Cray J90 fixes for long ints.
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.
diff --git a/Objects/longobject.c b/Objects/longobject.c
index a28dbaf..df3c6a5 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -571,7 +571,8 @@
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 @@
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 @@
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 @@
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) {