boost/charconv
2
0
Fork 0
mirror of https://github.com/boostorg/charconv.git synced 2026-02-09 23:12:24 +00:00
Code Issues Projects Releases Wiki Activity

Replace std::memcpy with our memcpy

Browse Source
This commit is contained in:
Matt Borland
2023-01-27 10:52:53 -08:00
parent fb87dfff38
commit f1fac0a7ae
2 changed files with 21 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
include/boost/charconv/detail/memcpy.hpp
View File

@@ -23,10 +23,12 @@ constexpr void* memcpy(void* dest, const void* src, std::size_t count)
{
*(dest + i) = *(src + i);
}
return dest;
}
else
{
std::memcpy(dest, src, count);
return std::memcpy(dest, src, count);
}
}
@@ -36,7 +38,7 @@ constexpr void* memcpy(void* dest, const void* src, std::size_t count)
inline void* memcpy(void* dest, const void* src, std::size_t count)
{
std::memcpy(dest, src, count);
return std::memcpy(dest, src, count);
}
#endif

38
include/boost/charconv/to_chars.hpp
View File

@@ -9,6 +9,7 @@
#include <boost/charconv/detail/apply_sign.hpp>
#include <boost/charconv/detail/integer_search_trees.hpp>
#include <boost/charconv/detail/integer_conversion.hpp>
#include <boost/charconv/detail/memcpy.hpp>
#include <boost/charconv/config.hpp>
#include <type_traits>
#include <array>
@@ -79,7 +80,7 @@ namespace detail {
// See: https://jk-jeon.github.io/posts/2022/02/jeaiii-algorithm/
// https://arxiv.org/abs/2101.11408
BOOST_CXX14_CONSTEXPR char* decompose32(std::uint32_t value, char* buffer) noexcept
BOOST_CHARCONV_CONSTEXPR char* decompose32(std::uint32_t value, char* buffer) noexcept
{
constexpr auto mask = (static_cast<std::uint64_t>(1) << 57) - 1; // D = 57 so 2^D - 1
constexpr auto magic_multiplier = static_cast<std::uint64_t>(1441151881); // floor(2*D / 10*k) where D is 57 and k is 8
@@ -87,12 +88,7 @@ BOOST_CXX14_CONSTEXPR char* decompose32(std::uint32_t value, char* buffer) noexc
for (std::size_t i {}; i < 10; i += 2)
{
// Replaces std::memcpy(buffer + i, radix_table + static_cast<std::size_t>(y >> 57) * 2, 2)
// since it would not be constexpr
//const char* temp = {radix_table + static_cast<std::size_t>(y >> 57) * 2};
//buffer[i] = temp[0];
//buffer[i+1] = temp[1];
std::memcpy(buffer + i, radix_table + static_cast<std::size_t>(y >> 57) * 2, 2);
boost::charconv::detail::memcpy(buffer + i, radix_table + static_cast<std::size_t>(y >> 57) * 2, 2);
y &= mask;
y *= 100;
}
@@ -106,7 +102,7 @@ BOOST_CXX14_CONSTEXPR char* decompose32(std::uint32_t value, char* buffer) noexc
#endif
template <typename Integer>
BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* last, Integer value) noexcept
BOOST_CHARCONV_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* last, Integer value) noexcept
{
char buffer[10] {};
const std::ptrdiff_t user_buffer_size = last - first;
@@ -154,7 +150,7 @@ BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* l
*first++ = '-';
}
std::memcpy(first, buffer + (sizeof(buffer) - num_sig_chars), num_sig_chars);
boost::charconv::detail::memcpy(first, buffer + (sizeof(buffer) - num_sig_chars), num_sig_chars);
}
else if (std::numeric_limits<Integer>::digits <= std::numeric_limits<std::uint64_t>::digits ||
static_cast<std::uint64_t>(value) <= (std::numeric_limits<std::uint64_t>::max)())
@@ -180,10 +176,10 @@ BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* l
const int first_value_chars = num_digits(x);
decompose32(x, buffer);
std::memcpy(first, buffer + (sizeof(buffer) - first_value_chars), first_value_chars);
boost::charconv::detail::memcpy(first, buffer + (sizeof(buffer) - first_value_chars), first_value_chars);
decompose32(y, buffer);
std::memcpy(first + first_value_chars, buffer + 1, sizeof(buffer) - 1);
boost::charconv::detail::memcpy(first + first_value_chars, buffer + 1, sizeof(buffer) - 1);
}
else
{
@@ -195,24 +191,24 @@ BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* l
if (converted_value_digits == 19)
{
decompose32(x, buffer);
std::memcpy(first, buffer + 2, sizeof(buffer) - 2);
boost::charconv::detail::memcpy(first, buffer + 2, sizeof(buffer) - 2);
decompose32(y, buffer);
std::memcpy(first + 8, buffer + 1, sizeof(buffer) - 1);
boost::charconv::detail::memcpy(first + 8, buffer + 1, sizeof(buffer) - 1);
decompose32(z, buffer);
std::memcpy(first + 17, buffer + 8, 2);
boost::charconv::detail::memcpy(first + 17, buffer + 8, 2);
}
else // 20
{
decompose32(x, buffer);
std::memcpy(first, buffer + 1, sizeof(buffer) - 1);
boost::charconv::detail::memcpy(first, buffer + 1, sizeof(buffer) - 1);
decompose32(y, buffer);
std::memcpy(first + 9, buffer + 1, sizeof(buffer) - 1);
boost::charconv::detail::memcpy(first + 9, buffer + 1, sizeof(buffer) - 1);
decompose32(z, buffer);
std::memcpy(first + 18, buffer + 8, 2);
boost::charconv::detail::memcpy(first + 18, buffer + 8, 2);
}
}
}
@@ -236,7 +232,7 @@ BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* l
// All other bases
// Use a simple lookup table to put together the Integer in character form
template <typename Integer>
BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* last, Integer value, int base) noexcept
BOOST_CHARCONV_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* last, Integer value, int base) noexcept
{
BOOST_CHARCONV_ASSERT_MSG(base >= 2 && base <= 36, "Base must be between 2 and 36 (inclusive)");
@@ -340,7 +336,7 @@ BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* l
return {last, EOVERFLOW};
}
std::memcpy(first, buffer + (buffer_size - num_chars), num_chars);
boost::charconv::detail::memcpy(first, buffer + (buffer_size - num_chars), num_chars);
return {first + num_chars, 0};
}
@@ -348,7 +344,7 @@ BOOST_CXX14_CONSTEXPR to_chars_result to_chars_integer_impl(char* first, char* l
} // Namespace detail
template <typename Integer, typename std::enable_if<std::is_integral<Integer>::value, bool>::type = true>
BOOST_CXX14_CONSTEXPR to_chars_result to_chars(char* first, char* last, Integer value, int base = 10) noexcept
BOOST_CHARCONV_CONSTEXPR to_chars_result to_chars(char* first, char* last, Integer value, int base = 10) noexcept
{
if (base == 10)
{
@@ -359,7 +355,7 @@ BOOST_CXX14_CONSTEXPR to_chars_result to_chars(char* first, char* last, Integer
}
template <>
BOOST_CXX14_CONSTEXPR to_chars_result to_chars<bool>(char* first, char* last, bool value, int base) noexcept = delete;
BOOST_CHARCONV_CONSTEXPR to_chars_result to_chars<bool>(char* first, char* last, bool value, int base) noexcept = delete;
// TODO: Not correct, but need to make MSVC happy while working on integers
BOOST_CHARCONV_DECL to_chars_result to_chars(char* first, char* last, float value) noexcept;