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Instead of be limited just by the size of addressable memory (2**63 bytes), Python integers are now also limited by the number of bits, so the number of bit now always fit in a 64-bit integer. Both limits are much larger than what might be available in practice, so it doesn't affect users. _PyLong_NumBits() and _PyLong_Frexp() are now always successful.
This commit is contained in:
parent
e0a41a5dd1
commit
d08c788822
@ -71,10 +71,9 @@ PyAPI_FUNC(int) _PyLong_Sign(PyObject *v);
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absolute value of a long. For example, this returns 1 for 1 and -1, 2
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for 2 and -2, and 2 for 3 and -3. It returns 0 for 0.
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v must not be NULL, and must be a normalized long.
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(uint64_t)-1 is returned and OverflowError set if the true result doesn't
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fit in a size_t.
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Always successful.
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*/
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PyAPI_FUNC(uint64_t) _PyLong_NumBits(PyObject *v);
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PyAPI_FUNC(int64_t) _PyLong_NumBits(PyObject *v);
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/* _PyLong_FromByteArray: View the n unsigned bytes as a binary integer in
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base 256, and return a Python int with the same numeric value.
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@ -79,11 +79,10 @@ static inline PyObject* _PyLong_FromUnsignedChar(unsigned char i)
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}
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// _PyLong_Frexp returns a double x and an exponent e such that the
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// true value is approximately equal to x * 2**e. e is >= 0. x is
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// true value is approximately equal to x * 2**e. x is
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// 0.0 if and only if the input is 0 (in which case, e and x are both
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// zeroes); otherwise, 0.5 <= abs(x) < 1.0. On overflow, which is
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// possible if the number of bits doesn't fit into a Py_ssize_t, sets
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// OverflowError and returns -1.0 for x, 0 for e.
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// zeroes); otherwise, 0.5 <= abs(x) < 1.0.
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// Always successful.
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//
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// Export for 'math' shared extension
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PyAPI_DATA(double) _PyLong_Frexp(PyLongObject *a, int64_t *e);
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@ -105,10 +104,10 @@ PyAPI_DATA(PyObject*) _PyLong_DivmodNear(PyObject *, PyObject *);
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PyAPI_DATA(PyObject*) _PyLong_Format(PyObject *obj, int base);
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// Export for 'math' shared extension
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PyAPI_DATA(PyObject*) _PyLong_Rshift(PyObject *, uint64_t);
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PyAPI_DATA(PyObject*) _PyLong_Rshift(PyObject *, int64_t);
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// Export for 'math' shared extension
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PyAPI_DATA(PyObject*) _PyLong_Lshift(PyObject *, uint64_t);
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PyAPI_DATA(PyObject*) _PyLong_Lshift(PyObject *, int64_t);
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PyAPI_FUNC(PyObject*) _PyLong_Add(PyLongObject *left, PyLongObject *right);
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PyAPI_FUNC(PyObject*) _PyLong_Multiply(PyLongObject *left, PyLongObject *right);
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@ -2146,7 +2146,7 @@ save_long(PicklerObject *self, PyObject *obj)
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if (self->proto >= 2) {
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/* Linear-time pickling. */
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uint64_t nbits;
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int64_t nbits;
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size_t nbytes;
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unsigned char *pdata;
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char header[5];
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@ -2161,8 +2161,8 @@ save_long(PicklerObject *self, PyObject *obj)
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return 0;
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}
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nbits = _PyLong_NumBits(obj);
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if (nbits == (uint64_t)-1 && PyErr_Occurred())
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goto error;
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assert(nbits >= 0);
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assert(!PyErr_Occurred());
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/* How many bytes do we need? There are nbits >> 3 full
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* bytes of data, and nbits & 7 leftover bits. If there
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* are any leftover bits, then we clearly need another
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@ -295,7 +295,7 @@ random_seed(RandomObject *self, PyObject *arg)
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int result = -1; /* guilty until proved innocent */
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PyObject *n = NULL;
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uint32_t *key = NULL;
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uint64_t bits;
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int64_t bits;
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size_t keyused;
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int res;
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@ -335,8 +335,8 @@ random_seed(RandomObject *self, PyObject *arg)
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/* Now split n into 32-bit chunks, from the right. */
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bits = _PyLong_NumBits(n);
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if (bits == (uint64_t)-1 && PyErr_Occurred())
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goto Done;
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assert(bits >= 0);
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assert(!PyErr_Occurred());
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/* Figure out how many 32-bit chunks this gives us. */
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keyused = bits == 0 ? 1 : (size_t)((bits - 1) / 32 + 1);
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@ -1657,7 +1657,7 @@ math_isqrt(PyObject *module, PyObject *n)
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/*[clinic end generated code: output=35a6f7f980beab26 input=5b6e7ae4fa6c43d6]*/
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{
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int a_too_large, c_bit_length;
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uint64_t c, d;
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int64_t c, d;
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uint64_t m;
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uint32_t u;
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PyObject *a = NULL, *b;
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@ -1680,14 +1680,13 @@ math_isqrt(PyObject *module, PyObject *n)
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/* c = (n.bit_length() - 1) // 2 */
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c = _PyLong_NumBits(n);
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if (c == (uint64_t)(-1)) {
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goto error;
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}
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c = (c - 1U) / 2U;
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assert(c > 0);
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assert(!PyErr_Occurred());
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c = (c - 1) / 2;
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/* Fast path: if c <= 31 then n < 2**64 and we can compute directly with a
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fast, almost branch-free algorithm. */
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if (c <= 31U) {
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if (c <= 31) {
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int shift = 31 - (int)c;
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m = (uint64_t)PyLong_AsUnsignedLongLong(n);
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Py_DECREF(n);
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@ -1704,13 +1703,13 @@ math_isqrt(PyObject *module, PyObject *n)
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/* From n >= 2**64 it follows that c.bit_length() >= 6. */
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c_bit_length = 6;
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while ((c >> c_bit_length) > 0U) {
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while ((c >> c_bit_length) > 0) {
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++c_bit_length;
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}
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/* Initialise d and a. */
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d = c >> (c_bit_length - 5);
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b = _PyLong_Rshift(n, 2U*c - 62U);
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b = _PyLong_Rshift(n, 2*c - 62);
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if (b == NULL) {
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goto error;
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}
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@ -1727,12 +1726,12 @@ math_isqrt(PyObject *module, PyObject *n)
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for (int s = c_bit_length - 6; s >= 0; --s) {
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PyObject *q;
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uint64_t e = d;
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int64_t e = d;
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d = c >> s;
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/* q = (n >> 2*c - e - d + 1) // a */
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q = _PyLong_Rshift(n, 2U*c - d - e + 1U);
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q = _PyLong_Rshift(n, 2*c - d - e + 1);
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if (q == NULL) {
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goto error;
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}
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@ -1742,7 +1741,7 @@ math_isqrt(PyObject *module, PyObject *n)
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}
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/* a = (a << d - 1 - e) + q */
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Py_SETREF(a, _PyLong_Lshift(a, d - 1U - e));
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Py_SETREF(a, _PyLong_Lshift(a, d - 1 - e));
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if (a == NULL) {
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Py_DECREF(q);
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goto error;
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@ -2202,8 +2201,8 @@ loghelper(PyObject* arg, double (*func)(double))
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to compute the log anyway. Clear the exception and continue. */
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PyErr_Clear();
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x = _PyLong_Frexp((PyLongObject *)arg, &e);
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if (x == -1.0 && PyErr_Occurred())
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return NULL;
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assert(e >= 0);
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assert(!PyErr_Occurred());
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/* Value is ~= x * 2**e, so the log ~= log(x) + log(2) * e. */
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result = func(x) + func(2.0) * e;
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}
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@ -406,19 +406,16 @@ float_richcompare(PyObject *v, PyObject *w, int op)
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}
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/* The signs are the same. */
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/* Convert w to a double if it fits. In particular, 0 fits. */
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uint64_t nbits64 = _PyLong_NumBits(w);
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if (nbits64 > (unsigned int)DBL_MAX_EXP) {
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int64_t nbits64 = _PyLong_NumBits(w);
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assert(nbits64 >= 0);
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assert(!PyErr_Occurred());
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if (nbits64 > DBL_MAX_EXP) {
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/* This Python integer is larger than any finite C double.
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* Replace with little doubles
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* that give the same outcome -- w is so large that
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* its magnitude must exceed the magnitude of any
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* finite float.
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*/
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if (nbits64 == (uint64_t)-1 && PyErr_Occurred()) {
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/* This Python integer is so large that uint64_t isn't
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* big enough to hold the # of bits. */
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PyErr_Clear();
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}
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i = (double)vsign;
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assert(wsign != 0);
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j = wsign * 2.0;
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@ -133,8 +133,16 @@ long_normalize(PyLongObject *v)
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/* Allocate a new int object with size digits.
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Return NULL and set exception if we run out of memory. */
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#define MAX_LONG_DIGITS \
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#if SIZEOF_SIZE_T < 8
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# define MAX_LONG_DIGITS \
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((PY_SSIZE_T_MAX - offsetof(PyLongObject, long_value.ob_digit))/sizeof(digit))
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#else
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/* Guarantee that the number of bits fits in int64_t.
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This is more than an exbibyte, that is more than many of modern
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architectures support in principle.
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-1 is added to avoid overflow in _PyLong_Frexp(). */
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# define MAX_LONG_DIGITS ((INT64_MAX-1) / PyLong_SHIFT)
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#endif
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PyLongObject *
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_PyLong_New(Py_ssize_t size)
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@ -804,11 +812,11 @@ bit_length_digit(digit x)
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return _Py_bit_length((unsigned long)x);
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}
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uint64_t
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int64_t
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_PyLong_NumBits(PyObject *vv)
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{
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PyLongObject *v = (PyLongObject *)vv;
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uint64_t result = 0;
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int64_t result = 0;
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Py_ssize_t ndigits;
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int msd_bits;
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@ -818,21 +826,12 @@ _PyLong_NumBits(PyObject *vv)
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assert(ndigits == 0 || v->long_value.ob_digit[ndigits - 1] != 0);
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if (ndigits > 0) {
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digit msd = v->long_value.ob_digit[ndigits - 1];
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if ((uint64_t)(ndigits - 1) > UINT64_MAX / (uint64_t)PyLong_SHIFT)
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goto Overflow;
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result = (uint64_t)(ndigits - 1) * (uint64_t)PyLong_SHIFT;
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assert(ndigits <= INT64_MAX / PyLong_SHIFT);
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result = (int64_t)(ndigits - 1) * PyLong_SHIFT;
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msd_bits = bit_length_digit(msd);
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if (UINT64_MAX - msd_bits < result)
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goto Overflow;
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result += msd_bits;
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}
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return result;
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Overflow:
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/* Very unlikely. Such integer would require more than 2 exbibytes of RAM. */
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PyErr_SetString(PyExc_OverflowError, "int has too many bits "
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"to express in a 64-bit integer");
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return (uint64_t)-1;
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}
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PyObject *
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@ -1247,15 +1246,12 @@ PyLong_AsNativeBytes(PyObject* vv, void* buffer, Py_ssize_t n, int flags)
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/* Calculates the number of bits required for the *absolute* value
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* of v. This does not take sign into account, only magnitude. */
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uint64_t nb = _PyLong_NumBits((PyObject *)v);
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if (nb == (uint64_t)-1) {
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res = -1;
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} else {
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/* Normally this would be((nb - 1) / 8) + 1 to avoid rounding up
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* multiples of 8 to the next byte, but we add an implied bit for
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* the sign and it cancels out. */
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res = (Py_ssize_t)(nb / 8) + 1;
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}
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int64_t nb = _PyLong_NumBits((PyObject *)v);
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assert(nb >= 0);
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/* Normally this would be ((nb - 1) / 8) + 1 to avoid rounding up
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* multiples of 8 to the next byte, but we add an implied bit for
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* the sign and it cancels out. */
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res = (Py_ssize_t)(nb / 8) + 1;
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/* Two edge cases exist that are best handled after extracting the
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* bits. These may result in us reporting overflow when the value
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@ -3415,7 +3411,8 @@ x_divrem(PyLongObject *v1, PyLongObject *w1, PyLongObject **prem)
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double
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_PyLong_Frexp(PyLongObject *a, int64_t *e)
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{
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Py_ssize_t a_size, shift_digits, shift_bits, x_size;
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Py_ssize_t a_size, shift_digits, x_size;
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int shift_bits;
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int64_t a_bits;
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/* See below for why x_digits is always large enough. */
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digit rem;
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@ -3432,14 +3429,7 @@ _PyLong_Frexp(PyLongObject *a, int64_t *e)
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*e = 0;
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return 0.0;
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}
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int msd_bits = bit_length_digit(a->long_value.ob_digit[a_size-1]);
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/* The following is an overflow-free version of the check
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"if ((a_size - 1) * PyLong_SHIFT + msd_bits > PY_SSIZE_T_MAX) ..." */
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if (a_size >= (INT64_MAX - 1) / PyLong_SHIFT + 1 &&
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(a_size > (INT64_MAX - 1) / PyLong_SHIFT + 1 ||
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msd_bits > (INT64_MAX - 1) % PyLong_SHIFT + 1))
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goto overflow;
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a_bits = (int64_t)(a_size - 1) * PyLong_SHIFT + msd_bits;
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a_bits = _PyLong_NumBits((PyObject *)a);
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/* Shift the first DBL_MANT_DIG + 2 bits of a into x_digits[0:x_size]
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(shifting left if a_bits <= DBL_MANT_DIG + 2).
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@ -3468,18 +3458,18 @@ _PyLong_Frexp(PyLongObject *a, int64_t *e)
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*/
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if (a_bits <= DBL_MANT_DIG + 2) {
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shift_digits = (DBL_MANT_DIG + 2 - (Py_ssize_t)a_bits) / PyLong_SHIFT;
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shift_bits = (DBL_MANT_DIG + 2 - (Py_ssize_t)a_bits) % PyLong_SHIFT;
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shift_bits = (DBL_MANT_DIG + 2 - (int)a_bits) % PyLong_SHIFT;
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x_size = shift_digits;
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rem = v_lshift(x_digits + x_size, a->long_value.ob_digit, a_size,
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(int)shift_bits);
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shift_bits);
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x_size += a_size;
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x_digits[x_size++] = rem;
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}
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else {
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shift_digits = (Py_ssize_t)((a_bits - DBL_MANT_DIG - 2) / PyLong_SHIFT);
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shift_bits = (Py_ssize_t)((a_bits - DBL_MANT_DIG - 2) % PyLong_SHIFT);
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shift_bits = (int)((a_bits - DBL_MANT_DIG - 2) % PyLong_SHIFT);
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rem = v_rshift(x_digits, a->long_value.ob_digit + shift_digits,
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a_size - shift_digits, (int)shift_bits);
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a_size - shift_digits, shift_bits);
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x_size = a_size - shift_digits;
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/* For correct rounding below, we need the least significant
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bit of x to be 'sticky' for this shift: if any of the bits
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@ -3505,21 +3495,13 @@ _PyLong_Frexp(PyLongObject *a, int64_t *e)
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/* Rescale; make correction if result is 1.0. */
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dx /= 4.0 * EXP2_DBL_MANT_DIG;
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if (dx == 1.0) {
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if (a_bits == INT64_MAX)
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goto overflow;
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assert(a_bits < INT64_MAX);
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dx = 0.5;
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a_bits += 1;
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}
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*e = a_bits;
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return _PyLong_IsNegative(a) ? -dx : dx;
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overflow:
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/* exponent > PY_SSIZE_T_MAX */
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PyErr_SetString(PyExc_OverflowError,
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"huge integer: number of bits overflows a Py_ssize_t");
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*e = 0;
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return -1.0;
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}
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/* Get a C double from an int object. Rounds to the nearest double,
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@ -3547,7 +3529,9 @@ PyLong_AsDouble(PyObject *v)
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return (double)medium_value((PyLongObject *)v);
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}
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x = _PyLong_Frexp((PyLongObject *)v, &exponent);
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if ((x == -1.0 && PyErr_Occurred()) || exponent > DBL_MAX_EXP) {
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assert(exponent >= 0);
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assert(!PyErr_Occurred());
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if (exponent > DBL_MAX_EXP) {
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PyErr_SetString(PyExc_OverflowError,
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"int too large to convert to float");
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return -1.0;
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@ -5217,39 +5201,6 @@ long_bool(PyLongObject *v)
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return !_PyLong_IsZero(v);
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}
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/* wordshift, remshift = divmod(shiftby, PyLong_SHIFT) */
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static int
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divmod_shift(PyObject *shiftby, Py_ssize_t *wordshift, digit *remshift)
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{
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assert(PyLong_Check(shiftby));
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assert(!_PyLong_IsNegative((PyLongObject *)shiftby));
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Py_ssize_t lshiftby = PyLong_AsSsize_t((PyObject *)shiftby);
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if (lshiftby >= 0) {
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*wordshift = lshiftby / PyLong_SHIFT;
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*remshift = lshiftby % PyLong_SHIFT;
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return 0;
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}
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/* PyLong_Check(shiftby) is true and shiftby is not negative, so it must
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be that PyLong_AsSsize_t raised an OverflowError. */
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assert(PyErr_ExceptionMatches(PyExc_OverflowError));
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PyErr_Clear();
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PyLongObject *wordshift_obj = divrem1((PyLongObject *)shiftby, PyLong_SHIFT, remshift);
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if (wordshift_obj == NULL) {
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return -1;
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}
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*wordshift = PyLong_AsSsize_t((PyObject *)wordshift_obj);
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Py_DECREF(wordshift_obj);
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if (*wordshift >= 0 && *wordshift < PY_SSIZE_T_MAX / (Py_ssize_t)sizeof(digit)) {
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return 0;
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}
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PyErr_Clear();
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/* Clip the value. With such large wordshift the right shift
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returns 0 and the left shift raises an error in _PyLong_New(). */
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*wordshift = PY_SSIZE_T_MAX / sizeof(digit);
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*remshift = 0;
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return 0;
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}
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/* Inner function for both long_rshift and _PyLong_Rshift, shifting an
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integer right by PyLong_SHIFT*wordshift + remshift bits.
|
||||
wordshift should be nonnegative. */
|
||||
@ -5343,8 +5294,7 @@ long_rshift1(PyLongObject *a, Py_ssize_t wordshift, digit remshift)
|
||||
static PyObject *
|
||||
long_rshift(PyObject *a, PyObject *b)
|
||||
{
|
||||
Py_ssize_t wordshift;
|
||||
digit remshift;
|
||||
int64_t shiftby;
|
||||
|
||||
CHECK_BINOP(a, b);
|
||||
|
||||
@ -5355,24 +5305,35 @@ long_rshift(PyObject *a, PyObject *b)
|
||||
if (_PyLong_IsZero((PyLongObject *)a)) {
|
||||
return PyLong_FromLong(0);
|
||||
}
|
||||
if (divmod_shift(b, &wordshift, &remshift) < 0)
|
||||
return NULL;
|
||||
return long_rshift1((PyLongObject *)a, wordshift, remshift);
|
||||
if (PyLong_AsInt64(b, &shiftby) < 0) {
|
||||
if (!PyErr_ExceptionMatches(PyExc_OverflowError)) {
|
||||
return NULL;
|
||||
}
|
||||
PyErr_Clear();
|
||||
if (_PyLong_IsNegative((PyLongObject *)a)) {
|
||||
return PyLong_FromLong(-1);
|
||||
}
|
||||
else {
|
||||
return PyLong_FromLong(0);
|
||||
}
|
||||
}
|
||||
return _PyLong_Rshift(a, shiftby);
|
||||
}
|
||||
|
||||
/* Return a >> shiftby. */
|
||||
PyObject *
|
||||
_PyLong_Rshift(PyObject *a, uint64_t shiftby)
|
||||
_PyLong_Rshift(PyObject *a, int64_t shiftby)
|
||||
{
|
||||
Py_ssize_t wordshift;
|
||||
digit remshift;
|
||||
|
||||
assert(PyLong_Check(a));
|
||||
assert(shiftby >= 0);
|
||||
if (_PyLong_IsZero((PyLongObject *)a)) {
|
||||
return PyLong_FromLong(0);
|
||||
}
|
||||
#if PY_SSIZE_T_MAX <= UINT64_MAX / PyLong_SHIFT
|
||||
if (shiftby > (uint64_t)PY_SSIZE_T_MAX * PyLong_SHIFT) {
|
||||
#if PY_SSIZE_T_MAX <= INT64_MAX / PyLong_SHIFT
|
||||
if (shiftby > (int64_t)PY_SSIZE_T_MAX * PyLong_SHIFT) {
|
||||
if (_PyLong_IsNegative((PyLongObject *)a)) {
|
||||
return PyLong_FromLong(-1);
|
||||
}
|
||||
@ -5430,8 +5391,7 @@ long_lshift1(PyLongObject *a, Py_ssize_t wordshift, digit remshift)
|
||||
static PyObject *
|
||||
long_lshift(PyObject *a, PyObject *b)
|
||||
{
|
||||
Py_ssize_t wordshift;
|
||||
digit remshift;
|
||||
int64_t shiftby;
|
||||
|
||||
CHECK_BINOP(a, b);
|
||||
|
||||
@ -5442,24 +5402,30 @@ long_lshift(PyObject *a, PyObject *b)
|
||||
if (_PyLong_IsZero((PyLongObject *)a)) {
|
||||
return PyLong_FromLong(0);
|
||||
}
|
||||
if (divmod_shift(b, &wordshift, &remshift) < 0)
|
||||
if (PyLong_AsInt64(b, &shiftby) < 0) {
|
||||
if (PyErr_ExceptionMatches(PyExc_OverflowError)) {
|
||||
PyErr_SetString(PyExc_OverflowError,
|
||||
"too many digits in integer");
|
||||
}
|
||||
return NULL;
|
||||
return long_lshift1((PyLongObject *)a, wordshift, remshift);
|
||||
}
|
||||
return _PyLong_Lshift(a, shiftby);
|
||||
}
|
||||
|
||||
/* Return a << shiftby. */
|
||||
PyObject *
|
||||
_PyLong_Lshift(PyObject *a, uint64_t shiftby)
|
||||
_PyLong_Lshift(PyObject *a, int64_t shiftby)
|
||||
{
|
||||
Py_ssize_t wordshift;
|
||||
digit remshift;
|
||||
|
||||
assert(PyLong_Check(a));
|
||||
assert(shiftby >= 0);
|
||||
if (_PyLong_IsZero((PyLongObject *)a)) {
|
||||
return PyLong_FromLong(0);
|
||||
}
|
||||
#if PY_SSIZE_T_MAX <= UINT64_MAX / PyLong_SHIFT
|
||||
if (shiftby > (uint64_t)PY_SSIZE_T_MAX * PyLong_SHIFT) {
|
||||
#if PY_SSIZE_T_MAX <= INT64_MAX / PyLong_SHIFT
|
||||
if (shiftby > (int64_t)PY_SSIZE_T_MAX * PyLong_SHIFT) {
|
||||
PyErr_SetString(PyExc_OverflowError,
|
||||
"too many digits in integer");
|
||||
return NULL;
|
||||
@ -6213,11 +6179,10 @@ static PyObject *
|
||||
int_bit_length_impl(PyObject *self)
|
||||
/*[clinic end generated code: output=fc1977c9353d6a59 input=e4eb7a587e849a32]*/
|
||||
{
|
||||
uint64_t nbits = _PyLong_NumBits(self);
|
||||
if (nbits == (uint64_t)-1) {
|
||||
return NULL;
|
||||
}
|
||||
return PyLong_FromUnsignedLongLong(nbits);
|
||||
int64_t nbits = _PyLong_NumBits(self);
|
||||
assert(nbits >= 0);
|
||||
assert(!PyErr_Occurred());
|
||||
return PyLong_FromInt64(nbits);
|
||||
}
|
||||
|
||||
static int
|
||||
@ -6251,40 +6216,13 @@ int_bit_count_impl(PyObject *self)
|
||||
|
||||
PyLongObject *z = (PyLongObject *)self;
|
||||
Py_ssize_t ndigits = _PyLong_DigitCount(z);
|
||||
Py_ssize_t bit_count = 0;
|
||||
int64_t bit_count = 0;
|
||||
|
||||
/* Each digit has up to PyLong_SHIFT ones, so the accumulated bit count
|
||||
from the first PY_SSIZE_T_MAX/PyLong_SHIFT digits can't overflow a
|
||||
Py_ssize_t. */
|
||||
Py_ssize_t ndigits_fast = Py_MIN(ndigits, PY_SSIZE_T_MAX/PyLong_SHIFT);
|
||||
for (Py_ssize_t i = 0; i < ndigits_fast; i++) {
|
||||
for (Py_ssize_t i = 0; i < ndigits; i++) {
|
||||
bit_count += popcount_digit(z->long_value.ob_digit[i]);
|
||||
}
|
||||
|
||||
PyObject *result = PyLong_FromSsize_t(bit_count);
|
||||
if (result == NULL) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Use Python integers if bit_count would overflow. */
|
||||
for (Py_ssize_t i = ndigits_fast; i < ndigits; i++) {
|
||||
PyObject *x = PyLong_FromLong(popcount_digit(z->long_value.ob_digit[i]));
|
||||
if (x == NULL) {
|
||||
goto error;
|
||||
}
|
||||
PyObject *y = long_add((PyLongObject *)result, (PyLongObject *)x);
|
||||
Py_DECREF(x);
|
||||
if (y == NULL) {
|
||||
goto error;
|
||||
}
|
||||
Py_SETREF(result, y);
|
||||
}
|
||||
|
||||
return result;
|
||||
|
||||
error:
|
||||
Py_DECREF(result);
|
||||
return NULL;
|
||||
return PyLong_FromInt64(bit_count);
|
||||
}
|
||||
|
||||
/*[clinic input]
|
||||
|
@ -169,11 +169,10 @@ safe_multiply(PyObject *v, PyObject *w)
|
||||
if (PyLong_Check(v) && PyLong_Check(w) &&
|
||||
!_PyLong_IsZero((PyLongObject *)v) && !_PyLong_IsZero((PyLongObject *)w)
|
||||
) {
|
||||
uint64_t vbits = _PyLong_NumBits(v);
|
||||
uint64_t wbits = _PyLong_NumBits(w);
|
||||
if (vbits == (uint64_t)-1 || wbits == (uint64_t)-1) {
|
||||
return NULL;
|
||||
}
|
||||
int64_t vbits = _PyLong_NumBits(v);
|
||||
int64_t wbits = _PyLong_NumBits(w);
|
||||
assert(vbits >= 0);
|
||||
assert(wbits >= 0);
|
||||
if (vbits + wbits > MAX_INT_SIZE) {
|
||||
return NULL;
|
||||
}
|
||||
@ -215,12 +214,13 @@ safe_power(PyObject *v, PyObject *w)
|
||||
if (PyLong_Check(v) && PyLong_Check(w) &&
|
||||
!_PyLong_IsZero((PyLongObject *)v) && _PyLong_IsPositive((PyLongObject *)w)
|
||||
) {
|
||||
uint64_t vbits = _PyLong_NumBits(v);
|
||||
int64_t vbits = _PyLong_NumBits(v);
|
||||
size_t wbits = PyLong_AsSize_t(w);
|
||||
if (vbits == (uint64_t)-1 || wbits == (size_t)-1) {
|
||||
assert(vbits >= 0);
|
||||
if (wbits == (size_t)-1) {
|
||||
return NULL;
|
||||
}
|
||||
if (vbits > MAX_INT_SIZE / wbits) {
|
||||
if ((uint64_t)vbits > MAX_INT_SIZE / wbits) {
|
||||
return NULL;
|
||||
}
|
||||
}
|
||||
@ -234,12 +234,13 @@ safe_lshift(PyObject *v, PyObject *w)
|
||||
if (PyLong_Check(v) && PyLong_Check(w) &&
|
||||
!_PyLong_IsZero((PyLongObject *)v) && !_PyLong_IsZero((PyLongObject *)w)
|
||||
) {
|
||||
uint64_t vbits = _PyLong_NumBits(v);
|
||||
int64_t vbits = _PyLong_NumBits(v);
|
||||
size_t wbits = PyLong_AsSize_t(w);
|
||||
if (vbits == (uint64_t)-1 || wbits == (size_t)-1) {
|
||||
assert(vbits >= 0);
|
||||
if (wbits == (size_t)-1) {
|
||||
return NULL;
|
||||
}
|
||||
if (wbits > MAX_INT_SIZE || vbits > MAX_INT_SIZE - wbits) {
|
||||
if (wbits > MAX_INT_SIZE || (uint64_t)vbits > MAX_INT_SIZE - wbits) {
|
||||
return NULL;
|
||||
}
|
||||
}
|
||||
|
Loading…
Reference in New Issue
Block a user