[clang] [HLSL] Add matrix constructors using initalizer lists (PR #162743)

[Farzon Lotfi via cfe-commits]

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@@ -1877,6 +1887,93 @@ void InitListChecker::CheckReferenceType(const InitializedEntity &Entity,
     AggrDeductionCandidateParamTypes->push_back(DeclType);
 }
 
+void InitListChecker::CheckMatrixType(const InitializedEntity &Entity,
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farzonl wrote:

That said the diagnostics in `CheckMatrixType` never trigger and are now preceded by the ones in SemaHLSL and the flatten mixed vector/matrix/scalar elements is also done in SemaHLSL so I will investigate to see if we can reduce the scope of what `CheckMatrixType` is doing.

https://github.com/llvm/llvm-project/pull/162743