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The C and C++ Include Header Files
cat -n /usr/include/python3.14/internal/pycore_long.h
1 #ifndef Py_INTERNAL_LONG_H 2 #define Py_INTERNAL_LONG_H 3 #ifdef __cplusplus 4 extern "C" { 5 #endif 6 7 #ifndef Py_BUILD_CORE 8 # error "this header requires Py_BUILD_CORE define" 9 #endif 10 11 #include "pycore_bytesobject.h" // _PyBytesWriter 12 #include "pycore_runtime.h" // _Py_SINGLETON() 13 14 /* 15 * Default int base conversion size limitation: Denial of Service prevention. 16 * 17 * Chosen such that this isn't wildly slow on modern hardware and so that 18 * everyone's existing deployed numpy test suite passes before 19 * https://github.com/numpy/numpy/issues/22098 is widely available. 20 * 21 * $ python -m timeit -s 's = "1"*4300' 'int(s)' 22 * 2000 loops, best of 5: 125 usec per loop 23 * $ python -m timeit -s 's = "1"*4300; v = int(s)' 'str(v)' 24 * 1000 loops, best of 5: 311 usec per loop 25 * (zen2 cloud VM) 26 * 27 * 4300 decimal digits fits a ~14284 bit number. 28 */ 29 #define _PY_LONG_DEFAULT_MAX_STR_DIGITS 4300 30 /* 31 * Threshold for max digits check. For performance reasons int() and 32 * int.__str__() don't checks values that are smaller than this 33 * threshold. Acts as a guaranteed minimum size limit for bignums that 34 * applications can expect from CPython. 35 * 36 * % python -m timeit -s 's = "1"*640; v = int(s)' 'str(int(s))' 37 * 20000 loops, best of 5: 12 usec per loop 38 * 39 * "640 digits should be enough for anyone." - gps 40 * fits a ~2126 bit decimal number. 41 */ 42 #define _PY_LONG_MAX_STR_DIGITS_THRESHOLD 640 43 44 #if ((_PY_LONG_DEFAULT_MAX_STR_DIGITS != 0) && \ 45 (_PY_LONG_DEFAULT_MAX_STR_DIGITS < _PY_LONG_MAX_STR_DIGITS_THRESHOLD)) 46 # error "_PY_LONG_DEFAULT_MAX_STR_DIGITS smaller than threshold." 47 #endif 48 49 /* runtime lifecycle */ 50 51 extern PyStatus _PyLong_InitTypes(PyInterpreterState *); 52 extern void _PyLong_FiniTypes(PyInterpreterState *interp); 53 54 55 /* other API */ 56 57 PyAPI_FUNC(void) _PyLong_ExactDealloc(PyObject *self); 58 59 #define _PyLong_SMALL_INTS _Py_SINGLETON(small_ints) 60 61 // _PyLong_GetZero() and _PyLong_GetOne() must always be available 62 // _PyLong_FromUnsignedChar must always be available 63 #if _PY_NSMALLPOSINTS < 257 64 # error "_PY_NSMALLPOSINTS must be greater than or equal to 257" 65 #endif 66 67 #define _PY_IS_SMALL_INT(val) \ 68 (-_PY_NSMALLNEGINTS <= (val) && (val) < _PY_NSMALLPOSINTS) 69 70 // Return a reference to the immortal zero singleton. 71 // The function cannot return NULL. 72 static inline PyObject* _PyLong_GetZero(void) 73 { return (PyObject *)&_PyLong_SMALL_INTS[_PY_NSMALLNEGINTS]; } 74 75 // Return a reference to the immortal one singleton. 76 // The function cannot return NULL. 77 static inline PyObject* _PyLong_GetOne(void) 78 { return (PyObject *)&_PyLong_SMALL_INTS[_PY_NSMALLNEGINTS+1]; } 79 80 static inline PyObject* _PyLong_FromUnsignedChar(unsigned char i) 81 { 82 return (PyObject *)&_PyLong_SMALL_INTS[_PY_NSMALLNEGINTS+i]; 83 } 84 85 // _PyLong_Frexp returns a double x and an exponent e such that the 86 // true value is approximately equal to x * 2**e. x is 87 // 0.0 if and only if the input is 0 (in which case, e and x are both 88 // zeroes); otherwise, 0.5 <= abs(x) < 1.0. 89 // Always successful. 90 // 91 // Export for 'math' shared extension 92 PyAPI_DATA(double) _PyLong_Frexp(PyLongObject *a, int64_t *e); 93 94 extern PyObject* _PyLong_FromBytes(const char *, Py_ssize_t, int); 95 96 // _PyLong_DivmodNear. Given integers a and b, compute the nearest 97 // integer q to the exact quotient a / b, rounding to the nearest even integer 98 // in the case of a tie. Return (q, r), where r = a - q*b. The remainder r 99 // will satisfy abs(r) <= abs(b)/2, with equality possible only if q is 100 // even. 101 // 102 // Export for '_datetime' shared extension. 103 PyAPI_DATA(PyObject*) _PyLong_DivmodNear(PyObject *, PyObject *); 104 105 // _PyLong_Format: Convert the long to a string object with given base, 106 // appending a base prefix of 0[box] if base is 2, 8 or 16. 107 // Export for '_tkinter' shared extension. 108 PyAPI_DATA(PyObject*) _PyLong_Format(PyObject *obj, int base); 109 110 // Export for 'math' shared extension 111 PyAPI_DATA(PyObject*) _PyLong_Rshift(PyObject *, int64_t); 112 113 // Export for 'math' shared extension 114 PyAPI_DATA(PyObject*) _PyLong_Lshift(PyObject *, int64_t); 115 116 PyAPI_FUNC(PyObject*) _PyLong_Add(PyLongObject *left, PyLongObject *right); 117 PyAPI_FUNC(PyObject*) _PyLong_Multiply(PyLongObject *left, PyLongObject *right); 118 PyAPI_FUNC(PyObject*) _PyLong_Subtract(PyLongObject *left, PyLongObject *right); 119 120 // Export for 'binascii' shared extension. 121 PyAPI_DATA(unsigned char) _PyLong_DigitValue[256]; 122 123 /* Format the object based on the format_spec, as defined in PEP 3101 124 (Advanced String Formatting). */ 125 extern int _PyLong_FormatAdvancedWriter( 126 _PyUnicodeWriter *writer, 127 PyObject *obj, 128 PyObject *format_spec, 129 Py_ssize_t start, 130 Py_ssize_t end); 131 132 extern int _PyLong_FormatWriter( 133 _PyUnicodeWriter *writer, 134 PyObject *obj, 135 int base, 136 int alternate); 137 138 extern char* _PyLong_FormatBytesWriter( 139 _PyBytesWriter *writer, 140 char *str, 141 PyObject *obj, 142 int base, 143 int alternate); 144 145 // Argument converters used by Argument Clinic 146 147 // Export for 'select' shared extension (Argument Clinic code) 148 PyAPI_FUNC(int) _PyLong_UnsignedShort_Converter(PyObject *, void *); 149 150 // Export for '_testclinic' shared extension (Argument Clinic code) 151 PyAPI_FUNC(int) _PyLong_UnsignedInt_Converter(PyObject *, void *); 152 153 // Export for '_blake2' shared extension (Argument Clinic code) 154 PyAPI_FUNC(int) _PyLong_UnsignedLong_Converter(PyObject *, void *); 155 156 // Export for '_blake2' shared extension (Argument Clinic code) 157 PyAPI_FUNC(int) _PyLong_UnsignedLongLong_Converter(PyObject *, void *); 158 159 // Export for '_testclinic' shared extension (Argument Clinic code) 160 PyAPI_FUNC(int) _PyLong_Size_t_Converter(PyObject *, void *); 161 162 PyAPI_FUNC(int) _PyLong_UInt8_Converter(PyObject *, void *); 163 PyAPI_FUNC(int) _PyLong_UInt16_Converter(PyObject *, void *); 164 PyAPI_FUNC(int) _PyLong_UInt32_Converter(PyObject *, void *); 165 PyAPI_FUNC(int) _PyLong_UInt64_Converter(PyObject *, void *); 166 167 /* Long value tag bits: 168 * 0-1: Sign bits value = (1-sign), ie. negative=2, positive=0, zero=1. 169 * 2: Set to 1 for the small ints 170 * 3+ Unsigned digit count 171 */ 172 #define SIGN_MASK 3 173 #define SIGN_ZERO 1 174 #define SIGN_NEGATIVE 2 175 #define NON_SIZE_BITS 3 176 #define IMMORTALITY_BIT_MASK (1 << 2) 177 178 /* The functions _PyLong_IsCompact and _PyLong_CompactValue are defined 179 * in Include/cpython/longobject.h, since they need to be inline. 180 * 181 * "Compact" values have at least one bit to spare, 182 * so that addition and subtraction can be performed on the values 183 * without risk of overflow. 184 * 185 * The inline functions need tag bits. 186 * For readability, rather than do `#define SIGN_MASK _PyLong_SIGN_MASK` 187 * we define them to the numbers in both places and then assert that 188 * they're the same. 189 */ 190 #if SIGN_MASK != _PyLong_SIGN_MASK 191 # error "SIGN_MASK does not match _PyLong_SIGN_MASK" 192 #endif 193 #if NON_SIZE_BITS != _PyLong_NON_SIZE_BITS 194 # error "NON_SIZE_BITS does not match _PyLong_NON_SIZE_BITS" 195 #endif 196 197 /* All *compact" values are guaranteed to fit into 198 * a Py_ssize_t with at least one bit to spare. 199 * In other words, for 64 bit machines, compact 200 * will be signed 63 (or fewer) bit values 201 */ 202 203 /* Return 1 if the argument is compact int */ 204 static inline int 205 _PyLong_IsNonNegativeCompact(const PyLongObject* op) { 206 assert(PyLong_Check(op)); 207 return ((op->long_value.lv_tag & ~IMMORTALITY_BIT_MASK) <= (1 << NON_SIZE_BITS)); 208 } 209 210 211 static inline int 212 _PyLong_BothAreCompact(const PyLongObject* a, const PyLongObject* b) { 213 assert(PyLong_Check(a)); 214 assert(PyLong_Check(b)); 215 return (a->long_value.lv_tag | b->long_value.lv_tag) < (2 << NON_SIZE_BITS); 216 } 217 218 static inline bool 219 _PyLong_IsZero(const PyLongObject *op) 220 { 221 return (op->long_value.lv_tag & SIGN_MASK) == SIGN_ZERO; 222 } 223 224 static inline bool 225 _PyLong_IsNegative(const PyLongObject *op) 226 { 227 return (op->long_value.lv_tag & SIGN_MASK) == SIGN_NEGATIVE; 228 } 229 230 static inline bool 231 _PyLong_IsPositive(const PyLongObject *op) 232 { 233 return (op->long_value.lv_tag & SIGN_MASK) == 0; 234 } 235 236 /* Return true if the argument is a small int */ 237 static inline bool 238 _PyLong_IsSmallInt(const PyLongObject *op) 239 { 240 assert(PyLong_Check(op)); 241 bool is_small_int = (op->long_value.lv_tag & IMMORTALITY_BIT_MASK) != 0; 242 assert(PyLong_CheckExact(op) || (!is_small_int)); 243 assert(_Py_IsImmortal(op) || (!is_small_int)); 244 assert((_PyLong_IsCompact(op) 245 && _PY_IS_SMALL_INT(_PyLong_CompactValue(op))) 246 || (!is_small_int)); 247 return is_small_int; 248 } 249 250 static inline Py_ssize_t 251 _PyLong_DigitCount(const PyLongObject *op) 252 { 253 assert(PyLong_Check(op)); 254 return (Py_ssize_t)(op->long_value.lv_tag >> NON_SIZE_BITS); 255 } 256 257 /* Equivalent to _PyLong_DigitCount(op) * _PyLong_NonCompactSign(op) */ 258 static inline Py_ssize_t 259 _PyLong_SignedDigitCount(const PyLongObject *op) 260 { 261 assert(PyLong_Check(op)); 262 Py_ssize_t sign = 1 - (op->long_value.lv_tag & SIGN_MASK); 263 return sign * (Py_ssize_t)(op->long_value.lv_tag >> NON_SIZE_BITS); 264 } 265 266 static inline int 267 _PyLong_CompactSign(const PyLongObject *op) 268 { 269 assert(PyLong_Check(op)); 270 assert(_PyLong_IsCompact((PyLongObject *)op)); 271 return 1 - (op->long_value.lv_tag & SIGN_MASK); 272 } 273 274 static inline int 275 _PyLong_NonCompactSign(const PyLongObject *op) 276 { 277 assert(PyLong_Check(op)); 278 assert(!_PyLong_IsCompact((PyLongObject *)op)); 279 return 1 - (op->long_value.lv_tag & SIGN_MASK); 280 } 281 282 /* Do a and b have the same sign? */ 283 static inline int 284 _PyLong_SameSign(const PyLongObject *a, const PyLongObject *b) 285 { 286 return (a->long_value.lv_tag & SIGN_MASK) == (b->long_value.lv_tag & SIGN_MASK); 287 } 288 289 #define TAG_FROM_SIGN_AND_SIZE(sign, size) \ 290 ((uintptr_t)(1 - (sign)) | ((uintptr_t)(size) << NON_SIZE_BITS)) 291 292 static inline void 293 _PyLong_SetSignAndDigitCount(PyLongObject *op, int sign, Py_ssize_t size) 294 { 295 assert(size >= 0); 296 assert(-1 <= sign && sign <= 1); 297 assert(sign != 0 || size == 0); 298 op->long_value.lv_tag = TAG_FROM_SIGN_AND_SIZE(sign, size); 299 } 300 301 static inline void 302 _PyLong_SetDigitCount(PyLongObject *op, Py_ssize_t size) 303 { 304 assert(size >= 0); 305 op->long_value.lv_tag = (((size_t)size) << NON_SIZE_BITS) | (op->long_value.lv_tag & SIGN_MASK); 306 } 307 308 #define NON_SIZE_MASK ~(uintptr_t)((1 << NON_SIZE_BITS) - 1) 309 310 static inline void 311 _PyLong_FlipSign(PyLongObject *op) 312 { 313 assert(!_PyLong_IsSmallInt(op)); 314 unsigned int flipped_sign = 2 - (op->long_value.lv_tag & SIGN_MASK); 315 op->long_value.lv_tag &= NON_SIZE_MASK; 316 op->long_value.lv_tag |= flipped_sign; 317 } 318 319 #define _PyLong_DIGIT_INIT(val) \ 320 { \ 321 .ob_base = _PyObject_HEAD_INIT(&PyLong_Type), \ 322 .long_value = { \ 323 .lv_tag = TAG_FROM_SIGN_AND_SIZE( \ 324 (val) == 0 ? 0 : ((val) < 0 ? -1 : 1), \ 325 (val) == 0 ? 0 : 1) | IMMORTALITY_BIT_MASK, \ 326 { ((val) >= 0 ? (val) : -(val)) }, \ 327 } \ 328 } 329 330 #define _PyLong_FALSE_TAG TAG_FROM_SIGN_AND_SIZE(0, 0) 331 #define _PyLong_TRUE_TAG TAG_FROM_SIGN_AND_SIZE(1, 1) 332 333 #ifdef __cplusplus 334 } 335 #endif 336 #endif /* !Py_INTERNAL_LONG_H */
