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pg_bitutils.h File Reference
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Macros

#define pg_leftmost_one_pos_size_t   pg_leftmost_one_pos64
 
#define pg_nextpower2_size_t   pg_nextpower2_64
 
#define pg_prevpower2_size_t   pg_prevpower2_64
 

Functions

static int pg_leftmost_one_pos32 (uint32 word)
 
static int pg_leftmost_one_pos64 (uint64 word)
 
static int pg_rightmost_one_pos32 (uint32 word)
 
static int pg_rightmost_one_pos64 (uint64 word)
 
static uint32 pg_nextpower2_32 (uint32 num)
 
static uint64 pg_nextpower2_64 (uint64 num)
 
static uint32 pg_prevpower2_32 (uint32 num)
 
static uint64 pg_prevpower2_64 (uint64 num)
 
static uint32 pg_ceil_log2_32 (uint32 num)
 
static uint64 pg_ceil_log2_64 (uint64 num)
 
int pg_popcount32 (uint32 word)
 
int pg_popcount64 (uint64 word)
 
uint64 pg_popcount (const char *buf, int bytes)
 
static uint32 pg_rotate_right32 (uint32 word, int n)
 
static uint32 pg_rotate_left32 (uint32 word, int n)
 

Variables

PGDLLIMPORT const uint8 pg_leftmost_one_pos [256]
 
PGDLLIMPORT const uint8 pg_rightmost_one_pos [256]
 
PGDLLIMPORT const uint8 pg_number_of_ones [256]
 

Macro Definition Documentation

◆ pg_leftmost_one_pos_size_t

#define pg_leftmost_one_pos_size_t   pg_leftmost_one_pos64

Definition at line 289 of file pg_bitutils.h.

◆ pg_nextpower2_size_t

#define pg_nextpower2_size_t   pg_nextpower2_64

Definition at line 290 of file pg_bitutils.h.

◆ pg_prevpower2_size_t

#define pg_prevpower2_size_t   pg_prevpower2_64

Definition at line 291 of file pg_bitutils.h.

Function Documentation

◆ pg_ceil_log2_32()

static uint32 pg_ceil_log2_32 ( uint32  num)
inlinestatic

Definition at line 209 of file pg_bitutils.h.

210 {
211  if (num < 2)
212  return 0;
213  else
214  return pg_leftmost_one_pos32(num - 1) + 1;
215 }
static int pg_leftmost_one_pos32(uint32 word)
Definition: pg_bitutils.h:26

References pg_leftmost_one_pos32().

Referenced by _hash_spareindex(), and my_log2().

◆ pg_ceil_log2_64()

static uint64 pg_ceil_log2_64 ( uint64  num)
inlinestatic

Definition at line 222 of file pg_bitutils.h.

223 {
224  if (num < 2)
225  return 0;
226  else
227  return pg_leftmost_one_pos64(num - 1) + 1;
228 }
static int pg_leftmost_one_pos64(uint64 word)
Definition: pg_bitutils.h:49

References pg_leftmost_one_pos64().

Referenced by GetHugePageSize(), and my_log2().

◆ pg_leftmost_one_pos32()

static int pg_leftmost_one_pos32 ( uint32  word)
inlinestatic

Definition at line 26 of file pg_bitutils.h.

27 {
28 #ifdef HAVE__BUILTIN_CLZ
29  Assert(word != 0);
30 
31  return 31 - __builtin_clz(word);
32 #else
33  int shift = 32 - 8;
34 
35  Assert(word != 0);
36 
37  while ((word >> shift) == 0)
38  shift -= 8;
39 
40  return shift + pg_leftmost_one_pos[(word >> shift) & 255];
41 #endif /* HAVE__BUILTIN_CLZ */
42 }
Assert(fmt[strlen(fmt) - 1] !='\n')
PGDLLIMPORT const uint8 pg_leftmost_one_pos[256]
Definition: pg_bitutils.c:34
static void word(struct vars *v, int dir, struct state *lp, struct state *rp)
Definition: regcomp.c:1476

References Assert(), pg_leftmost_one_pos, and word().

Referenced by _hash_get_oldblock_from_newbucket(), _hash_init_metabuffer(), add_paths_to_append_rel(), decimalLength32(), generate_union_paths(), make_main_region_dsm_handle(), pg_ceil_log2_32(), pg_nextpower2_32(), pg_prevpower2_32(), and rho().

◆ pg_leftmost_one_pos64()

static int pg_leftmost_one_pos64 ( uint64  word)
inlinestatic

Definition at line 49 of file pg_bitutils.h.

50 {
51 #ifdef HAVE__BUILTIN_CLZ
52  Assert(word != 0);
53 
54 #if defined(HAVE_LONG_INT_64)
55  return 63 - __builtin_clzl(word);
56 #elif defined(HAVE_LONG_LONG_INT_64)
57  return 63 - __builtin_clzll(word);
58 #else
59 #error must have a working 64-bit integer datatype
60 #endif
61 #else /* !HAVE__BUILTIN_CLZ */
62  int shift = 64 - 8;
63 
64  Assert(word != 0);
65 
66  while ((word >> shift) == 0)
67  shift -= 8;
68 
69  return shift + pg_leftmost_one_pos[(word >> shift) & 255];
70 #endif /* HAVE__BUILTIN_CLZ */
71 }

References Assert(), pg_leftmost_one_pos, and word().

Referenced by decimalLength64(), permute(), pg_ceil_log2_64(), pg_nextpower2_64(), pg_prevpower2_64(), and pg_prng_uint64_range().

◆ pg_nextpower2_32()

static uint32 pg_nextpower2_32 ( uint32  num)
inlinestatic

Definition at line 140 of file pg_bitutils.h.

141 {
142  Assert(num > 0 && num <= PG_UINT32_MAX / 2 + 1);
143 
144  /*
145  * A power 2 number has only 1 bit set. Subtracting 1 from such a number
146  * will turn on all previous bits resulting in no common bits being set
147  * between num and num-1.
148  */
149  if ((num & (num - 1)) == 0)
150  return num; /* already power 2 */
151 
152  return ((uint32) 1) << (pg_leftmost_one_pos32(num) + 1);
153 }
unsigned int uint32
Definition: c.h:442
#define PG_UINT32_MAX
Definition: c.h:526

References Assert(), pg_leftmost_one_pos32(), and PG_UINT32_MAX.

Referenced by _h_spoolinit(), _hash_init_metabuffer(), accumArrayResultArr(), bottomup_sort_and_shrink(), bottomup_sort_and_shrink_cmp(), enlarge_list(), ensure_record_cache_typmod_slot_exists(), ExecChooseHashTableSize(), ExecHashBuildSkewHash(), ExecParallelHashIncreaseNumBatches(), ginHeapTupleFastCollect(), LWLockRegisterTranche(), new_list(), RequestNamedLWLockTranche(), and table_block_parallelscan_startblock_init().

◆ pg_nextpower2_64()

static uint64 pg_nextpower2_64 ( uint64  num)
inlinestatic

Definition at line 163 of file pg_bitutils.h.

164 {
165  Assert(num > 0 && num <= PG_UINT64_MAX / 2 + 1);
166 
167  /*
168  * A power 2 number has only 1 bit set. Subtracting 1 from such a number
169  * will turn on all previous bits resulting in no common bits being set
170  * between num and num-1.
171  */
172  if ((num & (num - 1)) == 0)
173  return num; /* already power 2 */
174 
175  return ((uint64) 1) << (pg_leftmost_one_pos64(num) + 1);
176 }
#define PG_UINT64_MAX
Definition: c.h:529

References Assert(), pg_leftmost_one_pos64(), and PG_UINT64_MAX.

◆ pg_popcount()

uint64 pg_popcount ( const char *  buf,
int  bytes 
)

Definition at line 296 of file pg_bitutils.c.

297 {
298  uint64 popcnt = 0;
299 
300 #if SIZEOF_VOID_P >= 8
301  /* Process in 64-bit chunks if the buffer is aligned. */
302  if (buf == (const char *) TYPEALIGN(8, buf))
303  {
304  const uint64 *words = (const uint64 *) buf;
305 
306  while (bytes >= 8)
307  {
308  popcnt += pg_popcount64(*words++);
309  bytes -= 8;
310  }
311 
312  buf = (const char *) words;
313  }
314 #else
315  /* Process in 32-bit chunks if the buffer is aligned. */
316  if (buf == (const char *) TYPEALIGN(4, buf))
317  {
318  const uint32 *words = (const uint32 *) buf;
319 
320  while (bytes >= 4)
321  {
322  popcnt += pg_popcount32(*words++);
323  bytes -= 4;
324  }
325 
326  buf = (const char *) words;
327  }
328 #endif
329 
330  /* Process any remaining bytes */
331  while (bytes--)
332  popcnt += pg_number_of_ones[(unsigned char) *buf++];
333 
334  return popcnt;
335 }
#define TYPEALIGN(ALIGNVAL, LEN)
Definition: c.h:740
const uint8 pg_number_of_ones[256]
Definition: pg_bitutils.c:87
int pg_popcount64(uint64 word)
Definition: pg_bitutils.c:284
int pg_popcount32(uint32 word)
Definition: pg_bitutils.c:278
static char * buf
Definition: pg_test_fsync.c:67

References buf, pg_number_of_ones, pg_popcount32(), pg_popcount64(), and TYPEALIGN.

Referenced by bit_bit_count(), bloom_prop_bits_set(), bytea_bit_count(), heap_tuple_infomask_flags(), process_pipe_input(), and sizebitvec().

◆ pg_popcount32()

int pg_popcount32 ( uint32  word)

Definition at line 278 of file pg_bitutils.c.

279 {
280  return pg_popcount32_slow(word);
281 }
static int pg_popcount32_slow(uint32 word)
Definition: pg_bitutils.c:223

References pg_popcount32_slow(), and word().

Referenced by pg_popcount(), and plan_single_revoke().

◆ pg_popcount64()

int pg_popcount64 ( uint64  word)

Definition at line 284 of file pg_bitutils.c.

285 {
286  return pg_popcount64_slow(word);
287 }
static int pg_popcount64_slow(uint64 word)
Definition: pg_bitutils.c:245

References pg_popcount64_slow(), and word().

Referenced by pg_popcount(), and visibilitymap_count().

◆ pg_prevpower2_32()

static uint32 pg_prevpower2_32 ( uint32  num)
inlinestatic

Definition at line 186 of file pg_bitutils.h.

187 {
188  return ((uint32) 1) << pg_leftmost_one_pos32(num);
189 }

References pg_leftmost_one_pos32().

◆ pg_prevpower2_64()

static uint64 pg_prevpower2_64 ( uint64  num)
inlinestatic

Definition at line 199 of file pg_bitutils.h.

200 {
201  return ((uint64) 1) << pg_leftmost_one_pos64(num);
202 }

References pg_leftmost_one_pos64().

◆ pg_rightmost_one_pos32()

static int pg_rightmost_one_pos32 ( uint32  word)
inlinestatic

Definition at line 79 of file pg_bitutils.h.

80 {
81 #ifdef HAVE__BUILTIN_CTZ
82  Assert(word != 0);
83 
84  return __builtin_ctz(word);
85 #else
86  int result = 0;
87 
88  Assert(word != 0);
89 
90  while ((word & 255) == 0)
91  {
92  word >>= 8;
93  result += 8;
94  }
95  result += pg_rightmost_one_pos[word & 255];
96  return result;
97 #endif /* HAVE__BUILTIN_CTZ */
98 }
PGDLLIMPORT const uint8 pg_rightmost_one_pos[256]
Definition: pg_bitutils.c:62

References Assert(), pg_rightmost_one_pos, and word().

Referenced by ProcessProcSignalBarrier().

◆ pg_rightmost_one_pos64()

static int pg_rightmost_one_pos64 ( uint64  word)
inlinestatic

Definition at line 105 of file pg_bitutils.h.

106 {
107 #ifdef HAVE__BUILTIN_CTZ
108  Assert(word != 0);
109 
110 #if defined(HAVE_LONG_INT_64)
111  return __builtin_ctzl(word);
112 #elif defined(HAVE_LONG_LONG_INT_64)
113  return __builtin_ctzll(word);
114 #else
115 #error must have a working 64-bit integer datatype
116 #endif
117 #else /* !HAVE__BUILTIN_CTZ */
118  int result = 0;
119 
120  Assert(word != 0);
121 
122  while ((word & 255) == 0)
123  {
124  word >>= 8;
125  result += 8;
126  }
127  result += pg_rightmost_one_pos[word & 255];
128  return result;
129 #endif /* HAVE__BUILTIN_CTZ */
130 }

References Assert(), pg_rightmost_one_pos, and word().

◆ pg_rotate_left32()

static uint32 pg_rotate_left32 ( uint32  word,
int  n 
)
inlinestatic

Definition at line 277 of file pg_bitutils.h.

278 {
279  return (word << n) | (word >> (32 - n));
280 }

References word().

Referenced by CatalogCacheComputeHashValue(), ExecHashGetHashValue(), guc_name_hash(), hash_multirange(), hash_range(), JsonbHashScalarValue(), MemoizeHash_hash(), and TupleHashTableHash_internal().

◆ pg_rotate_right32()

static uint32 pg_rotate_right32 ( uint32  word,
int  n 
)
inlinestatic

Definition at line 271 of file pg_bitutils.h.

272 {
273  return (word >> n) | (word << (32 - n));
274 }

References word().

Referenced by ExecHashGetBucketAndBatch().

Variable Documentation

◆ pg_leftmost_one_pos

PGDLLIMPORT const uint8 pg_leftmost_one_pos[256]
extern

Definition at line 34 of file pg_bitutils.c.

Referenced by AllocSetFreeIndex(), pg_leftmost_one_pos32(), and pg_leftmost_one_pos64().

◆ pg_number_of_ones

PGDLLIMPORT const uint8 pg_number_of_ones[256]
extern

Definition at line 87 of file pg_bitutils.c.

Referenced by hemdistsign(), pg_popcount(), pg_popcount32_slow(), and pg_popcount64_slow().

◆ pg_rightmost_one_pos

PGDLLIMPORT const uint8 pg_rightmost_one_pos[256]
extern

Definition at line 62 of file pg_bitutils.c.

Referenced by pg_rightmost_one_pos32(), and pg_rightmost_one_pos64().