Revert r4591

src/dtoa.h

-// 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.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef V8_DTOA_H_
-#define V8_DTOA_H_
-
-namespace v8 {
-namespace internal {
-
-enum DtoaMode {
-  // 0.9999999999999999 becomes 0.1
-  DTOA_SHORTEST,
-  // Fixed number of digits after the decimal point.
-  // For instance fixed(0.1, 4) becomes 0.1000
-  // If the input number is big, the output will be big.
-  DTOA_FIXED,
-  // Fixed number of digits (independent of the decimal point).
-  DTOA_PRECISION
-};
-
-// The maximal length of digits a double can have in base 10.
-// Note that DoubleToAscii null-terminates its input. So the given buffer should
-// be at least kBase10MaximalLength + 1 characters long.
-static const int kBase10MaximalLength = 17;
-
-// Converts the given double 'v' to ascii.
-// The result should be interpreted as buffer * 10^(point-length).
-//
-// The output depends on the given mode:
-//  - SHORTEST: produce the least amount of digits for which the internal
-//   identity requirement is still satisfied. If the digits are printed
-//   (together with the correct exponent) then reading this number will give
-//   'v' again. The buffer will choose the representation that is closest to
-//   'v'. If there are two at the same distance, than the one farther away
-//   from 0 is chosen (halfway cases - ending with 5 - are rounded up).
-//   In this mode the 'requested_digits' parameter is ignored.
-//  - FIXED: produces digits necessary to print a given number with
-//   'requested_digits' digits after the decimal point. The produced digits
-//   might be too short in which case the caller has to fill the gaps with '0's.
-//   Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2.
-//   Halfway cases are rounded towards +/-Infinity (away from 0). The call
-//   toFixed(0.15, 2) thus returns buffer="2", point=0.
-//   The returned buffer may contain digits that would be truncated from the
-//   shortest representation of the input.
-//  - PRECISION: produces 'requested_digits' where the first digit is not '0'.
-//   Even though the length of produced digits usually equals
-//   'requested_digits', the function is allowed to return fewer digits, in
-//   which case the caller has to fill the missing digits with '0's.
-//   Halfway cases are again rounded away from 0.
-// 'DoubleToAscii' expects the given buffer to be big enough to hold all digits
-// and a terminating null-character.
-bool DoubleToAscii(double v, DtoaMode mode, int requested_digits,
-                   Vector<char> buffer, int* sign, int* length, int* point);
-
-} }  // namespace v8::internal
-
-#endif  // V8_DTOA_H_