18b112d2025046f85ef7f6be087c6129c872ebad2Ben Murdoch// Copyright 2011 the V8 project authors. All rights reserved. 2b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch// Use of this source code is governed by a BSD-style license that can be 3b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch// found in the LICENSE file. 4a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 56ded16be15dd865a9b21ea304d5273c8be299c87Steve Block#include <limits.h> 6b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include <stdarg.h> 7b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include <cmath> 8b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 9b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/v8.h" 10a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 11b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/assert-scope.h" 12b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/conversions-inl.h" 13b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/conversions.h" 14b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/dtoa.h" 15b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/factory.h" 16b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/list-inl.h" 17b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/strtod.h" 18b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#include "src/utils.h" 19b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 20b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#ifndef _STLP_VENDOR_CSTD 21b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch// STLPort doesn't import fpclassify into the std namespace. 22b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochusing std::fpclassify; 23b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch#endif 24a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 25a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blocknamespace v8 { 26a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blocknamespace internal { 27a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 28a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 29b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochnamespace { 30b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 31b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch// C++-style iterator adaptor for StringCharacterStream 32b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch// (unlike C++ iterators the end-marker has different type). 33b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochclass StringCharacterStreamIterator { 34b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch public: 35b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch class EndMarker {}; 36b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 37b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch explicit StringCharacterStreamIterator(StringCharacterStream* stream); 38b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 39b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch uint16_t operator*() const; 40b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch void operator++(); 41b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch bool operator==(EndMarker const&) const { return end_; } 42b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch bool operator!=(EndMarker const& m) const { return !end_; } 43b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 44b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch private: 45b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch StringCharacterStream* const stream_; 46b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch uint16_t current_; 47b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch bool end_; 48b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch}; 49b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 50b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 51b8a8cc1952d61a2f3a2568848933943a543b5d3eBen MurdochStringCharacterStreamIterator::StringCharacterStreamIterator( 52b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch StringCharacterStream* stream) : stream_(stream) { 53b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch ++(*this); 54b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch} 55b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 56b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochuint16_t StringCharacterStreamIterator::operator*() const { 57b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch return current_; 58b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch} 59b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 60b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 61b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochvoid StringCharacterStreamIterator::operator++() { 62b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch end_ = !stream_->HasMore(); 63b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch if (!end_) { 64b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch current_ = stream_->GetNext(); 65b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch } 66b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch} 67b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch} // End anonymous namespace. 68b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 69b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 708b112d2025046f85ef7f6be087c6129c872ebad2Ben Murdochdouble StringToDouble(UnicodeCache* unicode_cache, 718b112d2025046f85ef7f6be087c6129c872ebad2Ben Murdoch const char* str, int flags, double empty_string_val) { 72b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch // We cast to const uint8_t* here to avoid instantiating the 73b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch // InternalStringToDouble() template for const char* as well. 74b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch const uint8_t* start = reinterpret_cast<const uint8_t*>(str); 75b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch const uint8_t* end = start + StrLength(str); 76b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch return InternalStringToDouble(unicode_cache, start, end, flags, 7744f0eee88ff00398ff7f715fab053374d808c90dSteve Block empty_string_val); 78a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 79a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 80a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 818b112d2025046f85ef7f6be087c6129c872ebad2Ben Murdochdouble StringToDouble(UnicodeCache* unicode_cache, 82b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch Vector<const uint8_t> str, 8380d68eab642096c1a48b6474d6ec33064b0ad1f5Kristian Monsen int flags, 8480d68eab642096c1a48b6474d6ec33064b0ad1f5Kristian Monsen double empty_string_val) { 85b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch // We cast to const uint8_t* here to avoid instantiating the 86b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch // InternalStringToDouble() template for const char* as well. 87b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch const uint8_t* start = reinterpret_cast<const uint8_t*>(str.start()); 88b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch const uint8_t* end = start + str.length(); 89b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch return InternalStringToDouble(unicode_cache, start, end, flags, 9044f0eee88ff00398ff7f715fab053374d808c90dSteve Block empty_string_val); 9180d68eab642096c1a48b6474d6ec33064b0ad1f5Kristian Monsen} 9280d68eab642096c1a48b6474d6ec33064b0ad1f5Kristian Monsen 93b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 94257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdochdouble StringToDouble(UnicodeCache* unicode_cache, 95257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch Vector<const uc16> str, 96257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch int flags, 97257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch double empty_string_val) { 98257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch const uc16* end = str.start() + str.length(); 99257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch return InternalStringToDouble(unicode_cache, str.start(), end, flags, 100257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch empty_string_val); 101257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch} 102257744e915dfc84d6d07a6b2accf8402d9ffc708Ben Murdoch 10380d68eab642096c1a48b6474d6ec33064b0ad1f5Kristian Monsen 104b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch// Converts a string into an integer. 105b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochdouble StringToInt(UnicodeCache* unicode_cache, 106b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch Vector<const uint8_t> vector, 107b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch int radix) { 108b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch return InternalStringToInt( 109b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch unicode_cache, vector.start(), vector.start() + vector.length(), radix); 110b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch} 111b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 112b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 113b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochdouble StringToInt(UnicodeCache* unicode_cache, 114b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch Vector<const uc16> vector, 115b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch int radix) { 116b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch return InternalStringToInt( 117b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch unicode_cache, vector.start(), vector.start() + vector.length(), radix); 118b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch} 119b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 120b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 121a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blockconst char* DoubleToCString(double v, Vector<char> buffer) { 122a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block switch (fpclassify(v)) { 1231e0659c275bb392c045087af4f6b0d7565cb3d77Steve Block case FP_NAN: return "NaN"; 1241e0659c275bb392c045087af4f6b0d7565cb3d77Steve Block case FP_INFINITE: return (v < 0.0 ? "-Infinity" : "Infinity"); 1251e0659c275bb392c045087af4f6b0d7565cb3d77Steve Block case FP_ZERO: return "0"; 126a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block default: { 1273fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch SimpleStringBuilder builder(buffer.start(), buffer.length()); 128a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int decimal_point; 129a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int sign; 13025f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen const int kV8DtoaBufferCapacity = kBase10MaximalLength + 1; 1318a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang char decimal_rep[kV8DtoaBufferCapacity]; 1326ded16be15dd865a9b21ea304d5273c8be299c87Steve Block int length; 13325f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen 1348a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang DoubleToAscii(v, DTOA_SHORTEST, 0, 1358a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang Vector<char>(decimal_rep, kV8DtoaBufferCapacity), 1368a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang &sign, &length, &decimal_point); 137a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 138a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (sign) builder.AddCharacter('-'); 139a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 140a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (length <= decimal_point && decimal_point <= 21) { 141a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // ECMA-262 section 9.8.1 step 6. 142a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString(decimal_rep); 143a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddPadding('0', decimal_point - length); 144a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 145a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } else if (0 < decimal_point && decimal_point <= 21) { 146a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // ECMA-262 section 9.8.1 step 7. 147a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddSubstring(decimal_rep, decimal_point); 148a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter('.'); 149a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString(decimal_rep + decimal_point); 150a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 151a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } else if (decimal_point <= 0 && decimal_point > -6) { 152a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // ECMA-262 section 9.8.1 step 8. 153a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString("0."); 154a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddPadding('0', -decimal_point); 155a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString(decimal_rep); 156a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 157a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } else { 158a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // ECMA-262 section 9.8.1 step 9 and 10 combined. 159a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter(decimal_rep[0]); 160a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (length != 1) { 161a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter('.'); 162a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString(decimal_rep + 1); 163a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 164a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter('e'); 165a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter((decimal_point >= 0) ? '+' : '-'); 166a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int exponent = decimal_point - 1; 167a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (exponent < 0) exponent = -exponent; 1683fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch builder.AddDecimalInteger(exponent); 169a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 1701e0659c275bb392c045087af4f6b0d7565cb3d77Steve Block return builder.Finalize(); 171a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 172a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 173a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 174a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 175a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 176a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blockconst char* IntToCString(int n, Vector<char> buffer) { 177a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block bool negative = false; 178a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (n < 0) { 179a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // We must not negate the most negative int. 180a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (n == kMinInt) return DoubleToCString(n, buffer); 181a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block negative = true; 182a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block n = -n; 183a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 184a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Build the string backwards from the least significant digit. 185a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int i = buffer.length(); 186a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block buffer[--i] = '\0'; 187a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block do { 188a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block buffer[--i] = '0' + (n % 10); 189a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block n /= 10; 190a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } while (n); 191a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (negative) buffer[--i] = '-'; 192a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block return buffer.start() + i; 193a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 194a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 195a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 196a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blockchar* DoubleToFixedCString(double value, int f) { 1973e5fa29ddb82551500b118e9bf37af3966277b70Teng-Hui Zhu const int kMaxDigitsBeforePoint = 21; 19825f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen const double kFirstNonFixed = 1e21; 19925f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen const int kMaxDigitsAfterPoint = 20; 200b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(f >= 0); 201b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(f <= kMaxDigitsAfterPoint); 202a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 203a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block bool negative = false; 204a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block double abs_value = value; 205a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (value < 0) { 206a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block abs_value = -value; 207a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block negative = true; 208a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 209a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 21025f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen // If abs_value has more than kMaxDigitsBeforePoint digits before the point 21125f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen // use the non-fixed conversion routine. 21225f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen if (abs_value >= kFirstNonFixed) { 213a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block char arr[100]; 214b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch Vector<char> buffer(arr, arraysize(arr)); 215a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block return StrDup(DoubleToCString(value, buffer)); 216a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 217a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 218a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Find a sufficiently precise decimal representation of n. 219a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int decimal_point; 220a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int sign; 2213e5fa29ddb82551500b118e9bf37af3966277b70Teng-Hui Zhu // Add space for the '\0' byte. 22225f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen const int kDecimalRepCapacity = 2233e5fa29ddb82551500b118e9bf37af3966277b70Teng-Hui Zhu kMaxDigitsBeforePoint + kMaxDigitsAfterPoint + 1; 22425f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen char decimal_rep[kDecimalRepCapacity]; 22525f6136652d8341ed047e7fc1a450af5bd218ea9Kristian Monsen int decimal_rep_length; 2268a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang DoubleToAscii(value, DTOA_FIXED, f, 2278a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang Vector<char>(decimal_rep, kDecimalRepCapacity), 2288a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang &sign, &decimal_rep_length, &decimal_point); 229a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 230a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Create a representation that is padded with zeros if needed. 231a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int zero_prefix_length = 0; 232a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int zero_postfix_length = 0; 233a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 234a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (decimal_point <= 0) { 235a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block zero_prefix_length = -decimal_point + 1; 236a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block decimal_point = 1; 237a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 238a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 239a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (zero_prefix_length + decimal_rep_length < decimal_point + f) { 240a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block zero_postfix_length = decimal_point + f - decimal_rep_length - 241a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block zero_prefix_length; 242a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 243a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 244a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block unsigned rep_length = 245a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block zero_prefix_length + decimal_rep_length + zero_postfix_length; 2463fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch SimpleStringBuilder rep_builder(rep_length + 1); 247a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block rep_builder.AddPadding('0', zero_prefix_length); 248a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block rep_builder.AddString(decimal_rep); 249a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block rep_builder.AddPadding('0', zero_postfix_length); 250a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block char* rep = rep_builder.Finalize(); 251a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 252a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Create the result string by appending a minus and putting in a 253a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // decimal point if needed. 254a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block unsigned result_size = decimal_point + f + 2; 2553fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch SimpleStringBuilder builder(result_size + 1); 256a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (negative) builder.AddCharacter('-'); 257a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddSubstring(rep, decimal_point); 258a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (f > 0) { 259a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter('.'); 260a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddSubstring(rep + decimal_point, f); 261a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 262a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block DeleteArray(rep); 263a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block return builder.Finalize(); 264a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 265a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 266a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 267a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blockstatic char* CreateExponentialRepresentation(char* decimal_rep, 268a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int exponent, 269a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block bool negative, 270a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int significant_digits) { 271a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block bool negative_exponent = false; 272a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (exponent < 0) { 273a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block negative_exponent = true; 274a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block exponent = -exponent; 275a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 276a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 277a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Leave room in the result for appending a minus, for a period, the 278a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // letter 'e', a minus or a plus depending on the exponent, and a 279a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // three digit exponent. 280a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block unsigned result_size = significant_digits + 7; 2813fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch SimpleStringBuilder builder(result_size + 1); 282a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 283a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (negative) builder.AddCharacter('-'); 284a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter(decimal_rep[0]); 285a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (significant_digits != 1) { 286a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter('.'); 287a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString(decimal_rep + 1); 288d0582a6c46733687d045e4188a1bcd0123c758a1Steve Block int rep_length = StrLength(decimal_rep); 289d0582a6c46733687d045e4188a1bcd0123c758a1Steve Block builder.AddPadding('0', significant_digits - rep_length); 290a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 291a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 292a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter('e'); 293a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter(negative_exponent ? '-' : '+'); 2943fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch builder.AddDecimalInteger(exponent); 295a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block return builder.Finalize(); 296a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 297a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 298a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 299a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blockchar* DoubleToExponentialCString(double value, int f) { 3000d5e116f6aee03185f237311a943491bb079a768Kristian Monsen const int kMaxDigitsAfterPoint = 20; 301a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // f might be -1 to signal that f was undefined in JavaScript. 302b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(f >= -1 && f <= kMaxDigitsAfterPoint); 303a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 304a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block bool negative = false; 305a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (value < 0) { 306a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block value = -value; 307a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block negative = true; 308a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 309a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 310a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Find a sufficiently precise decimal representation of n. 311a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int decimal_point; 312a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int sign; 3130d5e116f6aee03185f237311a943491bb079a768Kristian Monsen // f corresponds to the digits after the point. There is always one digit 3140d5e116f6aee03185f237311a943491bb079a768Kristian Monsen // before the point. The number of requested_digits equals hence f + 1. 3150d5e116f6aee03185f237311a943491bb079a768Kristian Monsen // And we have to add one character for the null-terminator. 3160d5e116f6aee03185f237311a943491bb079a768Kristian Monsen const int kV8DtoaBufferCapacity = kMaxDigitsAfterPoint + 1 + 1; 3170d5e116f6aee03185f237311a943491bb079a768Kristian Monsen // Make sure that the buffer is big enough, even if we fall back to the 3180d5e116f6aee03185f237311a943491bb079a768Kristian Monsen // shortest representation (which happens when f equals -1). 319b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(kBase10MaximalLength <= kMaxDigitsAfterPoint + 1); 3208a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang char decimal_rep[kV8DtoaBufferCapacity]; 3210d5e116f6aee03185f237311a943491bb079a768Kristian Monsen int decimal_rep_length; 3220d5e116f6aee03185f237311a943491bb079a768Kristian Monsen 323a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (f == -1) { 3248a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang DoubleToAscii(value, DTOA_SHORTEST, 0, 3258a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang Vector<char>(decimal_rep, kV8DtoaBufferCapacity), 3268a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang &sign, &decimal_rep_length, &decimal_point); 3278a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang f = decimal_rep_length - 1; 328a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } else { 3298a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang DoubleToAscii(value, DTOA_PRECISION, f + 1, 3308a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang Vector<char>(decimal_rep, kV8DtoaBufferCapacity), 3318a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang &sign, &decimal_rep_length, &decimal_point); 332a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 333b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(decimal_rep_length > 0); 334b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(decimal_rep_length <= f + 1); 335a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 336a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int exponent = decimal_point - 1; 337a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block char* result = 338a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block CreateExponentialRepresentation(decimal_rep, exponent, negative, f+1); 339a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 340a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block return result; 341a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 342a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 343a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 344a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blockchar* DoubleToPrecisionCString(double value, int p) { 3450d5e116f6aee03185f237311a943491bb079a768Kristian Monsen const int kMinimalDigits = 1; 3460d5e116f6aee03185f237311a943491bb079a768Kristian Monsen const int kMaximalDigits = 21; 347b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(p >= kMinimalDigits && p <= kMaximalDigits); 3480d5e116f6aee03185f237311a943491bb079a768Kristian Monsen USE(kMinimalDigits); 349a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 350a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block bool negative = false; 351a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (value < 0) { 352a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block value = -value; 353a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block negative = true; 354a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 355a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 356a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Find a sufficiently precise decimal representation of n. 357a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int decimal_point; 358a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int sign; 3590d5e116f6aee03185f237311a943491bb079a768Kristian Monsen // Add one for the terminating null character. 3600d5e116f6aee03185f237311a943491bb079a768Kristian Monsen const int kV8DtoaBufferCapacity = kMaximalDigits + 1; 3618a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang char decimal_rep[kV8DtoaBufferCapacity]; 3620d5e116f6aee03185f237311a943491bb079a768Kristian Monsen int decimal_rep_length; 3630d5e116f6aee03185f237311a943491bb079a768Kristian Monsen 3648a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang DoubleToAscii(value, DTOA_PRECISION, p, 3658a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang Vector<char>(decimal_rep, kV8DtoaBufferCapacity), 3668a31eba00023874d4a1dcdc5f411cc4336776874Shimeng (Simon) Wang &sign, &decimal_rep_length, &decimal_point); 367b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(decimal_rep_length <= p); 368a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 369a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int exponent = decimal_point - 1; 370a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 371a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block char* result = NULL; 372a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 373a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (exponent < -6 || exponent >= p) { 374a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block result = 375a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block CreateExponentialRepresentation(decimal_rep, exponent, negative, p); 376a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } else { 377a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Use fixed notation. 378a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // 379a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Leave room in the result for appending a minus, a period and in 380a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // the case where decimal_point is not positive for a zero in 381a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // front of the period. 382a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block unsigned result_size = (decimal_point <= 0) 383a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block ? -decimal_point + p + 3 384a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block : p + 2; 3853fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch SimpleStringBuilder builder(result_size + 1); 386a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (negative) builder.AddCharacter('-'); 387a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (decimal_point <= 0) { 388a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString("0."); 389a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddPadding('0', -decimal_point); 390a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddString(decimal_rep); 391a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddPadding('0', p - decimal_rep_length); 392a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } else { 393a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block const int m = Min(decimal_rep_length, decimal_point); 394a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddSubstring(decimal_rep, m); 395a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddPadding('0', decimal_point - decimal_rep_length); 396a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (decimal_point < p) { 397a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddCharacter('.'); 398a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block const int extra = negative ? 2 : 1; 399a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (decimal_rep_length > decimal_point) { 400d0582a6c46733687d045e4188a1bcd0123c758a1Steve Block const int len = StrLength(decimal_rep + decimal_point); 401a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block const int n = Min(len, p - (builder.position() - extra)); 402a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddSubstring(decimal_rep + decimal_point, n); 403a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 404a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddPadding('0', extra + (p - builder.position())); 405a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 406a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 407a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block result = builder.Finalize(); 408a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 409a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 410a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block return result; 411a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 412a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 413a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 414a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Blockchar* DoubleToRadixCString(double value, int radix) { 415b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(radix >= 2 && radix <= 36); 416a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 417a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Character array used for conversion. 418a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block static const char chars[] = "0123456789abcdefghijklmnopqrstuvwxyz"; 419a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 420a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Buffer for the integer part of the result. 1024 chars is enough 421a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // for max integer value in radix 2. We need room for a sign too. 422a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block static const int kBufferSize = 1100; 423a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block char integer_buffer[kBufferSize]; 424a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block integer_buffer[kBufferSize - 1] = '\0'; 425a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 426a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Buffer for the decimal part of the result. We only generate up 427a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // to kBufferSize - 1 chars for the decimal part. 428a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block char decimal_buffer[kBufferSize]; 429a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block decimal_buffer[kBufferSize - 1] = '\0'; 430a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 431a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Make sure the value is positive. 432a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block bool is_negative = value < 0.0; 433a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (is_negative) value = -value; 434a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 435a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Get the integer part and the decimal part. 436b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch double integer_part = std::floor(value); 437a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block double decimal_part = value - integer_part; 438a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 439a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Convert the integer part starting from the back. Always generate 440a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // at least one digit. 441a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int integer_pos = kBufferSize - 2; 442a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block do { 443b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch double remainder = std::fmod(integer_part, radix); 444b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch integer_buffer[integer_pos--] = chars[static_cast<int>(remainder)]; 445b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch integer_part -= remainder; 446a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block integer_part /= radix; 447a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } while (integer_part >= 1.0); 448a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Sanity check. 449b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DCHECK(integer_pos > 0); 450a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Add sign if needed. 451a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (is_negative) integer_buffer[integer_pos--] = '-'; 452a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 453a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Convert the decimal part. Repeatedly multiply by the radix to 454a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // generate the next char. Never generate more than kBufferSize - 1 455a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // chars. 456a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // 457a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // TODO(1093998): We will often generate a full decimal_buffer of 458a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // chars because hitting zero will often not happen. The right 459a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // solution would be to continue until the string representation can 460a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // be read back and yield the original value. To implement this 461a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // efficiently, we probably have to modify dtoa. 462a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int decimal_pos = 0; 463a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block while ((decimal_part > 0.0) && (decimal_pos < kBufferSize - 1)) { 464a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block decimal_part *= radix; 465a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block decimal_buffer[decimal_pos++] = 466b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch chars[static_cast<int>(std::floor(decimal_part))]; 467b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch decimal_part -= std::floor(decimal_part); 468a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block } 469a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block decimal_buffer[decimal_pos] = '\0'; 470a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 471a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Compute the result size. 472a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block int integer_part_size = kBufferSize - 2 - integer_pos; 473a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Make room for zero termination. 474a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block unsigned result_size = integer_part_size + decimal_pos; 475a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // If the number has a decimal part, leave room for the period. 476a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (decimal_pos > 0) result_size++; 477a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block // Allocate result and fill in the parts. 4783fb3ca8c7ca439d408449a395897395c0faae8d1Ben Murdoch SimpleStringBuilder builder(result_size + 1); 479a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddSubstring(integer_buffer + integer_pos + 1, integer_part_size); 480a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block if (decimal_pos > 0) builder.AddCharacter('.'); 481a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block builder.AddSubstring(decimal_buffer, decimal_pos); 482a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block return builder.Finalize(); 483a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} 484a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block 485b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 486b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdochdouble StringToDouble(UnicodeCache* unicode_cache, 487b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch String* string, 488b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch int flags, 489b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch double empty_string_val) { 490b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch DisallowHeapAllocation no_gc; 491b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch String::FlatContent flat = string->GetFlatContent(); 492b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch // ECMA-262 section 15.1.2.3, empty string is NaN 493b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch if (flat.IsOneByte()) { 494b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch return StringToDouble( 495b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch unicode_cache, flat.ToOneByteVector(), flags, empty_string_val); 496b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch } else { 497b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch return StringToDouble( 498b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch unicode_cache, flat.ToUC16Vector(), flags, empty_string_val); 499b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch } 500b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch} 501b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 502b8a8cc1952d61a2f3a2568848933943a543b5d3eBen Murdoch 503a7e24c173cf37484693b9abb38e494fa7bd7baebSteve Block} } // namespace v8::internal 504