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-rw-r--r--third_party/abseil_cpp/absl/strings/numbers.cc1083
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diff --git a/third_party/abseil_cpp/absl/strings/numbers.cc b/third_party/abseil_cpp/absl/strings/numbers.cc
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--- a/third_party/abseil_cpp/absl/strings/numbers.cc
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@@ -1,1083 +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.
-
-// This file contains string processing functions related to
-// numeric values.
-
-#include "absl/strings/numbers.h"
-
-#include <algorithm>
-#include <cassert>
-#include <cfloat>  // for DBL_DIG and FLT_DIG
-#include <cmath>   // for HUGE_VAL
-#include <cstdint>
-#include <cstdio>
-#include <cstdlib>
-#include <cstring>
-#include <iterator>
-#include <limits>
-#include <memory>
-#include <utility>
-
-#include "absl/base/attributes.h"
-#include "absl/base/internal/bits.h"
-#include "absl/base/internal/raw_logging.h"
-#include "absl/strings/ascii.h"
-#include "absl/strings/charconv.h"
-#include "absl/strings/escaping.h"
-#include "absl/strings/internal/memutil.h"
-#include "absl/strings/match.h"
-#include "absl/strings/str_cat.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-
-bool SimpleAtof(absl::string_view str, float* out) {
-  *out = 0.0;
-  str = StripAsciiWhitespace(str);
-  if (!str.empty() && str[0] == '+') {
-    str.remove_prefix(1);
-  }
-  auto result = absl::from_chars(str.data(), str.data() + str.size(), *out);
-  if (result.ec == std::errc::invalid_argument) {
-    return false;
-  }
-  if (result.ptr != str.data() + str.size()) {
-    // not all non-whitespace characters consumed
-    return false;
-  }
-  // from_chars() with DR 3081's current wording will return max() on
-  // overflow.  SimpleAtof returns infinity instead.
-  if (result.ec == std::errc::result_out_of_range) {
-    if (*out > 1.0) {
-      *out = std::numeric_limits<float>::infinity();
-    } else if (*out < -1.0) {
-      *out = -std::numeric_limits<float>::infinity();
-    }
-  }
-  return true;
-}
-
-bool SimpleAtod(absl::string_view str, double* out) {
-  *out = 0.0;
-  str = StripAsciiWhitespace(str);
-  if (!str.empty() && str[0] == '+') {
-    str.remove_prefix(1);
-  }
-  auto result = absl::from_chars(str.data(), str.data() + str.size(), *out);
-  if (result.ec == std::errc::invalid_argument) {
-    return false;
-  }
-  if (result.ptr != str.data() + str.size()) {
-    // not all non-whitespace characters consumed
-    return false;
-  }
-  // from_chars() with DR 3081's current wording will return max() on
-  // overflow.  SimpleAtod returns infinity instead.
-  if (result.ec == std::errc::result_out_of_range) {
-    if (*out > 1.0) {
-      *out = std::numeric_limits<double>::infinity();
-    } else if (*out < -1.0) {
-      *out = -std::numeric_limits<double>::infinity();
-    }
-  }
-  return true;
-}
-
-bool SimpleAtob(absl::string_view str, bool* out) {
-  ABSL_RAW_CHECK(out != nullptr, "Output pointer must not be nullptr.");
-  if (EqualsIgnoreCase(str, "true") || EqualsIgnoreCase(str, "t") ||
-      EqualsIgnoreCase(str, "yes") || EqualsIgnoreCase(str, "y") ||
-      EqualsIgnoreCase(str, "1")) {
-    *out = true;
-    return true;
-  }
-  if (EqualsIgnoreCase(str, "false") || EqualsIgnoreCase(str, "f") ||
-      EqualsIgnoreCase(str, "no") || EqualsIgnoreCase(str, "n") ||
-      EqualsIgnoreCase(str, "0")) {
-    *out = false;
-    return true;
-  }
-  return false;
-}
-
-// ----------------------------------------------------------------------
-// FastIntToBuffer() overloads
-//
-// Like the Fast*ToBuffer() functions above, these are intended for speed.
-// Unlike the Fast*ToBuffer() functions, however, these functions write
-// their output to the beginning of the buffer.  The caller is responsible
-// for ensuring that the buffer has enough space to hold the output.
-//
-// Returns a pointer to the end of the string (i.e. the null character
-// terminating the string).
-// ----------------------------------------------------------------------
-
-namespace {
-
-// Used to optimize printing a decimal number's final digit.
-const char one_ASCII_final_digits[10][2] {
-  {'0', 0}, {'1', 0}, {'2', 0}, {'3', 0}, {'4', 0},
-  {'5', 0}, {'6', 0}, {'7', 0}, {'8', 0}, {'9', 0},
-};
-
-}  // namespace
-
-char* numbers_internal::FastIntToBuffer(uint32_t i, char* buffer) {
-  uint32_t digits;
-  // The idea of this implementation is to trim the number of divides to as few
-  // as possible, and also reducing memory stores and branches, by going in
-  // steps of two digits at a time rather than one whenever possible.
-  // The huge-number case is first, in the hopes that the compiler will output
-  // that case in one branch-free block of code, and only output conditional
-  // branches into it from below.
-  if (i >= 1000000000) {     // >= 1,000,000,000
-    digits = i / 100000000;  //      100,000,000
-    i -= digits * 100000000;
-    PutTwoDigits(digits, buffer);
-    buffer += 2;
-  lt100_000_000:
-    digits = i / 1000000;  // 1,000,000
-    i -= digits * 1000000;
-    PutTwoDigits(digits, buffer);
-    buffer += 2;
-  lt1_000_000:
-    digits = i / 10000;  // 10,000
-    i -= digits * 10000;
-    PutTwoDigits(digits, buffer);
-    buffer += 2;
-  lt10_000:
-    digits = i / 100;
-    i -= digits * 100;
-    PutTwoDigits(digits, buffer);
-    buffer += 2;
- lt100:
-    digits = i;
-    PutTwoDigits(digits, buffer);
-    buffer += 2;
-    *buffer = 0;
-    return buffer;
-  }
-
-  if (i < 100) {
-    digits = i;
-    if (i >= 10) goto lt100;
-    memcpy(buffer, one_ASCII_final_digits[i], 2);
-    return buffer + 1;
-  }
-  if (i < 10000) {  //    10,000
-    if (i >= 1000) goto lt10_000;
-    digits = i / 100;
-    i -= digits * 100;
-    *buffer++ = '0' + digits;
-    goto lt100;
-  }
-  if (i < 1000000) {  //    1,000,000
-    if (i >= 100000) goto lt1_000_000;
-    digits = i / 10000;  //    10,000
-    i -= digits * 10000;
-    *buffer++ = '0' + digits;
-    goto lt10_000;
-  }
-  if (i < 100000000) {  //    100,000,000
-    if (i >= 10000000) goto lt100_000_000;
-    digits = i / 1000000;  //   1,000,000
-    i -= digits * 1000000;
-    *buffer++ = '0' + digits;
-    goto lt1_000_000;
-  }
-  // we already know that i < 1,000,000,000
-  digits = i / 100000000;  //   100,000,000
-  i -= digits * 100000000;
-  *buffer++ = '0' + digits;
-  goto lt100_000_000;
-}
-
-char* numbers_internal::FastIntToBuffer(int32_t i, char* buffer) {
-  uint32_t u = i;
-  if (i < 0) {
-    *buffer++ = '-';
-    // We need to do the negation in modular (i.e., "unsigned")
-    // arithmetic; MSVC++ apprently warns for plain "-u", so
-    // we write the equivalent expression "0 - u" instead.
-    u = 0 - u;
-  }
-  return numbers_internal::FastIntToBuffer(u, buffer);
-}
-
-char* numbers_internal::FastIntToBuffer(uint64_t i, char* buffer) {
-  uint32_t u32 = static_cast<uint32_t>(i);
-  if (u32 == i) return numbers_internal::FastIntToBuffer(u32, buffer);
-
-  // Here we know i has at least 10 decimal digits.
-  uint64_t top_1to11 = i / 1000000000;
-  u32 = static_cast<uint32_t>(i - top_1to11 * 1000000000);
-  uint32_t top_1to11_32 = static_cast<uint32_t>(top_1to11);
-
-  if (top_1to11_32 == top_1to11) {
-    buffer = numbers_internal::FastIntToBuffer(top_1to11_32, buffer);
-  } else {
-    // top_1to11 has more than 32 bits too; print it in two steps.
-    uint32_t top_8to9 = static_cast<uint32_t>(top_1to11 / 100);
-    uint32_t mid_2 = static_cast<uint32_t>(top_1to11 - top_8to9 * 100);
-    buffer = numbers_internal::FastIntToBuffer(top_8to9, buffer);
-    PutTwoDigits(mid_2, buffer);
-    buffer += 2;
-  }
-
-  // We have only 9 digits now, again the maximum uint32_t can handle fully.
-  uint32_t digits = u32 / 10000000;  // 10,000,000
-  u32 -= digits * 10000000;
-  PutTwoDigits(digits, buffer);
-  buffer += 2;
-  digits = u32 / 100000;  // 100,000
-  u32 -= digits * 100000;
-  PutTwoDigits(digits, buffer);
-  buffer += 2;
-  digits = u32 / 1000;  // 1,000
-  u32 -= digits * 1000;
-  PutTwoDigits(digits, buffer);
-  buffer += 2;
-  digits = u32 / 10;
-  u32 -= digits * 10;
-  PutTwoDigits(digits, buffer);
-  buffer += 2;
-  memcpy(buffer, one_ASCII_final_digits[u32], 2);
-  return buffer + 1;
-}
-
-char* numbers_internal::FastIntToBuffer(int64_t i, char* buffer) {
-  uint64_t u = i;
-  if (i < 0) {
-    *buffer++ = '-';
-    u = 0 - u;
-  }
-  return numbers_internal::FastIntToBuffer(u, buffer);
-}
-
-// Given a 128-bit number expressed as a pair of uint64_t, high half first,
-// return that number multiplied by the given 32-bit value.  If the result is
-// too large to fit in a 128-bit number, divide it by 2 until it fits.
-static std::pair<uint64_t, uint64_t> Mul32(std::pair<uint64_t, uint64_t> num,
-                                           uint32_t mul) {
-  uint64_t bits0_31 = num.second & 0xFFFFFFFF;
-  uint64_t bits32_63 = num.second >> 32;
-  uint64_t bits64_95 = num.first & 0xFFFFFFFF;
-  uint64_t bits96_127 = num.first >> 32;
-
-  // The picture so far: each of these 64-bit values has only the lower 32 bits
-  // filled in.
-  // bits96_127:          [ 00000000 xxxxxxxx ]
-  // bits64_95:                    [ 00000000 xxxxxxxx ]
-  // bits32_63:                             [ 00000000 xxxxxxxx ]
-  // bits0_31:                                       [ 00000000 xxxxxxxx ]
-
-  bits0_31 *= mul;
-  bits32_63 *= mul;
-  bits64_95 *= mul;
-  bits96_127 *= mul;
-
-  // Now the top halves may also have value, though all 64 of their bits will
-  // never be set at the same time, since they are a result of a 32x32 bit
-  // multiply.  This makes the carry calculation slightly easier.
-  // bits96_127:          [ mmmmmmmm | mmmmmmmm ]
-  // bits64_95:                    [ | mmmmmmmm mmmmmmmm | ]
-  // bits32_63:                      |        [ mmmmmmmm | mmmmmmmm ]
-  // bits0_31:                       |                 [ | mmmmmmmm mmmmmmmm ]
-  // eventually:        [ bits128_up | ...bits64_127.... | ..bits0_63... ]
-
-  uint64_t bits0_63 = bits0_31 + (bits32_63 << 32);
-  uint64_t bits64_127 = bits64_95 + (bits96_127 << 32) + (bits32_63 >> 32) +
-                        (bits0_63 < bits0_31);
-  uint64_t bits128_up = (bits96_127 >> 32) + (bits64_127 < bits64_95);
-  if (bits128_up == 0) return {bits64_127, bits0_63};
-
-  int shift = 64 - base_internal::CountLeadingZeros64(bits128_up);
-  uint64_t lo = (bits0_63 >> shift) + (bits64_127 << (64 - shift));
-  uint64_t hi = (bits64_127 >> shift) + (bits128_up << (64 - shift));
-  return {hi, lo};
-}
-
-// Compute num * 5 ^ expfive, and return the first 128 bits of the result,
-// where the first bit is always a one.  So PowFive(1, 0) starts 0b100000,
-// PowFive(1, 1) starts 0b101000, PowFive(1, 2) starts 0b110010, etc.
-static std::pair<uint64_t, uint64_t> PowFive(uint64_t num, int expfive) {
-  std::pair<uint64_t, uint64_t> result = {num, 0};
-  while (expfive >= 13) {
-    // 5^13 is the highest power of five that will fit in a 32-bit integer.
-    result = Mul32(result, 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5);
-    expfive -= 13;
-  }
-  constexpr int powers_of_five[13] = {
-      1,
-      5,
-      5 * 5,
-      5 * 5 * 5,
-      5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5,
-      5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5 * 5};
-  result = Mul32(result, powers_of_five[expfive & 15]);
-  int shift = base_internal::CountLeadingZeros64(result.first);
-  if (shift != 0) {
-    result.first = (result.first << shift) + (result.second >> (64 - shift));
-    result.second = (result.second << shift);
-  }
-  return result;
-}
-
-struct ExpDigits {
-  int32_t exponent;
-  char digits[6];
-};
-
-// SplitToSix converts value, a positive double-precision floating-point number,
-// into a base-10 exponent and 6 ASCII digits, where the first digit is never
-// zero.  For example, SplitToSix(1) returns an exponent of zero and a digits
-// array of {'1', '0', '0', '0', '0', '0'}.  If value is exactly halfway between
-// two possible representations, e.g. value = 100000.5, then "round to even" is
-// performed.
-static ExpDigits SplitToSix(const double value) {
-  ExpDigits exp_dig;
-  int exp = 5;
-  double d = value;
-  // First step: calculate a close approximation of the output, where the
-  // value d will be between 100,000 and 999,999, representing the digits
-  // in the output ASCII array, and exp is the base-10 exponent.  It would be
-  // faster to use a table here, and to look up the base-2 exponent of value,
-  // however value is an IEEE-754 64-bit number, so the table would have 2,000
-  // entries, which is not cache-friendly.
-  if (d >= 999999.5) {
-    if (d >= 1e+261) exp += 256, d *= 1e-256;
-    if (d >= 1e+133) exp += 128, d *= 1e-128;
-    if (d >= 1e+69) exp += 64, d *= 1e-64;
-    if (d >= 1e+37) exp += 32, d *= 1e-32;
-    if (d >= 1e+21) exp += 16, d *= 1e-16;
-    if (d >= 1e+13) exp += 8, d *= 1e-8;
-    if (d >= 1e+9) exp += 4, d *= 1e-4;
-    if (d >= 1e+7) exp += 2, d *= 1e-2;
-    if (d >= 1e+6) exp += 1, d *= 1e-1;
-  } else {
-    if (d < 1e-250) exp -= 256, d *= 1e256;
-    if (d < 1e-122) exp -= 128, d *= 1e128;
-    if (d < 1e-58) exp -= 64, d *= 1e64;
-    if (d < 1e-26) exp -= 32, d *= 1e32;
-    if (d < 1e-10) exp -= 16, d *= 1e16;
-    if (d < 1e-2) exp -= 8, d *= 1e8;
-    if (d < 1e+2) exp -= 4, d *= 1e4;
-    if (d < 1e+4) exp -= 2, d *= 1e2;
-    if (d < 1e+5) exp -= 1, d *= 1e1;
-  }
-  // At this point, d is in the range [99999.5..999999.5) and exp is in the
-  // range [-324..308]. Since we need to round d up, we want to add a half
-  // and truncate.
-  // However, the technique above may have lost some precision, due to its
-  // repeated multiplication by constants that each may be off by half a bit
-  // of precision.  This only matters if we're close to the edge though.
-  // Since we'd like to know if the fractional part of d is close to a half,
-  // we multiply it by 65536 and see if the fractional part is close to 32768.
-  // (The number doesn't have to be a power of two,but powers of two are faster)
-  uint64_t d64k = d * 65536;
-  int dddddd;  // A 6-digit decimal integer.
-  if ((d64k % 65536) == 32767 || (d64k % 65536) == 32768) {
-    // OK, it's fairly likely that precision was lost above, which is
-    // not a surprise given only 52 mantissa bits are available.  Therefore
-    // redo the calculation using 128-bit numbers.  (64 bits are not enough).
-
-    // Start out with digits rounded down; maybe add one below.
-    dddddd = static_cast<int>(d64k / 65536);
-
-    // mantissa is a 64-bit integer representing M.mmm... * 2^63.  The actual
-    // value we're representing, of course, is M.mmm... * 2^exp2.
-    int exp2;
-    double m = std::frexp(value, &exp2);
-    uint64_t mantissa = m * (32768.0 * 65536.0 * 65536.0 * 65536.0);
-    // std::frexp returns an m value in the range [0.5, 1.0), however we
-    // can't multiply it by 2^64 and convert to an integer because some FPUs
-    // throw an exception when converting an number higher than 2^63 into an
-    // integer - even an unsigned 64-bit integer!  Fortunately it doesn't matter
-    // since m only has 52 significant bits anyway.
-    mantissa <<= 1;
-    exp2 -= 64;  // not needed, but nice for debugging
-
-    // OK, we are here to compare:
-    //     (dddddd + 0.5) * 10^(exp-5)  vs.  mantissa * 2^exp2
-    // so we can round up dddddd if appropriate.  Those values span the full
-    // range of 600 orders of magnitude of IEE 64-bit floating-point.
-    // Fortunately, we already know they are very close, so we don't need to
-    // track the base-2 exponent of both sides.  This greatly simplifies the
-    // the math since the 2^exp2 calculation is unnecessary and the power-of-10
-    // calculation can become a power-of-5 instead.
-
-    std::pair<uint64_t, uint64_t> edge, val;
-    if (exp >= 6) {
-      // Compare (dddddd + 0.5) * 5 ^ (exp - 5) to mantissa
-      // Since we're tossing powers of two, 2 * dddddd + 1 is the
-      // same as dddddd + 0.5
-      edge = PowFive(2 * dddddd + 1, exp - 5);
-
-      val.first = mantissa;
-      val.second = 0;
-    } else {
-      // We can't compare (dddddd + 0.5) * 5 ^ (exp - 5) to mantissa as we did
-      // above because (exp - 5) is negative.  So we compare (dddddd + 0.5) to
-      // mantissa * 5 ^ (5 - exp)
-      edge = PowFive(2 * dddddd + 1, 0);
-
-      val = PowFive(mantissa, 5 - exp);
-    }
-    // printf("exp=%d %016lx %016lx vs %016lx %016lx\n", exp, val.first,
-    //        val.second, edge.first, edge.second);
-    if (val > edge) {
-      dddddd++;
-    } else if (val == edge) {
-      dddddd += (dddddd & 1);
-    }
-  } else {
-    // Here, we are not close to the edge.
-    dddddd = static_cast<int>((d64k + 32768) / 65536);
-  }
-  if (dddddd == 1000000) {
-    dddddd = 100000;
-    exp += 1;
-  }
-  exp_dig.exponent = exp;
-
-  int two_digits = dddddd / 10000;
-  dddddd -= two_digits * 10000;
-  numbers_internal::PutTwoDigits(two_digits, &exp_dig.digits[0]);
-
-  two_digits = dddddd / 100;
-  dddddd -= two_digits * 100;
-  numbers_internal::PutTwoDigits(two_digits, &exp_dig.digits[2]);
-
-  numbers_internal::PutTwoDigits(dddddd, &exp_dig.digits[4]);
-  return exp_dig;
-}
-
-// Helper function for fast formatting of floating-point.
-// The result is the same as "%g", a.k.a. "%.6g".
-size_t numbers_internal::SixDigitsToBuffer(double d, char* const buffer) {
-  static_assert(std::numeric_limits<float>::is_iec559,
-                "IEEE-754/IEC-559 support only");
-
-  char* out = buffer;  // we write data to out, incrementing as we go, but
-                       // FloatToBuffer always returns the address of the buffer
-                       // passed in.
-
-  if (std::isnan(d)) {
-    strcpy(out, "nan");  // NOLINT(runtime/printf)
-    return 3;
-  }
-  if (d == 0) {  // +0 and -0 are handled here
-    if (std::signbit(d)) *out++ = '-';
-    *out++ = '0';
-    *out = 0;
-    return out - buffer;
-  }
-  if (d < 0) {
-    *out++ = '-';
-    d = -d;
-  }
-  if (std::isinf(d)) {
-    strcpy(out, "inf");  // NOLINT(runtime/printf)
-    return out + 3 - buffer;
-  }
-
-  auto exp_dig = SplitToSix(d);
-  int exp = exp_dig.exponent;
-  const char* digits = exp_dig.digits;
-  out[0] = '0';
-  out[1] = '.';
-  switch (exp) {
-    case 5:
-      memcpy(out, &digits[0], 6), out += 6;
-      *out = 0;
-      return out - buffer;
-    case 4:
-      memcpy(out, &digits[0], 5), out += 5;
-      if (digits[5] != '0') {
-        *out++ = '.';
-        *out++ = digits[5];
-      }
-      *out = 0;
-      return out - buffer;
-    case 3:
-      memcpy(out, &digits[0], 4), out += 4;
-      if ((digits[5] | digits[4]) != '0') {
-        *out++ = '.';
-        *out++ = digits[4];
-        if (digits[5] != '0') *out++ = digits[5];
-      }
-      *out = 0;
-      return out - buffer;
-    case 2:
-      memcpy(out, &digits[0], 3), out += 3;
-      *out++ = '.';
-      memcpy(out, &digits[3], 3);
-      out += 3;
-      while (out[-1] == '0') --out;
-      if (out[-1] == '.') --out;
-      *out = 0;
-      return out - buffer;
-    case 1:
-      memcpy(out, &digits[0], 2), out += 2;
-      *out++ = '.';
-      memcpy(out, &digits[2], 4);
-      out += 4;
-      while (out[-1] == '0') --out;
-      if (out[-1] == '.') --out;
-      *out = 0;
-      return out - buffer;
-    case 0:
-      memcpy(out, &digits[0], 1), out += 1;
-      *out++ = '.';
-      memcpy(out, &digits[1], 5);
-      out += 5;
-      while (out[-1] == '0') --out;
-      if (out[-1] == '.') --out;
-      *out = 0;
-      return out - buffer;
-    case -4:
-      out[2] = '0';
-      ++out;
-      ABSL_FALLTHROUGH_INTENDED;
-    case -3:
-      out[2] = '0';
-      ++out;
-      ABSL_FALLTHROUGH_INTENDED;
-    case -2:
-      out[2] = '0';
-      ++out;
-      ABSL_FALLTHROUGH_INTENDED;
-    case -1:
-      out += 2;
-      memcpy(out, &digits[0], 6);
-      out += 6;
-      while (out[-1] == '0') --out;
-      *out = 0;
-      return out - buffer;
-  }
-  assert(exp < -4 || exp >= 6);
-  out[0] = digits[0];
-  assert(out[1] == '.');
-  out += 2;
-  memcpy(out, &digits[1], 5), out += 5;
-  while (out[-1] == '0') --out;
-  if (out[-1] == '.') --out;
-  *out++ = 'e';
-  if (exp > 0) {
-    *out++ = '+';
-  } else {
-    *out++ = '-';
-    exp = -exp;
-  }
-  if (exp > 99) {
-    int dig1 = exp / 100;
-    exp -= dig1 * 100;
-    *out++ = '0' + dig1;
-  }
-  PutTwoDigits(exp, out);
-  out += 2;
-  *out = 0;
-  return out - buffer;
-}
-
-namespace {
-// Represents integer values of digits.
-// Uses 36 to indicate an invalid character since we support
-// bases up to 36.
-static const int8_t kAsciiToInt[256] = {
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,  // 16 36s.
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 0,  1,  2,  3,  4,  5,
-    6,  7,  8,  9,  36, 36, 36, 36, 36, 36, 36, 10, 11, 12, 13, 14, 15, 16, 17,
-    18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36,
-    36, 36, 36, 36, 36, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
-    24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-    36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36, 36};
-
-// Parse the sign and optional hex or oct prefix in text.
-inline bool safe_parse_sign_and_base(absl::string_view* text /*inout*/,
-                                     int* base_ptr /*inout*/,
-                                     bool* negative_ptr /*output*/) {
-  if (text->data() == nullptr) {
-    return false;
-  }
-
-  const char* start = text->data();
-  const char* end = start + text->size();
-  int base = *base_ptr;
-
-  // Consume whitespace.
-  while (start < end && absl::ascii_isspace(start[0])) {
-    ++start;
-  }
-  while (start < end && absl::ascii_isspace(end[-1])) {
-    --end;
-  }
-  if (start >= end) {
-    return false;
-  }
-
-  // Consume sign.
-  *negative_ptr = (start[0] == '-');
-  if (*negative_ptr || start[0] == '+') {
-    ++start;
-    if (start >= end) {
-      return false;
-    }
-  }
-
-  // Consume base-dependent prefix.
-  //  base 0: "0x" -> base 16, "0" -> base 8, default -> base 10
-  //  base 16: "0x" -> base 16
-  // Also validate the base.
-  if (base == 0) {
-    if (end - start >= 2 && start[0] == '0' &&
-        (start[1] == 'x' || start[1] == 'X')) {
-      base = 16;
-      start += 2;
-      if (start >= end) {
-        // "0x" with no digits after is invalid.
-        return false;
-      }
-    } else if (end - start >= 1 && start[0] == '0') {
-      base = 8;
-      start += 1;
-    } else {
-      base = 10;
-    }
-  } else if (base == 16) {
-    if (end - start >= 2 && start[0] == '0' &&
-        (start[1] == 'x' || start[1] == 'X')) {
-      start += 2;
-      if (start >= end) {
-        // "0x" with no digits after is invalid.
-        return false;
-      }
-    }
-  } else if (base >= 2 && base <= 36) {
-    // okay
-  } else {
-    return false;
-  }
-  *text = absl::string_view(start, end - start);
-  *base_ptr = base;
-  return true;
-}
-
-// Consume digits.
-//
-// The classic loop:
-//
-//   for each digit
-//     value = value * base + digit
-//   value *= sign
-//
-// The classic loop needs overflow checking.  It also fails on the most
-// negative integer, -2147483648 in 32-bit two's complement representation.
-//
-// My improved loop:
-//
-//  if (!negative)
-//    for each digit
-//      value = value * base
-//      value = value + digit
-//  else
-//    for each digit
-//      value = value * base
-//      value = value - digit
-//
-// Overflow checking becomes simple.
-
-// Lookup tables per IntType:
-// vmax/base and vmin/base are precomputed because division costs at least 8ns.
-// TODO(junyer): Doing this per base instead (i.e. an array of structs, not a
-// struct of arrays) would probably be better in terms of d-cache for the most
-// commonly used bases.
-template <typename IntType>
-struct LookupTables {
-  ABSL_CONST_INIT static const IntType kVmaxOverBase[];
-  ABSL_CONST_INIT static const IntType kVminOverBase[];
-};
-
-// An array initializer macro for X/base where base in [0, 36].
-// However, note that lookups for base in [0, 1] should never happen because
-// base has been validated to be in [2, 36] by safe_parse_sign_and_base().
-#define X_OVER_BASE_INITIALIZER(X)                                        \
-  {                                                                       \
-    0, 0, X / 2, X / 3, X / 4, X / 5, X / 6, X / 7, X / 8, X / 9, X / 10, \
-        X / 11, X / 12, X / 13, X / 14, X / 15, X / 16, X / 17, X / 18,   \
-        X / 19, X / 20, X / 21, X / 22, X / 23, X / 24, X / 25, X / 26,   \
-        X / 27, X / 28, X / 29, X / 30, X / 31, X / 32, X / 33, X / 34,   \
-        X / 35, X / 36,                                                   \
-  }
-
-// This kVmaxOverBase is generated with
-//  for (int base = 2; base < 37; ++base) {
-//    absl::uint128 max = std::numeric_limits<absl::uint128>::max();
-//    auto result = max / base;
-//    std::cout << "    MakeUint128(" << absl::Uint128High64(result) << "u, "
-//              << absl::Uint128Low64(result) << "u),\n";
-//  }
-// See https://godbolt.org/z/aneYsb
-//
-// uint128& operator/=(uint128) is not constexpr, so hardcode the resulting
-// array to avoid a static initializer.
-template<>
-const uint128 LookupTables<uint128>::kVmaxOverBase[] = {
-    0,
-    0,
-    MakeUint128(9223372036854775807u, 18446744073709551615u),
-    MakeUint128(6148914691236517205u, 6148914691236517205u),
-    MakeUint128(4611686018427387903u, 18446744073709551615u),
-    MakeUint128(3689348814741910323u, 3689348814741910323u),
-    MakeUint128(3074457345618258602u, 12297829382473034410u),
-    MakeUint128(2635249153387078802u, 5270498306774157604u),
-    MakeUint128(2305843009213693951u, 18446744073709551615u),
-    MakeUint128(2049638230412172401u, 14347467612885206812u),
-    MakeUint128(1844674407370955161u, 11068046444225730969u),
-    MakeUint128(1676976733973595601u, 8384883669867978007u),
-    MakeUint128(1537228672809129301u, 6148914691236517205u),
-    MakeUint128(1418980313362273201u, 4256940940086819603u),
-    MakeUint128(1317624576693539401u, 2635249153387078802u),
-    MakeUint128(1229782938247303441u, 1229782938247303441u),
-    MakeUint128(1152921504606846975u, 18446744073709551615u),
-    MakeUint128(1085102592571150095u, 1085102592571150095u),
-    MakeUint128(1024819115206086200u, 16397105843297379214u),
-    MakeUint128(970881267037344821u, 16504981539634861972u),
-    MakeUint128(922337203685477580u, 14757395258967641292u),
-    MakeUint128(878416384462359600u, 14054662151397753612u),
-    MakeUint128(838488366986797800u, 13415813871788764811u),
-    MakeUint128(802032351030850070u, 4812194106185100421u),
-    MakeUint128(768614336404564650u, 12297829382473034410u),
-    MakeUint128(737869762948382064u, 11805916207174113034u),
-    MakeUint128(709490156681136600u, 11351842506898185609u),
-    MakeUint128(683212743470724133u, 17080318586768103348u),
-    MakeUint128(658812288346769700u, 10540996613548315209u),
-    MakeUint128(636094623231363848u, 15266270957552732371u),
-    MakeUint128(614891469123651720u, 9838263505978427528u),
-    MakeUint128(595056260442243600u, 9520900167075897608u),
-    MakeUint128(576460752303423487u, 18446744073709551615u),
-    MakeUint128(558992244657865200u, 8943875914525843207u),
-    MakeUint128(542551296285575047u, 9765923333140350855u),
-    MakeUint128(527049830677415760u, 8432797290838652167u),
-    MakeUint128(512409557603043100u, 8198552921648689607u),
-};
-
-// This kVmaxOverBase generated with
-//   for (int base = 2; base < 37; ++base) {
-//    absl::int128 max = std::numeric_limits<absl::int128>::max();
-//    auto result = max / base;
-//    std::cout << "\tMakeInt128(" << absl::Int128High64(result) << ", "
-//              << absl::Int128Low64(result) << "u),\n";
-//  }
-// See https://godbolt.org/z/7djYWz
-//
-// int128& operator/=(int128) is not constexpr, so hardcode the resulting array
-// to avoid a static initializer.
-template<>
-const int128 LookupTables<int128>::kVmaxOverBase[] = {
-    0,
-    0,
-    MakeInt128(4611686018427387903, 18446744073709551615u),
-    MakeInt128(3074457345618258602, 12297829382473034410u),
-    MakeInt128(2305843009213693951, 18446744073709551615u),
-    MakeInt128(1844674407370955161, 11068046444225730969u),
-    MakeInt128(1537228672809129301, 6148914691236517205u),
-    MakeInt128(1317624576693539401, 2635249153387078802u),
-    MakeInt128(1152921504606846975, 18446744073709551615u),
-    MakeInt128(1024819115206086200, 16397105843297379214u),
-    MakeInt128(922337203685477580, 14757395258967641292u),
-    MakeInt128(838488366986797800, 13415813871788764811u),
-    MakeInt128(768614336404564650, 12297829382473034410u),
-    MakeInt128(709490156681136600, 11351842506898185609u),
-    MakeInt128(658812288346769700, 10540996613548315209u),
-    MakeInt128(614891469123651720, 9838263505978427528u),
-    MakeInt128(576460752303423487, 18446744073709551615u),
-    MakeInt128(542551296285575047, 9765923333140350855u),
-    MakeInt128(512409557603043100, 8198552921648689607u),
-    MakeInt128(485440633518672410, 17475862806672206794u),
-    MakeInt128(461168601842738790, 7378697629483820646u),
-    MakeInt128(439208192231179800, 7027331075698876806u),
-    MakeInt128(419244183493398900, 6707906935894382405u),
-    MakeInt128(401016175515425035, 2406097053092550210u),
-    MakeInt128(384307168202282325, 6148914691236517205u),
-    MakeInt128(368934881474191032, 5902958103587056517u),
-    MakeInt128(354745078340568300, 5675921253449092804u),
-    MakeInt128(341606371735362066, 17763531330238827482u),
-    MakeInt128(329406144173384850, 5270498306774157604u),
-    MakeInt128(318047311615681924, 7633135478776366185u),
-    MakeInt128(307445734561825860, 4919131752989213764u),
-    MakeInt128(297528130221121800, 4760450083537948804u),
-    MakeInt128(288230376151711743, 18446744073709551615u),
-    MakeInt128(279496122328932600, 4471937957262921603u),
-    MakeInt128(271275648142787523, 14106333703424951235u),
-    MakeInt128(263524915338707880, 4216398645419326083u),
-    MakeInt128(256204778801521550, 4099276460824344803u),
-};
-
-// This kVminOverBase generated with
-//  for (int base = 2; base < 37; ++base) {
-//    absl::int128 min = std::numeric_limits<absl::int128>::min();
-//    auto result = min / base;
-//    std::cout << "\tMakeInt128(" << absl::Int128High64(result) << ", "
-//              << absl::Int128Low64(result) << "u),\n";
-//  }
-//
-// See https://godbolt.org/z/7djYWz
-//
-// int128& operator/=(int128) is not constexpr, so hardcode the resulting array
-// to avoid a static initializer.
-template<>
-const int128 LookupTables<int128>::kVminOverBase[] = {
-    0,
-    0,
-    MakeInt128(-4611686018427387904, 0u),
-    MakeInt128(-3074457345618258603, 6148914691236517206u),
-    MakeInt128(-2305843009213693952, 0u),
-    MakeInt128(-1844674407370955162, 7378697629483820647u),
-    MakeInt128(-1537228672809129302, 12297829382473034411u),
-    MakeInt128(-1317624576693539402, 15811494920322472814u),
-    MakeInt128(-1152921504606846976, 0u),
-    MakeInt128(-1024819115206086201, 2049638230412172402u),
-    MakeInt128(-922337203685477581, 3689348814741910324u),
-    MakeInt128(-838488366986797801, 5030930201920786805u),
-    MakeInt128(-768614336404564651, 6148914691236517206u),
-    MakeInt128(-709490156681136601, 7094901566811366007u),
-    MakeInt128(-658812288346769701, 7905747460161236407u),
-    MakeInt128(-614891469123651721, 8608480567731124088u),
-    MakeInt128(-576460752303423488, 0u),
-    MakeInt128(-542551296285575048, 8680820740569200761u),
-    MakeInt128(-512409557603043101, 10248191152060862009u),
-    MakeInt128(-485440633518672411, 970881267037344822u),
-    MakeInt128(-461168601842738791, 11068046444225730970u),
-    MakeInt128(-439208192231179801, 11419412998010674810u),
-    MakeInt128(-419244183493398901, 11738837137815169211u),
-    MakeInt128(-401016175515425036, 16040647020617001406u),
-    MakeInt128(-384307168202282326, 12297829382473034411u),
-    MakeInt128(-368934881474191033, 12543785970122495099u),
-    MakeInt128(-354745078340568301, 12770822820260458812u),
-    MakeInt128(-341606371735362067, 683212743470724134u),
-    MakeInt128(-329406144173384851, 13176245766935394012u),
-    MakeInt128(-318047311615681925, 10813608594933185431u),
-    MakeInt128(-307445734561825861, 13527612320720337852u),
-    MakeInt128(-297528130221121801, 13686293990171602812u),
-    MakeInt128(-288230376151711744, 0u),
-    MakeInt128(-279496122328932601, 13974806116446630013u),
-    MakeInt128(-271275648142787524, 4340410370284600381u),
-    MakeInt128(-263524915338707881, 14230345428290225533u),
-    MakeInt128(-256204778801521551, 14347467612885206813u),
-};
-
-template <typename IntType>
-const IntType LookupTables<IntType>::kVmaxOverBase[] =
-    X_OVER_BASE_INITIALIZER(std::numeric_limits<IntType>::max());
-
-template <typename IntType>
-const IntType LookupTables<IntType>::kVminOverBase[] =
-    X_OVER_BASE_INITIALIZER(std::numeric_limits<IntType>::min());
-
-#undef X_OVER_BASE_INITIALIZER
-
-template <typename IntType>
-inline bool safe_parse_positive_int(absl::string_view text, int base,
-                                    IntType* value_p) {
-  IntType value = 0;
-  const IntType vmax = std::numeric_limits<IntType>::max();
-  assert(vmax > 0);
-  assert(base >= 0);
-  assert(vmax >= static_cast<IntType>(base));
-  const IntType vmax_over_base = LookupTables<IntType>::kVmaxOverBase[base];
-  assert(base < 2 ||
-         std::numeric_limits<IntType>::max() / base == vmax_over_base);
-  const char* start = text.data();
-  const char* end = start + text.size();
-  // loop over digits
-  for (; start < end; ++start) {
-    unsigned char c = static_cast<unsigned char>(start[0]);
-    int digit = kAsciiToInt[c];
-    if (digit >= base) {
-      *value_p = value;
-      return false;
-    }
-    if (value > vmax_over_base) {
-      *value_p = vmax;
-      return false;
-    }
-    value *= base;
-    if (value > vmax - digit) {
-      *value_p = vmax;
-      return false;
-    }
-    value += digit;
-  }
-  *value_p = value;
-  return true;
-}
-
-template <typename IntType>
-inline bool safe_parse_negative_int(absl::string_view text, int base,
-                                    IntType* value_p) {
-  IntType value = 0;
-  const IntType vmin = std::numeric_limits<IntType>::min();
-  assert(vmin < 0);
-  assert(vmin <= 0 - base);
-  IntType vmin_over_base = LookupTables<IntType>::kVminOverBase[base];
-  assert(base < 2 ||
-         std::numeric_limits<IntType>::min() / base == vmin_over_base);
-  // 2003 c++ standard [expr.mul]
-  // "... the sign of the remainder is implementation-defined."
-  // Although (vmin/base)*base + vmin%base is always vmin.
-  // 2011 c++ standard tightens the spec but we cannot rely on it.
-  // TODO(junyer): Handle this in the lookup table generation.
-  if (vmin % base > 0) {
-    vmin_over_base += 1;
-  }
-  const char* start = text.data();
-  const char* end = start + text.size();
-  // loop over digits
-  for (; start < end; ++start) {
-    unsigned char c = static_cast<unsigned char>(start[0]);
-    int digit = kAsciiToInt[c];
-    if (digit >= base) {
-      *value_p = value;
-      return false;
-    }
-    if (value < vmin_over_base) {
-      *value_p = vmin;
-      return false;
-    }
-    value *= base;
-    if (value < vmin + digit) {
-      *value_p = vmin;
-      return false;
-    }
-    value -= digit;
-  }
-  *value_p = value;
-  return true;
-}
-
-// Input format based on POSIX.1-2008 strtol
-// http://pubs.opengroup.org/onlinepubs/9699919799/functions/strtol.html
-template <typename IntType>
-inline bool safe_int_internal(absl::string_view text, IntType* value_p,
-                              int base) {
-  *value_p = 0;
-  bool negative;
-  if (!safe_parse_sign_and_base(&text, &base, &negative)) {
-    return false;
-  }
-  if (!negative) {
-    return safe_parse_positive_int(text, base, value_p);
-  } else {
-    return safe_parse_negative_int(text, base, value_p);
-  }
-}
-
-template <typename IntType>
-inline bool safe_uint_internal(absl::string_view text, IntType* value_p,
-                               int base) {
-  *value_p = 0;
-  bool negative;
-  if (!safe_parse_sign_and_base(&text, &base, &negative) || negative) {
-    return false;
-  }
-  return safe_parse_positive_int(text, base, value_p);
-}
-}  // anonymous namespace
-
-namespace numbers_internal {
-
-// Digit conversion.
-ABSL_CONST_INIT ABSL_DLL const char kHexChar[] =
-    "0123456789abcdef";
-
-ABSL_CONST_INIT ABSL_DLL const char kHexTable[513] =
-    "000102030405060708090a0b0c0d0e0f"
-    "101112131415161718191a1b1c1d1e1f"
-    "202122232425262728292a2b2c2d2e2f"
-    "303132333435363738393a3b3c3d3e3f"
-    "404142434445464748494a4b4c4d4e4f"
-    "505152535455565758595a5b5c5d5e5f"
-    "606162636465666768696a6b6c6d6e6f"
-    "707172737475767778797a7b7c7d7e7f"
-    "808182838485868788898a8b8c8d8e8f"
-    "909192939495969798999a9b9c9d9e9f"
-    "a0a1a2a3a4a5a6a7a8a9aaabacadaeaf"
-    "b0b1b2b3b4b5b6b7b8b9babbbcbdbebf"
-    "c0c1c2c3c4c5c6c7c8c9cacbcccdcecf"
-    "d0d1d2d3d4d5d6d7d8d9dadbdcdddedf"
-    "e0e1e2e3e4e5e6e7e8e9eaebecedeeef"
-    "f0f1f2f3f4f5f6f7f8f9fafbfcfdfeff";
-
-ABSL_CONST_INIT ABSL_DLL const char two_ASCII_digits[100][2] = {
-    {'0', '0'}, {'0', '1'}, {'0', '2'}, {'0', '3'}, {'0', '4'}, {'0', '5'},
-    {'0', '6'}, {'0', '7'}, {'0', '8'}, {'0', '9'}, {'1', '0'}, {'1', '1'},
-    {'1', '2'}, {'1', '3'}, {'1', '4'}, {'1', '5'}, {'1', '6'}, {'1', '7'},
-    {'1', '8'}, {'1', '9'}, {'2', '0'}, {'2', '1'}, {'2', '2'}, {'2', '3'},
-    {'2', '4'}, {'2', '5'}, {'2', '6'}, {'2', '7'}, {'2', '8'}, {'2', '9'},
-    {'3', '0'}, {'3', '1'}, {'3', '2'}, {'3', '3'}, {'3', '4'}, {'3', '5'},
-    {'3', '6'}, {'3', '7'}, {'3', '8'}, {'3', '9'}, {'4', '0'}, {'4', '1'},
-    {'4', '2'}, {'4', '3'}, {'4', '4'}, {'4', '5'}, {'4', '6'}, {'4', '7'},
-    {'4', '8'}, {'4', '9'}, {'5', '0'}, {'5', '1'}, {'5', '2'}, {'5', '3'},
-    {'5', '4'}, {'5', '5'}, {'5', '6'}, {'5', '7'}, {'5', '8'}, {'5', '9'},
-    {'6', '0'}, {'6', '1'}, {'6', '2'}, {'6', '3'}, {'6', '4'}, {'6', '5'},
-    {'6', '6'}, {'6', '7'}, {'6', '8'}, {'6', '9'}, {'7', '0'}, {'7', '1'},
-    {'7', '2'}, {'7', '3'}, {'7', '4'}, {'7', '5'}, {'7', '6'}, {'7', '7'},
-    {'7', '8'}, {'7', '9'}, {'8', '0'}, {'8', '1'}, {'8', '2'}, {'8', '3'},
-    {'8', '4'}, {'8', '5'}, {'8', '6'}, {'8', '7'}, {'8', '8'}, {'8', '9'},
-    {'9', '0'}, {'9', '1'}, {'9', '2'}, {'9', '3'}, {'9', '4'}, {'9', '5'},
-    {'9', '6'}, {'9', '7'}, {'9', '8'}, {'9', '9'}};
-
-bool safe_strto32_base(absl::string_view text, int32_t* value, int base) {
-  return safe_int_internal<int32_t>(text, value, base);
-}
-
-bool safe_strto64_base(absl::string_view text, int64_t* value, int base) {
-  return safe_int_internal<int64_t>(text, value, base);
-}
-
-bool safe_strto128_base(absl::string_view text, int128* value, int base) {
-  return safe_int_internal<absl::int128>(text, value, base);
-}
-
-bool safe_strtou32_base(absl::string_view text, uint32_t* value, int base) {
-  return safe_uint_internal<uint32_t>(text, value, base);
-}
-
-bool safe_strtou64_base(absl::string_view text, uint64_t* value, int base) {
-  return safe_uint_internal<uint64_t>(text, value, base);
-}
-
-bool safe_strtou128_base(absl::string_view text, uint128* value, int base) {
-  return safe_uint_internal<absl::uint128>(text, value, base);
-}
-
-}  // namespace numbers_internal
-ABSL_NAMESPACE_END
-}  // namespace absl