mirror of
https://github.com/python/cpython.git
synced 2024-11-24 17:47:13 +01:00
9f2e346911
svn+ssh://pythondev@svn.python.org/python/branches/p3yk
................
r56477 | martin.v.loewis | 2007-07-21 09:04:38 +0200 (Sa, 21 Jul 2007) | 11 lines
Merged revisions 56466-56476 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r56476 | martin.v.loewis | 2007-07-21 08:55:02 +0200 (Sa, 21 Jul 2007) | 4 lines
PEP 3123: Provide forward compatibility with Python 3.0, while keeping
backwards compatibility. Add Py_Refcnt, Py_Type, Py_Size, and
PyVarObject_HEAD_INIT.
........
................
r56478 | martin.v.loewis | 2007-07-21 09:47:23 +0200 (Sa, 21 Jul 2007) | 2 lines
PEP 3123: Use proper C inheritance for PyObject.
................
r56479 | martin.v.loewis | 2007-07-21 10:06:55 +0200 (Sa, 21 Jul 2007) | 3 lines
Add longintrepr.h to Python.h, so that the compiler can
see that PyFalse is really some kind of PyObject*.
................
r56480 | martin.v.loewis | 2007-07-21 10:47:18 +0200 (Sa, 21 Jul 2007) | 2 lines
Qualify SHIFT, MASK, BASE.
................
r56482 | martin.v.loewis | 2007-07-21 19:10:57 +0200 (Sa, 21 Jul 2007) | 2 lines
Correctly refer to _ob_next.
................
64 lines
2.1 KiB
C
64 lines
2.1 KiB
C
#ifndef Py_LONGINTREPR_H
|
|
#define Py_LONGINTREPR_H
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
|
|
/* This is published for the benefit of "friend" marshal.c only. */
|
|
|
|
/* Parameters of the long integer representation.
|
|
These shouldn't have to be changed as C should guarantee that a short
|
|
contains at least 16 bits, but it's made changeable anyway.
|
|
Note: 'digit' should be able to hold 2*MASK+1, and 'twodigits'
|
|
should be able to hold the intermediate results in 'mul'
|
|
(at most (BASE-1)*(2*BASE+1) == MASK*(2*MASK+3)).
|
|
Also, x_sub assumes that 'digit' is an unsigned type, and overflow
|
|
is handled by taking the result mod 2**N for some N > SHIFT.
|
|
And, at some places it is assumed that MASK fits in an int, as well.
|
|
long_pow() requires that SHIFT be divisible by 5. */
|
|
|
|
typedef unsigned short digit;
|
|
typedef unsigned int wdigit; /* digit widened to parameter size */
|
|
#define BASE_TWODIGITS_TYPE long
|
|
typedef unsigned BASE_TWODIGITS_TYPE twodigits;
|
|
typedef BASE_TWODIGITS_TYPE stwodigits; /* signed variant of twodigits */
|
|
|
|
#define PyLong_SHIFT 15
|
|
#define PyLong_BASE ((digit)1 << PyLong_SHIFT)
|
|
#define PyLong_MASK ((int)(PyLong_BASE - 1))
|
|
|
|
#if PyLong_SHIFT % 5 != 0
|
|
#error "longobject.c requires that 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 longs 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 */
|