mirror of
https://github.com/nlohmann/json.git
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Binary readers: swap the bytes of floats with a single byteswap
byte_swap reversed float and double values byte by byte. GCC does not merge that loop into one bswap, and C++23's std::byteswap accepts only integers. Overloads for float and double now copy the bits into a uint32_t/uint64_t, call detail::byteswap, and copy them back. This applies to every binary reader that uses get_number. In the CBOR reader, the single- and double-precision float cases call a non-inlined helper. Without it, GCC stopped inlining the stream adapter's get_character() into parse_cbor_internal, which made reading from a std::istream about 0.5 % slower. Signed-off-by: Niels Lohmann <mail@nlohmann.me>
This commit is contained in:
2 files changed
+294
-241
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@@ -22,6 +22,7 @@
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#include <bit> //byteswap
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#endif
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#include <nlohmann/detail/bit_ops.hpp>
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#include <nlohmann/detail/exceptions.hpp>
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#include <nlohmann/detail/input/input_adapters.hpp>
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#include <nlohmann/detail/input/json_sax.hpp>
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@@ -1135,16 +1136,10 @@ class binary_reader
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return get_half_float(false);
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case 0xFA: // Single-Precision Float (four-byte IEEE 754)
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{
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float number{};
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return get_number(number) && emit_float(number);
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}
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return get_cbor_float<float>();
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case 0xFB: // Double-Precision Float (eight-byte IEEE 754)
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{
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double number{};
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return get_number(number) && emit_float(number);
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}
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return get_cbor_float<double>();
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default: // anything else (0xFF is handled inside the other types)
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{
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@@ -1153,6 +1148,16 @@ class binary_reader
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}
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}
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/// read a single- or double-precision float (kept out of
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/// parse_cbor_value, which is inlined into parse_cbor_internal)
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template<typename NumberType>
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JSON_HEDLEY_NEVER_INLINE
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bool get_cbor_float()
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{
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NumberType number{};
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return get_number(number) && emit_float(number);
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}
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/*!
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@brief reports a nested indefinite-length CBOR string or byte array
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@param[in] type_name name of the rejected string type
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@@ -4220,6 +4225,27 @@ class binary_reader
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return current;
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}
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/// reverse the byte order of a double with a single byteswap(): GCC does
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/// not merge the byte-wise swap of the generic version into one
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static void byte_swap(double& number) noexcept
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{
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static_assert(sizeof(double) == sizeof(std::uint64_t), "double must have 64 bits");
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std::uint64_t bits{};
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std::memcpy(&bits, &number, sizeof(bits));
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bits = byteswap(bits);
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std::memcpy(&number, &bits, sizeof(bits));
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}
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/// reverse the byte order of a float with a single byteswap()
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static void byte_swap(float& number) noexcept
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{
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static_assert(sizeof(float) == sizeof(std::uint32_t), "float must have 32 bits");
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std::uint32_t bits{};
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std::memcpy(&bits, &number, sizeof(bits));
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bits = byteswap(bits);
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std::memcpy(&number, &bits, sizeof(bits));
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}
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template<class NumberType>
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static void byte_swap(NumberType& number)
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{
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Generated
+260
-233
@@ -8852,6 +8852,233 @@ NLOHMANN_JSON_NAMESPACE_END
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#include <bit> //byteswap
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#endif
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// #include <nlohmann/detail/bit_ops.hpp>
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// __ _____ _____ _____
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// __| | __| | | | JSON for Modern C++
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// | | |__ | | | | | | version 3.12.0
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// |_____|_____|_____|_|___| https://github.com/nlohmann/json
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//
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// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>
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// SPDX-License-Identifier: MIT
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#include <cstdint> // uint64_t
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#include <cstring> // memcpy
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#if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_ARM64)) && (!defined(__SIZEOF_INT128__) || (!defined(__GNUC__) && !defined(__clang__)))
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#include <intrin0.h> // __umulh, _umul128, _BitScanForward64, _BitScanReverse64
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#endif
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#ifdef _MSC_VER
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#include <cstdlib> // _byteswap_ushort, _byteswap_ulong, _byteswap_uint64
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#endif
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#if defined(_MSC_VER) && !defined(__clang__) && (defined(_M_IX86) || defined(_M_ARM))
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#include <intrin.h> // _BitScanForward, _BitScanReverse
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#endif
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// #include <nlohmann/detail/macro_scope.hpp>
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// JSON_HEDLEY_ALWAYS_INLINE, NLOHMANN_JSON_NAMESPACE_BEGIN
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#if defined(__cpp_lib_bit_cast) || defined(__cpp_lib_bitops) || defined(__cpp_lib_byteswap)
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#include <bit> // bit_cast, byteswap, countl_zero, countr_zero
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#endif
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// Portable bit-level helpers for the number and string scanners. They use
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// compiler builtins or platform-specific intrinsics where available, the
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// C++20 <bit> functions next, and plain C++ otherwise, so they work regardless
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// of byte order. (The builtins and intrinsics come first: MSVC's
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// std::countl_zero checks for LZCNT at run time unless AVX2 is enabled.)
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NLOHMANN_JSON_NAMESPACE_BEGIN
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namespace detail
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{
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/// number of leading zero bits of x (x != 0)
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inline int count_leading_zeros(std::uint64_t x) noexcept
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{
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#if defined(__GNUC__) || defined(__clang__)
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return __builtin_clzll(x);
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#elif defined(_MSC_VER) && (defined(_M_X64) || defined(_M_ARM64))
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unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan*64 takes
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_BitScanReverse64(&index, x);
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return 63 - static_cast<int>(index);
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#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_ARM))
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unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan* takes
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if (_BitScanReverse(&index, static_cast<unsigned long>(x >> 32u))) // NOLINT(runtime/int)
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{
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return 31 - static_cast<int>(index);
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}
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_BitScanReverse(&index, static_cast<unsigned long>(x)); // NOLINT(runtime/int)
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return 63 - static_cast<int>(index);
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#elif defined(__cpp_lib_bitops)
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return std::countl_zero(x);
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#else
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int n = 0;
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for (int shift = 32; shift != 0; shift >>= 1)
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{
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if ((x >> (64 - shift)) == 0)
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{
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n += shift;
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x <<= shift;
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}
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}
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return n;
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#endif
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}
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/// number of trailing zero bits of x (x != 0)
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inline int count_trailing_zeros(std::uint64_t x) noexcept
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{
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#if defined(__GNUC__) || defined(__clang__)
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return __builtin_ctzll(x);
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#elif defined(_MSC_VER) && (defined(_M_X64) || defined(_M_ARM64))
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unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan*64 takes
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_BitScanForward64(&index, x);
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return static_cast<int>(index);
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#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_ARM))
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unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan* takes
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if (_BitScanForward(&index, static_cast<unsigned long>(x))) // NOLINT(runtime/int)
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{
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return static_cast<int>(index);
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}
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_BitScanForward(&index, static_cast<unsigned long>(x >> 32u)); // NOLINT(runtime/int)
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return 32 + static_cast<int>(index);
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#elif defined(__cpp_lib_bitops)
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return std::countr_zero(x);
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#else
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int n = 0;
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for (int shift = 32; shift != 0; shift >>= 1)
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{
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if ((x << (64 - shift)) == 0)
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{
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n += shift;
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x >>= shift;
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}
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}
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return n;
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#endif
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}
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/// the object representation of @a from as a @a To (std::bit_cast in C++20)
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template<typename To, typename From>
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JSON_HEDLEY_ALWAYS_INLINE To bit_cast(const From& from) noexcept
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{
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static_assert(sizeof(To) == sizeof(From), "bit_cast needs types of the same size");
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#if defined(__cpp_lib_bit_cast)
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return std::bit_cast<To>(from);
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#else
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To to {};
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std::memcpy(&to, &from, sizeof(To));
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return to;
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#endif
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}
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/// x with its bytes in reverse order (std::byteswap in C++23); compilers lower
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/// it to a single bswap/rev/movbe
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inline std::uint16_t byteswap(std::uint16_t x) noexcept
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{
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#if defined(__GNUC__) || defined(__clang__)
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return __builtin_bswap16(x);
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#elif defined(_MSC_VER)
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return _byteswap_ushort(x);
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#elif defined(__cpp_lib_byteswap)
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return std::byteswap(x);
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#else
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return static_cast<std::uint16_t>((x >> 8u) | (x << 8u));
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#endif
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}
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/// x with its bytes in reverse order (std::byteswap in C++23)
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inline std::uint32_t byteswap(std::uint32_t x) noexcept
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{
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#if defined(__GNUC__) || defined(__clang__)
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return __builtin_bswap32(x);
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#elif defined(_MSC_VER)
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return _byteswap_ulong(x);
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#elif defined(__cpp_lib_byteswap)
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return std::byteswap(x);
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#else
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return ((x & 0x000000FFu) << 24u) | ((x & 0x0000FF00u) << 8u)
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| ((x & 0x00FF0000u) >> 8u) | ((x & 0xFF000000u) >> 24u);
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#endif
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}
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/// x with its bytes in reverse order (std::byteswap in C++23)
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inline std::uint64_t byteswap(std::uint64_t x) noexcept
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{
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#if defined(__GNUC__) || defined(__clang__)
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return __builtin_bswap64(x);
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#elif defined(_MSC_VER)
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return _byteswap_uint64(x);
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#elif defined(__cpp_lib_byteswap)
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return std::byteswap(x);
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#else
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x = ((x & 0x00000000FFFFFFFFull) << 32u) | ((x & 0xFFFFFFFF00000000ull) >> 32u);
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x = ((x & 0x0000FFFF0000FFFFull) << 16u) | ((x & 0xFFFF0000FFFF0000ull) >> 16u);
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x = ((x & 0x00FF00FF00FF00FFull) << 8u) | ((x & 0xFF00FF00FF00FF00ull) >> 8u);
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return x;
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#endif
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}
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/// the 128-bit product of two 64-bit numbers
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struct uint128_parts
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{
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std::uint64_t low;
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std::uint64_t high;
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};
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inline uint128_parts full_multiplication(std::uint64_t a, std::uint64_t b) noexcept
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{
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#if defined(__SIZEOF_INT128__)
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__extension__ using uint128 = unsigned __int128;
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const uint128 r = static_cast<uint128>(a) * b;
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return {static_cast<std::uint64_t>(r), static_cast<std::uint64_t>(r >> 64u)};
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#elif defined(_MSC_VER) && defined(_M_X64)
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std::uint64_t high = 0;
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const std::uint64_t low = _umul128(a, b, &high);
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return {low, high};
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#elif defined(_MSC_VER) && defined(_M_ARM64)
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return {a * b, __umulh(a, b)};
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#else
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const std::uint64_t a_lo = a & 0xFFFFFFFFu;
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const std::uint64_t a_hi = a >> 32u;
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const std::uint64_t b_lo = b & 0xFFFFFFFFu;
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const std::uint64_t b_hi = b >> 32u;
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const std::uint64_t lo_lo = a_lo * b_lo;
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const std::uint64_t hi_lo = a_hi * b_lo;
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const std::uint64_t lo_hi = a_lo * b_hi;
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const std::uint64_t hi_hi = a_hi * b_hi;
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const std::uint64_t cross = (lo_lo >> 32u) + (hi_lo & 0xFFFFFFFFu) + lo_hi;
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return {(cross << 32u) | (lo_lo & 0xFFFFFFFFu), (hi_lo >> 32u) + (cross >> 32u) + hi_hi};
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#endif
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}
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/// eight bytes as a little-endian word (a single load on little-endian
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/// targets; always inlined, as GCC otherwise calls it in the number loops)
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JSON_HEDLEY_ALWAYS_INLINE std::uint64_t read_eight_bytes(const unsigned char* b) noexcept
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{
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#if JSON_LITTLE_ENDIAN_TARGET
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// the byte order already matches
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std::uint64_t result = 0;
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std::memcpy(&result, b, sizeof(result));
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return result;
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#else
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return static_cast<std::uint64_t>(b[0]) | (static_cast<std::uint64_t>(b[1]) << 8u)
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| (static_cast<std::uint64_t>(b[2]) << 16u) | (static_cast<std::uint64_t>(b[3]) << 24u)
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| (static_cast<std::uint64_t>(b[4]) << 32u) | (static_cast<std::uint64_t>(b[5]) << 40u)
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| (static_cast<std::uint64_t>(b[6]) << 48u) | (static_cast<std::uint64_t>(b[7]) << 56u);
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#endif
|
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}
|
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|
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/// eight bytes as a little-endian word
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JSON_HEDLEY_ALWAYS_INLINE std::uint64_t read_eight_bytes(const char* p) noexcept
|
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{
|
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return read_eight_bytes(reinterpret_cast<const unsigned char*>(p)); // NOLINT(cppcoreguidelines-pro-type-reinterpret-cast)
|
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}
|
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|
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} // namespace detail
|
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NLOHMANN_JSON_NAMESPACE_END
|
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|
||||
// #include <nlohmann/detail/exceptions.hpp>
|
||||
|
||||
// #include <nlohmann/detail/input/input_adapters.hpp>
|
||||
@@ -10316,231 +10543,6 @@ NLOHMANN_JSON_NAMESPACE_END
|
||||
#include <vector> // vector
|
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|
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// #include <nlohmann/detail/bit_ops.hpp>
|
||||
// __ _____ _____ _____
|
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// __| | __| | | | JSON for Modern C++
|
||||
// | | |__ | | | | | | version 3.12.0
|
||||
// |_____|_____|_____|_|___| https://github.com/nlohmann/json
|
||||
//
|
||||
// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>
|
||||
// SPDX-License-Identifier: MIT
|
||||
|
||||
|
||||
|
||||
#include <cstdint> // uint64_t
|
||||
#include <cstring> // memcpy
|
||||
#if defined(_MSC_VER) && (defined(_M_X64) || defined(_M_ARM64)) && (!defined(__SIZEOF_INT128__) || (!defined(__GNUC__) && !defined(__clang__)))
|
||||
#include <intrin0.h> // __umulh, _umul128, _BitScanForward64, _BitScanReverse64
|
||||
#endif
|
||||
|
||||
#ifdef _MSC_VER
|
||||
#include <cstdlib> // _byteswap_ushort, _byteswap_ulong, _byteswap_uint64
|
||||
#endif
|
||||
#if defined(_MSC_VER) && !defined(__clang__) && (defined(_M_IX86) || defined(_M_ARM))
|
||||
#include <intrin.h> // _BitScanForward, _BitScanReverse
|
||||
#endif
|
||||
|
||||
// #include <nlohmann/detail/macro_scope.hpp>
|
||||
// JSON_HEDLEY_ALWAYS_INLINE, NLOHMANN_JSON_NAMESPACE_BEGIN
|
||||
|
||||
#if defined(__cpp_lib_bit_cast) || defined(__cpp_lib_bitops) || defined(__cpp_lib_byteswap)
|
||||
#include <bit> // bit_cast, byteswap, countl_zero, countr_zero
|
||||
#endif
|
||||
|
||||
// Portable bit-level helpers for the number and string scanners. They use
|
||||
// compiler builtins or platform-specific intrinsics where available, the
|
||||
// C++20 <bit> functions next, and plain C++ otherwise, so they work regardless
|
||||
// of byte order. (The builtins and intrinsics come first: MSVC's
|
||||
// std::countl_zero checks for LZCNT at run time unless AVX2 is enabled.)
|
||||
|
||||
NLOHMANN_JSON_NAMESPACE_BEGIN
|
||||
namespace detail
|
||||
{
|
||||
|
||||
/// number of leading zero bits of x (x != 0)
|
||||
inline int count_leading_zeros(std::uint64_t x) noexcept
|
||||
{
|
||||
#if defined(__GNUC__) || defined(__clang__)
|
||||
return __builtin_clzll(x);
|
||||
#elif defined(_MSC_VER) && (defined(_M_X64) || defined(_M_ARM64))
|
||||
unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan*64 takes
|
||||
_BitScanReverse64(&index, x);
|
||||
return 63 - static_cast<int>(index);
|
||||
#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_ARM))
|
||||
unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan* takes
|
||||
if (_BitScanReverse(&index, static_cast<unsigned long>(x >> 32u))) // NOLINT(runtime/int)
|
||||
{
|
||||
return 31 - static_cast<int>(index);
|
||||
}
|
||||
_BitScanReverse(&index, static_cast<unsigned long>(x)); // NOLINT(runtime/int)
|
||||
return 63 - static_cast<int>(index);
|
||||
#elif defined(__cpp_lib_bitops)
|
||||
return std::countl_zero(x);
|
||||
#else
|
||||
int n = 0;
|
||||
for (int shift = 32; shift != 0; shift >>= 1)
|
||||
{
|
||||
if ((x >> (64 - shift)) == 0)
|
||||
{
|
||||
n += shift;
|
||||
x <<= shift;
|
||||
}
|
||||
}
|
||||
return n;
|
||||
#endif
|
||||
}
|
||||
|
||||
/// number of trailing zero bits of x (x != 0)
|
||||
inline int count_trailing_zeros(std::uint64_t x) noexcept
|
||||
{
|
||||
#if defined(__GNUC__) || defined(__clang__)
|
||||
return __builtin_ctzll(x);
|
||||
#elif defined(_MSC_VER) && (defined(_M_X64) || defined(_M_ARM64))
|
||||
unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan*64 takes
|
||||
_BitScanForward64(&index, x);
|
||||
return static_cast<int>(index);
|
||||
#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_ARM))
|
||||
unsigned long index = 0; // NOLINT(runtime/int): the type _BitScan* takes
|
||||
if (_BitScanForward(&index, static_cast<unsigned long>(x))) // NOLINT(runtime/int)
|
||||
{
|
||||
return static_cast<int>(index);
|
||||
}
|
||||
_BitScanForward(&index, static_cast<unsigned long>(x >> 32u)); // NOLINT(runtime/int)
|
||||
return 32 + static_cast<int>(index);
|
||||
#elif defined(__cpp_lib_bitops)
|
||||
return std::countr_zero(x);
|
||||
#else
|
||||
int n = 0;
|
||||
for (int shift = 32; shift != 0; shift >>= 1)
|
||||
{
|
||||
if ((x << (64 - shift)) == 0)
|
||||
{
|
||||
n += shift;
|
||||
x >>= shift;
|
||||
}
|
||||
}
|
||||
return n;
|
||||
#endif
|
||||
}
|
||||
|
||||
/// the object representation of @a from as a @a To (std::bit_cast in C++20)
|
||||
template<typename To, typename From>
|
||||
JSON_HEDLEY_ALWAYS_INLINE To bit_cast(const From& from) noexcept
|
||||
{
|
||||
static_assert(sizeof(To) == sizeof(From), "bit_cast needs types of the same size");
|
||||
#if defined(__cpp_lib_bit_cast)
|
||||
return std::bit_cast<To>(from);
|
||||
#else
|
||||
To to {};
|
||||
std::memcpy(&to, &from, sizeof(To));
|
||||
return to;
|
||||
#endif
|
||||
}
|
||||
|
||||
/// x with its bytes in reverse order (std::byteswap in C++23); compilers lower
|
||||
/// it to a single bswap/rev/movbe
|
||||
inline std::uint16_t byteswap(std::uint16_t x) noexcept
|
||||
{
|
||||
#if defined(__GNUC__) || defined(__clang__)
|
||||
return __builtin_bswap16(x);
|
||||
#elif defined(_MSC_VER)
|
||||
return _byteswap_ushort(x);
|
||||
#elif defined(__cpp_lib_byteswap)
|
||||
return std::byteswap(x);
|
||||
#else
|
||||
return static_cast<std::uint16_t>((x >> 8u) | (x << 8u));
|
||||
#endif
|
||||
}
|
||||
|
||||
/// x with its bytes in reverse order (std::byteswap in C++23)
|
||||
inline std::uint32_t byteswap(std::uint32_t x) noexcept
|
||||
{
|
||||
#if defined(__GNUC__) || defined(__clang__)
|
||||
return __builtin_bswap32(x);
|
||||
#elif defined(_MSC_VER)
|
||||
return _byteswap_ulong(x);
|
||||
#elif defined(__cpp_lib_byteswap)
|
||||
return std::byteswap(x);
|
||||
#else
|
||||
return ((x & 0x000000FFu) << 24u) | ((x & 0x0000FF00u) << 8u)
|
||||
| ((x & 0x00FF0000u) >> 8u) | ((x & 0xFF000000u) >> 24u);
|
||||
#endif
|
||||
}
|
||||
|
||||
/// x with its bytes in reverse order (std::byteswap in C++23)
|
||||
inline std::uint64_t byteswap(std::uint64_t x) noexcept
|
||||
{
|
||||
#if defined(__GNUC__) || defined(__clang__)
|
||||
return __builtin_bswap64(x);
|
||||
#elif defined(_MSC_VER)
|
||||
return _byteswap_uint64(x);
|
||||
#elif defined(__cpp_lib_byteswap)
|
||||
return std::byteswap(x);
|
||||
#else
|
||||
x = ((x & 0x00000000FFFFFFFFull) << 32u) | ((x & 0xFFFFFFFF00000000ull) >> 32u);
|
||||
x = ((x & 0x0000FFFF0000FFFFull) << 16u) | ((x & 0xFFFF0000FFFF0000ull) >> 16u);
|
||||
x = ((x & 0x00FF00FF00FF00FFull) << 8u) | ((x & 0xFF00FF00FF00FF00ull) >> 8u);
|
||||
return x;
|
||||
#endif
|
||||
}
|
||||
|
||||
/// the 128-bit product of two 64-bit numbers
|
||||
struct uint128_parts
|
||||
{
|
||||
std::uint64_t low;
|
||||
std::uint64_t high;
|
||||
};
|
||||
|
||||
inline uint128_parts full_multiplication(std::uint64_t a, std::uint64_t b) noexcept
|
||||
{
|
||||
#if defined(__SIZEOF_INT128__)
|
||||
__extension__ using uint128 = unsigned __int128;
|
||||
const uint128 r = static_cast<uint128>(a) * b;
|
||||
return {static_cast<std::uint64_t>(r), static_cast<std::uint64_t>(r >> 64u)};
|
||||
#elif defined(_MSC_VER) && defined(_M_X64)
|
||||
std::uint64_t high = 0;
|
||||
const std::uint64_t low = _umul128(a, b, &high);
|
||||
return {low, high};
|
||||
#elif defined(_MSC_VER) && defined(_M_ARM64)
|
||||
return {a * b, __umulh(a, b)};
|
||||
#else
|
||||
const std::uint64_t a_lo = a & 0xFFFFFFFFu;
|
||||
const std::uint64_t a_hi = a >> 32u;
|
||||
const std::uint64_t b_lo = b & 0xFFFFFFFFu;
|
||||
const std::uint64_t b_hi = b >> 32u;
|
||||
const std::uint64_t lo_lo = a_lo * b_lo;
|
||||
const std::uint64_t hi_lo = a_hi * b_lo;
|
||||
const std::uint64_t lo_hi = a_lo * b_hi;
|
||||
const std::uint64_t hi_hi = a_hi * b_hi;
|
||||
const std::uint64_t cross = (lo_lo >> 32u) + (hi_lo & 0xFFFFFFFFu) + lo_hi;
|
||||
return {(cross << 32u) | (lo_lo & 0xFFFFFFFFu), (hi_lo >> 32u) + (cross >> 32u) + hi_hi};
|
||||
#endif
|
||||
}
|
||||
|
||||
/// eight bytes as a little-endian word (a single load on little-endian
|
||||
/// targets; always inlined, as GCC otherwise calls it in the number loops)
|
||||
JSON_HEDLEY_ALWAYS_INLINE std::uint64_t read_eight_bytes(const unsigned char* b) noexcept
|
||||
{
|
||||
#if JSON_LITTLE_ENDIAN_TARGET
|
||||
// the byte order already matches
|
||||
std::uint64_t result = 0;
|
||||
std::memcpy(&result, b, sizeof(result));
|
||||
return result;
|
||||
#else
|
||||
return static_cast<std::uint64_t>(b[0]) | (static_cast<std::uint64_t>(b[1]) << 8u)
|
||||
| (static_cast<std::uint64_t>(b[2]) << 16u) | (static_cast<std::uint64_t>(b[3]) << 24u)
|
||||
| (static_cast<std::uint64_t>(b[4]) << 32u) | (static_cast<std::uint64_t>(b[5]) << 40u)
|
||||
| (static_cast<std::uint64_t>(b[6]) << 48u) | (static_cast<std::uint64_t>(b[7]) << 56u);
|
||||
#endif
|
||||
}
|
||||
|
||||
/// eight bytes as a little-endian word
|
||||
JSON_HEDLEY_ALWAYS_INLINE std::uint64_t read_eight_bytes(const char* p) noexcept
|
||||
{
|
||||
return read_eight_bytes(reinterpret_cast<const unsigned char*>(p)); // NOLINT(cppcoreguidelines-pro-type-reinterpret-cast)
|
||||
}
|
||||
|
||||
} // namespace detail
|
||||
NLOHMANN_JSON_NAMESPACE_END
|
||||
|
||||
// #include <nlohmann/detail/input/input_adapters.hpp>
|
||||
|
||||
@@ -18911,16 +18913,10 @@ class binary_reader
|
||||
return get_half_float(false);
|
||||
|
||||
case 0xFA: // Single-Precision Float (four-byte IEEE 754)
|
||||
{
|
||||
float number{};
|
||||
return get_number(number) && emit_float(number);
|
||||
}
|
||||
return get_cbor_float<float>();
|
||||
|
||||
case 0xFB: // Double-Precision Float (eight-byte IEEE 754)
|
||||
{
|
||||
double number{};
|
||||
return get_number(number) && emit_float(number);
|
||||
}
|
||||
return get_cbor_float<double>();
|
||||
|
||||
default: // anything else (0xFF is handled inside the other types)
|
||||
{
|
||||
@@ -18929,6 +18925,16 @@ class binary_reader
|
||||
}
|
||||
}
|
||||
|
||||
/// read a single- or double-precision float (kept out of
|
||||
/// parse_cbor_value, which is inlined into parse_cbor_internal)
|
||||
template<typename NumberType>
|
||||
JSON_HEDLEY_NEVER_INLINE
|
||||
bool get_cbor_float()
|
||||
{
|
||||
NumberType number{};
|
||||
return get_number(number) && emit_float(number);
|
||||
}
|
||||
|
||||
/*!
|
||||
@brief reports a nested indefinite-length CBOR string or byte array
|
||||
@param[in] type_name name of the rejected string type
|
||||
@@ -21996,6 +22002,27 @@ class binary_reader
|
||||
return current;
|
||||
}
|
||||
|
||||
/// reverse the byte order of a double with a single byteswap(): GCC does
|
||||
/// not merge the byte-wise swap of the generic version into one
|
||||
static void byte_swap(double& number) noexcept
|
||||
{
|
||||
static_assert(sizeof(double) == sizeof(std::uint64_t), "double must have 64 bits");
|
||||
std::uint64_t bits{};
|
||||
std::memcpy(&bits, &number, sizeof(bits));
|
||||
bits = byteswap(bits);
|
||||
std::memcpy(&number, &bits, sizeof(bits));
|
||||
}
|
||||
|
||||
/// reverse the byte order of a float with a single byteswap()
|
||||
static void byte_swap(float& number) noexcept
|
||||
{
|
||||
static_assert(sizeof(float) == sizeof(std::uint32_t), "float must have 32 bits");
|
||||
std::uint32_t bits{};
|
||||
std::memcpy(&bits, &number, sizeof(bits));
|
||||
bits = byteswap(bits);
|
||||
std::memcpy(&number, &bits, sizeof(bits));
|
||||
}
|
||||
|
||||
template<class NumberType>
|
||||
static void byte_swap(NumberType& number)
|
||||
{
|
||||
|
||||
Reference in new issue
Block a user