Files
Abdelrahman Said a11edf0c53 Add graph references
2026-06-28 13:49:01 +01:00

379 lines
11 KiB
C

/*
* PCG Random Number Generation for C.
*
* Copyright 2014-2019 Melissa O'Neill <oneill@pcg-random.org>,
* and the PCG Project contributors.
*
* SPDX-License-Identifier: (Apache-2.0 OR MIT)
*
* Licensed under the Apache License, Version 2.0 (provided in
* LICENSE-APACHE.txt and at http://www.apache.org/licenses/LICENSE-2.0)
* or under the MIT license (provided in LICENSE-MIT.txt and at
* http://opensource.org/licenses/MIT), at your option. This file may not
* be copied, modified, or distributed except according to those terms.
*
* Distributed on an "AS IS" BASIS, WITHOUT WARRANTY OF ANY KIND, either
* express or implied. See your chosen license for details.
*
* For additional information about the PCG random number generation scheme,
* visit http://www.pcg-random.org/.
*/
/*
* This code is derived from the canonical C++ PCG implementation, which
* has many additional features and is preferable if you can use C++ in
* your project.
*
* The contents of this file were mechanically derived from pcg_variants.h
* (every inline function defined there gets a generated extern declaration).
*/
#include "pcg_variants.h"
/* Functions to advance the underlying LCG, one version for each size and
* each style. These functions are considered semi-private. There is rarely
* a good reason to call them directly.
*/
#if PCG_HAS_128BIT_OPS
extern inline void pcg_oneseq_128_step_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_oneseq_128_advance_r(struct pcg_state_128* rng,
pcg128_t delta);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_mcg_128_step_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_mcg_128_advance_r(struct pcg_state_128* rng,
pcg128_t delta);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_unique_128_step_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_unique_128_advance_r(struct pcg_state_128* rng,
pcg128_t delta);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_setseq_128_step_r(struct pcg_state_setseq_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_setseq_128_advance_r(struct pcg_state_setseq_128* rng,
pcg128_t delta);
#endif
/* Functions to seed the RNG state, one version for each size and each
* style. Unlike the step functions, regular users can and should call
* these functions.
*/
#if PCG_HAS_128BIT_OPS
extern inline void pcg_oneseq_128_srandom_r(struct pcg_state_128* rng,
pcg128_t initstate);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_mcg_128_srandom_r(struct pcg_state_128* rng,
pcg128_t initstate);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_unique_128_srandom_r(struct pcg_state_128* rng,
pcg128_t initstate);
#endif
#if PCG_HAS_128BIT_OPS
extern inline void pcg_setseq_128_srandom_r(struct pcg_state_setseq_128* rng,
pcg128_t initstate,
pcg128_t initseq);
#endif
/* Now, finally we create each of the individual generators. We provide
* a random_r function that provides a random number of the appropriate
* type (using the full range of the type) and a boundedrand_r version
* that provides
*
* Implementation notes for boundedrand_r:
*
* To avoid bias, we need to make the range of the RNG a multiple of
* bound, which we do by dropping output less than a threshold.
* Let's consider a 32-bit case... A naive scheme to calculate the
* threshold would be to do
*
* uint32_t threshold = 0x100000000ull % bound;
*
* but 64-bit div/mod is slower than 32-bit div/mod (especially on
* 32-bit platforms). In essence, we do
*
* uint32_t threshold = (0x100000000ull-bound) % bound;
*
* because this version will calculate the same modulus, but the LHS
* value is less than 2^32.
*
* (Note that using modulo is only wise for good RNGs, poorer RNGs
* such as raw LCGs do better using a technique based on division.)
* Empirical tests show that division is preferable to modulus for
* reducing the range of an RNG. It's faster, and sometimes it can
* even be statistically prefereable.
*/
/* Generation functions for XSH RS */
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_xsh_rs_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_xsh_rs_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_xsh_rs_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_xsh_rs_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_xsh_rs_64_random_r(struct pcg_state_setseq_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_xsh_rs_64_boundedrand_r(struct pcg_state_setseq_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_mcg_128_xsh_rs_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_mcg_128_xsh_rs_64_boundedrand_r(struct pcg_state_128* rng, uint64_t bound);
#endif
/* Generation functions for XSH RR */
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_xsh_rr_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_xsh_rr_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_xsh_rr_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_xsh_rr_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_xsh_rr_64_random_r(struct pcg_state_setseq_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_xsh_rr_64_boundedrand_r(struct pcg_state_setseq_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_mcg_128_xsh_rr_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_mcg_128_xsh_rr_64_boundedrand_r(struct pcg_state_128* rng, uint64_t bound);
#endif
/* Generation functions for RXS M XS (no MCG versions because they
* don't make sense when you want to use the entire state)
*/
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_oneseq_128_rxs_m_xs_128_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_oneseq_128_rxs_m_xs_128_boundedrand_r(struct pcg_state_128* rng,
pcg128_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_unique_128_rxs_m_xs_128_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_unique_128_rxs_m_xs_128_boundedrand_r(struct pcg_state_128* rng,
pcg128_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_setseq_128_rxs_m_xs_128_random_r(struct pcg_state_setseq_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_setseq_128_rxs_m_xs_128_boundedrand_r(struct pcg_state_setseq_128* rng,
pcg128_t bound);
#endif
/* Generation functions for RXS M */
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_rxs_m_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_rxs_m_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_rxs_m_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_rxs_m_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_rxs_m_64_random_r(struct pcg_state_setseq_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_rxs_m_64_boundedrand_r(struct pcg_state_setseq_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t pcg_mcg_128_rxs_m_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_mcg_128_rxs_m_64_boundedrand_r(struct pcg_state_128* rng, uint64_t bound);
#endif
/* Generation functions for XSL RR (only defined for "large" types) */
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_xsl_rr_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_oneseq_128_xsl_rr_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_xsl_rr_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_unique_128_xsl_rr_64_boundedrand_r(struct pcg_state_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_xsl_rr_64_random_r(struct pcg_state_setseq_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_setseq_128_xsl_rr_64_boundedrand_r(struct pcg_state_setseq_128* rng,
uint64_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_mcg_128_xsl_rr_64_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline uint64_t
pcg_mcg_128_xsl_rr_64_boundedrand_r(struct pcg_state_128* rng, uint64_t bound);
#endif
/* Generation functions for XSL RR RR (only defined for "large" types) */
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_oneseq_128_xsl_rr_rr_128_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_oneseq_128_xsl_rr_rr_128_boundedrand_r(struct pcg_state_128* rng,
pcg128_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_unique_128_xsl_rr_rr_128_random_r(struct pcg_state_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_unique_128_xsl_rr_rr_128_boundedrand_r(struct pcg_state_128* rng,
pcg128_t bound);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_setseq_128_xsl_rr_rr_128_random_r(struct pcg_state_setseq_128* rng);
#endif
#if PCG_HAS_128BIT_OPS
extern inline pcg128_t
pcg_setseq_128_xsl_rr_rr_128_boundedrand_r(struct pcg_state_setseq_128* rng,
pcg128_t bound);
#endif