[clang] Improve packoffset error message (PR #173077)

[Helena Kotas via cfe-commits]

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@@ -1943,8 +1943,8 @@ void SemaHLSL::handlePackOffsetAttr(Decl *D, const ParsedAttr &AL) {
   // Check Component is valid for T.
   if (Component) {
     unsigned Size = getASTContext().getTypeSize(T);
-    if (IsAggregateTy || Size > 128) {
-      Diag(AL.getLoc(), diag::err_hlsl_packoffset_cross_reg_boundary);
+    if (IsAggregateTy) {
+      Diag(AL.getLoc(), diag::err_hlsl_invalid_register_or_packoffset);
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hekota wrote:

I've updated the description. The `Size > 128` case is handled in the `else` branch on line 1951.

https://github.com/llvm/llvm-project/pull/173077