Comment by abductee_hg

7 years ago

well there is this: #ifdef _MSC_VER __declspec( align(16) ) struct float4 { float v[4]; }; #else struct float4 { float v[4]; } __attribute__ ((aligned(16))); #endif

but the main problem ist tthat alignment is _not_ part of the typing system. ( alignas vs alignof )

butt, to put it more general: 90% of your performance is in memory access and compilers are rubbish optimizing those, they are however getting increasingly good at the 10%. see also https://www.youtube.com/watch?v=rX0ItVEVjHc for realworld examples/exploration

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abductee_hg

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account42  7 years ago

> well there is this: #ifdef _MSC_VER __declspec( align(16) ) struct float4 { float v[4]; }; #else struct float4 { float v[4]; } __attribute__ ((aligned(16))); #endif

I don't understand what you are trying to say here? Why not just use

    struct alignas(16) float4 { float v[4]; };

You can even put both __declspec( align(16) ) and __attribute__ ((aligned(16))) in the same place if you want to have a fallback for older compilers.