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// Copyright 2011 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <cmath>
#include "src/base/logging.h"
#include "src/utils.h"
#include "src/dtoa.h"
#include "src/bignum-dtoa.h"
#include "src/double.h"
#include "src/fast-dtoa.h"
#include "src/fixed-dtoa.h"
namespace v8 {
namespace internal {
static BignumDtoaMode DtoaToBignumDtoaMode(DtoaMode dtoa_mode) {
switch (dtoa_mode) {
case DTOA_SHORTEST: return BIGNUM_DTOA_SHORTEST;
case DTOA_FIXED: return BIGNUM_DTOA_FIXED;
case DTOA_PRECISION: return BIGNUM_DTOA_PRECISION;
default:
UNREACHABLE();
}
}
void DoubleToAscii(double v, DtoaMode mode, int requested_digits,
Vector<char> buffer, int* sign, int* length, int* point) {
DCHECK(!Double(v).IsSpecial());
DCHECK(mode == DTOA_SHORTEST || requested_digits >= 0);
if (Double(v).Sign() < 0) {
*sign = 1;
v = -v;
} else {
*sign = 0;
}
if (v == 0) {
buffer[0] = '0';
buffer[1] = '\0';
*length = 1;
*point = 1;
return;
}
if (mode == DTOA_PRECISION && requested_digits == 0) {
buffer[0] = '\0';
*length = 0;
return;
}
bool fast_worked;
switch (mode) {
case DTOA_SHORTEST:
fast_worked = FastDtoa(v, FAST_DTOA_SHORTEST, 0, buffer, length, point);
break;
case DTOA_FIXED:
fast_worked = FastFixedDtoa(v, requested_digits, buffer, length, point);
break;
case DTOA_PRECISION:
fast_worked = FastDtoa(v, FAST_DTOA_PRECISION, requested_digits,
buffer, length, point);
break;
default:
UNREACHABLE();
}
if (fast_worked) return;
// If the fast dtoa didn't succeed use the slower bignum version.
BignumDtoaMode bignum_mode = DtoaToBignumDtoaMode(mode);
BignumDtoa(v, bignum_mode, requested_digits, buffer, length, point);
buffer[*length] = '\0';
}
} // namespace internal
} // namespace v8
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