1 /* 2 * Copyright (c) 2021 Huawei Device Co., Ltd. 3 * Licensed under the Apache License, Version 2.0 (the "License"); 4 * you may not use this file except in compliance with the License. 5 * You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software 10 * distributed under the License is distributed on an "AS IS" BASIS, 11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 * See the License for the specific language governing permissions and 13 * limitations under the License. 14 */ 15 16 #ifndef ECMASCRIPT_BASE_NUMBER_HELPER_H 17 #define ECMASCRIPT_BASE_NUMBER_HELPER_H 18 19 #include <cstdint> 20 21 #include "ecmascript/ecma_string.h" 22 #include "ecmascript/js_tagged_value.h" 23 24 namespace panda::ecmascript::base { 25 constexpr double MIN_RADIX = 2; 26 constexpr double MAX_RADIX = 36; 27 constexpr double MIN_FRACTION = 0; 28 constexpr double MAX_FRACTION = 100; 29 30 // Coversion flags 31 static constexpr uint32_t NO_FLAGS = 0U; 32 static constexpr uint32_t ALLOW_BINARY = 1U << 0U; 33 static constexpr uint32_t ALLOW_OCTAL = 1U << 1U; 34 static constexpr uint32_t ALLOW_HEX = 1U << 2U; 35 static constexpr uint32_t IGNORE_TRAILING = 1U << 3U; 36 37 static constexpr char HALFCHAR = '5'; 38 static constexpr uint32_t MAX_PRECISION = 16; 39 static constexpr uint8_t BINARY = 2; 40 static constexpr uint8_t OCTAL = 8; 41 static constexpr uint8_t DECIMAL = 10; 42 static constexpr uint8_t HEXADECIMAL = 16; 43 static constexpr double HALF = 0.5; 44 static constexpr double EPSILON = std::numeric_limits<double>::epsilon(); 45 static constexpr int64_t MAX_SAFE_INTEGER = 9007199254740991; 46 static constexpr double MAX_VALUE = std::numeric_limits<double>::max(); 47 static constexpr double MIN_VALUE = std::numeric_limits<double>::min(); 48 static constexpr double POSITIVE_INFINITY = std::numeric_limits<double>::infinity(); 49 static constexpr double NAN_VALUE = std::numeric_limits<double>::quiet_NaN(); 50 static constexpr uint64_t MAX_UINT64_VALUE = std::numeric_limits<uint64_t>::max(); 51 static constexpr int MAX_INT_VALUE = std::numeric_limits<int>::max(); 52 53 // Helper defines for double 54 static constexpr int DOUBLE_MAX_PRECISION = 17; 55 static constexpr int DOUBLE_EXPONENT_BIAS = 0x3FF; 56 static constexpr size_t DOUBLE_SIGNIFICAND_SIZE = 52; 57 static constexpr uint64_t DOUBLE_SIGN_MASK = 0x8000000000000000ULL; 58 static constexpr uint64_t DOUBLE_EXPONENT_MASK = 0x7FFULL << DOUBLE_SIGNIFICAND_SIZE; 59 static constexpr uint64_t DOUBLE_SIGNIFICAND_MASK = 0x000FFFFFFFFFFFFFULL; 60 static constexpr uint64_t DOUBLE_HIDDEN_BIT = 1ULL << DOUBLE_SIGNIFICAND_SIZE; 61 static constexpr int32_t MINUS_ZERO_LOBITS = static_cast<int32_t>(0); 62 static constexpr int32_t MINUS_ZERO_HIBITS = static_cast<int32_t>(1) << 31; 63 static constexpr int64_t MINUS_ZERO_BITS = (static_cast<uint64_t>(MINUS_ZERO_HIBITS) << 32) | MINUS_ZERO_LOBITS; 64 static constexpr size_t INT64_BITS = 64; 65 static constexpr size_t INT32_BITS = 32; 66 static constexpr size_t INT16_BITS = 16; 67 static constexpr size_t INT8_BITS = 8; 68 static constexpr size_t JS_DTOA_BUF_SIZE = 128; 69 70 // Max number of hexadecimal digits to display an integer 71 static constexpr size_t INT64_HEX_DIGITS = INT64_BITS / 4; 72 static constexpr size_t INT32_HEX_DIGITS = INT32_BITS / 4; 73 static constexpr size_t INT16_HEX_DIGITS = INT16_BITS / 4; 74 static constexpr size_t INT8_HEX_DIGITS = INT8_BITS / 4; 75 76 static constexpr int EXPONENTBIAS = DOUBLE_EXPONENT_BIAS + DOUBLE_SIGNIFICAND_SIZE; 77 static constexpr int kDENORMAL = -EXPONENTBIAS + 1; 78 static constexpr uint64_t kINFINITY = 0x7FF0'0000'0000'0000; 79 80 // help defines for random 81 static constexpr int RIGHT12 = 12; 82 static constexpr int SECONDS_TO_SUBTLE = 1000000; 83 static constexpr int RIGHT27 = 27; 84 static constexpr int LEFT25 = 25; 85 static constexpr uint64_t GET_MULTIPLY = 0x2545F4914F6CDD1D; 86 // Exponent bits for double value between [1.0, 2.0) 87 static constexpr uint64_t EXPONENTBITS_RANGE_IN_ONE_AND_TWO = 0x3FF0000000000000; 88 89 // Special Value for Hole in ElementsKind 90 static constexpr uint64_t SPECIAL_HOLE = 0xFFFE000000000001; 91 92 // Special Value for Hole in ElementsKind 93 static constexpr uint32_t PGO_POLY_INLINE_REP = 0x7FFFFFFF; 94 95 // 96 static constexpr int MAX_DIGITS = 21; 97 static constexpr int MIN_DIGITS = -6; 98 99 // NumberFormat type 100 static constexpr int VAR_FORMAT = 0; 101 static constexpr int FIXED_FORMAT = 1; 102 static constexpr int FRAC_FORMAT = 2; 103 static constexpr int FORCE_FORMAT = 4; 104 105 // means add the point char to buf 106 static constexpr int POINT_INDEX = 3; 107 static constexpr int DECIMAL_INDEX = 2; 108 109 class NumberHelper { 110 public: GetNaN()111 static inline JSTaggedType GetNaN() 112 { 113 return JSTaggedValue(NAN_VALUE).GetRawData(); 114 } 115 116 static inline JSTaggedType GetPositiveInfinity() 117 { 118 return JSTaggedValue(POSITIVE_INFINITY).GetRawData(); 119 } 120 121 static bool IsFinite(JSTaggedValue number) 122 { 123 return number.IsInt() || (number.IsDouble() && std::isfinite(number.GetDouble())); 124 } 125 static bool IsNaN(JSTaggedValue number) 126 { 127 return number.IsDouble() && std::isnan(number.GetDouble()); 128 } 129 130 static bool inline IsDenormal(uint64_t x) 131 { 132 return (x & kINFINITY) == 0; 133 } 134 135 static int inline Exponent(double x) 136 { 137 uint64_t value = base::bit_cast<uint64_t>(x); 138 if (IsDenormal(value)) { 139 return kDENORMAL; 140 } 141 int biased = static_cast<int>((value & kINFINITY) >> DOUBLE_SIGNIFICAND_SIZE); 142 return biased - EXPONENTBIAS; 143 } 144 145 static uint64_t inline Significand(double x) 146 { 147 uint64_t value = base::bit_cast<uint64_t>(x); 148 uint64_t significand = value & DOUBLE_SIGNIFICAND_MASK; 149 if (!IsDenormal(value)) { 150 return significand + DOUBLE_HIDDEN_BIT; 151 } else { 152 return significand; 153 } 154 } 155 156 static bool inline IsSafeIntegerNumber(double d) 157 { 158 double number = TruncateDouble(d); 159 return (number == d) && std::abs(d) <= MAX_SAFE_INTEGER; 160 } 161 162 static JSTaggedValue DoubleToString(JSThread *thread, double number, int radix); 163 static bool IsEmptyString(const uint8_t *start, const uint8_t *end); 164 static JSHandle<EcmaString> IntToEcmaString(const JSThread *thread, int number); 165 static JSHandle<EcmaString> DoubleToEcmaString(const JSThread *thread, double d); 166 static uint32_t ToCharCode(uint32_t number); 167 static JSTaggedValue Int32ToString(JSThread *thread, int32_t number, uint32_t radix); 168 static JSHandle<EcmaString> NumberToString(const JSThread *thread, JSTaggedValue number); 169 static double PUBLIC_API TruncateDouble(double d); 170 static int64_t DoubleToInt64(double d); 171 static bool IsDigitalString(const uint8_t *start, const uint8_t *end); 172 static int StringToInt(const uint8_t *start, const uint8_t *end); 173 static std::pair<bool, JSTaggedNumber> FastStringToNumber(const uint8_t *start, 174 const uint8_t *end, JSTaggedValue string); 175 static double StringToDouble(const uint8_t *start, const uint8_t *end, uint8_t radix, uint32_t flags = NO_FLAGS); 176 static int32_t DoubleToInt(double d, size_t bits); 177 static int32_t PUBLIC_API DoubleInRangeInt32(double d); 178 static JSTaggedValue StringToNumber(EcmaString *string, int32_t radix); 179 static JSTaggedValue StringToDoubleWithRadix(const uint8_t *start, const uint8_t *end, int radix, bool *negative); 180 static CString IntToString(int number); 181 static CString IntegerToString(double number, int radix); 182 static JSTaggedValue PUBLIC_API StringToBigInt(JSThread *thread, JSHandle<JSTaggedValue> strVal); 183 static JSTaggedValue DoubleToExponential(JSThread *thread, double number, int digit); 184 static JSTaggedValue DoubleToASCII(JSThread *thread, double valueNumber, int digits, int flags); 185 static JSTaggedValue DoubleToFixedString(JSThread *thread, double valueNumber, int digits); 186 static JSTaggedValue DoubleToPrecisionString(JSThread *thread, double valueNumber, int digits); 187 static void DoubleToASCIIWithFlag(std::string& buf, double valueNumber, int digits, int flags); 188 static void ToASCIIWithNegative(std::string& tmpbuf, int digitNumber, int n, const std::string& buf); 189 static void ToASCIIWithGreatThanZero(std::string& tmpbuf, int digitNumber, int number, const std::string& buf); 190 static bool StringToInt64(const std::string& str, int64_t& value); 191 private: 192 static char Carry(char current, int radix); 193 static double Strtod(const char *str, int exponent, uint8_t radix); 194 static bool GotoNonspace(uint8_t **ptr, const uint8_t *end); 195 static void GetBase(double d, int digits, int *decimalPoint, char *buf, char *bufTmp, int size); 196 static int GetMinmumDigits(double d, int *decimalPoint, char *buf); 197 static int CustomEcvt(double valueNumber, int digits, int *decimalPoint, std::string& buf, 198 bool isFixed, int *sign); 199 static void CustomFcvt(std::string& buf, int bufSize, double valueNumber, int digits); 200 static int CustomFcvtHelper(std::string& buf, int bufSize, double valueNumber, int digits, int roundingMode); 201 static void GetBaseForRoundingMode(double valueNumber, int digitNumber, int *decimalPoint, std::string& buf, 202 std::string& buf1, int buf1Size, int roundingMode, int *sign); 203 static void CustomEcvtIsFixed(double &valueNumber, int &digits, int *decimalPoint, std::string& buf, int *sign); 204 }; 205 206 // This class is used to generate 0~1 uniform distribution pseudo-random numbers. 207 // It uses a 64-bit seed which is current timestamp to generate state value. 208 // The value is used in xorshift64* random generator to generate result. 209 class RandomGenerator { 210 public: 211 static void InitRandom(JSThread *thread); 212 static double NextDouble(); 213 static int32_t GenerateIdentityHash(); 214 static int32_t Next(int bits); 215 216 private: 217 static uint64_t XorShift64(uint64_t *pVal); 218 static double ToDouble(uint64_t state); 219 220 private: 221 static thread_local uint64_t randomState_; 222 }; 223 } // namespace panda::ecmascript::base 224 #endif // ECMASCRIPT_BASE_NUMBER_HELPER_H 225