Skip to content

[libc] Add handling for long double=double double #113235

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Oct 22, 2024
Merged

[libc] Add handling for long double=double double #113235

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions libc/src/__support/macros/properties/types.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,8 @@
#define LIBC_TYPES_LONG_DOUBLE_IS_X86_FLOAT80
#elif (LDBL_MANT_DIG == 113)
#define LIBC_TYPES_LONG_DOUBLE_IS_FLOAT128
#elif (LDBL_MANT_DIG == 103)
#define LIBC_TYPES_LONG_DOUBLE_IS_DOUBLE_DOUBLE
#endif

// int64 / uint64 support
Expand Down
20 changes: 18 additions & 2 deletions libc/src/__support/str_to_float.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -195,7 +195,10 @@ eisel_lemire(ExpandedFloat<T> init_num,
return output;
}

#if !defined(LIBC_TYPES_LONG_DOUBLE_IS_FLOAT64)
// TODO: Re-enable eisel-lemire for long double is double double once it's
// properly supported.
#if !defined(LIBC_TYPES_LONG_DOUBLE_IS_FLOAT64) && \
!defined(LIBC_TYPES_LONG_DOUBLE_IS_DOUBLE_DOUBLE)
template <>
LIBC_INLINE cpp::optional<ExpandedFloat<long double>>
eisel_lemire<long double>(ExpandedFloat<long double> init_num,
Expand Down Expand Up @@ -316,7 +319,8 @@ eisel_lemire<long double>(ExpandedFloat<long double> init_num,
output.exponent = exp2;
return output;
}
#endif // !defined(LIBC_TYPES_LONG_DOUBLE_IS_FLOAT64)
#endif // !defined(LIBC_TYPES_LONG_DOUBLE_IS_FLOAT64) &&
// !defined(LIBC_TYPES_LONG_DOUBLE_IS_DOUBLE_DOUBLE)

// The nth item in POWERS_OF_TWO represents the greatest power of two less than
// 10^n. This tells us how much we can safely shift without overshooting.
Expand Down Expand Up @@ -518,6 +522,18 @@ template <> class ClingerConsts<long double> {
static constexpr long double MAX_EXACT_INT =
10384593717069655257060992658440191.0L;
};
#elif defined(LIBC_TYPES_LONG_DOUBLE_IS_DOUBLE_DOUBLE)
// TODO: Add proper double double type support here, currently using constants
// for double since it should be safe.
template <> class ClingerConsts<long double> {
public:
static constexpr double POWERS_OF_TEN_ARRAY[] = {
1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11,
1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};
static constexpr int32_t EXACT_POWERS_OF_TEN = 22;
static constexpr int32_t DIGITS_IN_MANTISSA = 15;
static constexpr double MAX_EXACT_INT = 9007199254740991.0;
};
#else
#error "Unknown long double type"
#endif
Expand Down
Loading