[Headers][X86] Allow SSE2/AVX2/AVX512F/AVX512BW/AVX512DQ integer arithmetic intrinsics to be used in constexpr

[RKSimon]

All of these intrinsics wrap generic implementations which can already be used in constexpr

_mm_add_epi8 _mm_add_epi16 _mm_add_epi32 _mm_add_epi64
_mm_sub_epi8 _mm_sub_epi16 _mm_sub_epi32 _mm_sub_epi64
_mm_mullo_epi32
_mm_cmpeq_epi8 _mm_cmpeq_epi16 _mm_cmpeq_epi32 _mm_cmpeq_epi64
_mm_cmpgt_epi8 _mm_cmpgt_epi16 _mm_cmpgt_epi32 _mm_cmpegt_epi64
_mm_cmplt_epi8 _mm_cmplt_epi16 _mm_cmplt_epi32 _mm_cmplt_epi64

_mm256_add_epi8 _mm256_add_epi16 _mm256_add_epi32 _mm256_add_epi64
_mm256_sub_epi8 _mm256_sub_epi16 _mm256_sub_epi32 _mm256_sub_epi64
_mm256_mullo_epi32
_mm256_cmpeq_epi8 _mm256_cmpeq_epi16 _mm256_cmpeq_epi32 _mm256_cmpeq_epi64
_mm256_cmpgt_epi8 _mm256_cmpgt_epi16 _mm256_cmpgt_epi32 _mm256_cmpegt_epi64

_mm512_add_epi8 _mm512_add_epi16 _mm512_add_epi32 _mm512_add_epi64
_mm512_sub_epi8 _mm512_sub_epi16 _mm512_sub_epi32 _mm512_sub_epi64
_mm512_mullo_epi32
_mm_mullo_epi64 _mm256_mullo_epi64 _mm512_mullo_epi64

(ignore the AVX512 mask/maskz variants for now)

You can use #152296 for reference

[llvmbot]

Hi!

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[llvmbot]

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

Author: Simon Pilgrim (RKSimon)

All of these intrinsics wrap generic implementations which can already be used in constexpr ``` _mm_add_epi8 _mm_add_epi16 _mm_add_epi32 _mm_add_epi64 _mm_sub_epi8 _mm_sub_epi16 _mm_sub_epi32 _mm_sub_epi64 _mm_mullo_epi16 _mm_mullo_epi32

_mm256_add_epi8 _mm256_add_epi16 _mm256_add_epi32 _mm256_add_epi64
_mm256_sub_epi8 _mm256_sub_epi16 _mm256_sub_epi32 _mm256_sub_epi64
_mm256_mullo_epi16 _mm256_mullo_epi32

_mm512_add_epi8 _mm512_add_epi16 _mm512_add_epi32 _mm512_add_epi64
_mm512_sub_epi8 _mm512_sub_epi16 _mm512_sub_epi32 _mm512_sub_epi64
_mm512_mullo_epi16 _mm512_mullo_epi32
_mm_mullo_epi64 _mm256_mullo_epi64 _mm512_mullo_epi64

(ignore the AVX512 mask/maskz variants for now)

You can use https://github.com/llvm/llvm-project/pull/152296 for reference
</details>

[llvmbot]

@llvm/issue-subscribers-backend-x86

Author: Simon Pilgrim (RKSimon)

All of these intrinsics wrap generic implementations which can already be used in constexpr ``` _mm_add_epi8 _mm_add_epi16 _mm_add_epi32 _mm_add_epi64 _mm_sub_epi8 _mm_sub_epi16 _mm_sub_epi32 _mm_sub_epi64 _mm_mullo_epi16 _mm_mullo_epi32

_mm256_add_epi8 _mm256_add_epi16 _mm256_add_epi32 _mm256_add_epi64
_mm256_sub_epi8 _mm256_sub_epi16 _mm256_sub_epi32 _mm256_sub_epi64
_mm256_mullo_epi16 _mm256_mullo_epi32

_mm512_add_epi8 _mm512_add_epi16 _mm512_add_epi32 _mm512_add_epi64
_mm512_sub_epi8 _mm512_sub_epi16 _mm512_sub_epi32 _mm512_sub_epi64
_mm512_mullo_epi16 _mm512_mullo_epi32
_mm_mullo_epi64 _mm256_mullo_epi64 _mm512_mullo_epi64

(ignore the AVX512 mask/maskz variants for now)

You can use https://github.com/llvm/llvm-project/pull/152296 for reference
</details>

[keyvchan]

@RKSimon hi, I would like to try out this. Can I be assigned?