[PATCH i386 5/8] [AVX-512] Extend vectorizer hooks.
Thu Jan 2 21:56:00 GMT 2014
> x86-64 ABI has clause about aligning static vars to 128bit boundary at a
> given size. This was introduced to aid compiler to generate aligned
> vector store/load even if the object may bind to other object file.
> This is set to stone and can not be changed for AVX/SSE.
Yes, but that's irrelevant in 32-bit mode.
> For other objects that are fully under local control we can bump up
> alignment more. I remember this code was originally supposed to bump up
> to 128bits since it was written long before AVX. I suppose it would make
> sense to do so when AVX is enabled and we anticipate to use it.
So the same unexpected side-effect (decreasing the alignment) probably happened
when the maximum alignment was bumped from 128 to 256.
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