fmtlib/fmt
1
0
Fork 1
mirror of https://github.com/fmtlib/fmt.git synced 2025-11-28 13:19:48 +01:00
Code Issues Packages Projects Releases Wiki Activity

Implement handmade FP

Browse Source
This commit is contained in:
Victor Zverovich
2018-04-21 17:26:24 -07:00
parent 822eccc3b8
commit cd90097ca4
3 changed files with 58 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
include/fmt/format-inl.h
View File

@@ -219,8 +219,9 @@ FMT_FUNC void system_error::init(
base = std::runtime_error(to_string(buffer));
}
namespace internal {
template <typename T>
int internal::char_traits<char>::format_float(
int char_traits<char>::format_float(
char *buffer, std::size_t size, const char *format,
unsigned width, int precision, T value) {
if (width == 0) {
@@ -234,7 +235,7 @@ int internal::char_traits<char>::format_float(
}
template <typename T>
int internal::char_traits<wchar_t>::format_float(
int char_traits<wchar_t>::format_float(
wchar_t *buffer, std::size_t size, const wchar_t *format,
unsigned width, int precision, T value) {
if (width == 0) {
@@ -248,7 +249,7 @@ int internal::char_traits<wchar_t>::format_float(
}
template <typename T>
const char internal::basic_data<T>::DIGITS[] =
const char basic_data<T>::DIGITS[] =
"0001020304050607080910111213141516171819"
"2021222324252627282930313233343536373839"
"4041424344454647484950515253545556575859"
@@ -267,18 +268,30 @@ const char internal::basic_data<T>::DIGITS[] =
factor * 1000000000
template <typename T>
const uint32_t internal::basic_data<T>::POWERS_OF_10_32[] = {
const uint32_t basic_data<T>::POWERS_OF_10_32[] = {
0, FMT_POWERS_OF_10(1)
};
template <typename T>
const uint64_t internal::basic_data<T>::POWERS_OF_10_64[] = {
const uint64_t basic_data<T>::POWERS_OF_10_64[] = {
0,
FMT_POWERS_OF_10(1),
FMT_POWERS_OF_10(1000000000ull),
10000000000000000000ull
};
FMT_FUNC fp operator*(fp x, fp y) {
// Multiply 32-bit parts of significands.
uint64_t mask = (1ULL << 32) - 1;
uint64_t a = x.f >> 32, b = x.f & mask;
uint64_t c = y.f >> 32, d = y.f & mask;
uint64_t ac = a * c, bc = b * c, ad = a * d, bd = b * d;
// Compute mid 64-bit of result and round.
uint64_t mid = (bd >> 32) + (ad & mask) + (bc & mask) + (1U << 31);
return fp(ac + (ad >> 32) + (bc >> 32) + (mid >> 32), x.e + y.e + 64);
}
} // namespace internal
#if FMT_USE_WINDOWS_H
FMT_FUNC internal::utf8_to_utf16::utf8_to_utf16(string_view s) {