On 05/14/2017 08:15 AM, clipka wrote:
> Am 14.05.2017 um 13:17 schrieb William F Pokorny:
>> On 05/14/2017 06:08 AM, clipka wrote:
>>> Am 08.05.2017 um 02:13 schrieb green:
>>>
>>> MS Visual Studio has an option called "Whole Program Optimization",
>>> which allows the compiler/linker to optimize stuff looking at the "big
>>> picture" rather than just individual source files. Apparently this can
>>> cause a mess when programs have source files compiled with AVX
>>> instructions enabled and others without, in that the compiler/linker may
>>> accidentally "contaminate" the AVX-free portions with calls to portions
>>> which happen to have been compiled with AVX instructions enabled.
>>>
>>>
>> Have you done any performance comparisons with and without this
>> optimization?
>
> Not before; but running a quick test just now, disabling whole program
> optimization seems to give me a 6% performance drop on my machine, so
> that settles it for me.
>
>
Wow, six percent! Thanks for doing the test. Significant enough to look 
again at this sort of optimization with the gnu compiler / linker.

Bill P.

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