[clang] [HLSL] Preserve matrix layout as AST storage metadata (PR #225519)

[Farzon Lotfi via cfe-commits]

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@@ -44,6 +44,18 @@ column_major float4x4 Col2Row(row_major float4x4 M) {
 
 void bar(row_major float4x4 M, column_major float4x4 M2) {}
 
+// Layout metadata does not create distinct overloads.
+void same_overload(row_major float2x2 M);
+void same_overload(column_major float2x2 M);
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farzonl wrote:

I'll fix up the test. It has been a bit of time so don't have a perfect memory of why but I had an earlier attempt at a patch that https://github.com/llvm/llvm-project/pull/214001/changes/f195c07fa3ed82f00b22c82290bc8e90d85edca3 that treated these as two different functions so overloads not redeclerations and I needed sema type deduction to say they were the same. So was trying to avoid reintroducing anything like that.

https://github.com/llvm/llvm-project/pull/225519