[Headers][X86] Allow AVX512 integer reduction intrinsics to be used in constexpr

[RKSimon]

The AVX512 _mm512_reduce_*_epi* intrinsic wrap the builtin reduction intrinsics which can already be used in constexpr:

_mm512_reduce_add_epi32 _mm512_reduce_add_epi64
_mm512_reduce_mul_epi32 _mm512_reduce_mul_epi64

_mm512_reduce_and_epi32 _mm512_reduce_and_epi64
_mm512_reduce_or_epi32 _mm512_reduce_or_epi64

_mm512_reduce_max_epi32 _mm512_reduce_max_epi64
_mm512_reduce_min_epi32 _mm512_reduce_min_epi64
_mm512_reduce_max_epu32 _mm512_reduce_max_epu64
_mm512_reduce_min_epu32 _mm512_reduce_min_epu64

(ignore the AVX512 mask/maskz variants for now)

You can use #152305 as reference.

[llvmbot]

@llvm/issue-subscribers-backend-x86

Author: Simon Pilgrim (RKSimon)

The AVX512 `_mm512_reduce_*_epi*` intrinsic wrap the builtin reduction intrinsics which can already be used in constexpr: ``` _mm512_reduce_add_epi32 _mm512_reduce_add_epi64 _mm512_reduce_mul_epi32 _mm512_reduce_mul_epi64

_mm512_reduce_and_epi32 _mm512_reduce_and_epi64
_mm512_reduce_or_epi32 _mm512_reduce_or_epi64

_mm512_reduce_max_epi32 _mm512_reduce_max_epi64
_mm512_reduce_min_epi32 _mm512_reduce_min_epi64
_mm512_reduce_max_epu32 _mm512_reduce_max_epu64
_mm512_reduce_min_epu32 _mm512_reduce_min_epu64

(ignore the AVX512 mask/maskz variants for now)

You can use https://github.com/llvm/llvm-project/pull/152305 as reference.
</details>

[llvmbot]

Hi!

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[llvmbot]

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

Author: Simon Pilgrim (RKSimon)

The AVX512 `_mm512_reduce_*_epi*` intrinsic wrap the builtin reduction intrinsics which can already be used in constexpr: ``` _mm512_reduce_add_epi32 _mm512_reduce_add_epi64 _mm512_reduce_mul_epi32 _mm512_reduce_mul_epi64

_mm512_reduce_and_epi32 _mm512_reduce_and_epi64
_mm512_reduce_or_epi32 _mm512_reduce_or_epi64

_mm512_reduce_max_epi32 _mm512_reduce_max_epi64
_mm512_reduce_min_epi32 _mm512_reduce_min_epi64
_mm512_reduce_max_epu32 _mm512_reduce_max_epu64
_mm512_reduce_min_epu32 _mm512_reduce_min_epu64

(ignore the AVX512 mask/maskz variants for now)

You can use https://github.com/llvm/llvm-project/pull/152305 as reference.
</details>