On 12/14/2017 11:47 AM, Wei Wang wrote:
On 12/13/2017 10:16 PM, Tetsuo Handa wrote:
if (set)
ret = find_next_bit(&tmp,
BITS_PER_LONG, ebit);
else
ret = find_next_zero_bit(&tmp,
BITS_PER_LONG,
ebit);
if (ret < BITS_PER_LONG)
return ret - 2 + ida_start;
} else if (bitmap) {
if (set)
ret = find_next_bit(bitmap->bitmap,
IDA_BITMAP_BITS, bit);
else
ret =
find_next_zero_bit(bitmap->bitmap,
IDA_BITMAP_BITS, bit);
"bit" may not be 0 for the first round and "bit" is always 0 afterwords.
But where is the guaranteed that "end" is a multiple of
IDA_BITMAP_BITS ?
Please explain why it is correct to use IDA_BITMAP_BITS unconditionally
for the last round.
There missed something here, it will be:
nbits = min(end - ida_start + 1, IDA_BITMAP_BITS - bit);
captured a bug here, should be:
nbits = min(end - ida_start + 1, (unsigned long)IDA_BITMAP_BITS);
if (set)
ret = find_next_bit(bitmap->bitmap, nbits, bit);
else
ret = find_next_zero_bit(bitmap->bitmap,
nbits, bit);
if (ret < nbits)
return ret + ida_start;
Best,
Wei
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