[clang] [Headers][X86] VectorExprEvaluator::VisitCallExpr - allow SSE/AVX2/AVX512 pack intrinsics to be used in constexpr (PR #156003)

[Simon Pilgrim via cfe-commits]

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@@ -2604,6 +2605,51 @@ static bool interp__builtin_elementwise_int_binop(
   return true;
 }
 
+static bool interp__builtin_x86_pack(
+    InterpState &S, CodePtr, const CallExpr *E,
+    llvm::function_ref<APSInt(const APSInt &)> narrowElement) {
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RKSimon wrote:

narrowElement -> PackFn?

https://github.com/llvm/llvm-project/pull/156003