llvm dev - Jun 2021 - Document to understand vectorized code

Dear all,

Greetings. I have generated a vectorized code from a C source file
(attached). Is there any comprehensive tutorial/document to understand
generated instructions or the semantics of the vectorized code ?

Thanks,
Sudakshina
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Hi Sudakshina,

First, it helps if you can put your code in a godbolt snippet, like this
[1]. It helps people in multiple ways (e.g., they don't have to download
files, they can see exactly what cmd arguments you used, they can
tweak the cmd arguments without having LLVM on their machine etc.).

Is there any comprehensive tutorial/document to understand
generated
> instructions or the semantics of the vectorized code ?

This is quite generic, what is more specifically that you want to
understand? Do you want to understand what each individual instruction
does? Do you maybe understand that but
you don't know what is the general method to generate, let's say by
hand,
vectorized code (or more specifically, branching vectorized code). Or
maybe, you want to understand
how _LLVM_ generates this code, i.e., the inner workings of the
vectorization passes.

Best,
Stefanos

[1] https://godbolt.org/z/8eKqnrMPn

Στις Κυρ, 6 Ιουν 2021 στις 6:17 π.μ., ο/η Sudakshina Dutta via llvm-dev <
llvm-dev at lists.llvm.org> έγραψε:
> Dear all,
>
> Greetings. I have generated a vectorized code from a C source file
> (attached). Is there any comprehensive tutorial/document to understand
> generated instructions or the semantics of the vectorized code ?
>
> Thanks,
> Sudakshina
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
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