46 lines
1.1 KiB
C
46 lines
1.1 KiB
C
/*------------------------------------------------------------------------
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*
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* geqo_random.c
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* random number generator
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*
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* Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* src/backend/optimizer/geqo/geqo_random.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "optimizer/geqo_random.h"
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void
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geqo_set_seed(PlannerInfo *root, double seed)
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{
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GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
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pg_prng_fseed(&private->random_state, seed);
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}
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double
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geqo_rand(PlannerInfo *root)
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{
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GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
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return pg_prng_double(&private->random_state);
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}
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int
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geqo_randint(PlannerInfo *root, int upper, int lower)
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{
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GeqoPrivateData *private = (GeqoPrivateData *) root->join_search_private;
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/*
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* In current usage, "lower" is never negative so we can just use
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* pg_prng_uint64_range directly.
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*/
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return (int) pg_prng_uint64_range(&private->random_state, lower, upper);
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}
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