5784751762

Committed 07 Aug 2023 11:54AM UTC coverage: 84.282% (-3.1%) from 87.373%

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ligurio

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setup-gcovr [TO SQUASH]

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97.61

/src/lj_str.c

/*
** String handling.
** Copyright (C) 2005-2017 Mike Pall. See Copyright Notice in luajit.h
*/

#define lj_str_c
#define LUA_CORE

#include "lj_obj.h"
#include "lj_gc.h"
#include "lj_err.h"
#include "lj_str.h"
#include "lj_char.h"

#if LUAJIT_USE_ASAN
/* These functions may read past a buffer end, that's ok. */
GCstr *lj_str_new(lua_State *L, const char *str, size_t lenx)
  __attribute__((no_sanitize_address));

int32_t LJ_FASTCALL lj_str_cmp(GCstr *a, GCstr *b)
  __attribute__((no_sanitize_address));

static LJ_AINLINE int str_fastcmp(const char *a, const char *b, MSize len)
  __attribute__((no_sanitize_address));
#endif

/* -- String helpers ------------------------------------------------------ */

/* Ordered compare of strings. Assumes string data is 4-byte aligned. */
int32_t LJ_FASTCALL lj_str_cmp(GCstr *a, GCstr *b)
{
  MSize i, n = a->len > b->len ? b->len : a->len;
  for (i = 0; i < n; i += 4) {
    /* Note: innocuous access up to end of string + 3. */
    uint32_t va = *(const uint32_t *)(strdata(a)+i);
    uint32_t vb = *(const uint32_t *)(strdata(b)+i);
    if (va != vb) {
#if LJ_LE
      va = lj_bswap(va); vb = lj_bswap(vb);
#endif
      i -= n;
      if ((int32_t)i >= -3) {
        va >>= 32+(i<<3); vb >>= 32+(i<<3);
        if (va == vb) break;
      }
      return va < vb ? -1 : 1;
    }
  }
  return (int32_t)(a->len - b->len);
}

/* Fast string data comparison. Caveat: unaligned access to 1st string! */
static LJ_AINLINE int str_fastcmp(const char *a, const char *b, MSize len)
{
  MSize i = 0;
  lua_assert(len > 0);
  lua_assert((((uintptr_t)a+len-1) & (LJ_PAGESIZE-1)) <= LJ_PAGESIZE-4);
  do {  /* Note: innocuous access up to end of string + 3. */
    uint32_t v = lj_getu32(a+i) ^ *(const uint32_t *)(b+i);
    if (v) {
      i -= len;
#if LJ_LE
      return (int32_t)i >= -3 ? (v << (32+(i<<3))) : 1;
#else
      return (int32_t)i >= -3 ? (v >> (32+(i<<3))) : 1;
#endif
    }
    i += 4;
  } while (i < len);
  return 0;
}

/* Find fixed string p inside string s. */
const char *lj_str_find(const char *s, const char *p, MSize slen, MSize plen)
{
  if (plen <= slen) {
    if (plen == 0) {
      return s;
    } else {
      int c = *(const uint8_t *)p++;
      plen--; slen -= plen;
      while (slen) {
        const char *q = (const char *)memchr(s, c, slen);
        if (!q) break;
        if (memcmp(q+1, p, plen) == 0) return q;
        q++; slen -= (MSize)(q-s); s = q;
      }
    }
  }
  return NULL;
}

/* Check whether a string has a pattern matching character. */
int lj_str_haspattern(GCstr *s)
{
  const char *p = strdata(s), *q = p + s->len;
  while (p < q) {
    int c = *(const uint8_t *)p++;
    if (lj_char_ispunct(c) && strchr("^$*+?.([%-", c))
      return 1;  /* Found a pattern matching char. */
  }
  return 0;  /* No pattern matching chars found. */
}

/* -- String interning ---------------------------------------------------- */

/* Resize the string hash table (grow and shrink). */
void lj_str_resize(lua_State *L, MSize newmask)
{
  global_State *g = G(L);
  GCRef *newhash;
  MSize i;
  if (g->gc.state == GCSsweepstring || newmask >= LJ_MAX_STRTAB-1)
    return;  /* No resizing during GC traversal or if already too big. */
  newhash = lj_mem_newvec(L, newmask+1, GCRef);
  memset(newhash, 0, (newmask+1)*sizeof(GCRef));
  for (i = g->strmask; i != ~(MSize)0; i--) {  /* Rehash old table. */
    GCobj *p = gcref(g->strhash[i]);
    while (p) {  /* Follow each hash chain and reinsert all strings. */
      MSize h = gco2str(p)->hash & newmask;
      GCobj *next = gcnext(p);
      /* NOBARRIER: The string table is a GC root. */
      setgcrefr(p->gch.nextgc, newhash[h]);
      setgcref(newhash[h], p);
      p = next;
    }
  }
  lj_mem_freevec(g, g->strhash, g->strmask+1, GCRef);
  g->strmask = newmask;
  g->strhash = newhash;
}

#if LUAJIT_SMART_STRINGS
static LJ_AINLINE uint32_t
lj_fullhash(const uint8_t *v, MSize len)
{
  MSize a = 0, b = 0;
  MSize c = 0xcafedead;
  MSize d = 0xdeadbeef;
  MSize h = len;
  lua_assert(len >= 12);
  for(; len>8; len-=8, v+=8) {
    a ^= lj_getu32(v);
    b ^= lj_getu32(v+4);
    c += a;
    d += b;
    a = lj_rol(a, 5) - d;
    b = lj_rol(b, 7) - c;
    c = lj_rol(c, 24) ^ a;
    d = lj_rol(d, 1) ^ b;
  }
  a ^= lj_getu32(v+len-8);
  b ^= lj_getu32(v+len-4);
  c += b; c -= lj_rol(a, 9);
  d += a; d -= lj_rol(b, 18);
  h -= lj_rol(a^b,7);
  h += c; h += lj_rol(d,13);
  d ^= c;  d -= lj_rol(c,25);
  h ^= d; h -= lj_rol(d,16);
  c ^= h; c -= lj_rol(h,4);
  d ^= c;  d -= lj_rol(c,14);
  h ^= d; h -= lj_rol(d,24);
  return h;
}
#endif

/* Intern a string and return string object. */
GCstr *lj_str_new(lua_State *L, const char *str, size_t lenx)
{
  global_State *g;
  GCstr *s;
  GCobj *o;
  MSize len = (MSize)lenx;
  uint8_t strflags = 0;
#if LUAJIT_SMART_STRINGS
  unsigned collisions = 0;
#endif
  if (lenx >= LJ_MAX_STR)
    lj_err_msg(L, LJ_ERR_STROV);
  g = G(L);
  if (len == 0)
    return &g->strempty;
  /* Compute string hash. Constants taken from lookup3 hash by Bob Jenkins. */
  MSize h = lua_hash(str, len);
  /* Check if the string has already been interned. */
  o = gcref(g->strhash[h & g->strmask]);
#if LUAJIT_SMART_STRINGS
/*
** The default "fast" string hash function samples only a few positions
** in a string, the remaining bytes don't affect the function's result.
** The function performs well for short strings; however long strings
** can yield extremely high collision rates.
**
** An adaptive schema was implemented. Two hash functions are used
** simultaneously. A bucket is picked based on the output of the fast
** hash function. If an item is to be inserted in a collision chain
** longer than a certain threshold, another bucket is picked based on
** the stronger hash function. Since two hash functions are used
** simultaneously, insert should consider two buckets. The second bucket
** is often NOT considered thanks to the bloom filter. The filter is
** rebuilt during GC cycle.
**
** Parameters below were tuned on a set of benchmarks. Max_collisions is
** also backed by theory: the expected maximum length of a collision
** chain in a hash table with the fill factor of 1.0 is
** O(log(N)/log(log(N))), assuming uniformly distributed random keys.
** The upper bound for N=65,000 is 10, hence 40 is a clear indication of
** an anomaly.
**/
#define max_collisions 40
#define inc_collision_soft() (collisions++)
/* If different strings yield the same hash sum, grow counter faster. */
#define inc_collision_hard() (collisions+=1+(len>>4), 1)
#else
#define inc_collision_hard() (1)
#define inc_collision_soft()
#endif
  if (LJ_LIKELY((((uintptr_t)str+len-1) & (LJ_PAGESIZE-1)) <= LJ_PAGESIZE-4)) {
    while (o != NULL) {
      GCstr *sx = gco2str(o);
      if (sx->hash == h && sx->len == len && inc_collision_hard() &&
                      str_fastcmp(str, strdata(sx), len) == 0) {
        /* Resurrect if dead. Can only happen with fixstring() (keywords). */
        if (isdead(g, o)) flipwhite(o);
        g->strhash_hit++;
        return sx;  /* Return existing string. */
      }
      o = gcnext(o);
      inc_collision_soft();
    }
  } else {  /* Slow path: end of string is too close to a page boundary. */
    while (o != NULL) {
      GCstr *sx = gco2str(o);
      if (sx->hash == h && sx->len == len && inc_collision_hard() &&
                      memcmp(str, strdata(sx), len) == 0) {
        /* Resurrect if dead. Can only happen with fixstring() (keywords). */
        if (isdead(g, o)) flipwhite(o);
        g->strhash_hit++;
        return sx;  /* Return existing string. */
      }
      o = gcnext(o);
      inc_collision_soft();
    }
  }
#if LUAJIT_SMART_STRINGS
  /* "Fast" hash function consumes all bytes of a string <= 12 bytes. */
  if (len > 12) {
    /*
    ** The bloom filter is keyed with the high 12 bits of the fast
    ** hash sum. The filter is rebuilt during GC cycle. It's beneficial
    ** to have these bits readily available and avoid hash sum
    ** recalculation during GC. High 6 bits are included in the "full"
    ** hash sum, and bits 19-25 are stored in s->strflags.
    **/
    int search_fullh =
       bloomtest(g->strbloom.cur[0], h>>(sizeof(h)*8- 6)) != 0 &&
       bloomtest(g->strbloom.cur[1], h>>(sizeof(h)*8-12)) != 0;
    if (LJ_UNLIKELY(search_fullh || collisions > max_collisions)) {
      MSize fh = lj_fullhash((const uint8_t*)str, len);
#define high6mask ((~(MSize)0)<<(sizeof(MSize)*8-6))
      fh = (fh >> 6) | (h & high6mask);
      if (search_fullh) {
        /* Recheck if the string has already been interned with "harder" hash. */
        o = gcref(g->strhash[fh & g->strmask]);
        if (LJ_LIKELY((((uintptr_t)str+len-1) & (LJ_PAGESIZE-1)) <= LJ_PAGESIZE-4)) {
          while (o != NULL) {
            GCstr *sx = gco2str(o);
            if (sx->hash == fh && sx->len == len && str_fastcmp(str, strdata(sx), len) == 0) {
              /* Resurrect if dead. Can only happen with fixstring() (keywords). */
              if (isdead(g, o)) flipwhite(o);
              g->strhash_hit++;
              return sx;  /* Return existing string. */
            }
            o = gcnext(o);
          }
        } else {  /* Slow path: end of string is too close to a page boundary. */
          while (o != NULL) {
            GCstr *sx = gco2str(o);
            if (sx->hash == fh && sx->len == len && memcmp(str, strdata(sx), len) == 0) {
              /* Resurrect if dead. Can only happen with fixstring() (keywords). */
              if (isdead(g, o)) flipwhite(o);
              g->strhash_hit++;
              return sx;  /* Return existing string. */
            }
            o = gcnext(o);
          }
        }
      }
      if (collisions > max_collisions) {
        strflags = 0xc0 | ((h>>(sizeof(h)*8-12))&0x3f);
        bloomset(g->strbloom.cur[0], h>>(sizeof(h)*8- 6));
        bloomset(g->strbloom.cur[1], h>>(sizeof(h)*8-12));
        bloomset(g->strbloom.next[0], h>>(sizeof(h)*8- 6));
        bloomset(g->strbloom.next[1], h>>(sizeof(h)*8-12));
        h = fh;
      }
    }
  }
#endif
  g->strhash_miss++;
  /* Nope, create a new string. */
  s = lj_mem_newt(L, sizeof(GCstr)+len+1, GCstr);
  newwhite(g, s);
  s->gct = ~LJ_TSTR;
  s->len = len;
  s->hash = h;
  s->reserved = 0;
  s->strflags = strflags;
  memcpy(strdatawr(s), str, len);
  strdatawr(s)[len] = '\0';  /* Zero-terminate string. */
  /* Add it to string hash table. */
  h &= g->strmask;
  s->nextgc = g->strhash[h];
  /* NOBARRIER: The string table is a GC root. */
  setgcref(g->strhash[h], obj2gco(s));
  if (g->strnum++ > g->strmask)  /* Allow a 100% load factor. */
    lj_str_resize(L, (g->strmask<<1)+1);  /* Grow string table. */
  return s;  /* Return newly interned string. */
}

void LJ_FASTCALL lj_str_free(global_State *g, GCstr *s)
{
  g->strnum--;
  lj_mem_free(g, s, sizestring(s));
}


1	/*
2	** String handling.
3	** Copyright (C) 2005-2017 Mike Pall. See Copyright Notice in luajit.h
4	*/
5
6	#define lj_str_c
7	#define LUA_CORE
8
9	#include "lj_obj.h"
10	#include "lj_gc.h"
11	#include "lj_err.h"
12	#include "lj_str.h"
13	#include "lj_char.h"
14
15	#if LUAJIT_USE_ASAN
16	/* These functions may read past a buffer end, that's ok. */
17	GCstr lj_str_new(lua_State L, const char *str, size_t lenx)
18	__attribute__((no_sanitize_address));
19
20	int32_t LJ_FASTCALL lj_str_cmp(GCstr a, GCstr b)
21	__attribute__((no_sanitize_address));
22
23	static LJ_AINLINE int str_fastcmp(const char a, const char b, MSize len)
24	__attribute__((no_sanitize_address));
25	#endif
26
27	/* -- String helpers ------------------------------------------------------ */
28
29	/* Ordered compare of strings. Assumes string data is 4-byte aligned. */
30	int32_t LJ_FASTCALL lj_str_cmp(GCstr a, GCstr b)	103,370✔
31	{
32	MSize i, n = a->len > b->len ? b->len : a->len;	103,370✔
33	for (i = 0; i < n; i += 4) {	109,869✔
34	/* Note: innocuous access up to end of string + 3. */
35	uint32_t va = (const uint32_t )(strdata(a)+i);	103,472✔
36	uint32_t vb = (const uint32_t )(strdata(b)+i);	103,472✔
37	if (va != vb) {	103,472✔
38	#if LJ_LE
39	va = lj_bswap(va); vb = lj_bswap(vb);	96,973✔
40	#endif
41	i -= n;	96,973✔
42	if ((int32_t)i >= -3) {	96,973✔
43	va >>= 32+(i<<3); vb >>= 32+(i<<3);	96,790✔
44	if (va == vb) break;	96,790✔
45	}
46	return va < vb ? -1 : 1;	96,509✔
47	}
48	}
49	return (int32_t)(a->len - b->len);	6,861✔
50	}
51
52	/* Fast string data comparison. Caveat: unaligned access to 1st string! */
53	static LJ_AINLINE int str_fastcmp(const char a, const char b, MSize len)	7,904,332✔
54	{
55	MSize i = 0;	7,904,332✔
56	lua_assert(len > 0);	15,056,445✔
57	lua_assert((((uintptr_t)a+len-1) & (LJ_PAGESIZE-1)) <= LJ_PAGESIZE-4);	15,056,445✔
58	do { /* Note: innocuous access up to end of string + 3. */	15,056,445✔
59	uint32_t v = lj_getu32(a+i) ^ (const uint32_t )(b+i);	15,056,445✔
60	if (v) {	15,056,445✔
61	i -= len;	2,569,864✔
62	#if LJ_LE
63	return (int32_t)i >= -3 ? (v << (32+(i<<3))) : 1;	2,569,864✔
64	#else
65	return (int32_t)i >= -3 ? (v >> (32+(i<<3))) : 1;
66	#endif
67	}
68	i += 4;	12,486,581✔
69	} while (i < len);	12,486,581✔
70	return 0;
71	}
72
73	/* Find fixed string p inside string s. */
74	const char lj_str_find(const char s, const char *p, MSize slen, MSize plen)	1,682✔
75	{
76	if (plen <= slen) {	1,682✔
77	if (plen == 0) {	1,608✔
78	return s;
79	} else {
80	int c = (const uint8_t )p++;	1,605✔
81	plen--; slen -= plen;	1,605✔
82	while (slen) {	3,071✔
83	const char q = (const char )memchr(s, c, slen);	3,022✔
84	if (!q) break;	3,022✔
85	if (memcmp(q+1, p, plen) == 0) return q;	1,740✔
86	q++; slen -= (MSize)(q-s); s = q;	1,466✔
87	}
88	}
89	}
90	return NULL;
91	}
92
93	/* Check whether a string has a pattern matching character. */
94	int lj_str_haspattern(GCstr *s)	1,959✔
95	{
96	const char p = strdata(s), q = p + s->len;	1,959✔
97	while (p < q) {	4,668✔
98	int c = (const uint8_t )p++;	3,609✔
99	if (lj_char_ispunct(c) && strchr("^$*+?.([%-", c))	3,609✔
100	return 1; /* Found a pattern matching char. */
101	}
102	return 0; /* No pattern matching chars found. */
103	}
104
105	/* -- String interning ---------------------------------------------------- */
106
107	/* Resize the string hash table (grow and shrink). */
108	void lj_str_resize(lua_State *L, MSize newmask)	640✔
109	{
110	global_State *g = G(L);	640✔
111	GCRef *newhash;	640✔
112	MSize i;	640✔
113	if (g->gc.state == GCSsweepstring \|\| newmask >= LJ_MAX_STRTAB-1)	640✔
114	return; /* No resizing during GC traversal or if already too big. */
115	newhash = lj_mem_newvec(L, newmask+1, GCRef);	640✔
116	memset(newhash, 0, (newmask+1)*sizeof(GCRef));	640✔
117	for (i = g->strmask; i != ~(MSize)0; i--) { /* Rehash old table. */	1,734,016✔
118	GCobj *p = gcref(g->strhash[i]);	1,733,376✔
119	while (p) { /* Follow each hash chain and reinsert all strings. */	2,434,818✔
120	MSize h = gco2str(p)->hash & newmask;	701,442✔
121	GCobj *next = gcnext(p);	701,442✔
122	/* NOBARRIER: The string table is a GC root. */
123	setgcrefr(p->gch.nextgc, newhash[h]);	701,442✔
124	setgcref(newhash[h], p);	701,442✔
125	p = next;	701,442✔
126	}
127	}
128	lj_mem_freevec(g, g->strhash, g->strmask+1, GCRef);	640✔
129	g->strmask = newmask;	640✔
130	g->strhash = newhash;	640✔
131	}
132
133	#if LUAJIT_SMART_STRINGS
134	static LJ_AINLINE uint32_t
135	lj_fullhash(const uint8_t *v, MSize len)
136	{
137	MSize a = 0, b = 0;
138	MSize c = 0xcafedead;
139	MSize d = 0xdeadbeef;
140	MSize h = len;	2,763,222✔
141	lua_assert(len >= 12);
142	for(; len>8; len-=8, v+=8) {	2,763,222✔
143	a ^= lj_getu32(v);	2,721,104✔
144	b ^= lj_getu32(v+4);	2,721,104✔
145	c += a;	2,721,104✔
146	d += b;	2,721,104✔
147	a = lj_rol(a, 5) - d;	2,721,104✔
148	b = lj_rol(b, 7) - c;	2,721,104✔
149	c = lj_rol(c, 24) ^ a;	2,721,104✔
150	d = lj_rol(d, 1) ^ b;	2,721,104✔
151	}
152	a ^= lj_getu32(v+len-8);	42,118✔
153	b ^= lj_getu32(v+len-4);	42,118✔
154	c += b; c -= lj_rol(a, 9);	42,118✔
155	d += a; d -= lj_rol(b, 18);	42,118✔
156	h -= lj_rol(a^b,7);	42,118✔
157	h += c; h += lj_rol(d,13);	42,118✔
158	d ^= c; d -= lj_rol(c,25);	42,118✔
159	h ^= d; h -= lj_rol(d,16);	42,118✔
160	c ^= h; c -= lj_rol(h,4);	42,118✔
161	d ^= c; d -= lj_rol(c,14);	42,118✔
162	h ^= d; h -= lj_rol(d,24);	42,118✔
163	return h;	42,118✔
164	}
165	#endif
166
167	/* Intern a string and return string object. */
168	GCstr lj_str_new(lua_State L, const char *str, size_t lenx)	8,307,147✔
169	{
170	global_State *g;	8,307,147✔
171	GCstr *s;	8,307,147✔
172	GCobj *o;	8,307,147✔
173	MSize len = (MSize)lenx;	8,307,147✔
174	uint8_t strflags = 0;	8,307,147✔
175	#if LUAJIT_SMART_STRINGS
176	unsigned collisions = 0;	8,307,147✔
177	#endif
178	if (lenx >= LJ_MAX_STR)	8,307,147✔
179	lj_err_msg(L, LJ_ERR_STROV);	×
180	g = G(L);	8,307,147✔
181	if (len == 0)	8,307,147✔
182	return &g->strempty;	3,682✔
183	/* Compute string hash. Constants taken from lookup3 hash by Bob Jenkins. */
184	MSize h = lua_hash(str, len);	8,303,465✔
185	/* Check if the string has already been interned. */
186	o = gcref(g->strhash[h & g->strmask]);	8,303,465✔
187	#if LUAJIT_SMART_STRINGS
188	/*
189	** The default "fast" string hash function samples only a few positions
190	** in a string, the remaining bytes don't affect the function's result.
191	** The function performs well for short strings; however long strings
192	** can yield extremely high collision rates.
193	**
194	** An adaptive schema was implemented. Two hash functions are used
195	** simultaneously. A bucket is picked based on the output of the fast
196	** hash function. If an item is to be inserted in a collision chain
197	** longer than a certain threshold, another bucket is picked based on
198	** the stronger hash function. Since two hash functions are used
199	** simultaneously, insert should consider two buckets. The second bucket
200	** is often NOT considered thanks to the bloom filter. The filter is
201	** rebuilt during GC cycle.
202	**
203	** Parameters below were tuned on a set of benchmarks. Max_collisions is
204	** also backed by theory: the expected maximum length of a collision
205	** chain in a hash table with the fill factor of 1.0 is
206	** O(log(N)/log(log(N))), assuming uniformly distributed random keys.
207	** The upper bound for N=65,000 is 10, hence 40 is a clear indication of
208	** an anomaly.
209	**/
210	#define max_collisions 40
211	#define inc_collision_soft() (collisions++)
212	/* If different strings yield the same hash sum, grow counter faster. */
213	#define inc_collision_hard() (collisions+=1+(len>>4), 1)
214	#else
215	#define inc_collision_hard() (1)
216	#define inc_collision_soft()
217	#endif
218	if (LJ_LIKELY((((uintptr_t)str+len-1) & (LJ_PAGESIZE-1)) <= LJ_PAGESIZE-4)) {	8,303,465✔
219	while (o != NULL) {	12,247,402✔
220	GCstr *sx = gco2str(o);	11,653,444✔
221	if (sx->hash == h && sx->len == len && inc_collision_hard() &&	11,653,444✔
222	str_fastcmp(str, strdata(sx), len) == 0) {	15,592,706✔
223	/* Resurrect if dead. Can only happen with fixstring() (keywords). */
224	if (isdead(g, o)) flipwhite(o);	7,708,056✔
225	g->strhash_hit++;	7,708,056✔
226	return sx; /* Return existing string. */	7,708,056✔
227	}
228	o = gcnext(o);	3,945,388✔
229	inc_collision_soft();	3,945,388✔
230	}
231	} else { /* Slow path: end of string is too close to a page boundary. */
232	while (o != NULL) {	2,439✔
233	GCstr *sx = gco2str(o);	2,320✔
234	if (sx->hash == h && sx->len == len && inc_collision_hard() &&	2,320✔
235	memcmp(str, strdata(sx), len) == 0) {	1,359✔
236	/* Resurrect if dead. Can only happen with fixstring() (keywords). */
237	if (isdead(g, o)) flipwhite(o);	1,332✔
238	g->strhash_hit++;	1,332✔
239	return sx; /* Return existing string. */	1,332✔
240	}
241	o = gcnext(o);	988✔
242	inc_collision_soft();	988✔
243	}
244	}
245	#if LUAJIT_SMART_STRINGS
246	/* "Fast" hash function consumes all bytes of a string <= 12 bytes. */
247	if (len > 12) {	594,077✔
248	/*
249	** The bloom filter is keyed with the high 12 bits of the fast
250	** hash sum. The filter is rebuilt during GC cycle. It's beneficial
251	** to have these bits readily available and avoid hash sum
252	** recalculation during GC. High 6 bits are included in the "full"
253	** hash sum, and bits 19-25 are stored in s->strflags.
254	**/
255	int search_fullh =	359,014✔
256	bloomtest(g->strbloom.cur[0], h>>(sizeof(h)*8- 6)) != 0 &&	179,507✔
257	bloomtest(g->strbloom.cur[1], h>>(sizeof(h)*8-12)) != 0;	49,789✔
258	if (LJ_UNLIKELY(search_fullh \|\| collisions > max_collisions)) {	179,507✔
259	MSize fh = lj_fullhash((const uint8_t*)str, len);	42,118✔
260	#define high6mask ((~(MSize)0)<<(sizeof(MSize)*8-6))
261	fh = (fh >> 6) \| (h & high6mask);	42,118✔
262	if (search_fullh) {	42,118✔
263	/* Recheck if the string has already been interned with "harder" hash. */
264	o = gcref(g->strhash[fh & g->strmask]);	40,811✔
265	if (LJ_LIKELY((((uintptr_t)str+len-1) & (LJ_PAGESIZE-1)) <= LJ_PAGESIZE-4)) {	40,811✔
266	while (o != NULL) {	54,140✔
267	GCstr *sx = gco2str(o);	33,013✔
268	if (sx->hash == fh && sx->len == len && str_fastcmp(str, strdata(sx), len) == 0) {	52,695✔
269	/* Resurrect if dead. Can only happen with fixstring() (keywords). */
270	if (isdead(g, o)) flipwhite(o);	19,682✔
271	g->strhash_hit++;	19,682✔
272	return sx; /* Return existing string. */	19,682✔
273	}
274	o = gcnext(o);	13,331✔
275	}
276	} else { /* Slow path: end of string is too close to a page boundary. */
277	while (o != NULL) {	5✔
278	GCstr *sx = gco2str(o);	3✔
279	if (sx->hash == fh && sx->len == len && memcmp(str, strdata(sx), len) == 0) {	3✔
280	/* Resurrect if dead. Can only happen with fixstring() (keywords). */
281	if (isdead(g, o)) flipwhite(o);	×
282	g->strhash_hit++;	×
283	return sx; /* Return existing string. */	×
284	}
285	o = gcnext(o);	3✔
286	}
287	}
288	}
289	if (collisions > max_collisions) {	22,436✔
290	strflags = 0xc0 \| ((h>>(sizeof(h)*8-12))&0x3f);	19,757✔
291	bloomset(g->strbloom.cur[0], h>>(sizeof(h)*8- 6));	19,757✔
292	bloomset(g->strbloom.cur[1], h>>(sizeof(h)*8-12));	19,757✔
293	bloomset(g->strbloom.next[0], h>>(sizeof(h)*8- 6));	19,757✔
294	bloomset(g->strbloom.next[1], h>>(sizeof(h)*8-12));	19,757✔
295	h = fh;	19,757✔
296	}
297	}
298	}
299	#endif
300	g->strhash_miss++;	574,395✔
301	/* Nope, create a new string. */
302	s = lj_mem_newt(L, sizeof(GCstr)+len+1, GCstr);	574,395✔
303	newwhite(g, s);	574,395✔
304	s->gct = ~LJ_TSTR;	574,395✔
305	s->len = len;	574,395✔
306	s->hash = h;	574,395✔
307	s->reserved = 0;	574,395✔
308	s->strflags = strflags;	574,395✔
309	memcpy(strdatawr(s), str, len);	574,395✔
310	strdatawr(s)[len] = '\0'; /* Zero-terminate string. */	574,395✔
311	/* Add it to string hash table. */
312	h &= g->strmask;	574,395✔
313	s->nextgc = g->strhash[h];	574,395✔
314	/* NOBARRIER: The string table is a GC root. */
315	setgcref(g->strhash[h], obj2gco(s));	574,395✔
316	if (g->strnum++ > g->strmask) /* Allow a 100% load factor. */	574,395✔
317	lj_str_resize(L, (g->strmask<<1)+1); /* Grow string table. */	325✔
318	return s; /* Return newly interned string. */
319	}
320
321	void LJ_FASTCALL lj_str_free(global_State g, GCstr s)	571,940✔
322	{
323	g->strnum--;	571,940✔
324	lj_mem_free(g, s, sizestring(s));	571,940✔
325	}	571,940✔
326

tarantool / luajit / 5784751762

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