• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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     static JSTaggedValue DoubleToString(JSThread *thread, double number, int radix);
130     static bool IsEmptyString(const uint8_t *start, const uint8_t *end);
131     static JSHandle<EcmaString> IntToEcmaString(const JSThread *thread, int number);
132     static JSHandle<EcmaString> DoubleToEcmaString(const JSThread *thread, double d);
133     static uint32_t ToCharCode(uint32_t number);
134     static JSTaggedValue Int32ToString(JSThread *thread, int32_t number, uint32_t radix);
135     static JSHandle<EcmaString> NumberToString(const JSThread *thread, JSTaggedValue number);
136     static double TruncateDouble(double d);
137     static int64_t DoubleToInt64(double d);
138     static bool IsDigitalString(const uint8_t *start, const uint8_t *end);
139     static int StringToInt(const uint8_t *start, const uint8_t *end);
140     static std::pair<bool, JSTaggedNumber> FastStringToNumber(const uint8_t *start,
141         const uint8_t *end, JSTaggedValue string);
142     static double StringToDouble(const uint8_t *start, const uint8_t *end, uint8_t radix, uint32_t flags = NO_FLAGS);
143     static int32_t DoubleToInt(double d, size_t bits);
144     static int32_t DoubleInRangeInt32(double d);
145     static JSTaggedValue StringToDoubleWithRadix(const uint8_t *start, const uint8_t *end, int radix, bool *negative);
146     static CString IntToString(int number);
147     static CString IntegerToString(double number, int radix);
148     static JSTaggedValue StringToBigInt(JSThread *thread, JSHandle<JSTaggedValue> strVal);
149     static JSTaggedValue DoubleToExponential(JSThread *thread, double number, int digit);
150     static JSTaggedValue DoubleToASCII(JSThread *thread, double valueNumber, int digits, int flags);
151     static void DoubleToASCIIWithFlag(std::string& buf, double valueNumber, int digits, int flags);
152     static void ToASCIIWithNegative(std::string& tmpbuf, int digitNumber, int n, const std::string& buf);
153     static void ToASCIIWithGreatThanZero(std::string& tmpbuf, int digitNumber, int number, const std::string& buf);
154 private:
155     static char Carry(char current, int radix);
156     static double Strtod(const char *str, int exponent, uint8_t radix);
157     static bool GotoNonspace(uint8_t **ptr, const uint8_t *end);
158     static void GetBase(double d, int digits, int *decimalPoint, char *buf, char *bufTmp, int size);
159     static int GetMinmumDigits(double d, int *decimalPoint, char *buf);
160     static int CustomEcvt(double valueNumber, int digits, int *decimalPoint, std::string& buf,
161                           bool isFixed, int *sign);
162     static void CustomFcvt(std::string& buf, int bufSize, double valueNumber, int digits);
163     static int CustomFcvtHelper(std::string& buf, int bufSize, double valueNumber, int digits, int roundingMode);
164     static void GetBaseForRoundingMode(double valueNumber, int digitNumber, int *decimalPoint, std::string& buf,
165                 std::string& buf1, int buf1Size, int roundingMode, int *sign);
166     static void CustomEcvtIsFixed(double &valueNumber, int &digits, int *decimalPoint, std::string& buf, int *sign);
167 };
168 
169 // This class is used to generate 0~1 uniform distribution pseudo-random numbers.
170 // It uses a 64-bit seed which is current timestamp to generate state value.
171 // The value is used in xorshift64* random generator to generate result.
172 class RandomGenerator {
173 public:
174     static void InitRandom();
175     static double NextDouble();
176     static int32_t GenerateIdentityHash();
177     static int32_t Next(int bits);
178 
179 private:
180     static uint64_t XorShift64(uint64_t *pVal);
181     static double ToDouble(uint64_t state);
182 
183 private:
184     static thread_local uint64_t randomState_;
185 };
186 }  // namespace panda::ecmascript::base
187 #endif  // ECMASCRIPT_BASE_NUMBER_HELPER_H
188