Explanation of vectorization Report

Explanation of vectorization Report

Does anybody understand what does the following means in a vectorization report:
src/main.cpp:19: note: vectorized 0 loops in function.

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For more complete information about compiler optimizations, see our Optimization Notice.

It is a compiler report. You may read more here:
http://en.wikipedia.org/wiki/Vectorization_(parallel_computing)#Loop-level_automatic_vectorization

Thanks a lot, it is a nice link.

But can you tell me what does vectorized 0 loops means?

That none of your loops were vectorized :)It means the compiler couldn't optimize any loops.

I am using omp, and gcc as a compiler.

There is a way to force the compiler to vectorize my loops?

If there is please tell me

Forcing the compiler to vectorize your loops wouldn't be a good idea if this would be possible (I don't know but you should look at the doc).If you force the compiler to use 128 bit registers and if your code is not scaled to use those kind of registers, you will have worst time than without vectorization.You should probably start by looking at the intrinsic functions if you want to vectorize your code.

-O3 parameter already enables the auto code vectorizing, so you don't need any other flag.

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