[X86][Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - allow PD2PS fp truncation intrinsics to be used in constexpr

[RKSimon]

Similar to #160312 except initially we should only allow EXACT and FINITE conversions - any special case (DENORMAL/INF/NAN/etc.) or loss of precision shouldn't be allowed in constexpr for now.

__m128 _mm_cvtsd_ss (__m128 a, __m128d b)
__m128 _mm_mask_cvtsd_ss (__m128 src, __mmask8 k, __m128 a, __m128d b)
__m128 _mm_maskz_cvtsd_ss (__mmask8 k, __m128 a, __m128d b)

__m128 _mm_cvtpd_ps (__m128d a)
__m128 _mm_mask_cvtpd_ps (__m128 src, __mmask8 k, __m128d a)
__m128 _mm_maskz_cvtpd_ps (__mmask8 k, __m128d a)
__m128 _mm256_cvtpd_ps (__m256d a)
__m128 _mm256_mask_cvtpd_ps (__m128 src, __mmask8 k, __m256d a)
__m128 _mm256_maskz_cvtpd_ps (__mmask8 k, __m256d a)
__m256 _mm512_cvtpd_ps (__m512d a)
__m256 _mm512_mask_cvtpd_ps (__m256 src, __mmask8 k, __m512d a)
__m256 _mm512_maskz_cvtpd_ps (__mmask8 k, __m512d a)
__m512 _mm512_cvtpd_pslo (__m512d v2)
__m512 _mm512_mask_cvtpd_pslo (__m512 src, __mmask8 k, __m512d v2)

[llvmbot]

@llvm/issue-subscribers-backend-x86

Author: Simon Pilgrim (RKSimon)

Similar to #160312 except initially we should only allow EXACT and FINITE conversions - any special case (DENORMAL/INF/NAN/etc.) or loss of precision shouldn't be allowed in constexpr for now. ``` __m128 _mm_cvtsd_ss (__m128 a, __m128d b) __m128 _mm_mask_cvtsd_ss (__m128 src, __mmask8 k, __m128 a, __m128d b) __m128 _mm_maskz_cvtsd_ss (__mmask8 k, __m128 a, __m128d b)

__m128 _mm_cvtpd_ps (__m128d a)
__m128 _mm_mask_cvtpd_ps (__m128 src, __mmask8 k, __m128d a)
__m128 _mm_maskz_cvtpd_ps (__mmask8 k, __m128d a)
__m128 _mm256_cvtpd_ps (__m256d a)
__m128 _mm256_mask_cvtpd_ps (__m128 src, __mmask8 k, __m256d a)
__m128 _mm256_maskz_cvtpd_ps (__mmask8 k, __m256d a)
__m256 _mm512_cvtpd_ps (__m512d a)
__m256 _mm512_mask_cvtpd_ps (__m256 src, __mmask8 k, __m512d a)
__m256 _mm512_maskz_cvtpd_ps (__mmask8 k, __m512d a)
__m512 _mm512_cvtpd_pslo (__m512d v2)
__m512 _mm512_mask_cvtpd_pslo (__m512 src, __mmask8 k, __m512d v2)

</details>

[llvmbot]

Hi!

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If you have any further questions about this issue, don't hesitate to ask via a comment in the thread below.

[llvmbot]

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

Author: Simon Pilgrim (RKSimon)

Similar to #160312 except initially we should only allow EXACT and FINITE conversions - any special case (DENORMAL/INF/NAN/etc.) or loss of precision shouldn't be allowed in constexpr for now. ``` __m128 _mm_cvtsd_ss (__m128 a, __m128d b) __m128 _mm_mask_cvtsd_ss (__m128 src, __mmask8 k, __m128 a, __m128d b) __m128 _mm_maskz_cvtsd_ss (__mmask8 k, __m128 a, __m128d b)

__m128 _mm_cvtpd_ps (__m128d a)
__m128 _mm_mask_cvtpd_ps (__m128 src, __mmask8 k, __m128d a)
__m128 _mm_maskz_cvtpd_ps (__mmask8 k, __m128d a)
__m128 _mm256_cvtpd_ps (__m256d a)
__m128 _mm256_mask_cvtpd_ps (__m128 src, __mmask8 k, __m256d a)
__m128 _mm256_maskz_cvtpd_ps (__mmask8 k, __m256d a)
__m256 _mm512_cvtpd_ps (__m512d a)
__m256 _mm512_mask_cvtpd_ps (__m256 src, __mmask8 k, __m512d a)
__m256 _mm512_maskz_cvtpd_ps (__mmask8 k, __m512d a)
__m512 _mm512_cvtpd_pslo (__m512d v2)
__m512 _mm512_mask_cvtpd_pslo (__m512 src, __mmask8 k, __m512d v2)

</details>

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Simon Pilgrim (RKSimon)

Similar to #160312 except initially we should only allow EXACT and FINITE conversions - any special case (DENORMAL/INF/NAN/etc.) or loss of precision shouldn't be allowed in constexpr for now. ``` __m128 _mm_cvtsd_ss (__m128 a, __m128d b) __m128 _mm_mask_cvtsd_ss (__m128 src, __mmask8 k, __m128 a, __m128d b) __m128 _mm_maskz_cvtsd_ss (__mmask8 k, __m128 a, __m128d b)

__m128 _mm_cvtpd_ps (__m128d a)
__m128 _mm_mask_cvtpd_ps (__m128 src, __mmask8 k, __m128d a)
__m128 _mm_maskz_cvtpd_ps (__mmask8 k, __m128d a)
__m128 _mm256_cvtpd_ps (__m256d a)
__m128 _mm256_mask_cvtpd_ps (__m128 src, __mmask8 k, __m256d a)
__m128 _mm256_maskz_cvtpd_ps (__mmask8 k, __m256d a)
__m256 _mm512_cvtpd_ps (__m512d a)
__m256 _mm512_mask_cvtpd_ps (__m256 src, __mmask8 k, __m512d a)
__m256 _mm512_maskz_cvtpd_ps (__mmask8 k, __m512d a)
__m512 _mm512_cvtpd_pslo (__m512d v2)
__m512 _mm512_mask_cvtpd_pslo (__m512 src, __mmask8 k, __m512d v2)

</details>

[HamzaHassanain]

Hello Simon. Hope you are doing well. Can I get assigned this issue, please?