[clang] [HLSL] Modify the Matrix orientation to be AST based instead of Attribute (PR #214001)

[Farzon Lotfi via cfe-commits]

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@@ -3766,6 +3766,9 @@ void MicrosoftCXXNameMangler::mangleType(const ConstantMatrixType *T,
 
   Extra.mangleIntegerLiteral(llvm::APSInt::getUnsigned(T->getNumRows()));
   Extra.mangleIntegerLiteral(llvm::APSInt::getUnsigned(T->getNumColumns()));
+  if (std::optional<MatrixType::LayoutKind> Layout = T->getLayout())
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farzonl wrote:

We don't use Microsoft mangler for  HLSL anymore. I added this more to be consistent, but not clear how we can test this code since c++ does not have Matrix layout modifier like HLSL does. Maybe via the clang unit tests?

https://github.com/llvm/llvm-project/pull/214001