[clang] [HLSL] Implement output parameter (PR #101083)

[John McCall via cfe-commits]

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@@ -285,6 +285,13 @@ class CallArgList : public SmallVector<CallArg, 8> {
 
     /// A value to "use" after the writeback, or null.
     llvm::Value *ToUse;
+
+    /// An Expression representing a cast from the temporary's type to the
+    /// source l-value's type.
+    const Expr *CastExpr;
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rjmccall wrote:

This comment is no longer correct; consider something like `WritebackExpr`. And maybe the logic for writebacks should simply be that we evaluate this expression if it's present, rather than making a language-mode decision?

https://github.com/llvm/llvm-project/pull/101083