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Merge branch 'main' into main

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Daniel Lemire 2023-05-08 16:44:35 -04:00 committed by GitHub
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5 changed files with 121 additions and 84 deletions
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3
.gitignore vendored
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@ -17,4 +17,7 @@ Release/
*.vsp
*.diagsession
*.hint
# VS CMake
/out/
/CMakeSettings.json

32
include/fast_float/fast_float.h
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@ -1,38 +1,10 @@
#ifndef FASTFLOAT_FAST_FLOAT_H
#define FASTFLOAT_FAST_FLOAT_H
#include <system_error>
#include "constexpr_feature_detect.h"
#include "float_common.h"
namespace fast_float {
enum chars_format {
scientific = 1<<0,
fixed = 1<<2,
hex = 1<<3,
general = fixed | scientific
};
template <typename UC>
struct from_chars_result_t {
UC const * ptr;
std::errc ec;
};
using from_chars_result = from_chars_result_t<char>;
template <typename UC>
struct parse_options_t {
constexpr explicit parse_options_t(chars_format fmt = chars_format::general,
UC dot = UC('.'))
: format(fmt), decimal_point(dot) {}
/** Which number formats are accepted */
chars_format format;
/** The character used as decimal point */
UC decimal_point;
};
using parse_options = parse_options_t<char>;
/**
* This function parses the character sequence [first,last) for a number. It parses floating-point numbers expecting
* a locale-indepent format equivalent to what is used by std::strtod in the default ("C") locale.

159
include/fast_float/float_common.h
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@ -6,6 +6,40 @@
#include <cassert>
#include <cstring>
#include <type_traits>
#include <system_error>
#include "constexpr_feature_detect.h"
namespace fast_float {
enum chars_format {
scientific = 1 << 0,
fixed = 1 << 2,
hex = 1 << 3,
general = fixed | scientific
};
template <typename UC>
struct from_chars_result_t {
UC const* ptr;
std::errc ec;
};
using from_chars_result = from_chars_result_t<char>;
template <typename UC>
struct parse_options_t {
constexpr explicit parse_options_t(chars_format fmt = chars_format::general,
UC dot = UC('.'))
: format(fmt), decimal_point(dot) {}
/** Which number formats are accepted */
chars_format format;
/** The character used as decimal point */
UC decimal_point;
};
using parse_options = parse_options_t<char>;
}
#if FASTFLOAT_HAS_BIT_CAST
#include <bit>
@ -291,16 +325,43 @@ struct adjusted_mantissa {
// Bias so we can get the real exponent with an invalid adjusted_mantissa.
constexpr static int32_t invalid_am_bias = -0x8000;
constexpr static double powers_of_ten_double[] = {
1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11,
1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};
constexpr static float powers_of_ten_float[] = {1e0f, 1e1f, 1e2f, 1e3f, 1e4f, 1e5f,
1e6f, 1e7f, 1e8f, 1e9f, 1e10f};
// used for max_mantissa_double and max_mantissa_float
// used for binary_format_lookup_tables<T>::max_mantissa
constexpr uint64_t constant_55555 = 5 * 5 * 5 * 5 * 5;
// Largest integer value v so that (5**index * v) <= 1<<53.
// 0x10000000000000 == 1 << 53
constexpr static uint64_t max_mantissa_double[] = {
template <typename T, typename U = void>
struct binary_format_lookup_tables;
template <typename T> struct binary_format : binary_format_lookup_tables<T> {
using equiv_uint = typename std::conditional<sizeof(T) == 4, uint32_t, uint64_t>::type;
static inline constexpr int mantissa_explicit_bits();
static inline constexpr int minimum_exponent();
static inline constexpr int infinite_power();
static inline constexpr int sign_index();
static inline constexpr int min_exponent_fast_path(); // used when fegetround() == FE_TONEAREST
static inline constexpr int max_exponent_fast_path();
static inline constexpr int max_exponent_round_to_even();
static inline constexpr int min_exponent_round_to_even();
static inline constexpr uint64_t max_mantissa_fast_path(int64_t power);
static inline constexpr uint64_t max_mantissa_fast_path(); // used when fegetround() == FE_TONEAREST
static inline constexpr int largest_power_of_ten();
static inline constexpr int smallest_power_of_ten();
static inline constexpr T exact_power_of_ten(int64_t power);
static inline constexpr size_t max_digits();
static inline constexpr equiv_uint exponent_mask();
static inline constexpr equiv_uint mantissa_mask();
static inline constexpr equiv_uint hidden_bit_mask();
};
template <typename U>
struct binary_format_lookup_tables<double, U> {
static constexpr double powers_of_ten[] = {
1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, 1e10, 1e11,
1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};
// Largest integer value v so that (5**index * v) <= 1<<53.
// 0x10000000000000 == 1 << 53
static constexpr uint64_t max_mantissa[] = {
0x10000000000000,
0x10000000000000 / 5,
0x10000000000000 / (5 * 5),
@ -325,44 +386,42 @@ constexpr static uint64_t max_mantissa_double[] = {
0x10000000000000 / (constant_55555 * constant_55555 * constant_55555 * constant_55555 * 5 * 5),
0x10000000000000 / (constant_55555 * constant_55555 * constant_55555 * constant_55555 * 5 * 5 * 5),
0x10000000000000 / (constant_55555 * constant_55555 * constant_55555 * constant_55555 * 5 * 5 * 5 * 5)};
};
template <typename U>
constexpr double binary_format_lookup_tables<double, U>::powers_of_ten[];
template <typename U>
constexpr uint64_t binary_format_lookup_tables<double, U>::max_mantissa[];
template <typename U>
struct binary_format_lookup_tables<float, U> {
static constexpr float powers_of_ten[] = {1e0f, 1e1f, 1e2f, 1e3f, 1e4f, 1e5f,
1e6f, 1e7f, 1e8f, 1e9f, 1e10f};
// Largest integer value v so that (5**index * v) <= 1<<24.
// 0x1000000 == 1<<24
constexpr static uint64_t max_mantissa_float[] = {
0x1000000,
0x1000000 / 5,
0x1000000 / (5 * 5),
0x1000000 / (5 * 5 * 5),
0x1000000 / (5 * 5 * 5 * 5),
0x1000000 / (constant_55555),
0x1000000 / (constant_55555 * 5),
0x1000000 / (constant_55555 * 5 * 5),
0x1000000 / (constant_55555 * 5 * 5 * 5),
0x1000000 / (constant_55555 * 5 * 5 * 5 * 5),
0x1000000 / (constant_55555 * constant_55555),
0x1000000 / (constant_55555 * constant_55555 * 5)};
template <typename T> struct binary_format {
using equiv_uint = typename std::conditional<sizeof(T) == 4, uint32_t, uint64_t>::type;
static inline constexpr int mantissa_explicit_bits();
static inline constexpr int minimum_exponent();
static inline constexpr int infinite_power();
static inline constexpr int sign_index();
static inline constexpr int min_exponent_fast_path(); // used when fegetround() == FE_TONEAREST
static inline constexpr int max_exponent_fast_path();
static inline constexpr int max_exponent_round_to_even();
static inline constexpr int min_exponent_round_to_even();
static inline constexpr uint64_t max_mantissa_fast_path(int64_t power);
static inline constexpr uint64_t max_mantissa_fast_path(); // used when fegetround() == FE_TONEAREST
static inline constexpr int largest_power_of_ten();
static inline constexpr int smallest_power_of_ten();
static inline constexpr T exact_power_of_ten(int64_t power);
static inline constexpr size_t max_digits();
static inline constexpr equiv_uint exponent_mask();
static inline constexpr equiv_uint mantissa_mask();
static inline constexpr equiv_uint hidden_bit_mask();
static constexpr uint64_t max_mantissa[] = {
0x1000000,
0x1000000 / 5,
0x1000000 / (5 * 5),
0x1000000 / (5 * 5 * 5),
0x1000000 / (5 * 5 * 5 * 5),
0x1000000 / (constant_55555),
0x1000000 / (constant_55555 * 5),
0x1000000 / (constant_55555 * 5 * 5),
0x1000000 / (constant_55555 * 5 * 5 * 5),
0x1000000 / (constant_55555 * 5 * 5 * 5 * 5),
0x1000000 / (constant_55555 * constant_55555),
0x1000000 / (constant_55555 * constant_55555 * 5)};
};
template <typename U>
constexpr float binary_format_lookup_tables<float, U>::powers_of_ten[];
template <typename U>
constexpr uint64_t binary_format_lookup_tables<float, U>::max_mantissa[];
template <> inline constexpr int binary_format<double>::min_exponent_fast_path() {
#if (FLT_EVAL_METHOD != 1) && (FLT_EVAL_METHOD != 0)
return 0;
@ -425,6 +484,7 @@ template <> inline constexpr int binary_format<double>::max_exponent_fast_path()
template <> inline constexpr int binary_format<float>::max_exponent_fast_path() {
return 10;
}
template <> inline constexpr uint64_t binary_format<double>::max_mantissa_fast_path() {
return uint64_t(2) << mantissa_explicit_bits();
}
@ -432,7 +492,8 @@ template <> inline constexpr uint64_t binary_format<double>::max_mantissa_fast_p
// caller is responsible to ensure that
// power >= 0 && power <= 22
//
return max_mantissa_double[power];
// Work around clang bug https://godbolt.org/z/zedh7rrhc
return (void)max_mantissa[0], max_mantissa[power];
}
template <> inline constexpr uint64_t binary_format<float>::max_mantissa_fast_path() {
return uint64_t(2) << mantissa_explicit_bits();
@ -441,17 +502,19 @@ template <> inline constexpr uint64_t binary_format<float>::max_mantissa_fast_pa
// caller is responsible to ensure that
// power >= 0 && power <= 10
//
return max_mantissa_float[power];
// Work around clang bug https://godbolt.org/z/zedh7rrhc
return (void)max_mantissa[0], max_mantissa[power];
}
template <>
inline constexpr double binary_format<double>::exact_power_of_ten(int64_t power) {
return powers_of_ten_double[power];
// Work around clang bug https://godbolt.org/z/zedh7rrhc
return (void)powers_of_ten[0], powers_of_ten[power];
}
template <>
inline constexpr float binary_format<float>::exact_power_of_ten(int64_t power) {
return powers_of_ten_float[power];
// Work around clang bug https://godbolt.org/z/zedh7rrhc
return (void)powers_of_ten[0], powers_of_ten[power];
}

1
include/fast_float/parse_number.h
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@ -4,6 +4,7 @@
#include "ascii_number.h"
#include "decimal_to_binary.h"
#include "digit_comparison.h"
#include "float_common.h"
#include <cmath>
#include <cstring>

10
script/amalgamate.py
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@ -31,9 +31,8 @@ for filename in ['LICENSE-MIT', 'LICENSE-APACHE']:
processed_files[filename] = text
# code
for filename in [ 'constexpr_feature_detect.h', 'fast_float.h', 'float_common.h', 'ascii_number.h',
'fast_table.h', 'decimal_to_binary.h', 'bigint.h',
'ascii_number.h', 'digit_comparison.h', 'parse_number.h']:
for filename in [ 'constexpr_feature_detect.h', 'float_common.h', 'fast_float.h', 'ascii_number.h',
'fast_table.h', 'decimal_to_binary.h', 'bigint.h', 'digit_comparison.h', 'parse_number.h']:
with open('include/fast_float/' + filename, encoding='utf8') as f:
text = ''
for line in f:
@ -76,11 +75,10 @@ text = ''.join([
processed_files['AUTHORS'], processed_files['CONTRIBUTORS'],
*license_content(args.license),
processed_files['constexpr_feature_detect.h'],
processed_files['fast_float.h'], processed_files['float_common.h'],
processed_files['float_common.h'], processed_files['fast_float.h'],
processed_files['ascii_number.h'], processed_files['fast_table.h'],
processed_files['decimal_to_binary.h'], processed_files['bigint.h'],
processed_files['ascii_number.h'], processed_files['digit_comparison.h'],
processed_files['parse_number.h']])
processed_files['digit_comparison.h'], processed_files['parse_number.h']])
if args.output:
with open(args.output, 'wt', encoding='utf8') as f: