1 // Copyright 2006-2008 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #ifndef V8_CONVERSIONS_H_ 29 #define V8_CONVERSIONS_H_ 30 31 namespace v8 { 32 namespace internal { 33 34 35 // The fast double-to-int conversion routine does not guarantee 36 // rounding towards zero. 37 // The result is unspecified if x is infinite or NaN, or if the rounded 38 // integer value is outside the range of type int. 39 static inline int FastD2I(double x); 40 41 42 static inline double FastI2D(int x) { 43 // There is no rounding involved in converting an integer to a 44 // double, so this code should compile to a few instructions without 45 // any FPU pipeline stalls. 46 return static_cast<double>(x); 47 } 48 49 50 static inline double FastUI2D(unsigned x) { 51 // There is no rounding involved in converting an unsigned integer to a 52 // double, so this code should compile to a few instructions without 53 // any FPU pipeline stalls. 54 return static_cast<double>(x); 55 } 56 57 58 // This function should match the exact semantics of ECMA-262 9.4. 59 static inline double DoubleToInteger(double x); 60 61 62 // This function should match the exact semantics of ECMA-262 9.5. 63 static inline int32_t DoubleToInt32(double x); 64 65 66 // This function should match the exact semantics of ECMA-262 9.6. 67 static inline uint32_t DoubleToUint32(double x) { 68 return static_cast<uint32_t>(DoubleToInt32(x)); 69 } 70 71 72 // Returns the value (0 .. 15) of a hexadecimal character c. 73 // If c is not a legal hexadecimal character, returns a value < 0. 74 int HexValue(uc32 c); 75 76 77 // Enumeration for allowing octals and ignoring junk when converting 78 // strings to numbers. 79 enum ConversionFlags { 80 NO_FLAGS = 0, 81 ALLOW_HEX = 1, 82 ALLOW_OCTALS = 2, 83 ALLOW_TRAILING_JUNK = 4 84 }; 85 86 87 // Convert from Number object to C integer. 88 static inline int32_t NumberToInt32(Object* number); 89 static inline uint32_t NumberToUint32(Object* number); 90 91 92 // Converts a string into a double value according to ECMA-262 9.3.1 93 double StringToDouble(const char* str, int flags, double empty_string_val = 0); 94 double StringToDouble(String* str, int flags, double empty_string_val = 0); 95 96 // Converts a string into an integer. 97 int StringToInt(String* str, int index, int radix, double* value); 98 int StringToInt(const char* str, int index, int radix, double* value); 99 100 // Converts a double to a string value according to ECMA-262 9.8.1. 101 // The buffer should be large enough for any floating point number. 102 // 100 characters is enough. 103 const char* DoubleToCString(double value, Vector<char> buffer); 104 105 // Convert an int to a null-terminated string. The returned string is 106 // located inside the buffer, but not necessarily at the start. 107 const char* IntToCString(int n, Vector<char> buffer); 108 109 // Additional number to string conversions for the number type. 110 // The caller is responsible for calling free on the returned pointer. 111 char* DoubleToFixedCString(double value, int f); 112 char* DoubleToExponentialCString(double value, int f); 113 char* DoubleToPrecisionCString(double value, int f); 114 char* DoubleToRadixCString(double value, int radix); 115 116 } } // namespace v8::internal 117 118 #endif // V8_CONVERSIONS_H_ 119
