test-tokutime-riscv.c

#include <stdio.h>
#include <stdint.h>
#include <sys/time.h>
#include <time.h>
#include <inttypes.h>

static inline uint64_t toku_time_now(void) {
#if defined(__x86_64__) || defined(__i386__)
  uint32_t lo, hi;
  __asm__ __volatile__("rdtsc" : "=a"(lo), "=d"(hi));
  return (uint64_t)hi << 32 | lo;
#elif defined(__aarch64__)
  uint64_t result;
  __asm __volatile__("mrs %[rt], cntvct_el0" : [ rt ] "=r"(result));
  return result;
#elif defined(__powerpc__)
  return __ppc_get_timebase();
#elif defined(__s390x__)
  uint64_t result;
  asm volatile("stckf %0" : "=Q"(result) : : "cc");
  return result;
#elif defined(__riscv) && __riscv_xlen == 32
  uint32_t cycles_lo, cycles_hi0, cycles_hi1;
  // Implemented in assembly because Clang insisted on branching.
  asm volatile(
    "rdcycleh %0\n"
    "rdcycle %1\n"
    "rdcycleh %2\n"
    "sub %0, %0, %2\n"
    "seqz %0, %0\n"
    "sub %0, zero, %0\n"
    "and %1, %1, %0\n"
    : "=r"(cycles_hi0), "=r"(cycles_lo), "=r"(cycles_hi1));
  return (static_cast<uint64_t>(cycles_hi1) << 32) | cycles_lo;
#elif defined(__riscv) && __riscv_xlen == 64
  uint64_t cycles;
  asm volatile("rdcycle %0" : "=r"(cycles));
  return cycles;
#else
#error No timer implementation for this platform
#endif
}

int main() {
  printf("%" PRIu64 "\n", toku_time_now());
  return 0;
}