circuitpython/tests/basics/int_big_div.py
Damien George dc3faea040 py/mpz: Fix bug with overflowing C-shift in division routine.
When DIG_SIZE=32, a uint32_t is used to store limbs, and no normalisation
is needed because the MSB is already set, then there will be left and
right shifts (in C) by 32 of a 32-bit variable, leading to undefined
behaviour.  This patch fixes this bug.
2016-05-08 21:38:43 +01:00

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Python

for lhs in (1000000000000000000000000, 10000000000100000000000000, 10012003400000000000000007, 12349083434598210349871029923874109871234789):
for rhs in range(1, 555):
print(lhs // rhs)
# these check an edge case on 64-bit machines where two mpz limbs
# are used and the most significant one has the MSB set
x = 0x8000000000000000
print((x + 1) // x)
x = 0x86c60128feff5330
print((x + 1) // x)