[Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - allow AVX512 VPSHUFBITQMB intrinsics to be used in constexpr

[RKSimon]

These are the last instructions in avx512bitalgintrin.h / avx512vlbitalgintrin.h that require constexpr support

__mmask16 _mm_bitshuffle_epi64_mask (__m128i b, __m128i c)
__mmask16 _mm_mask_bitshuffle_epi64_mask (__mmask16 k, __m128i b, __m128i c)
__mmask32 _mm256_bitshuffle_epi64_mask (__m256i b, __m256i c)
__mmask32 _mm256_mask_bitshuffle_epi64_mask (__mmask32 k, __m256i b, __m256i c)
__mmask64 _mm512_bitshuffle_epi64_mask (__m512i b, __m512i c)
__mmask64 _mm512_mask_bitshuffle_epi64_mask (__mmask64 k, __m512i b, __m512i c)

NOTE: These instructions are not easy - you will need access to a AVX512 machine to thoroughly test your implementation

[llvmbot]

Hi!

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[llvmbot]

@llvm/issue-subscribers-backend-x86

Author: Simon Pilgrim (RKSimon)

These are the last instructions in avx512bitalgintrin.h / avx512vlbitalgintrin.h that require constexpr support ``` __mmask16 _mm_bitshuffle_epi64_mask (__m128i b, __m128i c) __mmask16 _mm_mask_bitshuffle_epi64_mask (__mmask16 k, __m128i b, __m128i c) __mmask32 _mm256_bitshuffle_epi64_mask (__m256i b, __m256i c) __mmask32 _mm256_mask_bitshuffle_epi64_mask (__mmask32 k, __m256i b, __m256i c) __mmask64 _mm512_bitshuffle_epi64_mask (__m512i b, __m512i c) __mmask64 _mm512_mask_bitshuffle_epi64_mask (__mmask64 k, __m512i b, __m512i c) ``` NOTE: These instructions are not easy - you will need access to a AVX512 machine to thoroughly test your implementation

[llvmbot]

@llvm/issue-subscribers-good-first-issue

Author: Simon Pilgrim (RKSimon)

These are the last instructions in avx512bitalgintrin.h / avx512vlbitalgintrin.h that require constexpr support ``` __mmask16 _mm_bitshuffle_epi64_mask (__m128i b, __m128i c) __mmask16 _mm_mask_bitshuffle_epi64_mask (__mmask16 k, __m128i b, __m128i c) __mmask32 _mm256_bitshuffle_epi64_mask (__m256i b, __m256i c) __mmask32 _mm256_mask_bitshuffle_epi64_mask (__mmask32 k, __m256i b, __m256i c) __mmask64 _mm512_bitshuffle_epi64_mask (__m512i b, __m512i c) __mmask64 _mm512_mask_bitshuffle_epi64_mask (__mmask64 k, __m512i b, __m512i c) ``` NOTE: These instructions are not easy - you will need access to a AVX512 machine to thoroughly test your implementation

[kimsh02]

@RKSimon I'll take it

[kimsh02]

@RKSimon Didn't read note, is it okay to do this on macOS silicon? I don't have access to AVX-512 machine, but the intrinsics are evaluated at compile-time anyways.

[RKSimon]

Not sure, I'm expecting these intrinsics to be difficult to confirm correctness and ideally we'd do a large scale fuzz test comparing runtime and constexpr results.

[kimsh02]

@RKSimon Okay makes sense, I'll hand it over to someone who is equipped to test it.