[clang] [X86][Clang] Support constexpr evaluation of cvtpd2ps intrinsics (PR #169980)

[Simon Pilgrim via cfe-commits]

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@@ -12165,7 +12165,36 @@ static bool evalShuffleGeneric(
   Out = APValue(ResultElements.data(), ResultElements.size());
   return true;
 }
+static bool ConvertDoubleToFloatStrict(EvalInfo &Info, const Expr *E,
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RKSimon wrote:

Equivalent InterpBuiltin.cpp handling?

https://github.com/llvm/llvm-project/pull/169980