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

[RKSimon]

__m128i _mm_clmulepi64_si128 (__m128i a, __m128i b, const int imm8)
__m256i _mm256_clmulepi64_epi128 (__m256i b, __m256i c, const int Imm8)
__m512i _mm512_clmulepi64_epi128 (__m512i b, __m512i c, const int Imm8)

Now that we have #168527 we should be able to easily constant fold PCLMULQDQ builtins for constant expressions

Ensure you consult https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=clmul and handle the imm8 mask correctly, preferably with offline testing.

[llvmbot]

Hi!

This issue may be a good introductory issue for people new to working on LLVM. If you would like to work on this issue, your first steps are:

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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)

``` __m128i _mm_clmulepi64_si128 (__m128i a, __m128i b, const int imm8) __m256i _mm256_clmulepi64_epi128 (__m256i b, __m256i c, const int Imm8) __m512i _mm512_clmulepi64_epi128 (__m512i b, __m512i c, const int Imm8) ``` Now that we have #168527 we should be able to easily constant fold PCLMULQDQ builtins for constant expressions

Ensure you consult https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=clmul and handle the imm8 mask correctly, preferably with offline testing.

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Simon Pilgrim (RKSimon)

``` __m128i _mm_clmulepi64_si128 (__m128i a, __m128i b, const int imm8) __m256i _mm256_clmulepi64_epi128 (__m256i b, __m256i c, const int Imm8) __m512i _mm512_clmulepi64_epi128 (__m512i b, __m512i c, const int Imm8) ``` Now that we have #168527 we should be able to easily constant fold PCLMULQDQ builtins for constant expressions

Ensure you consult https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=clmul and handle the imm8 mask correctly, preferably with offline testing.

[llvmbot]

@llvm/issue-subscribers-backend-x86

Author: Simon Pilgrim (RKSimon)

``` __m128i _mm_clmulepi64_si128 (__m128i a, __m128i b, const int imm8) __m256i _mm256_clmulepi64_epi128 (__m256i b, __m256i c, const int Imm8) __m512i _mm512_clmulepi64_epi128 (__m512i b, __m512i c, const int Imm8) ``` Now that we have #168527 we should be able to easily constant fold PCLMULQDQ builtins for constant expressions

Ensure you consult https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=clmul and handle the imm8 mask correctly, preferably with offline testing.

[ahmednoursphinx]

Hey @RKSimon i would like to work on this if possible