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cpython/Include/longintrepr.h
Guido van Rossum 9bfef44d97 * Changed all copyright messages to include 1993.
* Stubs for faster implementation of local variables (not yet finished)
* Added function name to code object.  Print it for code and function
  objects.  THIS MAKES THE .PYC FILE FORMAT INCOMPATIBLE (the version
  number has changed accordingly)
* Print address of self for built-in methods
* New internal functions getattro and setattro (getattr/setattr with
  string object arg)
* Replaced "dictobject" with more powerful "mappingobject"
* New per-type functio tp_hash to implement arbitrary object hashing,
  and hashobject() to interface to it
* Added built-in functions hash(v) and hasattr(v, 'name')
* classobject: made some functions static that accidentally weren't;
  added __hash__ special instance method to implement hash()
* Added proper comparison for built-in methods and functions
1993-03-29 10:43:31 +00:00

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2.8 KiB
C

/***********************************************************
Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
Amsterdam, The Netherlands.
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior permission.
STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
******************************************************************/
/* 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 any way.
Note: 'digit' should be able to hold 2*MASK+1, and 'twodigits'
should be able to hold the intermediate results in 'mul'
(at most MASK << SHIFT).
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. */
typedef unsigned short digit;
typedef unsigned int wdigit; /* digit widened to parameter size */
typedef unsigned long twodigits;
typedef long stwodigits; /* signed variant of twodigits */
#define SHIFT 15
#define BASE ((digit)1 << SHIFT)
#define MASK ((int)(BASE - 1))
/* 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 fuction takes care of allocating extra memory
so that ob_digit[0] ... ob_digit[abs(ob_size)-1] are actually available. */
struct _longobject {
OB_HEAD
int ob_size; /* XXX Hack! newvarobj() stores it as unsigned! */
digit ob_digit[1];
};
longobject *alloclongobject PROTO((int));