llvm/llvm-project

[X86][Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - add AVX512 integer comparison intrinsics to be used in constexpr

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#162 054 ouverte le 6 oct. 2025

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Description

The core integer comparison intrinsics could be used in constexpr:

_mm_cmp_epi8_mask _mm_cmp_epu8_mask
_mm_cmp_epi16_mask _mm_cmp_epu16_mask
_mm_cmp_epi32_mask _mm_cmp_epu32_mask
_mm_cmp_epi64_mask _mm_cmp_epu64_mask

_mm256_cmp_epi8_mask _mm256_cmp_epu8_mask
_mm256_cmp_epi16_mask _mm256_cmp_epu16_mask
_mm256_cmp_epi32_mask _mm256_cmp_epu32_mask
_mm256_cmp_epi64_mask _mm256_cmp_epu64_mask

_mm512_cmp_epi8_mask _mm512_cmp_epu8_mask
_mm512_cmp_epi16_mask _mm512_cmp_epu16_mask
_mm512_cmp_epi32_mask _mm512_cmp_epu32_mask
_mm512_cmp_epi64_mask _mm512_cmp_epu64_mask

These need to handle the comparison modes detailed in the Intel Intrinsics Guide:

0: OP := _MM_CMPINT_EQ
1: OP := _MM_CMPINT_LT
2: OP := _MM_CMPINT_LE
3: OP := _MM_CMPINT_FALSE
4: OP := _MM_CMPINT_NE
5: OP := _MM_CMPINT_NLT
6: OP := _MM_CMPINT_NLE
7: OP := _MM_CMPINT_TRUE

There are a LOT of wrappers to these intrinsics (e.g. eq/ge/gt/le/lt/neq variants) - ideally we need test coverage for all of them. To avoid incredible boredom you should probably write a script to autogen the TEST_CONSTEXPR lines somehow that you then copy+paste into the relevant locations.

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