[clang] [HLSL][NFC] Move packoffset validation to separate function and calculate offsets in bytes (PR #121989)

[Helena Kotas via cfe-commits]

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@@ -194,17 +196,19 @@ static unsigned calculateLegacyCbufferSize(const ASTContext &Context,
         calculateLegacyCbufferSize(Context, VT->getElementType());
     Size = ElementSize * ElementCount;
   } else {
-    Size = Context.getTypeSize(T);
+    Size = Context.getTypeSize(T) / 8;
   }
   return Size;
 }
 
-void SemaHLSL::ActOnFinishBuffer(Decl *Dcl, SourceLocation RBrace) {
-  auto *BufDecl = cast<HLSLBufferDecl>(Dcl);
-  BufDecl->setRBraceLoc(RBrace);
-
-  // Validate packoffset.
+// Validate packoffset:
+// - make sure if packoffset it used on all decls or none
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hekota wrote:

I've updated the comment to make more sense.

https://github.com/llvm/llvm-project/pull/121989