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* code cleanup.

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This commit is contained in:
IRainman 2025-11-09 17:22:13 +03:00
parent e109eedd35
commit b9d91e7f34
2 changed files with 21 additions and 22 deletions
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27
include/fast_float/bigint.h
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@ -535,19 +535,17 @@ struct bigint : pow5_tables<> {
// we can't shift more than the capacity of the vector. // we can't shift more than the capacity of the vector.
return false; return false;
} }
if (vec.is_empty()) { if (!vec.is_empty()) {
// nothing to do // move limbs
return true; limb *dst = vec.data + n;
limb const *src = vec.data;
std::copy_backward(src, src + vec.len(), dst + vec.len());
// fill in empty limbs
limb *first = vec.data;
limb *last = first + n;
::std::fill(first, last, 0);
vec.set_len(limb_t(n + vec.len()));
} }
// move limbs
limb *dst = vec.data + n;
limb const *src = vec.data;
std::copy_backward(src, src + vec.len(), dst + vec.len());
// fill in empty limbs
limb *first = vec.data;
limb *last = first + n;
::std::fill(first, last, 0);
vec.set_len(limb_t(n + vec.len()));
return true; return true;
} }
@ -590,12 +588,14 @@ struct bigint : pow5_tables<> {
FASTFLOAT_CONSTEXPR20 bool add(limb y) noexcept { return small_add(vec, y); } FASTFLOAT_CONSTEXPR20 bool add(limb y) noexcept { return small_add(vec, y); }
// multiply as if by 2 raised to a power. // multiply as if by 2 raised to a power.
FASTFLOAT_CONSTEXPR20 bool pow2(am_pow_t exp) noexcept { FASTFLOAT_CONSTEXPR20 bool pow2(am_pow_t const exp) noexcept {
FASTFLOAT_ASSERT(exp >= 0);
return shl(static_cast<fast_float::bigint_bits_t>(exp)); return shl(static_cast<fast_float::bigint_bits_t>(exp));
} }
// multiply as if by 5 raised to a power. // multiply as if by 5 raised to a power.
FASTFLOAT_CONSTEXPR20 bool pow5(am_pow_t exp) noexcept { FASTFLOAT_CONSTEXPR20 bool pow5(am_pow_t exp) noexcept {
FASTFLOAT_ASSERT(exp >= 0);
// multiply by a power of 5 // multiply by a power of 5
limb_t const large_length = sizeof(large_power_of_5) / sizeof(limb); limb_t const large_length = sizeof(large_power_of_5) / sizeof(limb);
limb_span const large = limb_span(large_power_of_5, large_length); limb_span const large = limb_span(large_power_of_5, large_length);
@ -627,6 +627,7 @@ struct bigint : pow5_tables<> {
// multiply as if by 10 raised to a power. // multiply as if by 10 raised to a power.
FASTFLOAT_CONSTEXPR20 bool pow10(am_pow_t exp) noexcept { FASTFLOAT_CONSTEXPR20 bool pow10(am_pow_t exp) noexcept {
FASTFLOAT_ASSERT(exp >= 0);
FASTFLOAT_TRY(pow5(exp)); FASTFLOAT_TRY(pow5(exp));
return pow2(exp); return pow2(exp);
} }

16
include/fast_float/digit_comparison.h
View File

@ -373,11 +373,9 @@ inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa positive_digit_comp(
// we then need to scale by `2^(f- e)`, and then the two significant digits // we then need to scale by `2^(f- e)`, and then the two significant digits
// are of the same magnitude. // are of the same magnitude.
template <typename T> template <typename T>
inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa negative_digit_comp( inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
bigint &bigmant, adjusted_mantissa am, am_pow_t const exponent) noexcept { negative_digit_comp(bigint &real_digits, adjusted_mantissa am,
bigint &real_digits = bigmant; am_pow_t const real_exp) noexcept {
am_pow_t const &real_exp = exponent;
// get the value of `b`, rounded down, and get a bigint representation of // get the value of `b`, rounded down, and get a bigint representation of
// b+h // b+h
adjusted_mantissa am_b = am; adjusted_mantissa am_b = am;
@ -391,12 +389,12 @@ inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa negative_digit_comp(
false, false,
#endif #endif
am_b, b); am_b, b);
adjusted_mantissa theor = to_extended_halfway(b); adjusted_mantissa const theor = to_extended_halfway(b);
bigint theor_digits(theor.mantissa); bigint theor_digits(theor.mantissa);
am_pow_t theor_exp = theor.power2; am_pow_t const theor_exp = theor.power2;
// scale real digits and theor digits to be same power. // scale real digits and theor digits to be same power.
am_pow_t pow2_exp = theor_exp - real_exp; am_pow_t const pow2_exp = theor_exp - real_exp;
am_pow_t pow5_exp = -real_exp; am_pow_t pow5_exp = -real_exp;
if (pow5_exp != 0) { if (pow5_exp != 0) {
FASTFLOAT_ASSERT(theor_digits.pow5(pow5_exp)); FASTFLOAT_ASSERT(theor_digits.pow5(pow5_exp));
@ -408,7 +406,7 @@ inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa negative_digit_comp(
} }
// compare digits, and use it to direct rounding // compare digits, and use it to direct rounding
int ord = real_digits.compare(theor_digits); int const ord = real_digits.compare(theor_digits);
round<T>(am, [ord](adjusted_mantissa &a, am_pow_t shift) { round<T>(am, [ord](adjusted_mantissa &a, am_pow_t shift) {
round_nearest_tie_even( round_nearest_tie_even(
a, shift, [ord](bool is_odd, bool _, bool __) -> bool { a, shift, [ord](bool is_odd, bool _, bool __) -> bool {