[clang] [CIR] Pass x87 long double vectors on x86_64 (PR #230302)

[Andy Kaylor via cfe-commits]

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@@ -159,6 +159,55 @@ static bool hasIncompleteRecordByValue(mlir::Type ty) {
   return false;
 }
 
+/// Whether \p ty has the x87 80-bit format, wrapped in LongDoubleType or not.
+static bool isX87LongDouble(mlir::Type ty) {
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andykaylor wrote:

I don't like "long double" here (and throughout this PR). To me, "long double" is a C/C++ type. Why not use `double extended` as APFloat does?

https://github.com/llvm/llvm-project/pull/230302