[ovs-dev] [PATCH v2 2/9] lib/util: Add ctz64() and popcount64().

[Jarno Rajahalme]

Pushed to master,

  Jarno

On Nov 15, 2013, at 4:15 PM, Jarno Rajahalme <jrajahalme at nicira.com> wrote:

> 
>> On Nov 15, 2013, at 4:08 PM, Ben Pfaff <blp at nicira.com> wrote:
>> 
>>> On Fri, Nov 15, 2013 at 04:03:32PM -0800, Jarno Rajahalme wrote:
>>> 
>>>>> On Nov 15, 2013, at 3:48 PM, Ben Pfaff <blp at nicira.com> wrote:
>>>>> 
>>>>> On Wed, Nov 13, 2013 at 01:32:42PM -0800, Jarno Rajahalme wrote:
>>>>> Add raw_ctz64(), ctz64(), and popcount64() using builtins when
>>>>> available.
>>>>> 
>>>>> I'm not sure if the "UINT64_MAX == ~0UL" and "UINT64_MAX == ~0ULL"
>>>>> work in all cases as I imagine they would.
>>>> 
>>>> I think you could use ULONG_MAX and ULLONG_MAX, any reason not to?
>>> 
>>> It doesn't matter if they are the same in some cases, right?
>> 
>> Actually, I guess we can just skip the test entirely.  GCC always
>> supports 64-bit integers as unsigned long long, so this by itself
>> ought to do the trick:
>> 
>>   #elif __GNUC__ >= 4
>>   static inline int
>>   raw_ctz64(uint64_t n)
>>   {
>>       return __builtin_ctzll(n);
>>   }
>>   static inline int
>>   popcount64(uint64_t n)
>>   {
>>       return __builtin_popcountll(n);
>>   }
> 
> Thanks Ben, I'll fold this in.
> 
>  Jarno
>