Re: [boost] [uuids] On boost::uuids::uuid operator == performance.

Subject: Re: [boost] [uuids] On boost::uuids::uuid operator == performance.
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2012-04-16 14:17:10

On 16/04/12 19:44, Michael Kochetkov wrote:
>>> I do remember that at least memcpy intrinsic worked pretty smart in
>>> that compiler.
>>
>> It does.
>>
>> I think I see what's going on. memcmp has to return -1, 0 or 1. This is
> why it
>> does an initial DWORD loop to find the first mismatch, then does a byte
>> compare to determine the return value.
> Thank you for pointing it out.  Frankly speaking being busy with finding out
> the attitude of the boost people towards  the problem I have really skipped
> the rest of generated code that have probably made the MS compiler to look a
> little bit smarter than it really is.

Boost being used on many operating systems, compilers, and 
architectures, generic solutions are usually preferred over ad-hoc fixes 
for particular compiler combinations.

That being said, a MSVC-specific workaround is possible too, if no other 
satisfying solution is found.