[Headers][X86] Allow PSHUFD/PSHUFLW/PSHUFW shuffle intrinsics to be used in constexpr

[RKSimon]

The i16/i32 fixed shuffle intrinsics can be used in constant expressions:

_mm_shuffle_pi16

_mm_shufflelo_epi16 _mm_mask_shufflelo_epi16 _mm_maskz_shufflelo_epi16
_mm256_shufflelo_epi16 _mm256_mask_shufflelo_epi16 _mm256_maskz_shufflelo_epi16
_mm512_shufflelo_epi16 _mm512_mask_shufflelo_epi16 _mm512_maskz_shufflelo_epi16

_mm_shufflehi_epi16 _mm_mask_shufflehi_epi16 _mm_maskz_shufflehi_epi16
_mm256_shufflehi_epi16 _mm256_mask_shufflehi_epi16 _mm256_maskz_shufflehi_epi16
_mm512_shufflehi_epi16 _mm512_mask_shufflehi_epi16 _mm512_maskz_shufflehi_epi16

_mm_shuffle_epi32 _mm_mask_shuffle_epi32 _mm_maskz_shuffle_epi32
_mm256_shuffle_epi32 _mm256_mask_shuffle_epi32 _mm256_maskz_shuffle_epi32
_mm512_shuffle_epi32 _mm512_mask_shuffle_epi32 _mm512_maskz_shuffle_epi32

These will require handling inside VectorExprEvaluator::VisitCallExpr / InterpretBuiltin

Similar testing to #153102 - single test for each intrinsic, but ensure a range of masks are used.

[RKSimon]

CC @NagrajMG in case you're still interested in shuffle constexpr issues

[NagrajMG]

Yeah, I will take this up!

[llvmbot]

Hi!

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[llvmbot]

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

Author: Simon Pilgrim (RKSimon)

The i16/i32 fixed shuffle intrinsics can be used in constant expressions: ``` _mm_shuffle_pi16

_mm_shufflelo_epi16 _mm_mask_shufflelo_epi16 _mm_maskz_shufflelo_epi16
_mm256_shufflelo_epi16 _mm256_mask_shufflelo_epi16 _mm256_maskz_shufflelo_epi16
_mm512_shufflelo_epi16 _mm512_mask_shufflelo_epi16 _mm512_maskz_shufflelo_epi16

_mm_shufflehi_epi16 _mm_mask_shufflehi_epi16 _mm_maskz_shufflehi_epi16
_mm256_shufflehi_epi16 _mm256_mask_shufflehi_epi16 _mm256_maskz_shufflehi_epi16
_mm512_shufflehi_epi16 _mm512_mask_shufflehi_epi16 _mm512_maskz_shufflehi_epi16

_mm_shuffle_epi32 _mm_mask_shuffle_epi32 _mm_maskz_shuffle_epi32
_mm256_shuffle_epi32 _mm256_mask_shuffle_epi32 _mm256_maskz_shuffle_epi32
_mm512_shuffle_epi32 _mm512_mask_shuffle_epi32 _mm512_maskz_shuffle_epi32

These will require handling inside VectorExprEvaluator::VisitCallExpr / InterpretBuiltin

Similar testing to #<!-- -->153102 - single test for each intrinsic, but ensure a range of masks are used.
</details>

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Simon Pilgrim (RKSimon)

The i16/i32 fixed shuffle intrinsics can be used in constant expressions: ``` _mm_shuffle_pi16

_mm_shufflelo_epi16 _mm_mask_shufflelo_epi16 _mm_maskz_shufflelo_epi16
_mm256_shufflelo_epi16 _mm256_mask_shufflelo_epi16 _mm256_maskz_shufflelo_epi16
_mm512_shufflelo_epi16 _mm512_mask_shufflelo_epi16 _mm512_maskz_shufflelo_epi16

_mm_shufflehi_epi16 _mm_mask_shufflehi_epi16 _mm_maskz_shufflehi_epi16
_mm256_shufflehi_epi16 _mm256_mask_shufflehi_epi16 _mm256_maskz_shufflehi_epi16
_mm512_shufflehi_epi16 _mm512_mask_shufflehi_epi16 _mm512_maskz_shufflehi_epi16

_mm_shuffle_epi32 _mm_mask_shuffle_epi32 _mm_maskz_shuffle_epi32
_mm256_shuffle_epi32 _mm256_mask_shuffle_epi32 _mm256_maskz_shuffle_epi32
_mm512_shuffle_epi32 _mm512_mask_shuffle_epi32 _mm512_maskz_shuffle_epi32

These will require handling inside VectorExprEvaluator::VisitCallExpr / InterpretBuiltin

Similar testing to #<!-- -->153102 - single test for each intrinsic, but ensure a range of masks are used.
</details>

[llvmbot]

@llvm/issue-subscribers-backend-x86

Author: Simon Pilgrim (RKSimon)

The i16/i32 fixed shuffle intrinsics can be used in constant expressions: ``` _mm_shuffle_pi16

_mm_shufflelo_epi16 _mm_mask_shufflelo_epi16 _mm_maskz_shufflelo_epi16
_mm256_shufflelo_epi16 _mm256_mask_shufflelo_epi16 _mm256_maskz_shufflelo_epi16
_mm512_shufflelo_epi16 _mm512_mask_shufflelo_epi16 _mm512_maskz_shufflelo_epi16

_mm_shufflehi_epi16 _mm_mask_shufflehi_epi16 _mm_maskz_shufflehi_epi16
_mm256_shufflehi_epi16 _mm256_mask_shufflehi_epi16 _mm256_maskz_shufflehi_epi16
_mm512_shufflehi_epi16 _mm512_mask_shufflehi_epi16 _mm512_maskz_shufflehi_epi16

_mm_shuffle_epi32 _mm_mask_shuffle_epi32 _mm_maskz_shuffle_epi32
_mm256_shuffle_epi32 _mm256_mask_shuffle_epi32 _mm256_maskz_shuffle_epi32
_mm512_shuffle_epi32 _mm512_mask_shuffle_epi32 _mm512_maskz_shuffle_epi32

These will require handling inside VectorExprEvaluator::VisitCallExpr / InterpretBuiltin

Similar testing to #<!-- -->153102 - single test for each intrinsic, but ensure a range of masks are used.
</details>