ꦫꦣꦺꦤ꧀ꦄꦤ꧀ꦠꦱꦺꦤ

PATH: usr / include / mysql / server / private

This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */

#ifndef MY_BIT_INCLUDED
#define MY_BIT_INCLUDED

/*
  Some useful bit functions
*/

C_MODE_START

extern const uchar _my_bits_reverse_table[256];

/*
  my_bit_log2_xxx()

In the given value, find the highest bit set,
  which is the smallest X that satisfies the condition: (2^X >= value).
  Can be used as a reverse operation for (1<<X), to find X.

Examples:
  - returns 0 for (1<<0)
  - returns 1 for (1<<1)
  - returns 2 for (1<<2)
  - returns 2 for 3, which has (1<<2) as the highest bit set.

Note, the behaviour of log2(0) is not defined.
  Let's return 0 for the input 0, for the code simplicity.
  See the 000x branch. It covers both (1<<0) and 0.
*/
static inline CONSTEXPR uint my_bit_log2_hex_digit(uint8 value)
{
  return value & 0x0C ? /*1100*/ (value & 0x08 ? /*1000*/ 3 : /*0100*/ 2) :
                        /*0010*/ (value & 0x02 ? /*0010*/ 1 : /*000x*/ 0);
}
static inline CONSTEXPR uint my_bit_log2_uint8(uint8 value)
{
  return value & 0xF0 ? my_bit_log2_hex_digit((uint8) (value >> 4)) + 4:
                        my_bit_log2_hex_digit(value);
}
static inline CONSTEXPR uint my_bit_log2_uint16(uint16 value)
{
  return value & 0xFF00 ? my_bit_log2_uint8((uint8) (value >> 8)) + 8 :
                          my_bit_log2_uint8((uint8) value);
}
static inline CONSTEXPR uint my_bit_log2_uint32(uint32 value)
{
  return value & 0xFFFF0000UL ?
         my_bit_log2_uint16((uint16) (value >> 16)) + 16 :
         my_bit_log2_uint16((uint16) value);
}
static inline CONSTEXPR uint my_bit_log2_uint64(ulonglong value)
{
  return value & 0xFFFFFFFF00000000ULL ?
         my_bit_log2_uint32((uint32) (value >> 32)) + 32 :
         my_bit_log2_uint32((uint32) value);
}
static inline CONSTEXPR uint my_bit_log2_size_t(size_t value)
{
#ifdef __cplusplus
  static_assert(sizeof(size_t) <= sizeof(ulonglong),
                "size_t <= ulonglong is an assumption that needs to be fixed "
                "for this architecture. Please create an issue on "
                "https://jira.mariadb.org");
#endif
  return my_bit_log2_uint64((ulonglong) value);
}

/*
Count bits in 32bit integer

Algorithm by Sean Anderson, according to:
  http://graphics.stanford.edu/~seander/bithacks.html
  under "Counting bits set, in parallel"

(Original code public domain).
*/
static inline uint my_count_bits_uint32(uint32 v)
{
  v = v - ((v >> 1) & 0x55555555);
  v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
  return (((v + (v >> 4)) & 0xF0F0F0F) * 0x1010101) >> 24;
}

static inline uint my_count_bits(ulonglong x)
{
  return my_count_bits_uint32((uint32)x) + my_count_bits_uint32((uint32)(x >> 32));
}

/*
  Next highest power of two

SYNOPSIS
    my_round_up_to_next_power()
    v		Value to check

RETURN
    Next or equal power of 2
    Note: 0 will return 0

NOTES
    Algorithm by Sean Anderson, according to:
    http://graphics.stanford.edu/~seander/bithacks.html
    (Original code public domain)

Comments shows how this works with 01100000000000000000000000001011
*/

static inline uint32 my_round_up_to_next_power(uint32 v)
{
  v--;			/* 01100000000000000000000000001010 */
  v|= v >> 1;		/* 01110000000000000000000000001111 */
  v|= v >> 2;		/* 01111100000000000000000000001111 */
  v|= v >> 4;		/* 01111111110000000000000000001111 */
  v|= v >> 8;		/* 01111111111111111100000000001111 */
  v|= v >> 16;		/* 01111111111111111111111111111111 */
  return v+1;		/* 10000000000000000000000000000000 */
}

static inline uint32 my_clear_highest_bit(uint32 v)
{
  uint32 w=v >> 1;
  w|= w >> 1;
  w|= w >> 2;
  w|= w >> 4;
  w|= w >> 8;
  w|= w >> 16;
  return v & w;
}

static inline uint32 my_reverse_bits(uint32 key)
{
  return
    ((uint32)_my_bits_reverse_table[ key      & 255] << 24) |
    ((uint32)_my_bits_reverse_table[(key>> 8) & 255] << 16) |
    ((uint32)_my_bits_reverse_table[(key>>16) & 255] <<  8) |
     (uint32)_my_bits_reverse_table[(key>>24)      ];
}

/*
  a number with the n lowest bits set
  an overflow-safe version of  (1 << n) - 1
*/
static inline uint64 my_set_bits(int n)
{
  return (((1ULL << (n - 1)) - 1) << 1) | 1;
}

/* Create a mask of the significant bits for the last byte (1,3,7,..255) */
static inline uchar last_byte_mask(uint bits)
{
  /* Get the number of used bits-1 (0..7) in the last byte */
  unsigned int const used = (bits - 1U) & 7U;
  /* Return bitmask for the significant bits */
  return (uchar) ((2U << used) - 1);
}

static inline uint my_bits_in_bytes(uint n)
{
  return ((n + 7) / 8);
}

#ifdef _MSC_VER
#include <intrin.h>
#endif

/*
  Find the position of the first(least significant) bit set in
  the argument. Returns 64 if the argument was 0.
*/
static inline uint my_find_first_bit(ulonglong n)
{
  if(!n)
    return 64;
#if defined(__GNUC__)
  return __builtin_ctzll(n);
#elif defined(_MSC_VER)
#if defined(_M_IX86)
  unsigned long bit;
  if( _BitScanForward(&bit, (uint)n))
    return bit;
  _BitScanForward(&bit, (uint)(n>>32));
  return bit + 32;
#else
  unsigned long bit;
  _BitScanForward64(&bit, n);
  return bit;
#endif
#else
  /* Generic case */
  uint  shift= 0;
  static const uchar last_bit[16] = { 32, 0, 1, 0,
                                      2, 0, 1, 0,
                                      3, 0, 1, 0,
                                      2, 0, 1, 0};
  uint bit;
  while ((bit = last_bit[(n >> shift) & 0xF]) == 32)
    shift+= 4;
  return shift+bit;
#endif
}
C_MODE_END

#endif /* MY_BIT_INCLUDED */

[+] ..
[-] sql_manager.h [open]
[-] create_tmp_table.h [open]
[-] lex_ident.h [open]
[-] semisync_slave.h [open]
[-] sql_cache.h [open]
[-] events.h [open]
[-] my_rnd.h [open]
[-] lex_hash.h [open]
[-] discover.h [open]
[-] item_geofunc.h [open]
[-] wsrep_applier.h [open]
[-] my_apc.h [open]
[-] log_event.h [open]
[-] wsrep_thd.h [open]
[-] threadpool_generic.h [open]
[-] my_json_writer.h [open]
[-] mysys_err.h [open]
[-] semisync_master_ack_receiver.h [open]
[-] sql_udf.h [open]
[-] opt_trace_context.h [open]
[-] violite.h [open]
[-] rpl_mi.h [open]
[-] thr_timer.h [open]
[-] bounded_queue.h [open]
[-] item_sum.h [open]
[-] cset_narrowing.h [open]
[-] wsrep_xid.h [open]
[-] my_bitmap.h [open]
[-] table_cache.h [open]
[-] sql_locale.h [open]
[-] sql_plugin.h [open]
[-] handle_connections_win.h [open]
[-] sql_array.h [open]
[-] sql_expression_cache.h [open]
[-] password.h [open]
[-] waiting_threads.h [open]
[-] my_virtual_mem.h [open]
[-] privilege.h [open]
[-] rpl_filter.h [open]
[-] event_db_repository.h [open]
[-] thr_malloc.h [open]
[-] rpl_injector.h [open]
[-] sql_const.h [open]
[-] lex_charset.h [open]
[-] my_cpu.h [open]
[-] sql_rename.h [open]
[-] sp_cache.h [open]
[-] sql_prepare.h [open]
[-] mdl.h [open]
[-] event_scheduler.h [open]
[-] my_md5.h [open]
[-] probes_mysql.h [open]
[-] item_subselect.h [open]
[-] sql_type_geom.h [open]
[-] sql_sequence.h [open]
[-] sql_type_fixedbin.h [open]
[-] wsrep_storage_service.h [open]
[-] item_windowfunc.h [open]
[-] sql_command.h [open]
[-] uniques.h [open]
[-] rpl_record.h [open]
[-] sql_priv.h [open]
[-] sql_digest_stream.h [open]
[-] sql_callback.h [open]
[-] item_row.h [open]
[-] table.h [open]
[-] sql_profile.h [open]
[-] item_create.h [open]
[-] item_jsonfunc.h [open]
[-] sys_vars_shared.h [open]
[-] opt_trace.h [open]
[-] wsrep_types.h [open]
[-] sql_help.h [open]
[-] wsrep_on.h [open]
[-] myisamchk.h [open]
[-] my_compare.h [open]
[-] item_strfunc.h [open]
[-] proxy_protocol.h [open]
[-] wsrep.h [open]
[-] my_stack_alloc.h [open]
[-] my_nosys.h [open]
[-] sql_analyze_stmt.h [open]
[-] datadict.h [open]
[-] wqueue.h [open]
[-] mysqld_suffix.h [open]
[-] protocol.h [open]
[-] wsrep_allowlist_service.h [open]
[-] my_user.h [open]
[-] myisam.h [open]
[-] sql_trigger.h [open]
[-] json_table.h [open]
[-] sql_signal.h [open]
[-] filesort.h [open]
[-] embedded_priv.h [open]
[-] sql_type_json.h [open]
[-] sql_alter.h [open]
[-] heap.h [open]
[-] sql_delete.h [open]
[-] partition_info.h [open]
[-] message.h [open]
[-] sql_sort.h [open]
[-] wsrep_utils.h [open]
[-] rijndael.h [open]
[-] set_var.h [open]
[-] my_minidump.h [open]
[-] compat56.h [open]
[-] client_settings.h [open]
[-] thr_alarm.h [open]
[-] xa.h [open]
[-] assume_aligned.h [open]
[-] my_libwrap.h [open]
[+] atomic
[-] wsrep_status.h [open]
[-] innodb_priv.h [open]
[-] sql_load.h [open]
[-] sql_plugin_compat.h [open]
[-] sp_rcontext.h [open]
[-] wsrep_sst.h [open]
[-] sql_acl.h [open]
[-] procedure.h [open]
[-] pfs_transaction_provider.h [open]
[-] my_atomic.h [open]
[-] item_vers.h [open]
[-] sql_repl.h [open]
[-] sql_do.h [open]
[-] hash_filo.h [open]
[-] pfs_statement_provider.h [open]
[-] service_versions.h [open]
[-] sql_cmd.h [open]
[-] sql_type_string.h [open]
[-] item_timefunc.h [open]
[-] my_handler_errors.h [open]
[-] sql_crypt.h [open]
[-] scheduler.h [open]
[-] pfs_socket_provider.h [open]
[-] tzfile.h [open]
[-] rpl_rli.h [open]
[-] wsrep_mutex.h [open]
[-] keycaches.h [open]
[-] my_time.h [open]
[-] rpl_record_old.h [open]
[-] welcome_copyright_notice.h [open]
[-] item.h [open]
[-] wsrep_server_service.h [open]
[-] t_ctype.h [open]
[-] sql_debug.h [open]
[-] mysqld.h [open]
[-] item_xmlfunc.h [open]
[-] pfs_metadata_provider.h [open]
[-] gstream.h [open]
[-] sql_reload.h [open]
[-] session_tracker.h [open]
[-] config.h [open]
[-] multi_range_read.h [open]
[-] ha_handler_stats.h [open]
[-] my_counter.h [open]
[-] sql_type.h [open]
[-] probes_mysql_nodtrace.h [open]
[-] my_base.h [open]
[-] opt_subselect.h [open]
[-] repl_failsafe.h [open]
[-] handler.h [open]
[-] wsrep_mysqld_c.h [open]
[-] records.h [open]
[-] backup.h [open]
[-] sql_bitmap.h [open]
[-] sql_binlog.h [open]
[-] log_event_data_type.h [open]
[-] wsrep_client_service.h [open]
[-] lex_symbol.h [open]
[-] sql_lex.h [open]
[-] ddl_log.h [open]
[-] create_options.h [open]
[-] group_by_handler.h [open]
[-] strfunc.h [open]
[-] my_service_manager.h [open]
[-] semisync_master.h [open]
[-] sql_db.h [open]
[-] sql_insert.h [open]
[-] my_stacktrace.h [open]
[-] lex.h [open]
[-] item_cmpfunc.h [open]
[-] sql_type_int.h [open]
[-] wsrep_var.h [open]
[-] maria.h [open]
[-] event_data_objects.h [open]
[-] sql_handler.h [open]
[-] source_revision.h [open]
[-] debug.h [open]
[-] rpl_gtid.h [open]
[-] key.h [open]
[-] sql_servers.h [open]
[-] lex_string.h [open]
[-] myisampack.h [open]
[-] rpl_tblmap.h [open]
[-] sql_type_fixedbin_storage.h [open]
[-] my_crypt.h [open]
[-] structs.h [open]
[-] sql_table.h [open]
[-] field.h [open]
[-] sql_plist.h [open]
[-] replication.h [open]
[-] select_handler.h [open]
[-] winservice.h [open]
[-] win_tzname_data.h [open]
[-] slave.h [open]
[-] init.h [open]
[-] sql_get_diagnostics.h [open]
[-] sp_head.h [open]
[-] custom_conf.h [open]
[-] sql_join_cache.h [open]
[-] sql_audit.h [open]
[-] sql_connect.h [open]
[-] wsrep_server_state.h [open]
[+] data
[-] sql_update.h [open]
[-] transaction.h [open]
[-] log_event_old.h [open]
[-] pfs_stage_provider.h [open]
[-] mariadb.h [open]
[-] item_func.h [open]
[-] my_tree.h [open]
[-] sql_tvc.h [open]
[-] rpl_reporting.h [open]
[-] derror.h [open]
[-] sql_schema.h [open]
[-] sql_parse.h [open]
[-] sql_type_real.h [open]
[-] pfs_thread_provider.h [open]
[-] my_check_opt.h [open]
[-] rowid_filter.h [open]
[-] sql_base.h [open]
[-] sql_test.h [open]
[-] sp.h [open]
[-] my_uctype.h [open]
[-] myisammrg.h [open]
[-] sp_pcontext.h [open]
[-] my_bit.h [open]
[-] wsrep_client_state.h [open]
[-] event_queue.h [open]
[-] sql_window.h [open]
[-] sql_limit.h [open]
[-] my_rdtsc.h [open]
[-] sql_list.h [open]
[-] pfs_file_provider.h [open]
[-] rpl_constants.h [open]
[-] sql_explain.h [open]
[-] sql_class.h [open]
[-] sql_i_s.h [open]
[-] sql_lifo_buffer.h [open]
[-] pfs_memory_provider.h [open]
[-] ssl_compat.h [open]
[-] wsrep_mysqld.h [open]
[-] dur_prop.h [open]
[-] sql_union.h [open]
[-] field_comp.h [open]
[-] contributors.h [open]
[-] pfs_table_provider.h [open]
[-] wsrep_condition_variable.h [open]
[-] wsrep_trans_observer.h [open]
[-] rpl_parallel.h [open]
[-] parse_file.h [open]
[-] my_atomic_wrapper.h [open]
[-] sql_alloc.h [open]
[-] threadpool_winsockets.h [open]
[-] sql_show.h [open]
[-] sql_mode.h [open]
[-] gcalc_tools.h [open]
[-] hash.h [open]
[-] sql_partition.h [open]
[-] mysqld_default_groups.h [open]
[-] sql_truncate.h [open]
[-] mem_root_array.h [open]
[-] sql_basic_types.h [open]
[-] socketpair.h [open]
[-] lex_token.h [open]
[-] thr_lock.h [open]
[+] providers
[-] authors.h [open]
[-] sql_error.h [open]
[-] threadpool.h [open]
[-] opt_range.h [open]
[-] log_slow.h [open]
[-] debug_sync.h [open]
[-] ha_partition.h [open]
[-] sql_derived.h [open]
[-] sql_bootstrap.h [open]
[-] gcalc_slicescan.h [open]
[-] queues.h [open]
[-] aria_backup.h [open]
[-] aligned.h [open]
[-] partition_element.h [open]
[-] spatial.h [open]
[-] semisync.h [open]
[-] my_default.h [open]
[-] sql_hset.h [open]
[-] sql_cte.h [open]
[-] opt_histogram_json.h [open]
[-] scope.h [open]
[-] event_parse_data.h [open]
[-] ilist.h [open]
[-] sql_view.h [open]
[-] wsrep_schema.h [open]
[-] lock.h [open]
[-] sql_admin.h [open]
[-] sql_partition_admin.h [open]
[-] vers_string.h [open]
[-] ha_sequence.h [open]
[-] sql_cursor.h [open]
[-] sql_string.h [open]
[-] sql_statistics.h [open]
[-] tztime.h [open]
[-] my_alarm.h [open]
[-] my_decimal.h [open]
[-] sql_analyse.h [open]
[-] sql_digest.h [open]
[-] unireg.h [open]
[-] hostname.h [open]
[-] ft_global.h [open]
[-] grant.h [open]
[-] wsrep_priv.h [open]
[-] log.h [open]
[-] filesort_utils.h [open]
[-] sql_time.h [open]
[-] sql_select.h [open]
[-] wsrep_binlog.h [open]
[-] wsrep_high_priority_service.h [open]
[-] pfs_idle_provider.h [open]
[-] derived_handler.h [open]
[-] thread_cache.h [open]
[-] lf.h [open]
[-] des_key_file.h [open]
[-] span.h [open]
[-] rpl_utility.h [open]