[clang] [Headers][X86] Allow pmuludq/pmuldq to be used in constexpr (PR #153293)

[Phoebe Wang via cfe-commits]

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@@ -344,6 +344,7 @@ __m128i test_mm_mul_epi32(__m128i x, __m128i y) {
   // CHECK: mul <2 x i64> %{{.*}}, %{{.*}}
   return _mm_mul_epi32(x, y);
 }
+TEST_CONSTEXPR(match_m128i(_mm_mul_epi32((__m128i)(__v8hi){+1, -2, +3, -4, +5, -6, +7, -8}, (__m128i)(__v8hi){-16, -14, +12, +10, -8, +6, -4, +2}), 111670394864, -180383186984));
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phoebewang wrote:

ditto.

https://github.com/llvm/llvm-project/pull/153293