inline struct avx_processed_utf_bytes
|
|
avx_check_utf8_bytes(__m256i current_bytes,
|
|
struct avx_processed_utf_bytes *previous,
|
|
__m256i *has_error) {
|
|
struct avx_processed_utf_bytes pb {};
|
|
avx_count_nibbles(current_bytes, &pb);
|
|
|
|
avx_check_smaller_than_0xF4(current_bytes, has_error);
|
|
|
|
__m256i initial_lengths = avx_continuation_lengths(pb.high_nibbles);
|
|
|
|
pb.carried_continuations =
|
|
avx_carry_continuations(initial_lengths, previous->carried_continuations);
|
|
|
|
avx_check_continuations(initial_lengths, pb.carried_continuations, has_error);
|
|
|
|
__m256i off1_current_bytes =
|
|
push_last_byte_of_a_to_b(previous->raw_bytes, pb.raw_bytes);
|
|
avx_check_first_continuation_max(current_bytes, off1_current_bytes,
|
|
has_error);
|
|
|
|
avx_check_overlong(current_bytes, off1_current_bytes, pb.high_nibbles,
|
|
previous->high_nibbles, has_error);
|
|
return pb;
|
|
}
|
|
} // namespace simdjson
|
|
UNTARGET_REGION // haswell
|
|
|
|
#endif // IS_X86_64
|
|
|
|
#endif
|