TLA  Line data    Source code

       1                 : /*------------------------------------------------------------------------
       2                 :  *
       3                 :  * geqo_random.c
       4                 :  *     random number generator
       5                 :  *
       6                 :  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
       7                 :  * Portions Copyright (c) 1994, Regents of the University of California
       8                 :  *
       9                 :  * src/backend/optimizer/geqo/geqo_random.c
      10                 :  *
      11                 :  *-------------------------------------------------------------------------
      12                 :  */
      13                 : 
      14                 : #include "postgres.h"
      15                 : 
      16                 : #include "optimizer/geqo_random.h"
      17                 : 
      18                 : 
      19                 : void
      20 CBC           3 : geqo_set_seed(PlannerInfo *root, double seed)
      21                 : {
      22               3 :     GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
      23                 : 
      24               3 :     pg_prng_fseed(&private->random_state, seed);
      25               3 : }
      26                 : 
      27                 : double
      28             390 : geqo_rand(PlannerInfo *root)
      29                 : {
      30             390 :     GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
      31                 : 
      32             390 :     return pg_prng_double(&private->random_state);
      33                 : }
      34                 : 
      35                 : int
      36            1155 : geqo_randint(PlannerInfo *root, int upper, int lower)
      37                 : {
      38            1155 :     GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
      39                 : 
      40                 :     /*
      41                 :      * In current usage, "lower" is never negative so we can just use
      42                 :      * pg_prng_uint64_range directly.
      43                 :      */
      44            1155 :     return (int) pg_prng_uint64_range(&private->random_state, lower, upper);
      45                 : }