cosmopolitan/libc/stdio/lcg.internal.h
Justine Tunney c776a32f75
Replace COSMO define with _COSMO_SOURCE
This change might cause ABI breakages for /opt/cosmos. It's needed to
help us better conform to header declaration practices.
2023-08-13 20:55:04 -07:00

16 lines
584 B
C

#ifndef COSMOPOLITAN_LIBC_LCG_H_
#define COSMOPOLITAN_LIBC_LCG_H_
#if !(__ASSEMBLER__ + __LINKER__ + 0)
#ifdef _COSMO_SOURCE
forceinline uint64_t KnuthLinearCongruentialGenerator(uint64_t prev[1]) {
/* Knuth, D.E., "The Art of Computer Programming," Vol 2,
Seminumerical Algorithms, Third Edition, Addison-Wesley, 1998,
p. 106 (line 26) & p. 108 */
prev[0] = prev[0] * 6364136223846793005 + 1442695040888963407;
return prev[0]; /* be sure to shift! */
}
#endif /* _COSMO_SOURCE */
#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
#endif /* COSMOPOLITAN_LIBC_LCG_H_ */