FMT_FUNC bool grisu2_gen_digits()

in src/main/cpp/sdk/common/spdlog/fmt/bundled/format-inl.h [484:531]

• 44 lines of code
• 19 McCabe index (conditional complexity)

FMT_FUNC bool grisu2_gen_digits(
    char *buf, int &size, uint32_t hi, uint64_t lo, int &exp,
    uint64_t delta, const fp &one, const fp &diff, int max_digits) {
  // Generate digits for the most significant part (hi).
  while (exp > 0) {
    uint32_t digit = 0;
    // This optimization by miloyip reduces the number of integer divisions by
    // one per iteration.
    switch (exp) {
    case 10: digit = hi / 1000000000; hi %= 1000000000; break;
    case  9: digit = hi /  100000000; hi %=  100000000; break;
    case  8: digit = hi /   10000000; hi %=   10000000; break;
    case  7: digit = hi /    1000000; hi %=    1000000; break;
    case  6: digit = hi /     100000; hi %=     100000; break;
    case  5: digit = hi /      10000; hi %=      10000; break;
    case  4: digit = hi /       1000; hi %=       1000; break;
    case  3: digit = hi /        100; hi %=        100; break;
    case  2: digit = hi /         10; hi %=         10; break;
    case  1: digit = hi;              hi =           0; break;
    default:
      FMT_ASSERT(false, "invalid number of digits");
    }
    if (digit != 0 || size != 0)
      buf[size++] = static_cast<char>('0' + digit);
    --exp;
    uint64_t remainder = (static_cast<uint64_t>(hi) << -one.e) + lo;
    if (remainder <= delta || size > max_digits) {
      return grisu2_round(
            buf, size, max_digits, delta, remainder,
            static_cast<uint64_t>(data::POWERS_OF_10_32[exp]) << -one.e,
            diff.f, exp);
    }
  }
  // Generate digits for the least significant part (lo).
  for (;;) {
    lo *= 10;
    delta *= 10;
    char digit = static_cast<char>(lo >> -one.e);
    if (digit != 0 || size != 0)
      buf[size++] = static_cast<char>('0' + digit);
    lo &= one.f - 1;
    --exp;
    if (lo < delta || size > max_digits) {
      return grisu2_round(buf, size, max_digits, delta, lo, one.f,
                          diff.f * data::POWERS_OF_10_32[-exp], exp);
    }
  }
}