Neon intrinsics

In the meantime, I have tested the Neon Intrinsics. Everything works just fine except for the non-temporal stores. Further, I still need to test sve.

SVE probably needs a bit more work because of its flexible vector width. Since none of us have hardware access, we could also remove it for now.

What's the problem with the non-temporal stores?

I am not sure if I need to set additional flags but __builtin_nontemporal_store is just not known by the compiler.

With SVE I would agree.

Seems like that builtin only exists on clang. According to the ARM ISA manual, the instruction is STNP, and grepping through the gcc source code suggests that gcc does not know it. So you will need a wrapper function that resorts to a regular store, something like

#if defined(__has_builtin) && __has_builtin(__builtin_nontemporal_store)
    __builtin_nontemporal_store(..., ...);
#else
    ...
#endif

I wouldn't want to make use of that. There is exactly the instruction we are searching for

https://developer.arm.com/documentation/100076/0100/a64-instruction-set-reference/a64-data-transfer-instructions/stnp

However, as far as is see this is not available for SIMD types yet. Thus there is no intrinsic available. I think we should drop NT Stores for now until this is more accessible on the arm side.

I also saw that every store intrinsic is also available as a lane version. For example vst1q_f64 and vst1q_lane_f64. I didn`t see any difference in the implementation of those instruction so they are not interesting for us, right?

The lane versions are for extracting individual elements from a vector. So NEON's vst1q_f32 is like SSE's _mm_store_ps, while vst1q_lane_f32 corresponds to _mm_extract_ps.

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30514b76 - Removed SVE and NT Stores for arm

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Ok, this makes sense. I have now removed SVE and NT Stores.

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30514b76...b2b2e912 - 26 commits from branch pycodegen:master
28db0932 - Merge i10git.cs.fau.de:pycodegen/pystencils into Neon_Intrinsics

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28db0932...6effd8d3 - 2 commits from branch pycodegen:master
069b11e7 - Merge https://i10git.cs.fau.de/pycodegen/pystencils into Neon_Intrinsics
1c7399a0 - Merge branch 'Neon_Intrinsics' of https://i9git.cs.fau.de/holzer/pystencils into Neon_Intrinsics
457ea9fe - Merge branch 'Neon_Intrinsics' of https://i10git.cs.fau.de/holzer/pystencils into Neon_Intrinsics
54fb9d89 - Merge https://i10git.cs.fau.de/pycodegen/pystencils into Neon_Intrinsics

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70f63373 - removed NT Stores for neon

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Neon intrinsics

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