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sonic/native/scanning.c
liu 8639e93666
fix: validate on demand at first for GetByPath and NewRaw (#389)
* feat(ast): validate the demanded fields for ast Get

* fix: add more tests

* fix: check invalid path type

* fix(arm): make return error when skip invalid exponent

* fix(arm): skip object and array with validate

* fix: check input json in NewRaw

* fix: validate the path in native c

* chore: add licenses

* fix: panic when invalid path

* fix: add Get Full json benchmark

* fix(arm): use fast skip besides the ondemand fields

* chore codes

---------

Co-authored-by: liuqiang <liuqiang.06@bytedance.com>
2023-03-22 19:23:44 +08:00

1941 lines
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57 KiB
C

/*
* Copyright 2021 ByteDance Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "native.h"
#include "utf8.h"
#include "utils.h"
static const uint64_t ODD_MASK = 0xaaaaaaaaaaaaaaaa;
static const uint64_t EVEN_MASK = 0x5555555555555555;
// NOTE: mask referenced from decoder/decoder.go
static const uint64_t MASK_VALIDATE_STRING = 1ull << 5;
static const uint64_t MASK_ALLOW_CONTROL = 1ull << 31;
static const double P10_TAB[23] = {
/* <= the connvertion to double is not exact when less than 1 => */ 1e-000,
1e+001, 1e+002, 1e+003, 1e+004, 1e+005, 1e+006, 1e+007, 1e+008, 1e+009, 1e+010,
1e+011, 1e+012, 1e+013, 1e+014, 1e+015, 1e+016, 1e+017, 1e+018, 1e+019, 1e+020,
1e+021, 1e+022 /* <= the connvertion to double is not exact when larger, => */
};
static inline uint64_t add32(uint64_t v1, uint64_t v2, uint64_t *vo) {
uint32_t v;
uint32_t c = __builtin_uadd_overflow((uint32_t)v1, (uint32_t)v2, &v);
/* set the carry */
*vo = c;
return v;
}
static inline uint64_t add64(uint64_t v1, uint64_t v2, uint64_t *vo) {
unsigned long long v;
uint64_t c = __builtin_uaddll_overflow(v1, v2, &v);
/* set the carry */
*vo = c;
return v;
}
static inline char isspace(char ch) {
return ch == ' ' || ch == '\r' || ch == '\n' | ch == '\t';
}
const int MASK_USE_NUMBER = 1<<1;
static inline void vdigits(const GoString *src, long *p, JsonState *ret, uint64_t flag) {
--*p;
if (flag & MASK_USE_NUMBER) {
long i = skip_number(src, p);
if (i < 0) {
ret->vt = i;
return;
}
ret->vt = V_DOUBLE;
ret->ep = i;
return;
}
vnumber(src, p, ret);
}
static inline char advance_ns(const GoString *src, long *p) {
size_t vi = *p;
size_t nb = src->len;
const char * sp = src->buf;
/* it's likely to run into non-spaces within a few
* characters, so test up to 4 characters manually */
if (vi < nb && !isspace(sp[vi])) goto nospace; else vi++;
if (vi < nb && !isspace(sp[vi])) goto nospace; else vi++;
if (vi < nb && !isspace(sp[vi])) goto nospace; else vi++;
if (vi < nb && !isspace(sp[vi])) goto nospace; else vi++;
/* check EOF */
if (vi >= nb) {
*p = vi;
return 0;
}
/* too many spaces, use SIMD to search for characters */
if ((vi = lspace(sp, nb, vi)) >= nb) {
return 0;
}
nospace:
*p = vi + 1;
return src->buf[vi];
}
static inline int64_t advance_dword(const GoString *src, long *p, long dec, int64_t ret, uint32_t val) {
if (*p > src->len + dec - 4) {
*p = src->len;
return -ERR_EOF;
} else if (*(uint32_t *)(src->buf + *p - dec) == val) {
*p += 4 - dec;
return ret;
} else {
*p -= dec;
for (int i = 0; src->buf[*p] == (val & 0xff) && i < 4; i++, ++*p) { val >>= 8; }
return -ERR_INVAL;
}
}
static inline ssize_t advance_string_default(const GoString *src, long p, int64_t *ep) {
char ch;
uint64_t es;
uint64_t fe;
uint64_t os;
uint64_t m0;
uint64_t m1;
uint64_t cr = 0;
/* prevent out-of-bounds accessing */
if (unlikely(src->len == p)) {
return -ERR_EOF;
}
/* buffer pointers */
size_t nb = src->len;
const char * sp = src->buf;
const char * ss = src->buf;
#define ep_init() *ep = -1;
#define ep_setc() ep_setx(sp - ss - 1)
#define ep_setx(x) if (*ep == -1) { *ep = (x); }
/* seek to `p` */
nb -= p;
sp += p;
ep_init()
#if USE_AVX2
/* initialize vectors */
__m256i v0;
__m256i v1;
__m256i q0;
__m256i q1;
__m256i x0;
__m256i x1;
__m256i cq = _mm256_set1_epi8('"');
__m256i cx = _mm256_set1_epi8('\\');
/* partial masks */
uint32_t s0;
uint32_t s1;
uint32_t t0;
uint32_t t1;
#else
/* initialize vectors */
__m128i v0;
__m128i v1;
__m128i v2;
__m128i v3;
__m128i q0;
__m128i q1;
__m128i q2;
__m128i q3;
__m128i x0;
__m128i x1;
__m128i x2;
__m128i x3;
__m128i cq = _mm_set1_epi8('"');
__m128i cx = _mm_set1_epi8('\\');
/* partial masks */
uint32_t s0;
uint32_t s1;
uint32_t s2;
uint32_t s3;
uint32_t t0;
uint32_t t1;
uint32_t t2;
uint32_t t3;
#endif
#define m0_mask(add) \
m1 &= ~cr; \
fe = (m1 << 1) | cr; \
os = (m1 & ~fe) & ODD_MASK; \
es = add(os, m1, &cr) << 1; \
m0 &= ~(fe & (es ^ EVEN_MASK));
/* 64-byte SIMD loop */
while (likely(nb >= 64)) {
#if USE_AVX2
v0 = _mm256_loadu_si256 ((const void *)(sp + 0));
v1 = _mm256_loadu_si256 ((const void *)(sp + 32));
q0 = _mm256_cmpeq_epi8 (v0, cq);
q1 = _mm256_cmpeq_epi8 (v1, cq);
x0 = _mm256_cmpeq_epi8 (v0, cx);
x1 = _mm256_cmpeq_epi8 (v1, cx);
s0 = _mm256_movemask_epi8 (q0);
s1 = _mm256_movemask_epi8 (q1);
t0 = _mm256_movemask_epi8 (x0);
t1 = _mm256_movemask_epi8 (x1);
m0 = ((uint64_t)s1 << 32) | (uint64_t)s0;
m1 = ((uint64_t)t1 << 32) | (uint64_t)t0;
#else
v0 = _mm_loadu_si128 ((const void *)(sp + 0));
v1 = _mm_loadu_si128 ((const void *)(sp + 16));
v2 = _mm_loadu_si128 ((const void *)(sp + 32));
v3 = _mm_loadu_si128 ((const void *)(sp + 48));
q0 = _mm_cmpeq_epi8 (v0, cq);
q1 = _mm_cmpeq_epi8 (v1, cq);
q2 = _mm_cmpeq_epi8 (v2, cq);
q3 = _mm_cmpeq_epi8 (v3, cq);
x0 = _mm_cmpeq_epi8 (v0, cx);
x1 = _mm_cmpeq_epi8 (v1, cx);
x2 = _mm_cmpeq_epi8 (v2, cx);
x3 = _mm_cmpeq_epi8 (v3, cx);
s0 = _mm_movemask_epi8 (q0);
s1 = _mm_movemask_epi8 (q1);
s2 = _mm_movemask_epi8 (q2);
s3 = _mm_movemask_epi8 (q3);
t0 = _mm_movemask_epi8 (x0);
t1 = _mm_movemask_epi8 (x1);
t2 = _mm_movemask_epi8 (x2);
t3 = _mm_movemask_epi8 (x3);
m0 = ((uint64_t)s3 << 48) | ((uint64_t)s2 << 32) | ((uint64_t)s1 << 16) | (uint64_t)s0;
m1 = ((uint64_t)t3 << 48) | ((uint64_t)t2 << 32) | ((uint64_t)t1 << 16) | (uint64_t)t0;
#endif
/** update first quote position */
if (unlikely(m1 != 0)) {
ep_setx(sp - ss + __builtin_ctzll(m1))
}
/** mask all the escaped quotes */
if (unlikely(m1 != 0 || cr != 0)) {
m0_mask(add64)
}
/* check for end quote */
if (m0 != 0) {
return sp - ss + __builtin_ctzll(m0) + 1;
}
/* move to the next block */
sp += 64;
nb -= 64;
}
/* 32-byte SIMD round */
if (likely(nb >= 32)) {
#if USE_AVX2
v0 = _mm256_loadu_si256 ((const void *)sp);
q0 = _mm256_cmpeq_epi8 (v0, cq);
x0 = _mm256_cmpeq_epi8 (v0, cx);
s0 = _mm256_movemask_epi8 (q0);
t0 = _mm256_movemask_epi8 (x0);
m0 = (uint64_t)s0;
m1 = (uint64_t)t0;
#else
v0 = _mm_loadu_si128 ((const void *)(sp + 0));
v1 = _mm_loadu_si128 ((const void *)(sp + 16));
q0 = _mm_cmpeq_epi8 (v0, cq);
q1 = _mm_cmpeq_epi8 (v1, cq);
x0 = _mm_cmpeq_epi8 (v0, cx);
x1 = _mm_cmpeq_epi8 (v1, cx);
s0 = _mm_movemask_epi8 (q0);
s1 = _mm_movemask_epi8 (q1);
t0 = _mm_movemask_epi8 (x0);
t1 = _mm_movemask_epi8 (x1);
m0 = ((uint64_t)s1 << 16) | (uint64_t)s0;
m1 = ((uint64_t)t1 << 16) | (uint64_t)t0;
#endif
/** update first quote position */
if (unlikely(m1 != 0)) {
ep_setx(sp - ss + __builtin_ctzll(m1))
}
/** mask all the escaped quotes */
if (unlikely(m1 != 0 || cr != 0)) {
m0_mask(add32)
}
/* check for end quote */
if (m0 != 0) {
return sp - ss + __builtin_ctzll(m0) + 1;
}
/* move to the next block */
sp += 32;
nb -= 32;
}
/* check for carry */
if (unlikely(cr != 0)) {
if (nb == 0) {
return -ERR_EOF;
} else {
ep_setc()
sp++, nb--;
}
}
/* handle the remaining bytes with scalar code */
while (nb-- > 0 && (ch = *sp++) != '"') {
if (unlikely(ch == '\\')) {
if (nb == 0) {
return -ERR_EOF;
} else {
ep_setc()
sp++, nb--;
}
}
}
#undef ep_init
#undef ep_setc
#undef ep_setx
#undef m0_mask
/* check for quotes */
if (ch == '"') {
return sp - ss;
} else {
return -ERR_EOF;
}
}
#if USE_AVX2
static inline int _mm256_get_mask(__m256i v, __m256i t) {
return _mm256_movemask_epi8(_mm256_cmpeq_epi8(v, t));
}
// contrl char: 0x00 ~ 0x1F
static inline int _mm256_cchars_mask(__m256i v) {
__m256i e1 = _mm256_cmpgt_epi8 (v, _mm256_set1_epi8(-1));
__m256i e2 = _mm256_cmpgt_epi8 (v, _mm256_set1_epi8(31));
return _mm256_movemask_epi8 (_mm256_andnot_si256 (e2, e1));
}
// ascii: 0x00 ~ 0x7F
static inline int _mm256_nonascii_mask(__m256i v) {
return _mm256_movemask_epi8(v);
}
#endif
static inline int _mm_get_mask(__m128i v, __m128i t) {
return _mm_movemask_epi8(_mm_cmpeq_epi8(v, t));
}
// contrl char: 0x00 ~ 0x1F
static inline int _mm_cchars_mask(__m128i v) {
__m128i e1 = _mm_cmpgt_epi8 (v, _mm_set1_epi8(-1));
__m128i e2 = _mm_cmpgt_epi8 (v, _mm_set1_epi8(31));
return _mm_movemask_epi8 (_mm_andnot_si128 (e2, e1));
}
// ascii: 0x00 ~ 0x7F
static inline int _mm_nonascii_mask(__m128i v) {
return _mm_movemask_epi8(v);
}
static inline ssize_t advance_string_validate(const GoString *src, long p, int64_t *ep) {
char ch;
uint64_t m0, m1, m2;
uint64_t es, fe, os;
uint64_t cr = 0;
long qp = 0;
long np = 0;
/* buffer pointers */
size_t nb = src->len;
const char * sp = src->buf;
const char * ss = src->buf;
/* prevent out-of-bounds accessing */
if (unlikely(nb == p)) {
return -ERR_EOF;
}
#define ep_init() *ep = -1;
#define ep_setc() ep_setx(sp - ss - 1)
#define ep_setx(x) if (*ep == -1) { *ep = (x); }
#define ep_seterr(x) *ep = (x);
/* seek to `p` */
nb -= p;
sp += p;
ep_init()
#if USE_AVX2
/* initialize vectors */
__m256i v0;
__m256i v1;
__m256i cq = _mm256_set1_epi8('"');
__m256i cx = _mm256_set1_epi8('\\');
/* partial masks */
uint32_t s0, s1;
uint32_t t0, t1;
uint32_t c0, c1;
#else
/* initialize vectors */
__m128i v0;
__m128i v1;
__m128i v2;
__m128i v3;
__m128i cq = _mm_set1_epi8('"');
__m128i cx = _mm_set1_epi8('\\');
/* partial masks */
uint32_t s0, s1, s2, s3;
uint32_t t0, t1, t2, t3;
uint32_t c0, c1, c2, c3;
#endif
#define m0_mask(add) \
m1 &= ~cr; \
fe = (m1 << 1) | cr; \
os = (m1 & ~fe) & ODD_MASK; \
es = add(os, m1, &cr) << 1; \
m0 &= ~(fe & (es ^ EVEN_MASK));
/* 64-byte SIMD loop */
while (likely(nb >= 64)) {
#if USE_AVX2
v0 = _mm256_loadu_si256 ((const void *)(sp + 0));
v1 = _mm256_loadu_si256 ((const void *)(sp + 32));
s0 = _mm256_get_mask(v0, cq);
s1 = _mm256_get_mask(v1, cq);
t0 = _mm256_get_mask(v0, cx);
t1 = _mm256_get_mask(v1, cx);
c0 = _mm256_cchars_mask(v0);
c1 = _mm256_cchars_mask(v1);
m0 = ((uint64_t)s1 << 32) | (uint64_t)s0;
m1 = ((uint64_t)t1 << 32) | (uint64_t)t0;
m2 = ((uint64_t)c1 << 32) | (uint64_t)c0;
#else
v0 = _mm_loadu_si128 ((const void *)(sp + 0));
v1 = _mm_loadu_si128 ((const void *)(sp + 16));
v2 = _mm_loadu_si128 ((const void *)(sp + 32));
v3 = _mm_loadu_si128 ((const void *)(sp + 48));
s0 = _mm_get_mask(v0, cq);
s1 = _mm_get_mask(v1, cq);
s2 = _mm_get_mask(v2, cq);
s3 = _mm_get_mask(v3, cq);
t0 = _mm_get_mask(v0, cx);
t1 = _mm_get_mask(v1, cx);
t2 = _mm_get_mask(v2, cx);
t3 = _mm_get_mask(v3, cx);
c0 = _mm_cchars_mask(v0);
c1 = _mm_cchars_mask(v1);
c2 = _mm_cchars_mask(v2);
c3 = _mm_cchars_mask(v3);
m0 = ((uint64_t)s3 << 48) | ((uint64_t)s2 << 32) | ((uint64_t)s1 << 16) | (uint64_t)s0;
m1 = ((uint64_t)t3 << 48) | ((uint64_t)t2 << 32) | ((uint64_t)t1 << 16) | (uint64_t)t0;
m2 = ((uint64_t)c3 << 48) | ((uint64_t)c2 << 32) | ((uint64_t)c1 << 16) | (uint64_t)c0;
#endif
/** update first quote position */
if (unlikely(m1 != 0)) {
ep_setx(sp - ss + __builtin_ctzll(m1))
}
/** mask all the escaped quotes */
if (unlikely(m1 != 0 || cr != 0)) {
m0_mask(add64)
}
qp = m0 ? __builtin_ctzll(m0) : 64;
np = m2 ? __builtin_ctzll(m2) : 64;
/* get the position of end quote */
if (m0 != 0) {
/* check control chars in JSON string */
if (unlikely(np < qp)) {
ep_seterr(sp - ss + np)
return -ERR_INVAL;
}
return sp - ss + qp + 1;
}
/* check control chars in JSON string */
if (unlikely(m2 != 0)) {
ep_setx(sp - ss + np)
return -ERR_INVAL;
}
/* move to the next block */
sp += 64;
nb -= 64;
}
/* 32-byte SIMD round */
if (likely(nb >= 32)) {
#if USE_AVX2
v0 = _mm256_loadu_si256 ((const void *)sp);
s0 = _mm256_get_mask (v0, cq);
t0 = _mm256_get_mask (v0, cx);
c0 = _mm256_cchars_mask(v0);
m0 = (uint64_t)s0;
m1 = (uint64_t)t0;
m2 = (uint64_t)c0;
#else
v0 = _mm_loadu_si128 ((const void *)(sp + 0));
v1 = _mm_loadu_si128 ((const void *)(sp + 16));
s0 = _mm_get_mask(v0, cq);
s1 = _mm_get_mask(v1, cq);
t0 = _mm_get_mask(v0, cx);
t1 = _mm_get_mask(v1, cx);
c0 = _mm_cchars_mask(v0);
c1 = _mm_cchars_mask(v1);
m0 = ((uint64_t)s1 << 16) | (uint64_t)s0;
m1 = ((uint64_t)t1 << 16) | (uint64_t)t0;
m2 = ((uint64_t)c1 << 16) | (uint64_t)c0;
#endif
/** update first quote position */
if (unlikely(m1 != 0)) {
ep_setx(sp - ss + __builtin_ctzll(m1))
}
/** mask all the escaped quotes */
if (unlikely(m1 != 0 || cr != 0)) {
m0_mask(add32)
}
qp = m0 ? __builtin_ctzll(m0) : 64;
np = m2 ? __builtin_ctzll(m2) : 64;
/* get the position of end quote */
if (m0 != 0) {
if (unlikely(np < qp)) {
ep_seterr(sp - ss + np)
return -ERR_INVAL;
}
return sp - ss + qp + 1;
}
/* check control chars in JSON string */
if (unlikely(m2 != 0)) {
ep_seterr(sp - ss + __builtin_ctzll(m2))
return -ERR_INVAL;
}
/* move to the next block */
sp += 32;
nb -= 32;
}
/* check for carry */
if (unlikely(cr != 0)) {
if (nb == 0) {
return -ERR_EOF;
} else {
ep_setc()
sp++, nb--;
}
}
/* handle the remaining bytes with scalar code */
while (nb > 0) {
ch = *sp;
if (ch == '"') {
return sp - ss + 1;
}
/* valid the escaped chars */
if (unlikely(ch == '\\')) {
if (nb == 1) {
return -ERR_EOF;
}
ep_setx(sp - ss)
sp += 2, nb -= 2;
continue;
}
/* valid unescaped chars */
if (unlikely( ch >= 0 && ch <= 0x1f)) { // control chars
ep_seterr(sp - ss)
return -ERR_INVAL;
}
sp++, nb--;
}
return -ERR_EOF;
#undef ep_init
#undef ep_setc
#undef ep_setx
#undef ep_seterr
#undef m0_mask
}
static inline ssize_t advance_string(const GoString *src, long p, int64_t *ep, uint64_t flags) {
if ((flags & MASK_VALIDATE_STRING) != 0) {
return advance_string_validate(src, p, ep);
} else {
return advance_string_default(src, p, ep);
}
}
/** Value Scanning Routines **/
long value(const char *s, size_t n, long p, JsonState *ret, uint64_t flags) {
long q = p;
GoString m = {.buf = s, .len = n};
bool allow_control = (flags & MASK_ALLOW_CONTROL) != 0;
/* parse the next identifier, q is UNSAFE, may cause out-of-bounds accessing */
switch (advance_ns(&m, &q)) {
case '-' : /* fallthrough */
case '0' : /* fallthrough */
case '1' : /* fallthrough */
case '2' : /* fallthrough */
case '3' : /* fallthrough */
case '4' : /* fallthrough */
case '5' : /* fallthrough */
case '6' : /* fallthrough */
case '7' : /* fallthrough */
case '8' : /* fallthrough */
case '9' : vdigits(&m, &q, ret, flags) ; return q;
case '"' : vstring(&m, &q, ret, flags) ; return q;
case 'n' : ret->vt = advance_dword(&m, &q, 1, V_NULL, VS_NULL) ; return q;
case 't' : ret->vt = advance_dword(&m, &q, 1, V_TRUE, VS_TRUE) ; return q;
case 'f' : ret->vt = advance_dword(&m, &q, 0, V_FALSE, VS_ALSE) ; return q;
case '[' : ret->vt = V_ARRAY ; return q;
case '{' : ret->vt = V_OBJECT ; return q;
case ':' : ret->vt = allow_control ? V_KEY_SEP : -ERR_INVAL ; return allow_control ? q : q - 1;
case ',' : ret->vt = allow_control ? V_ELEM_SEP : -ERR_INVAL ; return allow_control ? q : q - 1;
case ']' : ret->vt = allow_control ? V_ARRAY_END : -ERR_INVAL ; return allow_control ? q : q - 1;
case '}' : ret->vt = allow_control ? V_OBJECT_END : -ERR_INVAL ; return allow_control ? q : q - 1;
case 0 : ret->vt = V_EOF ; return q;
default : ret->vt = -ERR_INVAL ; return q - 1;
}
}
void vstring(const GoString *src, long *p, JsonState *ret, uint64_t flags) {
int64_t v = -1;
int64_t i = *p;
ssize_t e = advance_string(src, i, &v, flags);
/* check for errors */
if (e < 0) {
*p = src->len;
ret->vt = e;
return;
}
/* update the result, and fix the escape position (escaping past the end of string) */
*p = e;
ret->iv = i;
ret->vt = V_STRING;
ret->ep = v >= e ? -1 : v;
}
#define set_vt(t) \
ret->vt = t;
#define init_ret(t) \
ret->vt = t; \
ret->dv = 0.0; \
ret->iv = 0; \
ret->ep = *p;
#define check_eof() \
if (i >= n) { \
*p = n; \
ret->vt = -ERR_EOF; \
return; \
}
#define check_sign(on_neg) \
if (s[i] == '-') { \
i++; \
on_neg; \
check_eof() \
}
#define check_digit() \
if (s[i] < '0' || s[i] > '9') { \
*p = i; \
ret->vt = -ERR_INVAL; \
return; \
}
#define check_leading_zero() \
if (s[i] == '0' && (i >= n || (s[i + 1] != '.' && s[i + 1] != 'e' && s[i + 1] != 'E'))) { \
*p = ++i; \
return; \
}
#define parse_sign(sgn) \
if (s[i] == '+' || s[i] == '-') { \
sgn = s[i++] == '+' ? 1 : -1; \
check_eof() \
}
#define is_digit(val) \
'0' <= val && val <= '9'
#define add_integer_to_mantissa(man, man_nd, exp10, dig) \
if (man_nd < 19) { \
man = man * 10 + dig; \
man_nd++; \
} else { \
exp10++; \
}
#define add_float_to_mantissa(man, man_nd, exp10, dig) \
man = man * 10 + dig; \
man_nd++; \
exp10--;
#define parse_float_digits(val, sgn, ...) \
while (i < n && s[i] >= '0' && s[i] <= '9' __VA_ARGS__) { \
val *= 10; \
val += sgn * (s[i++] - '0'); \
}
#define parse_integer_digits(val, sgn, ovf) \
while (i < n && s[i] >= '0' && s[i] <= '9') { \
if (add_digit_overflow(val, sgn * (s[i++] - '0'))) { \
ovf = 1; \
break; \
} \
}
#define add_digit_overflow(val, chr) ( \
__builtin_mul_overflow(val, 10, &val) || \
__builtin_add_overflow(val, chr, &val) \
)
#define vinteger(type, sgn, on_neg) \
int ovf = 0; \
type val = 0; \
\
/* initial buffer pointers */ \
long i = *p; \
size_t n = src->len; \
const char * s = src->buf; \
\
/* initialize the result, and check for '-' */ \
init_ret(V_INTEGER) \
check_eof() \
check_sign(on_neg) \
\
/* check for leading zero or any digits */ \
check_digit() \
check_leading_zero() \
parse_integer_digits(val, sgn, ovf) \
\
/* check for overflow */ \
if (ovf) { \
*p = i - 1; \
ret->vt = -ERR_OVERFLOW; \
return; \
} \
\
/* check for the decimal part */ \
if (i < n && s[i] == '.') { \
*p = i; \
ret->vt = -ERR_NUMBER_FMT; \
return; \
} \
\
/* check for the exponent part */ \
if (i < n && (s[i] == 'e' || s[i] == 'E')) { \
*p = i; \
ret->vt = -ERR_NUMBER_FMT; \
return; \
} \
\
/* update the result */ \
*p = i; \
ret->iv = val;
/** check whether float can represent the val exactly **/
static inline bool is_atof_exact(uint64_t man, int exp, int sgn, double *val) {
*val = (double)man;
if (man >> 52 != 0) {
return false;
}
/* equal to if (sgn == -1) { *val *= -1; } */
*(uint64_t *)val |= ((uint64_t)(sgn) >> 63 << 63);
if (exp == 0 || man == 0) {
return true;
} else if (exp > 0 && exp <= 15+22) {
/* uint64 integers: accurate range <= 10^15 *
* Powers of 10: accurate range <= 10^22, as P10_TAB *
* Example: man 1, exp 36, is ok */
if (exp > 22) {
*val *= P10_TAB[exp-22];
exp = 22;
}
/* f is not accurate when too larger */
if (*val > 1e15 || *val < -1e15) {
return false;
}
*val *= P10_TAB[exp];
return true;
} else if (exp < 0 && exp >= -22) {
*val /= P10_TAB[-exp];
return true;
}
return false;
}
static inline double atof_fast(uint64_t man, int exp, int sgn, int trunc, double *val) {
double val_up = 0.0;
/* look-up for fast atof if the conversion can be exactly */
if (is_atof_exact(man, exp, sgn, val)) {
return true;
}
/* A fast atof algorithm for high percison */
if (atof_eisel_lemire64(man, exp, sgn, val)) {
if (!trunc || (atof_eisel_lemire64(man+1, exp, sgn, &val_up) && val_up == *val)) {
return true;
}
}
return false;
}
static bool inline is_overflow(uint64_t man, int sgn, int exp10) {
/* the former exp10 != 0 means man has overflowed
* the later euqals to man*sgn < INT64_MIN or > INT64_MAX */
return exp10 != 0 ||
((man >> 63) == 1 && ((uint64_t)sgn & man) != (1ull << 63));
}
void vnumber(const GoString *src, long *p, JsonState *ret) {
int sgn = 1;
uint64_t man = 0; // mantissa for double (float64)
int man_nd = 0; // # digits of mantissa, 10 ^ 19 fits uint64_t
int exp10 = 0; // val = sgn * man * 10 ^ exp10
int trunc = 0;
double val = 0;
/* initial buffer pointers */
long i = *p;
size_t n = src->len;
const char * s = src->buf;
char *dbuf = ret->dbuf;
ssize_t dcap = ret->dcap;
/* initialize the result, and check for EOF */
init_ret(V_INTEGER)
check_eof()
check_sign(sgn = -1)
/* check for leading zero */
check_digit()
check_leading_zero()
/* parse the integer part */
while (i < n && is_digit(s[i])) {
add_integer_to_mantissa(man, man_nd, exp10, (s[i] - '0'))
i++;
}
if (exp10 > 0) {
trunc = 1;
}
/* check for decimal points */
if (i < n && s[i] == '.') {
i++;
set_vt(V_DOUBLE)
check_eof()
check_digit()
}
/* skip the leading zeros of 0.000xxxx */
if (man == 0 && exp10 == 0) {
while (i < n && s[i] == '0') {
i++;
exp10--;
}
man = 0;
man_nd = 0;
}
/* the fractional part (uint64_t mantissa can represent at most 19 digits) */
while (i < n && man_nd < 19 && is_digit(s[i])) {
add_float_to_mantissa(man, man_nd, exp10, (s[i] - '0'))
i++;
}
/* skip the remaining digits */
while (i < n && is_digit(s[i])) {
trunc = 1;
i++;
}
/* check for exponent */
if (i < n && (s[i] == 'e' || s[i] == 'E')) {
int esm = 1;
int exp = 0;
/* check for the '+' or '-' sign, and parse the power */
i++;
set_vt(V_DOUBLE)
check_eof()
parse_sign(esm)
check_digit()
while (i < n && is_digit(s[i])) {
if (exp < 10000) {
exp = exp * 10 + (s[i] - '0');
}
i++;
}
exp10 += exp * esm;
goto parse_float;
}
if (ret->vt == V_INTEGER) {
if (!is_overflow(man, sgn, exp10)) {
ret->iv = (int64_t)man * sgn;
/* following lines equal to ret->dv = (double)(man) * sgn */
ret->dv = (double)(man);
*(uint64_t *)&ret->dv |= ((uint64_t)(sgn) >> 63 << 63);
*p = i;
return;
}
set_vt(V_DOUBLE)
}
parse_float:
/* when fast algorithms failed, use slow fallback.*/
if(!atof_fast(man, exp10, sgn, trunc, &val)) {
val = atof_native(s + *p, i - *p, dbuf, dcap);
}
/* check parsed double val */
if (is_infinity(val)) {
ret->vt = -ERR_FLOAT_INF;
}
/* update the result */
ret->dv = val;
*p = i;
}
void vsigned(const GoString *src, long *p, JsonState *ret) {
int64_t sgn = 1;
vinteger(int64_t, sgn, sgn = -1)
}
void vunsigned(const GoString *src, long *p, JsonState *ret) {
vinteger(uint64_t, 1, {
*p = i - 1;
ret->vt = -ERR_NUMBER_FMT;
return;
})
}
#undef init_ret
#undef check_eof
#undef check_digit
#undef check_leading_zero
#undef parse_sign
#undef is_digit
#undef add_integer_to_mantissa
#undef add_float_to_mantissa
#undef parse_float_digits
#undef parse_integer_digits
#undef add_digit_overflow
#undef vinteger
/** Value Skipping FSM **/
#define FSM_VAL 0
#define FSM_ARR 1
#define FSM_OBJ 2
#define FSM_KEY 3
#define FSM_ELEM 4
#define FSM_ARR_0 5
#define FSM_OBJ_0 6
#define FSM_DROP(v) (v)->sp--
#define FSM_REPL(v, t) (v)->vt[(v)->sp - 1] = (t)
#define FSM_CHAR(c) do { if (ch != (c)) return -ERR_INVAL; } while (0)
#define FSM_XERR(v) do { long r = (v); if (r < 0) return r; } while (0)
static inline void fsm_init(StateMachine *self, int vt) {
self->sp = 1;
self->vt[0] = vt;
}
static inline long fsm_push(StateMachine *self, int vt) {
if (self->sp >= MAX_RECURSE) {
return -ERR_RECURSE_MAX;
} else {
self->vt[self->sp++] = vt;
return 0;
}
}
static inline long fsm_exec(StateMachine *self, const GoString *src, long *p, uint64_t flags) {
int vt;
char ch;
long vi = -1;
/* run until no more nested values */
while (self->sp) {
ch = advance_ns(src, p);
if (ch == 0) {
return -ERR_EOF;
}
vt = self->vt[self->sp - 1];
/* set the start address if any */
if (vi == -1) {
vi = *p - 1;
}
/* check for special types */
switch (vt) {
default: {
FSM_DROP(self);
break;
}
/* arrays */
case FSM_ARR: {
switch (ch) {
case ']' : FSM_DROP(self); continue;
case ',' : FSM_XERR(fsm_push(self, FSM_VAL)); continue;
default : return -ERR_INVAL;
}
}
/* objects */
case FSM_OBJ: {
switch (ch) {
case '}' : FSM_DROP(self); continue;
case ',' : FSM_XERR(fsm_push(self, FSM_KEY)); continue;
default : return -ERR_INVAL;
}
}
/* object keys */
case FSM_KEY: {
FSM_CHAR('"');
FSM_REPL(self, FSM_ELEM);
FSM_XERR(skip_string(src, p, flags));
continue;
}
/* object element */
case FSM_ELEM: {
FSM_CHAR(':');
FSM_REPL(self, FSM_VAL);
continue;
}
/* arrays, first element */
case FSM_ARR_0: {
if (ch == ']') {
FSM_DROP(self);
continue;
} else {
FSM_REPL(self, FSM_ARR);
break;
}
}
/* objects, first pair */
case FSM_OBJ_0: {
switch (ch) {
default: {
return -ERR_INVAL;
}
/* empty object */
case '}': {
FSM_DROP(self);
continue;
}
/* the quote of the first key */
case '"': {
FSM_REPL(self, FSM_OBJ);
FSM_XERR(skip_string(src, p, flags));
FSM_XERR(fsm_push(self, FSM_ELEM));
continue;
}
}
}
}
/* simple values */
switch (ch) {
case '0' : /* fallthrough */
case '1' : /* fallthrough */
case '2' : /* fallthrough */
case '3' : /* fallthrough */
case '4' : /* fallthrough */
case '5' : /* fallthrough */
case '6' : /* fallthrough */
case '7' : /* fallthrough */
case '8' : /* fallthrough */
case '9' : FSM_XERR(skip_positive(src, p)); break;
case '-' : FSM_XERR(skip_negative(src, p)); break;
case 'n' : FSM_XERR(advance_dword(src, p, 1, *p - 1, VS_NULL)); break;
case 't' : FSM_XERR(advance_dword(src, p, 1, *p - 1, VS_TRUE)); break;
case 'f' : FSM_XERR(advance_dword(src, p, 0, *p - 1, VS_ALSE)); break;
case '[' : FSM_XERR(fsm_push(self, FSM_ARR_0)); break;
case '{' : FSM_XERR(fsm_push(self, FSM_OBJ_0)); break;
case '"' : FSM_XERR(skip_string(src, p, flags)); break;
case 0 : return -ERR_EOF;
default : return -ERR_INVAL;
}
}
/* all done */
return vi;
}
#undef FSM_DROP
#undef FSM_REPL
#undef FSM_CHAR
#undef FSM_XERR
#define check_bits(mv) \
if (unlikely((v = mv & (mv - 1)) != 0)) { \
return -(sp - ss + __builtin_ctz(v) + 1); \
}
#define check_sidx(iv) \
if (likely(iv == -1)) { \
iv = sp - ss - 1; \
} else { \
return -(sp - ss); \
}
#define check_vidx(iv, mv) \
if (mv != 0) { \
if (likely(iv == -1)) { \
iv = sp - ss + __builtin_ctz(mv); \
} else { \
return -(sp - ss + __builtin_ctz(mv) + 1); \
} \
}
static inline long do_skip_number(const char *sp, size_t nb) {
long di = -1;
long ei = -1;
long si = -1;
const char * ss = sp;
/* check for EOF */
if (nb == 0) {
return -1;
}
/* special case of '0' */
if (*sp == '0' && (nb == 1 || (sp[1] != '.' && sp[1] != 'e' && sp[1] != 'E'))) {
return 1;
}
#if USE_AVX2
/* can do with AVX-2 */
if (likely(nb >= 32)) {
__m256i d9 = _mm256_set1_epi8('9');
__m256i ds = _mm256_set1_epi8('/');
__m256i dp = _mm256_set1_epi8('.');
__m256i el = _mm256_set1_epi8('e');
__m256i eu = _mm256_set1_epi8('E');
__m256i xp = _mm256_set1_epi8('+');
__m256i xm = _mm256_set1_epi8('-');
/* 32-byte loop */
do {
__m256i sb = _mm256_loadu_si256 ((const void *)sp);
__m256i i0 = _mm256_cmpgt_epi8 (sb, ds);
__m256i i9 = _mm256_cmpgt_epi8 (sb, d9);
__m256i id = _mm256_cmpeq_epi8 (sb, dp);
__m256i il = _mm256_cmpeq_epi8 (sb, el);
__m256i iu = _mm256_cmpeq_epi8 (sb, eu);
__m256i ip = _mm256_cmpeq_epi8 (sb, xp);
__m256i im = _mm256_cmpeq_epi8 (sb, xm);
__m256i iv = _mm256_andnot_si256 (i9, i0);
__m256i ie = _mm256_or_si256 (il, iu);
__m256i is = _mm256_or_si256 (ip, im);
__m256i rt = _mm256_or_si256 (iv, id);
__m256i ru = _mm256_or_si256 (ie, is);
__m256i rv = _mm256_or_si256 (rt, ru);
/* exponent and sign position */
uint32_t md = _mm256_movemask_epi8(id);
uint32_t me = _mm256_movemask_epi8(ie);
uint32_t ms = _mm256_movemask_epi8(is);
uint32_t mr = _mm256_movemask_epi8(rv);
/* mismatch position */
uint32_t v;
uint32_t i = __builtin_ctzll(~(uint64_t)mr | 0x0100000000);
/* mask out excess characters */
if (i != 32) {
md &= (1 << i) - 1;
me &= (1 << i) - 1;
ms &= (1 << i) - 1;
}
/* check & update decimal point, exponent and sign index */
check_bits(md)
check_bits(me)
check_bits(ms)
check_vidx(di, md)
check_vidx(ei, me)
check_vidx(si, ms)
/* check for valid number */
if (i != 32) {
sp += i;
_mm256_zeroupper();
goto check_index;
}
/* move to next block */
sp += 32;
nb -= 32;
} while (nb >= 32);
/* clear the upper half to prevent AVX-SSE transition penalty */
_mm256_zeroupper();
}
#endif
/* can do with SSE */
if (likely(nb >= 16)) {
__m128i dc = _mm_set1_epi8(':');
__m128i ds = _mm_set1_epi8('/');
__m128i dp = _mm_set1_epi8('.');
__m128i el = _mm_set1_epi8('e');
__m128i eu = _mm_set1_epi8('E');
__m128i xp = _mm_set1_epi8('+');
__m128i xm = _mm_set1_epi8('-');
/* 16-byte loop */
do {
__m128i sb = _mm_loadu_si128 ((const void *)sp);
__m128i i0 = _mm_cmpgt_epi8 (sb, ds);
__m128i i9 = _mm_cmplt_epi8 (sb, dc);
__m128i id = _mm_cmpeq_epi8 (sb, dp);
__m128i il = _mm_cmpeq_epi8 (sb, el);
__m128i iu = _mm_cmpeq_epi8 (sb, eu);
__m128i ip = _mm_cmpeq_epi8 (sb, xp);
__m128i im = _mm_cmpeq_epi8 (sb, xm);
__m128i iv = _mm_and_si128 (i9, i0);
__m128i ie = _mm_or_si128 (il, iu);
__m128i is = _mm_or_si128 (ip, im);
__m128i rt = _mm_or_si128 (iv, id);
__m128i ru = _mm_or_si128 (ie, is);
__m128i rv = _mm_or_si128 (rt, ru);
/* exponent and sign position */
uint32_t md = _mm_movemask_epi8(id);
uint32_t me = _mm_movemask_epi8(ie);
uint32_t ms = _mm_movemask_epi8(is);
uint32_t mr = _mm_movemask_epi8(rv);
/* mismatch position */
uint32_t v;
uint32_t i = __builtin_ctzll(~mr | 0x00010000);
/* mask out excess characters */
if (i != 16) {
md &= (1 << i) - 1;
me &= (1 << i) - 1;
ms &= (1 << i) - 1;
}
/* check & update exponent and sign index */
check_bits(md)
check_bits(me)
check_bits(ms)
check_vidx(di, md)
check_vidx(ei, me)
check_vidx(si, ms)
/* check for valid number */
if (i != 16) {
sp += i;
goto check_index;
}
/* move to next block */
sp += 16;
nb -= 16;
} while (nb >= 16);
}
/* remaining bytes, do with scalar code */
while (likely(nb-- > 0)) {
switch (*sp++) {
case '0' : /* fallthrough */
case '1' : /* fallthrough */
case '2' : /* fallthrough */
case '3' : /* fallthrough */
case '4' : /* fallthrough */
case '5' : /* fallthrough */
case '6' : /* fallthrough */
case '7' : /* fallthrough */
case '8' : /* fallthrough */
case '9' : break;
case '.' : check_sidx(di); break;
case 'e' : /* fallthrough */
case 'E' : check_sidx(ei); break;
case '+' : /* fallthrough */
case '-' : check_sidx(si); break;
default : sp--; goto check_index;
}
}
check_index:
if (di == 0 || si == 0 || ei == 0) {
return -1;
} else if (di == sp - ss - 1|| si == sp - ss - 1 || ei == sp - ss - 1) {
return -(sp - ss);
} else if (si > 0 && ei != si - 1) {
return -si - 1;
} else if (di >= 0 && ei >= 0 && di > ei - 1) {
return -di - 1;
} else if (di >= 0 && ei >= 0 && di == ei - 1) {
return -ei - 1;
} else {
return sp - ss;
}
}
#undef check_bits
#undef check_sidx
#undef check_vidx
long skip_array(const GoString *src, long *p, StateMachine *m, uint64_t flags) {
fsm_init(m, FSM_ARR_0);
return fsm_exec(m, src, p, flags);
}
long skip_object(const GoString *src, long *p, StateMachine *m, uint64_t flags) {
fsm_init(m, FSM_OBJ_0);
return fsm_exec(m, src, p, flags);
}
long skip_string(const GoString *src, long *p, uint64_t flags) {
int64_t v = -1;
ssize_t q = *p - 1; // start position
ssize_t e = advance_string(src, *p, &v, flags);
/* check for errors */
if (e < 0) {
*p = e == -ERR_EOF ? src->len : v;
return e;
}
/* update the position */
*p = e;
return q;
}
long skip_negative(const GoString *src, long *p) {
long i = *p;
long r = do_skip_number(src->buf + i, src->len - i);
/* check for errors */
if (r < 0) {
*p -= r + 1;
return -ERR_INVAL;
}
/* update value pointer */
*p += r;
return i - 1;
}
long skip_positive(const GoString *src, long *p) {
long i = *p - 1;
long r = do_skip_number(src->buf + i, src->len - i);
/* check for errors */
if (r < 0) {
*p -= r + 2;
return -ERR_INVAL;
}
/* update value pointer */
*p += r - 1;
return i;
}
long skip_number(const GoString *src, long *p) {
const char* ss = src->buf;
const char* sp = src->buf + *p;
size_t nb = src->len;
long i = *p;
long r;
bool neg = *sp == '-';
sp += neg;
nb -= neg;
if (unlikely(nb <= 0)) {
*p = sp - ss;
return -ERR_EOF;
}
if (unlikely(i < nb && (*sp > '9' || *sp < '0'))) {
*p = sp - ss;
return -ERR_INVAL;
}
r = do_skip_number(sp, nb);
if (unlikely(r < 0)) {
*p = sp - (r + 1) - ss;
return -ERR_INVAL;
}
*p = sp + r - ss;
return i;
}
long skip_one(const GoString *src, long *p, StateMachine *m, uint64_t flags) {
fsm_init(m, FSM_VAL);
return fsm_exec(m, src, p, flags);
}
long validate_one(const GoString *src, long *p, StateMachine *m) {
fsm_init(m, FSM_VAL);
return fsm_exec(m, src, p, MASK_VALIDATE_STRING);
}
/* Faster skip api for sonic.ast */
static always_inline uint64_t get_maskx64(const char *s, char c) {
#if USE_AVX2
__m256i v0 = _mm256_loadu_si256((__m256i const *)s);
__m256i v1 = _mm256_loadu_si256((__m256i const *)(s + 32));
uint32_t m0 = _mm256_movemask_epi8(_mm256_cmpeq_epi8(v0, _mm256_set1_epi8(c)));
uint32_t m1 = _mm256_movemask_epi8(_mm256_cmpeq_epi8(v1, _mm256_set1_epi8(c)));
return ((uint64_t)(m1) << 32) | (uint64_t)(m0);
#else
__m128i v0 = _mm_loadu_si128((__m128i const*)s);
__m128i v1 = _mm_loadu_si128((__m128i const*)(s + 16));
__m128i v2 = _mm_loadu_si128((__m128i const*)(s + 32));
__m128i v3 = _mm_loadu_si128((__m128i const*)(s + 48));
uint32_t m0 = _mm_movemask_epi8(_mm_cmpeq_epi8(v0, _mm_set1_epi8(c)));
uint32_t m1 = _mm_movemask_epi8(_mm_cmpeq_epi8(v1, _mm_set1_epi8(c)));
uint32_t m2 = _mm_movemask_epi8(_mm_cmpeq_epi8(v2, _mm_set1_epi8(c)));
uint32_t m3 = _mm_movemask_epi8(_mm_cmpeq_epi8(v3, _mm_set1_epi8(c)));
return ((uint64_t)(m3) << 48) | ((uint64_t)(m2) << 32) | ((uint64_t)(m1) << 16) | (uint64_t)(m0);
#endif
}
static always_inline uint64_t get_maskx32(const char *s, char c) {
#if USE_AVX2
__m256i v0 = _mm256_loadu_si256((__m256i const *)s);
uint64_t m0 = (unsigned)_mm256_movemask_epi8(_mm256_cmpeq_epi8(v0, _mm256_set1_epi8(c)));
return m0;
#else
__m128i v0 = _mm_loadu_si128((__m128i const*)s);
__m128i v1 = _mm_loadu_si128((__m128i const*)(s + 16));
uint64_t m0 = (unsigned)_mm_movemask_epi8(_mm_cmpeq_epi8(v0, _mm_set1_epi8(c)));
uint64_t m1 = (unsigned)_mm_movemask_epi8(_mm_cmpeq_epi8(v1, _mm_set1_epi8(c)));
return m0 | (m1 << 16);
#endif
}
// get the string (besides in quote) mask
static always_inline uint64_t get_string_maskx64(const char *s, uint64_t *prev_inquote, uint64_t *prev_bs) {
uint64_t escaped = *prev_bs;
uint64_t quote_mask = 0, bs_mask = 0;
/* read and get the quote or backslash bitmask */
quote_mask = get_maskx64(s, '"');
bs_mask = get_maskx64(s, '\\');
/* get the escaped bitmask */
if (bs_mask || *prev_bs) {
bs_mask &= ~(*prev_bs);
uint64_t follow_bs = (bs_mask << 1) | *prev_bs;
uint64_t bs_start = bs_mask & ~follow_bs;
uint64_t odd_start = bs_start & ODD_MASK;
uint64_t even_or_oc = add64(odd_start, bs_mask, prev_bs);
uint64_t even_or_escaped = (even_or_oc << 1) ^ EVEN_MASK;
escaped = follow_bs & even_or_escaped;
} else {
*prev_bs = 0;
}
quote_mask &= ~escaped;
/* get the inquote bitmask */
uint64_t inquote = _mm_cvtsi128_si64(_mm_clmulepi64_si128(_mm_set_epi64x(0, quote_mask), _mm_set1_epi8('\xFF'), 0));
inquote ^= *prev_inquote;
*prev_inquote = (uint64_t)(((int64_t)(inquote)) >> 63);
return inquote;
}
// get the next json structural, '}', ']' or ','。
#if USE_AVX2
static always_inline int get_structural_maskx32(const char *s) {
__m256i v = _mm256_loadu_si256((const void *)s);
__m256i e1 = _mm256_cmpeq_epi8(v, _mm256_set1_epi8('}'));
__m256i e2 = _mm256_cmpeq_epi8(v, _mm256_set1_epi8(']'));
__m256i e3 = _mm256_cmpeq_epi8(v, _mm256_set1_epi8(','));
__m256i sv = _mm256_or_si256(_mm256_or_si256(e1, e2), e3);
return _mm256_movemask_epi8(sv);
}
#endif
static always_inline int get_structural_maskx16(const char *s) {
__m128i v = _mm_loadu_si128((const void *)s);
__m128i e1 = _mm_cmpeq_epi8(v, _mm_set1_epi8('}'));
__m128i e2 = _mm_cmpeq_epi8(v, _mm_set1_epi8(']'));
__m128i e3 = _mm_cmpeq_epi8(v, _mm_set1_epi8(','));
__m128i sv = _mm_or_si128(_mm_or_si128(e1, e2), e3);
return _mm_movemask_epi8(sv);
}
// skip the number at the next '}', ']' or ',' or the ending of json.
static always_inline long skip_number_fast(const GoString *src, long *p) {
size_t nb = src->len - *p;
const char *s = src->buf + *p;
long vi = *p - 1;
int m = 0;
#if USE_AVX2
while (likely(nb >= 32)) {
if ((m = get_structural_maskx32(s))) {
*p = s - src->buf + __builtin_ctzll(m);
return vi;
}
s += 32, nb -= 32;
}
#endif
while (likely(nb >= 16)) {
if ((m = get_structural_maskx16(s))) {
*p = s - src->buf + __builtin_ctzll(m);
return vi;
}
s += 16, nb -= 16;
}
while (likely(nb > 0)) {
if (*s == '}' || *s == ']' || *s == ',') {
*p = s - src->buf;
return vi;
}
s++, nb--;
}
*p = s - src->buf;
return vi;
}
static always_inline long skip_container_fast(const GoString *src, long *p, char lc, char rc) {
long nb = src->len - *p;
const char *s = src->buf + *p;
long vi = *p - 1;
uint64_t prev_inquote = 0, prev_bs = 0;
uint64_t lbrace = 0, rbrace = 0;
size_t lnum = 0, rnum = 0, last_lnum = 0;
uint64_t inquote = 0;
while (likely(nb >= 64)) {
skip:
inquote = get_string_maskx64(s, &prev_inquote, &prev_bs);
lbrace = get_maskx64(s, lc) & ~inquote;
rbrace = get_maskx64(s, rc) & ~inquote;
/* traverse each right brace */
last_lnum = lnum;
while (rbrace > 0) {
uint64_t lbrace_first = (rbrace - 1) & lbrace;
lnum = last_lnum + __builtin_popcountll((int64_t)lbrace_first);
bool is_closed = lnum <= rnum;
if (is_closed) {
*p = src->len - nb + __builtin_ctzll(rbrace) + 1;
// *p is out-of-bound access here
if (*p > src->len) {
*p = src->len;
return -ERR_EOF;
}
return vi;
}
rbrace &= (rbrace - 1); // clear the lowest right brace
rnum ++;
}
lnum = last_lnum + __builtin_popcountll((int64_t)lbrace);
s += 64, nb -= 64;
}
if (nb <= 0) {
*p = src->len;
return -ERR_EOF;
}
char tbuf[64] = {0};
bool cross_page = vec_cross_page(s, 64);
if (cross_page) {
memcpy_p64(tbuf, s, nb);
s = tbuf;
}
goto skip;
}
static always_inline long skip_object_fast(const GoString *src, long *p) {
return skip_container_fast(src, p, '{', '}');
}
static always_inline long skip_array_fast(const GoString *src, long *p) {
return skip_container_fast(src, p, '[', ']');
}
static always_inline long skip_string_fast(const GoString *src, long *p) {
const char* s = src->buf + *p;
long nb = src->len - *p;
long vi = *p - 1;
uint64_t prev_bs = 0, escaped;
while (likely(nb >= 32)) {
uint32_t quote = get_maskx32(s, '"');
uint32_t bs_mask = get_maskx32(s, '\\');
if (bs_mask || prev_bs) {
bs_mask &= ~prev_bs;
uint64_t follow_bs = (bs_mask << 1) | prev_bs;
uint64_t bs_start = bs_mask & ~follow_bs;
uint64_t odd_start = bs_start & ODD_MASK;
uint64_t even_or_oc = add32(odd_start, bs_mask, &prev_bs);
uint64_t even_or_escaped = (even_or_oc << 1) ^ EVEN_MASK;
escaped = follow_bs & even_or_escaped;
quote &= ~escaped;
}
if (quote) {
*p = s + __builtin_ctzll(quote) + 1 - src->buf;
return vi;
}
s += 32;
nb -= 32;
}
if (unlikely(prev_bs != 0)) {
if (nb == 0) return -ERR_EOF;
s++, nb--;
}
while (likely(nb > 0)) {
if (*s == '\\') {
s += 2, nb -= 2;
continue;
}
if (*s == '"') {
*p = s - src->buf + 1;
return vi;
}
s++, nb--;
}
return -ERR_EOF;
}
long skip_one_fast(const GoString *src, long *p) {
char c = advance_ns(src, p);
/* set the start address */
long vi = *p - 1;
switch (c) {
case '[': return skip_array_fast(src, p);
case '{': return skip_object_fast(src, p);
case '"': return skip_string_fast(src, p);
case '-': case '0' ... '9': return skip_number_fast(src, p);
case 't': case 'n': { if (*p + 3 <= src->len) { *p += 3; } else { return -ERR_EOF; } }; break;
case 'f': { if (*p + 4 <= src->len) { *p += 4; } else { return -ERR_EOF; } }; break;
case 0 : return -ERR_EOF;
default : *p -= 1; return -ERR_INVAL; // backward error position
}
return vi;
}
static always_inline GoKind kind(const GoIface* iface) {
return (iface->type->kind_flags) & GO_KIND_MASK;
}
static always_inline bool is_int(const GoIface* iface) {
return iface->type != NULL && kind(iface) == Int;
}
static always_inline bool is_str(const GoIface* iface) {
return iface->type != NULL && kind(iface) == String;
}
static always_inline GoString get_str(const GoIface* iface) {
return *(GoString*)(iface->value);
}
static always_inline int64_t get_int(const GoIface* iface) {
return *(int64_t*)(iface->value);
}
// xmemcmpeq return true if s1 and s2 is equal for the n bytes, otherwise, return false.
static always_inline bool xmemcmpeq(const char * s1, const char * s2, size_t n) {
bool c1, c2;
#if USE_AVX2
while (n >= 32) {
__m256i v1 = _mm256_loadu_si256((const void *)s1);
__m256i v2 = _mm256_loadu_si256((const void *)s2);
uint32_t mask = ~((uint32_t)_mm256_movemask_epi8(_mm256_cmpeq_epi8(v1, v2)));
if (mask) return false;
s1 += 32;
s2 += 32;
n -= 32;
};
c1 = vec_cross_page(s1, 32);
c2 = vec_cross_page(s2, 32);
// not cross page
if (!c1 && !c2) {
__m256i v1 = _mm256_loadu_si256((const void *)s1);
__m256i v2 = _mm256_loadu_si256((const void *)s2);
uint32_t mask = ~((uint32_t)_mm256_movemask_epi8(_mm256_cmpeq_epi8(v1, v2)));
bool eq = (mask == 0) || (__builtin_ctzll(mask) >= n);
return eq;
}
#endif
while (n >= 16) {
__m128i v1 = _mm_loadu_si128((const void *)s1);
__m128i v2 = _mm_loadu_si128((const void *)s2);
uint16_t mask = ~((uint16_t)_mm_movemask_epi8(_mm_cmpeq_epi8(v1, v2)));
if (mask != 0) return false;
s1 += 16;
s2 += 16;
n -= 16;
};
c1 = vec_cross_page(s1, 16);
c2 = vec_cross_page(s2, 16);
// not cross page
if (!c1 && !c2) {
__m128i v1 = _mm_loadu_si128((const void *)s1);
__m128i v2 = _mm_loadu_si128((const void *)s2);
uint16_t mask = ~((uint16_t)_mm_movemask_epi8(_mm_cmpeq_epi8(v1, v2)));
bool eq = (mask == 0) || (__builtin_ctzll(mask) >= n);
return eq;
}
// cross page
while (n > 0 && *s1++ == *s2++) n--;
return n == 0;
}
// match_key return negative if errors, zero if not matched, one if matched.
static always_inline long match_key(const GoString *src, long *p, const GoString key) {
static const long not_match = 0;
int64_t v = -1;
long si = *p;
long se = advance_string_default(src, *p, &v);
if (unlikely(se < 0)) {
*p = src->len;
return -ERR_EOF;
}
/* update position */
*p = se;
/* compare non-escaped strings */
if (likely(v == -1 || v > se)) {
long sn = se - si - 1;
// check empty keys
if (!sn && !key.len) {
return true;
}
return sn == key.len && xmemcmpeq(src->buf + si, key.buf, key.len);
}
/* deal with escaped strings */
char buf[8] = {0}; // escaped buffer
const char* sp = src->buf + si;
const char* end = src->buf + se - 1;
const char* kp = key.buf;
const char* ke = key.buf + key.len;
while (sp < end && kp < ke) {
if (*sp == '\\') {
long en = unescape(&sp, end, buf);
if (en < 0) {
*p = sp - src->buf;
return en;
}
const char* ee = buf + en;
const char* ep = buf;
while (kp < ke && ep < ee && *kp == *ep) kp++, ep++;
if (ep != ee) {
return not_match;
}
} else if (*sp == *kp) {
sp++, kp++;
} else {
return not_match;
}
};
return sp == end && kp == ke;
}
long get_by_path(const GoString *src, long *p, const GoSlice *path, StateMachine* sm) {
GoIface *ps = (GoIface*)(path->buf);
GoIface *pe = (GoIface*)(path->buf) + path->len;
char c = 0;
int64_t index;
long found;
query:
/* to be safer for invalid json, use slower skip for the demanded fields */
if (ps == pe) {
return skip_one(src, p, sm, 0);
}
/* match type: should query key in object, query index in array */
c = advance_ns(src, p);
if (is_str(ps)) {
if (c != '{') {
goto err_inval;
}
goto skip_in_obj;
} else if (is_int(ps)) {
if (c != '[') {
goto err_inval;
}
index = get_int(ps);
if (index < 0) {
goto err_path;
}
goto skip_in_arr;
} else {
goto err_path;
}
skip_in_obj:
c = advance_ns(src, p);
if (c == '}') {
goto not_found;
}
if (c != '"') {
goto err_inval;
}
/* parse the object key */
found = match_key(src, p, get_str(ps));
if (found < 0) {
return found; // parse string errors
}
/* value should after : */
c = advance_ns(src, p);
if (c != ':') {
goto err_inval;
}
if (found) {
ps++;
goto query;
}
/* skip the unknown fields */
skip_one_fast(src, p);
c = advance_ns(src, p);
if (c == '}') {
goto not_found;
}
if (c != ',') {
goto err_inval;
}
goto skip_in_obj;
skip_in_arr:
/* check empty array */
c = advance_ns(src, p);
if (c == ']') {
goto not_found;
}
*p -= 1;
/* skip array elem one by one */
while (index-- > 0) {
skip_one_fast(src, p);
c = advance_ns(src, p);
if (c == ']') {
goto not_found;
}
if (c != ',') {
goto err_inval;
}
}
ps++;
goto query;
not_found:
*p -= 1; // backward error position
return -ERR_NOT_FOUND;
err_inval:
*p -= 1;
return -ERR_INVAL;
err_path:
*p -= 1;
return -ERR_UNSUPPORT_TYPE;
}
//
long validate_utf8(const GoString *src, long *p, StateMachine *m) {
xassert(*p >= 0 && src->len > *p);
return validate_utf8_with_errors(src->buf, src->len, p, m);
}
// validate_utf8_fast returns zero if valid, otherwise, the error position.
long validate_utf8_fast(const GoString *s) {
#if USE_AVX2
/* fast path for valid utf8 */
if (validate_utf8_avx2(s) == 0) {
return 0;
}
#endif
return validate_utf8_errors(s);
}