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// ArduinoJson - arduinojson.org
// Copyright Benoit Blanchon 2014-2018
// MIT License
#pragma once
#include <stdint.h>
#include <stdlib.h> // for size_t
#include "../Configuration.hpp"
#include "../Polyfills/math.hpp"
namespace ArduinoJson {
namespace Internals {
template <typename T, size_t = sizeof(T)>
struct FloatTraits {};
template <typename T>
struct FloatTraits<T, 8 /*64bits*/> {
typedef int64_t mantissa_type;
static const short mantissa_bits = 52;
static const mantissa_type mantissa_max =
(static_cast<mantissa_type>(1) << mantissa_bits) - 1;
typedef int16_t exponent_type;
static const exponent_type exponent_max = 308;
template <typename TExponent>
static T make_float(T m, TExponent e) {
if (e > 0) {
for (uint8_t index = 0; e != 0; index++) {
if (e & 1) m *= positiveBinaryPowerOfTen(index);
e >>= 1;
}
} else {
e = TExponent(-e);
for (uint8_t index = 0; e != 0; index++) {
if (e & 1) m *= negativeBinaryPowerOfTen(index);
e >>= 1;
}
}
return m;
}
static T positiveBinaryPowerOfTen(int index) {
static T factors[] = {
1e1,
1e2,
1e4,
1e8,
1e16,
forge(0x4693B8B5, 0xB5056E17), // 1e32
forge(0x4D384F03, 0xE93FF9F5), // 1e64
forge(0x5A827748, 0xF9301D32), // 1e128
forge(0x75154FDD, 0x7F73BF3C) // 1e256
};
return factors[index];
}
static T negativeBinaryPowerOfTen(int index) {
static T factors[] = {
forge(0x3FB99999, 0x9999999A), // 1e-1
forge(0x3F847AE1, 0x47AE147B), // 1e-2
forge(0x3F1A36E2, 0xEB1C432D), // 1e-4
forge(0x3E45798E, 0xE2308C3A), // 1e-8
forge(0x3C9CD2B2, 0x97D889BC), // 1e-16
forge(0x3949F623, 0xD5A8A733), // 1e-32
forge(0x32A50FFD, 0x44F4A73D), // 1e-64
forge(0x255BBA08, 0xCF8C979D), // 1e-128
forge(0x0AC80628, 0x64AC6F43) // 1e-256
};
return factors[index];
}
static T negativeBinaryPowerOfTenPlusOne(int index) {
static T factors[] = {
1e0,
forge(0x3FB99999, 0x9999999A), // 1e-1
forge(0x3F50624D, 0xD2F1A9FC), // 1e-3
forge(0x3E7AD7F2, 0x9ABCAF48), // 1e-7
forge(0x3CD203AF, 0x9EE75616), // 1e-15
forge(0x398039D6, 0x65896880), // 1e-31
forge(0x32DA53FC, 0x9631D10D), // 1e-63
forge(0x25915445, 0x81B7DEC2), // 1e-127
forge(0x0AFE07B2, 0x7DD78B14) // 1e-255
};
return factors[index];
}
static T nan() {
return forge(0x7ff80000, 0x00000000);
}
static T inf() {
return forge(0x7ff00000, 0x00000000);
}
// constructs a double floating point values from its binary representation
// we use this function to workaround platforms with single precision literals
// (for example, when -fsingle-precision-constant is passed to GCC)
static T forge(uint32_t msb, uint32_t lsb) {
union {
uint64_t integerBits;
T floatBits;
};
integerBits = (uint64_t(msb) << 32) | lsb;
return floatBits;
}
};
template <typename T>
struct FloatTraits<T, 4 /*32bits*/> {
typedef int32_t mantissa_type;
static const short mantissa_bits = 23;
static const mantissa_type mantissa_max =
(static_cast<mantissa_type>(1) << mantissa_bits) - 1;
typedef int8_t exponent_type;
static const exponent_type exponent_max = 38;
template <typename TExponent>
static T make_float(T m, TExponent e) {
if (e > 0) {
for (uint8_t index = 0; e != 0; index++) {
if (e & 1) m *= positiveBinaryPowerOfTen(index);
e >>= 1;
}
} else {
e = -e;
for (uint8_t index = 0; e != 0; index++) {
if (e & 1) m *= negativeBinaryPowerOfTen(index);
e >>= 1;
}
}
return m;
}
static T positiveBinaryPowerOfTen(int index) {
static T factors[] = {1e1f, 1e2f, 1e4f, 1e8f, 1e16f, 1e32f};
return factors[index];
}
static T negativeBinaryPowerOfTen(int index) {
static T factors[] = {1e-1f, 1e-2f, 1e-4f, 1e-8f, 1e-16f, 1e-32f};
return factors[index];
}
static T negativeBinaryPowerOfTenPlusOne(int index) {
static T factors[] = {1e0f, 1e-1f, 1e-3f, 1e-7f, 1e-15f, 1e-31f};
return factors[index];
}
static T forge(uint32_t bits) {
union {
uint32_t integerBits;
T floatBits;
};
integerBits = bits;
return floatBits;
}
static T nan() {
return forge(0x7fc00000);
}
static T inf() {
return forge(0x7f800000);
}
};
}
}
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