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Cray J90 fixes for long ints.

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This was a convenient excuse to create the pyport.h file recently
discussed!
Please use new Py_ARITHMETIC_RIGHT_SHIFT when right-shifting a
signed int and you *need* sign-extension.  This is #define'd in
pyport.h, keying off new config symbol SIGNED_RIGHT_SHIFT_ZERO_FILLS.
If you're running on a platform that needs that symbol #define'd,
the std tests never would have worked for you (in particular,
at least test_long would have failed).
The autoconfig stuff got added to Python after my Unix days, so
I don't know how that works.  Would someone please look into doing
& testing an auto-config of the SIGNED_RIGHT_SHIFT_ZERO_FILLS
symbol?  It needs to be defined if & only if, e.g., (-1) >> 3 is
not -1.
This commit is contained in:
Tim Peters 2000-07-08 04:17:21 +00:00
parent 5639ba4896
commit 7d3a511a40
6 changed files with 76 additions and 12 deletions
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13
Objects/longobject.c
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@ -571,7 +571,8 @@ long_format(PyObject *aa, int base, int addL)
int last = abs(a->ob_size);
int basebits = 1;
i = base;
while ((i >>= 1) > 1) ++basebits;
while ((i >>= 1) > 1)
++basebits;
i = 0;
for (;;) {
@ -853,7 +854,9 @@ x_divrem(PyLongObject *v1, PyLongObject *w1, PyLongObject **prem)
carry += v->ob_digit[i+k] - z
+ ((twodigits)zz << SHIFT);
v->ob_digit[i+k] = carry & MASK;
carry = (carry >> SHIFT) - zz;
carry = Py_ARITHMETIC_RIGHT_SHIFT(BASE_TWODIGITS_TYPE,
carry, SHIFT);
carry -= zz;
}
if (i+k < size_v) {
@ -870,7 +873,9 @@ x_divrem(PyLongObject *v1, PyLongObject *w1, PyLongObject **prem)
for (i = 0; i < size_w && i+k < size_v; ++i) {
carry += v->ob_digit[i+k] + w->ob_digit[i];
v->ob_digit[i+k] = carry & MASK;
carry >>= SHIFT;
carry = Py_ARITHMETIC_RIGHT_SHIFT(
BASE_TWODIGITS_TYPE,
carry, SHIFT);
}
}
} /* for j, k */
@ -988,8 +993,6 @@ x_add(PyLongObject *a, PyLongObject *b)
for (i = 0; i < size_b; ++i) {
carry += a->ob_digit[i] + b->ob_digit[i];
z->ob_digit[i] = carry & MASK;
/* The following assumes unsigned shifts don't
propagate the sign bit. */
carry >>= SHIFT;
}
for (; i < size_a; ++i) {