UnrealEnginePython/android/python35/include/longintrepr.h at develop · breezonto/UnrealEnginePython · GitHub

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#ifndef Py_LIMITED_API

#ifndef Py_LONGINTREPR_H

#define Py_LONGINTREPR_H

#ifdef __cplusplus

extern "C" {

#endif

/* This is published for the benefit of "friends" marshal.c and _decimal.c. */

/* Parameters of the integer representation. There are two different

sets of parameters: one set for 30-bit digits, stored in an unsigned 32-bit

integer type, and one set for 15-bit digits with each digit stored in an

unsigned short. The value of PYLONG_BITS_IN_DIGIT, defined either at

configure time or in pyport.h, is used to decide which digit size to use.

Type 'digit' should be able to hold 2*PyLong_BASE-1, and type 'twodigits'

should be an unsigned integer type able to hold all integers up to

PyLong_BASE*PyLong_BASE-1. x_sub assumes that 'digit' is an unsigned type,

and that overflow is handled by taking the result modulo 2**N for some N >

PyLong_SHIFT. The majority of the code doesn't care about the precise

value of PyLong_SHIFT, but there are some notable exceptions:

- long_pow() requires that PyLong_SHIFT be divisible by 5

- PyLong_{As,From}ByteArray require that PyLong_SHIFT be at least 8

- long_hash() requires that PyLong_SHIFT is *strictly* less than the number

of bits in an unsigned long, as do the PyLong <-> long (or unsigned long)

conversion functions

- the Python int <-> size_t/Py_ssize_t conversion functions expect that

PyLong_SHIFT is strictly less than the number of bits in a size_t

- the marshal code currently expects that PyLong_SHIFT is a multiple of 15

- NSMALLNEGINTS and NSMALLPOSINTS should be small enough to fit in a single

digit; with the current values this forces PyLong_SHIFT >= 9

The values 15 and 30 should fit all of the above requirements, on any

platform.

#if PYLONG_BITS_IN_DIGIT == 30

#if !(defined HAVE_UINT64_T && defined HAVE_UINT32_T && \

defined HAVE_INT64_T && defined HAVE_INT32_T)

#error "30-bit long digits requested, but the necessary types are not available on this platform"

#endif

typedef PY_UINT32_T digit;

typedef PY_INT32_T sdigit; /* signed variant of digit */

typedef PY_UINT64_T twodigits;

typedef PY_INT64_T stwodigits; /* signed variant of twodigits */

#define PyLong_SHIFT 30

#define _PyLong_DECIMAL_SHIFT 9 /* max(e such that 10**e fits in a digit) */

#define _PyLong_DECIMAL_BASE ((digit)1000000000) /* 10 ** DECIMAL_SHIFT */

#elif PYLONG_BITS_IN_DIGIT == 15

typedef unsigned short digit;

typedef short sdigit; /* signed variant of digit */

typedef unsigned long twodigits;

typedef long stwodigits; /* signed variant of twodigits */

#define PyLong_SHIFT 15

#define _PyLong_DECIMAL_SHIFT 4 /* max(e such that 10**e fits in a digit) */

#define _PyLong_DECIMAL_BASE ((digit)10000) /* 10 ** DECIMAL_SHIFT */

#else

#error "PYLONG_BITS_IN_DIGIT should be 15 or 30"

#endif

#define PyLong_BASE ((digit)1 << PyLong_SHIFT)

#define PyLong_MASK ((digit)(PyLong_BASE - 1))

#if PyLong_SHIFT % 5 != 0

#error "longobject.c requires that PyLong_SHIFT be divisible by 5"

#endif

/* Long integer representation.

The absolute value of a number is equal to

SUM(for i=0 through abs(ob_size)-1) ob_digit[i] * 2**(SHIFT*i)

Negative numbers are represented with ob_size < 0;

zero is represented by ob_size == 0.

In a normalized number, ob_digit[abs(ob_size)-1] (the most significant

digit) is never zero. Also, in all cases, for all valid i,

0 <= ob_digit[i] <= MASK.

The allocation function takes care of allocating extra memory

so that ob_digit[0] ... ob_digit[abs(ob_size)-1] are actually available.

CAUTION: Generic code manipulating subtypes of PyVarObject has to

aware that ints abuse ob_size's sign bit.

struct _longobject {

PyObject_VAR_HEAD

digit ob_digit[1];

};

PyAPI_FUNC(PyLongObject *) _PyLong_New(Py_ssize_t);

/* Return a copy of src. */

PyAPI_FUNC(PyObject *) _PyLong_Copy(PyLongObject *src);

#ifdef __cplusplus

}

#endif

#endif /* !Py_LONGINTREPR_H */

#endif /* Py_LIMITED_API */

UnrealEnginePython/android/python35/include/longintrepr.h at develop · breezonto/UnrealEnginePython · GitHub

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