From d08c7888229e78533648191dfe42e2d2d3ecea25 Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Sun, 29 Sep 2024 10:40:20 +0300 Subject: gh-123497: New limit for Python integers on 64-bit platforms (GH-123724) 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. --- Python/ast_opt.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) (limited to 'Python/ast_opt.c') diff --git a/Python/ast_opt.c b/Python/ast_opt.c index f5b04757e08..01e208b88ec 100644 --- a/Python/ast_opt.c +++ b/Python/ast_opt.c @@ -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; } } -- cgit v1.2.3