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Diffstat (limited to 'third_party/abseil_cpp/absl/strings/numbers.h')
| -rw-r--r-- | third_party/abseil_cpp/absl/strings/numbers.h | 273 |
1 files changed, 0 insertions, 273 deletions
diff --git a/third_party/abseil_cpp/absl/strings/numbers.h b/third_party/abseil_cpp/absl/strings/numbers.h deleted file mode 100644 index 2e004b44f887..000000000000 --- a/third_party/abseil_cpp/absl/strings/numbers.h +++ /dev/null @@ -1,273 +0,0 @@ -// -// Copyright 2017 The Abseil Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// https://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. -// -// ----------------------------------------------------------------------------- -// File: numbers.h -// ----------------------------------------------------------------------------- -// -// This package contains functions for converting strings to numbers. For -// converting numbers to strings, use `StrCat()` or `StrAppend()` in str_cat.h, -// which automatically detect and convert most number values appropriately. - -#ifndef ABSL_STRINGS_NUMBERS_H_ -#define ABSL_STRINGS_NUMBERS_H_ - -#ifdef __SSE4_2__ -#include <x86intrin.h> -#endif - -#include <cstddef> -#include <cstdlib> -#include <cstring> -#include <ctime> -#include <limits> -#include <string> -#include <type_traits> - -#include "absl/base/config.h" -#include "absl/base/internal/bits.h" -#ifdef __SSE4_2__ -// TODO(jorg): Remove this when we figure out the right way -// to swap bytes on SSE 4.2 that works with the compilers -// we claim to support. Also, add tests for the compiler -// that doesn't support the Intel _bswap64 intrinsic but -// does support all the SSE 4.2 intrinsics -#include "absl/base/internal/endian.h" -#endif -#include "absl/base/macros.h" -#include "absl/base/port.h" -#include "absl/numeric/int128.h" -#include "absl/strings/string_view.h" - -namespace absl { -ABSL_NAMESPACE_BEGIN - -// SimpleAtoi() -// -// Converts the given string (optionally followed or preceded by ASCII -// whitespace) into an integer value, returning `true` if successful. The string -// must reflect a base-10 integer whose value falls within the range of the -// integer type (optionally preceded by a `+` or `-`). If any errors are -// encountered, this function returns `false`, leaving `out` in an unspecified -// state. -template <typename int_type> -ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str, int_type* out); - -// SimpleAtof() -// -// Converts the given string (optionally followed or preceded by ASCII -// whitespace) into a float, which may be rounded on overflow or underflow, -// returning `true` if successful. -// See https://en.cppreference.com/w/c/string/byte/strtof for details about the -// allowed formats for `str`, except SimpleAtof() is locale-independent and will -// always use the "C" locale. If any errors are encountered, this function -// returns `false`, leaving `out` in an unspecified state. -ABSL_MUST_USE_RESULT bool SimpleAtof(absl::string_view str, float* out); - -// SimpleAtod() -// -// Converts the given string (optionally followed or preceded by ASCII -// whitespace) into a double, which may be rounded on overflow or underflow, -// returning `true` if successful. -// See https://en.cppreference.com/w/c/string/byte/strtof for details about the -// allowed formats for `str`, except SimpleAtod is locale-independent and will -// always use the "C" locale. If any errors are encountered, this function -// returns `false`, leaving `out` in an unspecified state. -ABSL_MUST_USE_RESULT bool SimpleAtod(absl::string_view str, double* out); - -// SimpleAtob() -// -// Converts the given string into a boolean, returning `true` if successful. -// The following case-insensitive strings are interpreted as boolean `true`: -// "true", "t", "yes", "y", "1". The following case-insensitive strings -// are interpreted as boolean `false`: "false", "f", "no", "n", "0". If any -// errors are encountered, this function returns `false`, leaving `out` in an -// unspecified state. -ABSL_MUST_USE_RESULT bool SimpleAtob(absl::string_view str, bool* out); - -ABSL_NAMESPACE_END -} // namespace absl - -// End of public API. Implementation details follow. - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace numbers_internal { - -// Digit conversion. -ABSL_DLL extern const char kHexChar[17]; // 0123456789abcdef -ABSL_DLL extern const char - kHexTable[513]; // 000102030405060708090a0b0c0d0e0f1011... -ABSL_DLL extern const char - two_ASCII_digits[100][2]; // 00, 01, 02, 03... - -// Writes a two-character representation of 'i' to 'buf'. 'i' must be in the -// range 0 <= i < 100, and buf must have space for two characters. Example: -// char buf[2]; -// PutTwoDigits(42, buf); -// // buf[0] == '4' -// // buf[1] == '2' -inline void PutTwoDigits(size_t i, char* buf) { - assert(i < 100); - memcpy(buf, two_ASCII_digits[i], 2); -} - -// safe_strto?() functions for implementing SimpleAtoi() -bool safe_strto32_base(absl::string_view text, int32_t* value, int base); -bool safe_strto64_base(absl::string_view text, int64_t* value, int base); -bool safe_strto128_base(absl::string_view text, absl::int128* value, - int base); -bool safe_strtou32_base(absl::string_view text, uint32_t* value, int base); -bool safe_strtou64_base(absl::string_view text, uint64_t* value, int base); -bool safe_strtou128_base(absl::string_view text, absl::uint128* value, - int base); - -static const int kFastToBufferSize = 32; -static const int kSixDigitsToBufferSize = 16; - -// Helper function for fast formatting of floating-point values. -// The result is the same as printf's "%g", a.k.a. "%.6g"; that is, six -// significant digits are returned, trailing zeros are removed, and numbers -// outside the range 0.0001-999999 are output using scientific notation -// (1.23456e+06). This routine is heavily optimized. -// Required buffer size is `kSixDigitsToBufferSize`. -size_t SixDigitsToBuffer(double d, char* buffer); - -// These functions are intended for speed. All functions take an output buffer -// as an argument and return a pointer to the last byte they wrote, which is the -// terminating '\0'. At most `kFastToBufferSize` bytes are written. -char* FastIntToBuffer(int32_t, char*); -char* FastIntToBuffer(uint32_t, char*); -char* FastIntToBuffer(int64_t, char*); -char* FastIntToBuffer(uint64_t, char*); - -// For enums and integer types that are not an exact match for the types above, -// use templates to call the appropriate one of the four overloads above. -template <typename int_type> -char* FastIntToBuffer(int_type i, char* buffer) { - static_assert(sizeof(i) <= 64 / 8, - "FastIntToBuffer works only with 64-bit-or-less integers."); - // TODO(jorg): This signed-ness check is used because it works correctly - // with enums, and it also serves to check that int_type is not a pointer. - // If one day something like std::is_signed<enum E> works, switch to it. - if (static_cast<int_type>(1) - 2 < 0) { // Signed - if (sizeof(i) > 32 / 8) { // 33-bit to 64-bit - return FastIntToBuffer(static_cast<int64_t>(i), buffer); - } else { // 32-bit or less - return FastIntToBuffer(static_cast<int32_t>(i), buffer); - } - } else { // Unsigned - if (sizeof(i) > 32 / 8) { // 33-bit to 64-bit - return FastIntToBuffer(static_cast<uint64_t>(i), buffer); - } else { // 32-bit or less - return FastIntToBuffer(static_cast<uint32_t>(i), buffer); - } - } -} - -// Implementation of SimpleAtoi, generalized to support arbitrary base (used -// with base different from 10 elsewhere in Abseil implementation). -template <typename int_type> -ABSL_MUST_USE_RESULT bool safe_strtoi_base(absl::string_view s, int_type* out, - int base) { - static_assert(sizeof(*out) == 4 || sizeof(*out) == 8, - "SimpleAtoi works only with 32-bit or 64-bit integers."); - static_assert(!std::is_floating_point<int_type>::value, - "Use SimpleAtof or SimpleAtod instead."); - bool parsed; - // TODO(jorg): This signed-ness check is used because it works correctly - // with enums, and it also serves to check that int_type is not a pointer. - // If one day something like std::is_signed<enum E> works, switch to it. - if (static_cast<int_type>(1) - 2 < 0) { // Signed - if (sizeof(*out) == 64 / 8) { // 64-bit - int64_t val; - parsed = numbers_internal::safe_strto64_base(s, &val, base); - *out = static_cast<int_type>(val); - } else { // 32-bit - int32_t val; - parsed = numbers_internal::safe_strto32_base(s, &val, base); - *out = static_cast<int_type>(val); - } - } else { // Unsigned - if (sizeof(*out) == 64 / 8) { // 64-bit - uint64_t val; - parsed = numbers_internal::safe_strtou64_base(s, &val, base); - *out = static_cast<int_type>(val); - } else { // 32-bit - uint32_t val; - parsed = numbers_internal::safe_strtou32_base(s, &val, base); - *out = static_cast<int_type>(val); - } - } - return parsed; -} - -// FastHexToBufferZeroPad16() -// -// Outputs `val` into `out` as if by `snprintf(out, 17, "%016x", val)` but -// without the terminating null character. Thus `out` must be of length >= 16. -// Returns the number of non-pad digits of the output (it can never be zero -// since 0 has one digit). -inline size_t FastHexToBufferZeroPad16(uint64_t val, char* out) { -#ifdef __SSE4_2__ - uint64_t be = absl::big_endian::FromHost64(val); - const auto kNibbleMask = _mm_set1_epi8(0xf); - const auto kHexDigits = _mm_setr_epi8('0', '1', '2', '3', '4', '5', '6', '7', - '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'); - auto v = _mm_loadl_epi64(reinterpret_cast<__m128i*>(&be)); // load lo dword - auto v4 = _mm_srli_epi64(v, 4); // shift 4 right - auto il = _mm_unpacklo_epi8(v4, v); // interleave bytes - auto m = _mm_and_si128(il, kNibbleMask); // mask out nibbles - auto hexchars = _mm_shuffle_epi8(kHexDigits, m); // hex chars - _mm_storeu_si128(reinterpret_cast<__m128i*>(out), hexchars); -#else - for (int i = 0; i < 8; ++i) { - auto byte = (val >> (56 - 8 * i)) & 0xFF; - auto* hex = &absl::numbers_internal::kHexTable[byte * 2]; - std::memcpy(out + 2 * i, hex, 2); - } -#endif - // | 0x1 so that even 0 has 1 digit. - return 16 - absl::base_internal::CountLeadingZeros64(val | 0x1) / 4; -} - -} // namespace numbers_internal - -// SimpleAtoi() -// -// Converts a string to an integer, using `safe_strto?()` functions for actual -// parsing, returning `true` if successful. The `safe_strto?()` functions apply -// strict checking; the string must be a base-10 integer, optionally followed or -// preceded by ASCII whitespace, with a value in the range of the corresponding -// integer type. -template <typename int_type> -ABSL_MUST_USE_RESULT bool SimpleAtoi(absl::string_view str, int_type* out) { - return numbers_internal::safe_strtoi_base(str, out, 10); -} - -ABSL_MUST_USE_RESULT inline bool SimpleAtoi(absl::string_view str, - absl::int128* out) { - return numbers_internal::safe_strto128_base(str, out, 10); -} - -ABSL_MUST_USE_RESULT inline bool SimpleAtoi(absl::string_view str, - absl::uint128* out) { - return numbers_internal::safe_strtou128_base(str, out, 10); -} - -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_STRINGS_NUMBERS_H_ |