1 // Copyright 2011 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include <cmath>
6
7 #include "include/v8stdint.h"
8 #include "src/checks.h"
9 #include "src/utils.h"
10
11 #include "src/dtoa.h"
12
13 #include "src/bignum-dtoa.h"
14 #include "src/double.h"
15 #include "src/fast-dtoa.h"
16 #include "src/fixed-dtoa.h"
17
18 namespace v8 {
19 namespace internal {
20
DtoaToBignumDtoaMode(DtoaMode dtoa_mode)21 static BignumDtoaMode DtoaToBignumDtoaMode(DtoaMode dtoa_mode) {
22 switch (dtoa_mode) {
23 case DTOA_SHORTEST: return BIGNUM_DTOA_SHORTEST;
24 case DTOA_FIXED: return BIGNUM_DTOA_FIXED;
25 case DTOA_PRECISION: return BIGNUM_DTOA_PRECISION;
26 default:
27 UNREACHABLE();
28 return BIGNUM_DTOA_SHORTEST; // To silence compiler.
29 }
30 }
31
32
DoubleToAscii(double v,DtoaMode mode,int requested_digits,Vector<char> buffer,int * sign,int * length,int * point)33 void DoubleToAscii(double v, DtoaMode mode, int requested_digits,
34 Vector<char> buffer, int* sign, int* length, int* point) {
35 ASSERT(!Double(v).IsSpecial());
36 ASSERT(mode == DTOA_SHORTEST || requested_digits >= 0);
37
38 if (Double(v).Sign() < 0) {
39 *sign = 1;
40 v = -v;
41 } else {
42 *sign = 0;
43 }
44
45 if (v == 0) {
46 buffer[0] = '0';
47 buffer[1] = '\0';
48 *length = 1;
49 *point = 1;
50 return;
51 }
52
53 if (mode == DTOA_PRECISION && requested_digits == 0) {
54 buffer[0] = '\0';
55 *length = 0;
56 return;
57 }
58
59 bool fast_worked;
60 switch (mode) {
61 case DTOA_SHORTEST:
62 fast_worked = FastDtoa(v, FAST_DTOA_SHORTEST, 0, buffer, length, point);
63 break;
64 case DTOA_FIXED:
65 fast_worked = FastFixedDtoa(v, requested_digits, buffer, length, point);
66 break;
67 case DTOA_PRECISION:
68 fast_worked = FastDtoa(v, FAST_DTOA_PRECISION, requested_digits,
69 buffer, length, point);
70 break;
71 default:
72 UNREACHABLE();
73 fast_worked = false;
74 }
75 if (fast_worked) return;
76
77 // If the fast dtoa didn't succeed use the slower bignum version.
78 BignumDtoaMode bignum_mode = DtoaToBignumDtoaMode(mode);
79 BignumDtoa(v, bignum_mode, requested_digits, buffer, length, point);
80 buffer[*length] = '\0';
81 }
82
83 } } // namespace v8::internal
84