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double-conversion-strtod.cpp (24127B)

---

// © 2018 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
//
// From the double-conversion library. Original license:
//
// Copyright 2010 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
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//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// ICU PATCH: ifdef around UCONFIG_NO_FORMATTING
#include "unicode/utypes.h"
#if !UCONFIG_NO_FORMATTING

#include <climits>
#include <cstdarg>

// ICU PATCH: Customize header file paths for ICU.

#include "double-conversion-bignum.h"
#include "double-conversion-cached-powers.h"
#include "double-conversion-ieee.h"
#include "double-conversion-strtod.h"

// ICU PATCH: Wrap in ICU namespace
U_NAMESPACE_BEGIN

namespace double_conversion {

#if defined(DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS)
// 2^53 = 9007199254740992.
// Any integer with at most 15 decimal digits will hence fit into a double
// (which has a 53bit significand) without loss of precision.
static const int kMaxExactDoubleIntegerDecimalDigits = 15;
#endif // #if defined(DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS)
// 2^64 = 18446744073709551616 > 10^19
static const int kMaxUint64DecimalDigits = 19;

// Max double: 1.7976931348623157 x 10^308
// Min non-zero double: 4.9406564584124654 x 10^-324
// Any x >= 10^309 is interpreted as +infinity.
// Any x <= 10^-324 is interpreted as 0.
// Note that 2.5e-324 (despite being smaller than the min double) will be read
// as non-zero (equal to the min non-zero double).
static const int kMaxDecimalPower = 309;
static const int kMinDecimalPower = -324;

// 2^64 = 18446744073709551616
static const uint64_t kMaxUint64 = DOUBLE_CONVERSION_UINT64_2PART_C(0xFFFFFFFF, FFFFFFFF);


#if defined(DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS)
static const double exact_powers_of_ten[] = {
 1.0,  // 10^0
 10.0,
 100.0,
 1000.0,
 10000.0,
 100000.0,
 1000000.0,
 10000000.0,
 100000000.0,
 1000000000.0,
 10000000000.0,  // 10^10
 100000000000.0,
 1000000000000.0,
 10000000000000.0,
 100000000000000.0,
 1000000000000000.0,
 10000000000000000.0,
 100000000000000000.0,
 1000000000000000000.0,
 10000000000000000000.0,
 100000000000000000000.0,  // 10^20
 1000000000000000000000.0,
 // 10^22 = 0x21e19e0c9bab2400000 = 0x878678326eac9 * 2^22
 10000000000000000000000.0
};
static const int kExactPowersOfTenSize = DOUBLE_CONVERSION_ARRAY_SIZE(exact_powers_of_ten);
#endif // #if defined(DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS)

// Maximum number of significant digits in the decimal representation.
// In fact the value is 772 (see conversions.cc), but to give us some margin
// we round up to 780.
static const int kMaxSignificantDecimalDigits = 780;

static Vector<const char> TrimLeadingZeros(Vector<const char> buffer) {
 for (int i = 0; i < buffer.length(); i++) {
   if (buffer[i] != '0') {
     return buffer.SubVector(i, buffer.length());
   }
 }
 return Vector<const char>(buffer.start(), 0);
}

static void CutToMaxSignificantDigits(Vector<const char> buffer,
                                      int exponent,
                                      char* significant_buffer,
                                      int* significant_exponent) {
 for (int i = 0; i < kMaxSignificantDecimalDigits - 1; ++i) {
   significant_buffer[i] = buffer[i];
 }
 // The input buffer has been trimmed. Therefore the last digit must be
 // different from '0'.
 DOUBLE_CONVERSION_ASSERT(buffer[buffer.length() - 1] != '0');
 // Set the last digit to be non-zero. This is sufficient to guarantee
 // correct rounding.
 significant_buffer[kMaxSignificantDecimalDigits - 1] = '1';
 *significant_exponent =
     exponent + (buffer.length() - kMaxSignificantDecimalDigits);
}


// Trims the buffer and cuts it to at most kMaxSignificantDecimalDigits.
// If possible the input-buffer is reused, but if the buffer needs to be
// modified (due to cutting), then the input needs to be copied into the
// buffer_copy_space.
static void TrimAndCut(Vector<const char> buffer, int exponent,
                      char* buffer_copy_space, int space_size,
                      Vector<const char>* trimmed, int* updated_exponent) {
 Vector<const char> left_trimmed = TrimLeadingZeros(buffer);
 Vector<const char> right_trimmed = TrimTrailingZeros(left_trimmed);
 exponent += left_trimmed.length() - right_trimmed.length();
 if (right_trimmed.length() > kMaxSignificantDecimalDigits) {
   (void) space_size;  // Mark variable as used.
   DOUBLE_CONVERSION_ASSERT(space_size >= kMaxSignificantDecimalDigits);
   CutToMaxSignificantDigits(right_trimmed, exponent,
                             buffer_copy_space, updated_exponent);
   *trimmed = Vector<const char>(buffer_copy_space,
                                kMaxSignificantDecimalDigits);
 } else {
   *trimmed = right_trimmed;
   *updated_exponent = exponent;
 }
}


// Reads digits from the buffer and converts them to a uint64.
// Reads in as many digits as fit into a uint64.
// When the string starts with "1844674407370955161" no further digit is read.
// Since 2^64 = 18446744073709551616 it would still be possible read another
// digit if it was less or equal than 6, but this would complicate the code.
static uint64_t ReadUint64(Vector<const char> buffer,
                          int* number_of_read_digits) {
 uint64_t result = 0;
 int i = 0;
 while (i < buffer.length() && result <= (kMaxUint64 / 10 - 1)) {
   int digit = buffer[i++] - '0';
   DOUBLE_CONVERSION_ASSERT(0 <= digit && digit <= 9);
   result = 10 * result + digit;
 }
 *number_of_read_digits = i;
 return result;
}


// Reads a DiyFp from the buffer.
// The returned DiyFp is not necessarily normalized.
// If remaining_decimals is zero then the returned DiyFp is accurate.
// Otherwise it has been rounded and has error of at most 1/2 ulp.
static void ReadDiyFp(Vector<const char> buffer,
                     DiyFp* result,
                     int* remaining_decimals) {
 int read_digits;
 uint64_t significand = ReadUint64(buffer, &read_digits);
 if (buffer.length() == read_digits) {
   *result = DiyFp(significand, 0);
   *remaining_decimals = 0;
 } else {
   // Round the significand.
   if (buffer[read_digits] >= '5') {
     significand++;
   }
   // Compute the binary exponent.
   int exponent = 0;
   *result = DiyFp(significand, exponent);
   *remaining_decimals = buffer.length() - read_digits;
 }
}


static bool DoubleStrtod(Vector<const char> trimmed,
                        int exponent,
                        double* result) {
#if !defined(DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS)
 // Avoid "unused parameter" warnings
 (void) trimmed;
 (void) exponent;
 (void) result;
 // On x86 the floating-point stack can be 64 or 80 bits wide. If it is
 // 80 bits wide (as is the case on Linux) then double-rounding occurs and the
 // result is not accurate.
 // We know that Windows32 uses 64 bits and is therefore accurate.
 return false;
#else
 if (trimmed.length() <= kMaxExactDoubleIntegerDecimalDigits) {
   int read_digits;
   // The trimmed input fits into a double.
   // If the 10^exponent (resp. 10^-exponent) fits into a double too then we
   // can compute the result-double simply by multiplying (resp. dividing) the
   // two numbers.
   // This is possible because IEEE guarantees that floating-point operations
   // return the best possible approximation.
   if (exponent < 0 && -exponent < kExactPowersOfTenSize) {
     // 10^-exponent fits into a double.
     *result = static_cast<double>(ReadUint64(trimmed, &read_digits));
     DOUBLE_CONVERSION_ASSERT(read_digits == trimmed.length());
     *result /= exact_powers_of_ten[-exponent];
     return true;
   }
   if (0 <= exponent && exponent < kExactPowersOfTenSize) {
     // 10^exponent fits into a double.
     *result = static_cast<double>(ReadUint64(trimmed, &read_digits));
     DOUBLE_CONVERSION_ASSERT(read_digits == trimmed.length());
     *result *= exact_powers_of_ten[exponent];
     return true;
   }
   int remaining_digits =
       kMaxExactDoubleIntegerDecimalDigits - trimmed.length();
   if ((0 <= exponent) &&
       (exponent - remaining_digits < kExactPowersOfTenSize)) {
     // The trimmed string was short and we can multiply it with
     // 10^remaining_digits. As a result the remaining exponent now fits
     // into a double too.
     *result = static_cast<double>(ReadUint64(trimmed, &read_digits));
     DOUBLE_CONVERSION_ASSERT(read_digits == trimmed.length());
     *result *= exact_powers_of_ten[remaining_digits];
     *result *= exact_powers_of_ten[exponent - remaining_digits];
     return true;
   }
 }
 return false;
#endif
}


// Returns 10^exponent as an exact DiyFp.
// The given exponent must be in the range [1; kDecimalExponentDistance[.
static DiyFp AdjustmentPowerOfTen(int exponent) {
 DOUBLE_CONVERSION_ASSERT(0 < exponent);
 DOUBLE_CONVERSION_ASSERT(exponent < PowersOfTenCache::kDecimalExponentDistance);
 // Simply hardcode the remaining powers for the given decimal exponent
 // distance.
 DOUBLE_CONVERSION_ASSERT(PowersOfTenCache::kDecimalExponentDistance == 8);
 switch (exponent) {
   case 1: return DiyFp(DOUBLE_CONVERSION_UINT64_2PART_C(0xa0000000, 00000000), -60);
   case 2: return DiyFp(DOUBLE_CONVERSION_UINT64_2PART_C(0xc8000000, 00000000), -57);
   case 3: return DiyFp(DOUBLE_CONVERSION_UINT64_2PART_C(0xfa000000, 00000000), -54);
   case 4: return DiyFp(DOUBLE_CONVERSION_UINT64_2PART_C(0x9c400000, 00000000), -50);
   case 5: return DiyFp(DOUBLE_CONVERSION_UINT64_2PART_C(0xc3500000, 00000000), -47);
   case 6: return DiyFp(DOUBLE_CONVERSION_UINT64_2PART_C(0xf4240000, 00000000), -44);
   case 7: return DiyFp(DOUBLE_CONVERSION_UINT64_2PART_C(0x98968000, 00000000), -40);
   default:
     DOUBLE_CONVERSION_UNREACHABLE();
 }
}


// If the function returns true then the result is the correct double.
// Otherwise it is either the correct double or the double that is just below
// the correct double.
static bool DiyFpStrtod(Vector<const char> buffer,
                       int exponent,
                       double* result) {
 DiyFp input;
 int remaining_decimals;
 ReadDiyFp(buffer, &input, &remaining_decimals);
 // Since we may have dropped some digits the input is not accurate.
 // If remaining_decimals is different than 0 than the error is at most
 // .5 ulp (unit in the last place).
 // We don't want to deal with fractions and therefore keep a common
 // denominator.
 const int kDenominatorLog = 3;
 const int kDenominator = 1 << kDenominatorLog;
 // Move the remaining decimals into the exponent.
 exponent += remaining_decimals;
 uint64_t error = (remaining_decimals == 0 ? 0 : kDenominator / 2);

 int old_e = input.e();
 input.Normalize();
 error <<= old_e - input.e();

 DOUBLE_CONVERSION_ASSERT(exponent <= PowersOfTenCache::kMaxDecimalExponent);
 if (exponent < PowersOfTenCache::kMinDecimalExponent) {
   *result = 0.0;
   return true;
 }
 DiyFp cached_power;
 int cached_decimal_exponent;
 PowersOfTenCache::GetCachedPowerForDecimalExponent(exponent,
                                                    &cached_power,
                                                    &cached_decimal_exponent);

 if (cached_decimal_exponent != exponent) {
   int adjustment_exponent = exponent - cached_decimal_exponent;
   DiyFp adjustment_power = AdjustmentPowerOfTen(adjustment_exponent);
   input.Multiply(adjustment_power);
   if (kMaxUint64DecimalDigits - buffer.length() >= adjustment_exponent) {
     // The product of input with the adjustment power fits into a 64 bit
     // integer.
     DOUBLE_CONVERSION_ASSERT(DiyFp::kSignificandSize == 64);
   } else {
     // The adjustment power is exact. There is hence only an error of 0.5.
     error += kDenominator / 2;
   }
 }

 input.Multiply(cached_power);
 // The error introduced by a multiplication of a*b equals
 //   error_a + error_b + error_a*error_b/2^64 + 0.5
 // Substituting a with 'input' and b with 'cached_power' we have
 //   error_b = 0.5  (all cached powers have an error of less than 0.5 ulp),
 //   error_ab = 0 or 1 / kDenominator > error_a*error_b/ 2^64
 int error_b = kDenominator / 2;
 int error_ab = (error == 0 ? 0 : 1);  // We round up to 1.
 int fixed_error = kDenominator / 2;
 error += error_b + error_ab + fixed_error;

 old_e = input.e();
 input.Normalize();
 error <<= old_e - input.e();

 // See if the double's significand changes if we add/subtract the error.
 int order_of_magnitude = DiyFp::kSignificandSize + input.e();
 int effective_significand_size =
     Double::SignificandSizeForOrderOfMagnitude(order_of_magnitude);
 int precision_digits_count =
     DiyFp::kSignificandSize - effective_significand_size;
 if (precision_digits_count + kDenominatorLog >= DiyFp::kSignificandSize) {
   // This can only happen for very small denormals. In this case the
   // half-way multiplied by the denominator exceeds the range of an uint64.
   // Simply shift everything to the right.
   int shift_amount = (precision_digits_count + kDenominatorLog) -
       DiyFp::kSignificandSize + 1;
   input.set_f(input.f() >> shift_amount);
   input.set_e(input.e() + shift_amount);
   // We add 1 for the lost precision of error, and kDenominator for
   // the lost precision of input.f().
   error = (error >> shift_amount) + 1 + kDenominator;
   precision_digits_count -= shift_amount;
 }
 // We use uint64_ts now. This only works if the DiyFp uses uint64_ts too.
 DOUBLE_CONVERSION_ASSERT(DiyFp::kSignificandSize == 64);
 DOUBLE_CONVERSION_ASSERT(precision_digits_count < 64);
 uint64_t one64 = 1;
 uint64_t precision_bits_mask = (one64 << precision_digits_count) - 1;
 uint64_t precision_bits = input.f() & precision_bits_mask;
 uint64_t half_way = one64 << (precision_digits_count - 1);
 precision_bits *= kDenominator;
 half_way *= kDenominator;
 DiyFp rounded_input(input.f() >> precision_digits_count,
                     input.e() + precision_digits_count);
 if (precision_bits >= half_way + error) {
   rounded_input.set_f(rounded_input.f() + 1);
 }
 // If the last_bits are too close to the half-way case than we are too
 // inaccurate and round down. In this case we return false so that we can
 // fall back to a more precise algorithm.

 *result = Double(rounded_input).value();
 if (half_way - error < precision_bits && precision_bits < half_way + error) {
   // Too imprecise. The caller will have to fall back to a slower version.
   // However the returned number is guaranteed to be either the correct
   // double, or the next-lower double.
   return false;
 } else {
   return true;
 }
}


// Returns
//   - -1 if buffer*10^exponent < diy_fp.
//   -  0 if buffer*10^exponent == diy_fp.
//   - +1 if buffer*10^exponent > diy_fp.
// Preconditions:
//   buffer.length() + exponent <= kMaxDecimalPower + 1
//   buffer.length() + exponent > kMinDecimalPower
//   buffer.length() <= kMaxDecimalSignificantDigits
static int CompareBufferWithDiyFp(Vector<const char> buffer,
                                 int exponent,
                                 DiyFp diy_fp) {
 DOUBLE_CONVERSION_ASSERT(buffer.length() + exponent <= kMaxDecimalPower + 1);
 DOUBLE_CONVERSION_ASSERT(buffer.length() + exponent > kMinDecimalPower);
 DOUBLE_CONVERSION_ASSERT(buffer.length() <= kMaxSignificantDecimalDigits);
 // Make sure that the Bignum will be able to hold all our numbers.
 // Our Bignum implementation has a separate field for exponents. Shifts will
 // consume at most one bigit (< 64 bits).
 // ln(10) == 3.3219...
 DOUBLE_CONVERSION_ASSERT(((kMaxDecimalPower + 1) * 333 / 100) < Bignum::kMaxSignificantBits);
 Bignum buffer_bignum;
 Bignum diy_fp_bignum;
 buffer_bignum.AssignDecimalString(buffer);
 diy_fp_bignum.AssignUInt64(diy_fp.f());
 if (exponent >= 0) {
   buffer_bignum.MultiplyByPowerOfTen(exponent);
 } else {
   diy_fp_bignum.MultiplyByPowerOfTen(-exponent);
 }
 if (diy_fp.e() > 0) {
   diy_fp_bignum.ShiftLeft(diy_fp.e());
 } else {
   buffer_bignum.ShiftLeft(-diy_fp.e());
 }
 return Bignum::Compare(buffer_bignum, diy_fp_bignum);
}


// Returns true if the guess is the correct double.
// Returns false, when guess is either correct or the next-lower double.
static bool ComputeGuess(Vector<const char> trimmed, int exponent,
                        double* guess) {
 if (trimmed.length() == 0) {
   *guess = 0.0;
   return true;
 }
 if (exponent + trimmed.length() - 1 >= kMaxDecimalPower) {
   *guess = Double::Infinity();
   return true;
 }
 if (exponent + trimmed.length() <= kMinDecimalPower) {
   *guess = 0.0;
   return true;
 }

 if (DoubleStrtod(trimmed, exponent, guess) ||
     DiyFpStrtod(trimmed, exponent, guess)) {
   return true;
 }
 if (*guess == Double::Infinity()) {
   return true;
 }
 return false;
}

#if U_DEBUG // needed for ICU only in debug mode
static bool IsDigit(const char d) {
 return ('0' <= d) && (d <= '9');
}

static bool IsNonZeroDigit(const char d) {
 return ('1' <= d) && (d <= '9');
}

#ifdef __has_cpp_attribute
#if __has_cpp_attribute(maybe_unused)
[[maybe_unused]]
#endif
#endif
static bool AssertTrimmedDigits(const Vector<const char>& buffer) {
 for(int i = 0; i < buffer.length(); ++i) {
   if(!IsDigit(buffer[i])) {
     return false;
   }
 }
 return (buffer.length() == 0) || (IsNonZeroDigit(buffer[0]) && IsNonZeroDigit(buffer[buffer.length()-1]));
}
#endif // needed for ICU only in debug mode

double StrtodTrimmed(Vector<const char> trimmed, int exponent) {
 DOUBLE_CONVERSION_ASSERT(trimmed.length() <= kMaxSignificantDecimalDigits);
 DOUBLE_CONVERSION_ASSERT(AssertTrimmedDigits(trimmed));
 double guess;
 const bool is_correct = ComputeGuess(trimmed, exponent, &guess);
 if (is_correct) {
   return guess;
 }
 DiyFp upper_boundary = Double(guess).UpperBoundary();
 int comparison = CompareBufferWithDiyFp(trimmed, exponent, upper_boundary);
 if (comparison < 0) {
   return guess;
 } else if (comparison > 0) {
   return Double(guess).NextDouble();
 } else if ((Double(guess).Significand() & 1) == 0) {
   // Round towards even.
   return guess;
 } else {
   return Double(guess).NextDouble();
 }
}

double Strtod(Vector<const char> buffer, int exponent) {
 char copy_buffer[kMaxSignificantDecimalDigits];
 Vector<const char> trimmed;
 int updated_exponent;
 TrimAndCut(buffer, exponent, copy_buffer, kMaxSignificantDecimalDigits,
            &trimmed, &updated_exponent);
 return StrtodTrimmed(trimmed, updated_exponent);
}

static float SanitizedDoubletof(double d) {
 DOUBLE_CONVERSION_ASSERT(d >= 0.0);
 // ASAN has a sanitize check that disallows casting doubles to floats if
 // they are too big.
 // https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html#available-checks
 // The behavior should be covered by IEEE 754, but some projects use this
 // flag, so work around it.
 float max_finite = 3.4028234663852885981170418348451692544e+38;
 // The half-way point between the max-finite and infinity value.
 // Since infinity has an even significand everything equal or greater than
 // this value should become infinity.
 double half_max_finite_infinity =
     3.40282356779733661637539395458142568448e+38;
 if (d >= max_finite) {
   if (d >= half_max_finite_infinity) {
     return Single::Infinity();
   } else {
     return max_finite;
   }
 } else {
   return static_cast<float>(d);
 }
}

float Strtof(Vector<const char> buffer, int exponent) {
 char copy_buffer[kMaxSignificantDecimalDigits];
 Vector<const char> trimmed;
 int updated_exponent;
 TrimAndCut(buffer, exponent, copy_buffer, kMaxSignificantDecimalDigits,
            &trimmed, &updated_exponent);
 exponent = updated_exponent;
 return StrtofTrimmed(trimmed, exponent);
}

float StrtofTrimmed(Vector<const char> trimmed, int exponent) {
 DOUBLE_CONVERSION_ASSERT(trimmed.length() <= kMaxSignificantDecimalDigits);
 DOUBLE_CONVERSION_ASSERT(AssertTrimmedDigits(trimmed));

 double double_guess;
 bool is_correct = ComputeGuess(trimmed, exponent, &double_guess);

 float float_guess = SanitizedDoubletof(double_guess);
 if (float_guess == double_guess) {
   // This shortcut triggers for integer values.
   return float_guess;
 }

 // We must catch double-rounding. Say the double has been rounded up, and is
 // now a boundary of a float, and rounds up again. This is why we have to
 // look at previous too.
 // Example (in decimal numbers):
 //    input: 12349
 //    high-precision (4 digits): 1235
 //    low-precision (3 digits):
 //       when read from input: 123
 //       when rounded from high precision: 124.
 // To do this we simply look at the neighbors of the correct result and see
 // if they would round to the same float. If the guess is not correct we have
 // to look at four values (since two different doubles could be the correct
 // double).

 double double_next = Double(double_guess).NextDouble();
 double double_previous = Double(double_guess).PreviousDouble();

 float f1 = SanitizedDoubletof(double_previous);
 float f2 = float_guess;
 float f3 = SanitizedDoubletof(double_next);
 float f4;
 if (is_correct) {
   f4 = f3;
 } else {
   double double_next2 = Double(double_next).NextDouble();
   f4 = SanitizedDoubletof(double_next2);
 }
 (void) f2;  // Mark variable as used.
 DOUBLE_CONVERSION_ASSERT(f1 <= f2 && f2 <= f3 && f3 <= f4);

 // If the guess doesn't lie near a single-precision boundary we can simply
 // return its float-value.
 if (f1 == f4) {
   return float_guess;
 }

 DOUBLE_CONVERSION_ASSERT((f1 != f2 && f2 == f3 && f3 == f4) ||
        (f1 == f2 && f2 != f3 && f3 == f4) ||
        (f1 == f2 && f2 == f3 && f3 != f4));

 // guess and next are the two possible candidates (in the same way that
 // double_guess was the lower candidate for a double-precision guess).
 float guess = f1;
 float next = f4;
 DiyFp upper_boundary;
 if (guess == 0.0f) {
   float min_float = 1e-45f;
   upper_boundary = Double(static_cast<double>(min_float) / 2).AsDiyFp();
 } else {
   upper_boundary = Single(guess).UpperBoundary();
 }
 int comparison = CompareBufferWithDiyFp(trimmed, exponent, upper_boundary);
 if (comparison < 0) {
   return guess;
 } else if (comparison > 0) {
   return next;
 } else if ((Single(guess).Significand() & 1) == 0) {
   // Round towards even.
   return guess;
 } else {
   return next;
 }
}

}  // namespace double_conversion

// ICU PATCH: Close ICU namespace
U_NAMESPACE_END
#endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING