[clang] [HLSL][Matrix] Update indexed matrix elements individually (PR #176216)

[Farzon Lotfi via cfe-commits]

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@@ -2736,29 +2758,33 @@ void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
       return;
     }
     if (Dst.isMatrixRow()) {
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farzonl wrote:

I feel a little weird about how this case has evolved because now we have two specific HLSL behaviors that are indistinguishable from  what could be supported in other language modes if those language modes chose to implement them. would be possible to move the element updates and the i1 to i32 bool code to either named lambdas or helper functions so that it is more clear that these parts of the code could move to independent HLSL pieces?

https://github.com/llvm/llvm-project/pull/176216