[clang] Enable matrices in HLSL (PR #111415)

[Chris B via cfe-commits]

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@@ -852,34 +852,50 @@ void TypePrinter::printExtVectorAfter(const ExtVectorType *T, raw_ostream &OS) {
 
 void TypePrinter::printConstantMatrixBefore(const ConstantMatrixType *T,
                                             raw_ostream &OS) {
+  if (Policy.UseHLSLTypes)
+    OS << "matrix<";
   printBefore(T->getElementType(), OS);
-  OS << " __attribute__((matrix_type(";
-  OS << T->getNumRows() << ", " << T->getNumColumns();
-  OS << ")))";
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llvm-beanz wrote:

This change seems wrong to me. IIUC this changes something like `float  __attribute__((matrix_type(4, 4)))*` to `float * __attribute__((matrix_type(4, 4)))`, which would mean the element type is `float*` rather than `float`.

https://github.com/llvm/llvm-project/pull/111415