Ben Murdoch | 589d697 | 2011-11-30 16:04:58 +0000 | [diff] [blame] | 1 | // Copyright 2011 the V8 project authors. All rights reserved. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 4 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 5 | #include <cmath> |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 6 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 7 | #include "src/base/logging.h" |
| 8 | #include "src/utils.h" |
Ben Murdoch | 589d697 | 2011-11-30 16:04:58 +0000 | [diff] [blame] | 9 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 10 | #include "src/dtoa.h" |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 11 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 12 | #include "src/bignum-dtoa.h" |
| 13 | #include "src/double.h" |
| 14 | #include "src/fast-dtoa.h" |
| 15 | #include "src/fixed-dtoa.h" |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 16 | |
| 17 | namespace v8 { |
| 18 | namespace internal { |
| 19 | |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 20 | static BignumDtoaMode DtoaToBignumDtoaMode(DtoaMode dtoa_mode) { |
| 21 | switch (dtoa_mode) { |
| 22 | case DTOA_SHORTEST: return BIGNUM_DTOA_SHORTEST; |
| 23 | case DTOA_FIXED: return BIGNUM_DTOA_FIXED; |
| 24 | case DTOA_PRECISION: return BIGNUM_DTOA_PRECISION; |
| 25 | default: |
| 26 | UNREACHABLE(); |
| 27 | return BIGNUM_DTOA_SHORTEST; // To silence compiler. |
| 28 | } |
| 29 | } |
| 30 | |
| 31 | |
| 32 | void DoubleToAscii(double v, DtoaMode mode, int requested_digits, |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 33 | Vector<char> buffer, int* sign, int* length, int* point) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame] | 34 | DCHECK(!Double(v).IsSpecial()); |
| 35 | DCHECK(mode == DTOA_SHORTEST || requested_digits >= 0); |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 36 | |
| 37 | if (Double(v).Sign() < 0) { |
| 38 | *sign = 1; |
| 39 | v = -v; |
| 40 | } else { |
| 41 | *sign = 0; |
| 42 | } |
| 43 | |
| 44 | if (v == 0) { |
| 45 | buffer[0] = '0'; |
| 46 | buffer[1] = '\0'; |
| 47 | *length = 1; |
| 48 | *point = 1; |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 49 | return; |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 50 | } |
| 51 | |
| 52 | if (mode == DTOA_PRECISION && requested_digits == 0) { |
| 53 | buffer[0] = '\0'; |
| 54 | *length = 0; |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 55 | return; |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 56 | } |
| 57 | |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 58 | bool fast_worked; |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 59 | switch (mode) { |
| 60 | case DTOA_SHORTEST: |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 61 | fast_worked = FastDtoa(v, FAST_DTOA_SHORTEST, 0, buffer, length, point); |
| 62 | break; |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 63 | case DTOA_FIXED: |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 64 | fast_worked = FastFixedDtoa(v, requested_digits, buffer, length, point); |
| 65 | break; |
Kristian Monsen | 0d5e116 | 2010-09-30 15:31:59 +0100 | [diff] [blame] | 66 | case DTOA_PRECISION: |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 67 | fast_worked = FastDtoa(v, FAST_DTOA_PRECISION, requested_digits, |
| 68 | buffer, length, point); |
| 69 | break; |
| 70 | default: |
| 71 | UNREACHABLE(); |
| 72 | fast_worked = false; |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 73 | } |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 74 | if (fast_worked) return; |
| 75 | |
| 76 | // If the fast dtoa didn't succeed use the slower bignum version. |
| 77 | BignumDtoaMode bignum_mode = DtoaToBignumDtoaMode(mode); |
| 78 | BignumDtoa(v, bignum_mode, requested_digits, buffer, length, point); |
| 79 | buffer[*length] = '\0'; |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 80 | } |
| 81 | |
| 82 | } } // namespace v8::internal |