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/*
* Benchmark support functions.
*
* Copyright (c) 2020, Arm Limited.
* SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
*/
#include <stdint.h>
#include <time.h>
/* Fast and accurate timer returning nanoseconds. */
static inline uint64_t
clock_get_ns (void)
{
struct timespec ts;
clock_gettime (CLOCK_MONOTONIC, &ts);
return ts.tv_sec * (uint64_t) 1000000000 + ts.tv_nsec;
}
/* Fast 32-bit random number generator. Passing a non-zero seed
value resets the internal state. */
static inline uint32_t
rand32 (uint32_t seed)
{
static uint64_t state = 0xb707be451df0bb19ULL;
if (seed != 0)
state = seed;
uint32_t res = state >> 32;
state = state * 6364136223846793005ULL + 1;
return res;
}
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